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S C I E N C E F O R D E C I S I O N M A K E R S
Risk AssessmentR i s k A s s e s s m e n tin Food Safety Policy and Practice
S. U. Fabiansson
Bureau of Rural Sciences
BRS/Risk Assess Cover.FA 11/7/01 3:18 PM Page 1
Risk AssessmentR i s k A s s e s s m e n tin Food Safety Policy and Practice
S. U. Fabiansson
Bureau of Rural Sciences
Risk Assessment Doc.FA 11/7/01 3:13 PM Page i
Hazards and risks are now commonly used words in industry and government when
dealing with food safety issues. To create uniform ground, the terminology has been
defined by international agreement, and several studies initiated to explore food
safety hazards and their associated risks in more depth. Results point to the
increased importance of a systematic approach when attending to food safety
problems. 'Risk assessment' can provide that systematic approach.
This report describes the relationship between hazards and food safety risks and
explains how objective risk assessment in the future will be able to assist in the
refinement of HACCP-based quality systems. Microbial risk assessment is in a stage
of rapid evolution. We do not suggest that individual companies should immediately
adopt the methodology before it has been proven in practice. However, it is
important both for industry and for governments to follow developments and
be ready to implement new techniques as they become available.
Risk assessment is an objective, science-based method. As such, specialists are
needed to gather information, construct appropriate models and complete the
analysis. However, custom-made solutions are starting to become available for
industry application as well. This report aims to provide sufficient information
to give an understanding of the intricacies of risk assessment, its potential for
practical application, and links to further information sources for more in-depth
descriptions. It provides some practical examples of tools for risk-ranking in order
to set priorities for further action.
Dr Peter O’BrienExecutive Director
© Commonwealth of Australia
This work is copyright. The Copyright Act 1968 permits fair dealing for
study, research, news reporting, criticism or review. Selected passages,
tables or diagrams may be reproduced for such purposes provided that
acknowledgment of the source is included.
Major extracts or the entire document may not be reproduced by any
process without written permission of the Executive Director, Bureau
of Rural Sciences, PO Box E11, Kingston ACT 2604.
The Bureau of Rural Sciences (BRS) is the science agency within
the Commonwealth Department of Agriculture, Fisheries and
Forestry – Australia.
Postal address:
Bureau of Rural Sciences
PO Box E11
Kingston, ACT 2604
Internet: http://www.affa.gov.au/output/ruralscience.html
Preferred way to cite this publication:
Fabiansson, S.U. (2001) Risk assessment in food safety policy
and practice. Bureau of Rural Sciences, Canberra.
This booklet does not represent professional advice given by the
Commonwealth or any other person acting for the Commonwealth for
any particular purpose. It should not be relied on as the basis for any
decision to take action on any matter that it covers. Readers should make
their own enquiries and obtain professional advice, where appropriate,
before making any decision.
The Commonwealth and all persons acting for the Commonwealth
in preparing this booklet disclaim all responsibility and liability
to any person arising directly or indirectly from any person taking
or not taking action based upon the information in this booklet.
iiiii R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c eB u r e a u o f R u r a l S c i e n c e s
F o r e w o r dForeword
Risk Assessment Doc.FA 11/7/01 3:13 PM Page ii
This is an overview of quantitative risk assessment and its use in the food industry
to manage microbiological hazards. The report is directed to policy makers and
industry practitioners and provides a link between objective scientific information
and the development and implementation of improved food safety systems.
Growing acceptance of the principles of risk analysis has led to its use expanding
beyond regulatory standard-setting. Applying risk analysis and risk assessment
to microbial and chemical food safety hazards has recently been advocated
to facilitate international trade, to serve as a basis for sound food safety policy,
and to validate and specify criteria for hazard analysis critical control point (HACCP)
programs. Risk assessment is always the scientific component of the process, but
methodology will vary according to the intended use of the information. A well-
researched quantitative approach is most often a requirement for developing
government food safety policy, but a semi-quantitative or qualitative estimate
could be sufficient for the hazard analysis step in developing an HACCP plan.
A formal quantitative risk assessment (QRA) is demanding of resources and
requires particular expertise. It can take several years to complete all the steps
of a QRA and it often involves international collaboration. It is probably not
feasible for industry to undertake a formal QRA in developing an HACCP program.
However, published QRA information can be used as a basis for assessing
the effect of suggested critical control point interventions in a production system.
A more expedient method to objectively quantify risks is to use expert knowledge.
A number of experts are asked for their opinion in relation to steps in the process,
and a composite picture is then developed by the expert panel to complete the
risk assessment.
At an industry level, a complex questionnaire has been developed with a scoring
system to assess relative risks and to prioritise necessary action.
A similar system is used in a spreadsheet model using a through-chain approach
to calculate a computerised risk ranking score.
Finally, decision tree flow charts can be used to lead the risk assessor through
a simple qualitative approach of assessing risks. This is the most common way
in industry to improve on simple experience and gut feel in analysing hazards
and their potential effect.
Risk assessmentcan be used torank food safetyhazards
vR i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c eiv B u r e a u o f R u r a l S c i e n c e s
Different tools forrisk assessment in practice
E x e c u t i v e S u m m a r yExecutive Summary
Risk Assessment Doc.FA 11/7/01 3:13 PM Page iv
Foreword iii
Executive summary v
Introduction 1
Risk assessment—a scientific approach 2
Linkages between risk analysis and HACCP 3
Risk assessment in safe food production 6
Risk assessment and international food standards 6
Risk assessment and national food standards 7
Risk assessment and individual food companies 8
Strengths and limitations of risk assessment 9
Methods for risk assessment 10
Quantitative risk assessment 11
Expert panel analysis 11
Questionnaire ranking tool 11
Computerised risk ranking tool 12
Decision tree flow chart 12
Experience and gut feel 12
International guidelines 12
Reports on quantitative risk assessment 13
International case studies 13
Domestic studies 19
Gap analysis 24
Lack of coordination 24
Lack of knowledge 24
Lack of information sources 24
Gap between science and practice 25
Lack of useful tools 25
Lack of practical industry examples 24
References 26
Appendix 1 – Quantitative risk assessment 31
Appendix 2 – Expert opinion 34
Appendix 3 – Questionnaire ranking tool 36
Appendix 4 – Computerised risk ranking 42
Appendix 5 – Decision tree flow chart 44
viiR i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c eB u r e a u o f R u r a l S c i e n c e svi
Several quantitative microbial risk assessments have been published or are well
under way. Assessments of this kind are set up to evaluate one particular hazard
in one type of product, and cannot be generalised.Specific microorganisms covered
include Salmonella spp., Listeria monocytogenes, Bacillus cereus, Clostridium spp.,
Vibrio spp., Shiga toxin producing Escherichia coli and Campylobacter spp. Products
covered so far include (number of studies in brackets):
• egg and egg products (6);
• ready-to-eat food (7);
• seafood (8);
• poultry meat (5);
• beef (4);
• smallgoods (2);
• dairy products (5); and
• plant products (2).
The above studies can be used as a starting point for government and industry
in implementing practical measures to secure a safe food production system. Despite
international efforts to harmonise the application of risk assessment methodology,
many questions remain unanswered.
A gap analysis was undertaken to identify issues and suggest actions to improve
the usefulness of risk assessment in HACCP-based industry quality systems. The
following points were noted:
• Risk assessment is still very much a scientific discipline, and support to industry
case studies would help evaluate the relevance of integrating risk assessment
with HACCP development. Development of practical, industry-focused tools
should be facilitated.
• Several Australian initiatives have begun, but fragmented efforts could benefit
from further coordination.
• Knowledge gained in applying risk assessments to practical problem solving
is still to filter through to industry practitioners. Information access is limited
and could be facilitated through formation of a web-based risk-clearing house.
C o n t e n t sContents
Quantitative riskassessments in
the literature
Risk Assessment Doc.FA 11/7/01 3:13 PM Page vi
Once the importance of food security is realised, a safe food supply is seen as essential.
Governments initially responded by introducing food legislation for visual inspection and end-
product testing. This was not sufficient, and recently quality systems, based on hazard analysis
critical control point (HACCP) principles, have been adopted by industry (Troutt et al. 1995,
Berends and van Knapen 1999, Fabiansson and Cunningham 2000). Ideally, safety can now
be engineered into the production process with a much improved outcome, but a detailed
knowledge of food safety hazards and associated public health risks is critical to success
(Buchanan and Whiting 1998, Morales 1998).
Risk assessment has always been part of human activities. Responses have been mainly
intuitive and countermeasures, based on previous experience, applied on a hit-and-miss basis.
Characterising the potential risk to human health and safety posed by modern food production
systems is a much more complex task. There is thus an urgent need to find an objective risk-
assessment process that can improve decision-making in food production. General principles
have been agreed to, although various aspects of the theory and practice continue to be debated
among scientists, risk professionals, policy makers, industry, and the risk-interested public
(Anon. 2000a).
Figure 1. Some international and national organisations involved in harmonising risk assessment methodology.
Guidelines for risk assessment have been issued through several international and national
organisations (see Figure 1):
• The US National Research Council published a report on the topic in the early 1980s
(Anon. 1983).
• The World Health Organisation, the Food and Agriculture Organisation and their joint body,
the Codex Alimentarius Commission (Codex), have issued principles and guidelines for risk
assessment (Anon. 1999).
Appendix 6 – Further reading 46
Web information 46
Useful literature 47
Glossary 48
Figures
1. Some international and national organisations involved in harmonising 1
risk assessment methodology
2. The triad constituting risk analysis 2
3. Integration of risk assessment into HACCP-system development 3
4. The difference between a harmful agent (hazard) and its likelihood 5
of causing disease and its severity (risk) …
5. Risk assessment continuum 6
6. The selective use of risk assessment tools by different participants
in the food chain 10
7. Decision tree flow chart 45
Tables
1. International quantitative risk assessment case studies sorted according 13
to product category covered
2. Australian risk assessment case studies of different products or product categories 19
1viii R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c eB u r e a u o f R u r a l S c i e n c e s
I n t r o d u c t i o nIntroduction
Risk Assessment Doc.FA 11/7/01 3:13 PM Page viii
L i n k a g e s b e t w e e n r i s k a n a l y s i s a n d H A C C P
The growing acceptance of the principles of risk analysis has led to its use expanding beyond
regulatory standard setting. The application of risk analysis and risk assessment strategies
to microbial and chemical food safety hazards has recently been advocated to facilitate
international trade, to serve as a basis for sound food safety policy, and to validate and specify
criteria for HACCP programs (Kindred 1996, Käferstein et al. 1997). Risk assessment is always
the scientific component of the process but methodology will vary according to the intended
use of the information. A well-researched quantitative approach is most often a requirement for
development of government food safety policy, while a semi-quantitative or qualitative estimate
could be sufficient for the hazard analysis step in developing an HACCP plan (Morales 1998,
van Gerwen et al. 2000).
Risk assessment is a systematic approach for capturing information to describe and estimate
the likelihood and impact of adverse events (Kindred 1996). It is generally considered
to consist of four steps: hazard identification, exposure assessment, hazard characterisation
and risk characterisation (Lammerding and Fazil 2000). The knowledge in each step is combined
to represent a cause-and-effect chain from the prevalence and concentration of the pathogen
or chemical to the probability and magnitude of health impacts (see Figure 3). The process
can be structured in many different ways depending on the nature of the risk-
• The Australia New Zealand Food Authority published a framework for assessing
and managing food safety risks (Anon. 1996).
• A Scientific Steering Committee Working Group of the European Commission
has recommended harmonisation of risk-assessment procedures (Anon. 2000a).
• The Office International des Epizooties has issued risk analysis guidelines pertaining
to animal infectious diseases (Anon. 2000b).
R i s k a s s e s s m e n t — a s c i e n t i f i c a p p r o a c h
It is generally agreed that risk assessment is the process through which information on risks
is identified, organised and analysed in a systematic way to get a clear, consistent presentation
of the data available for practical decision making (Rodricks 1999). Risk assessment was initially
introduced in the early 1970s as a discipline using scientific data to quantitatively evaluate human
cancer risk (Potter 1996). The methodology has been refined and adapted for application in other
fields, and the concept of integrating scientific assessment with practical management
considerations and ongoing communication merged into an overall definition of risk analysis
(Anon. 1999). Codex is now defining risk analysis as a consistent, open and transparent process
following a structured approach consisting of three components: risk assessment, risk
management and risk communication. This report covers the topic of risk assessment, but the
triad composing risk analysis is intertwined (see Figure 2), and the scope of a risk assessment
will depend on its intended use in risk management and risk communication.
The three elements of risk analysis have been given specific meanings:
• Risk assessment is a process of evaluation, including the identification of the attendant
uncertainties, and of the likelihood and severity of an adverse effect occurring to humans
following exposure under defined conditions to an apparent hazard.
• Risk management is the process of weighing policy alternatives in the light of the result
of a risk assessment and of other relevant evaluations, and, if required, of selecting and
implementing appropriate control options.
• Risk communication is the interactive exchange of information and opinions throughout
the risk-analysis process concerning risk. It should involve not only risk assessors and risk
managers, but also consumers and a wide range of other actual or potential stakeholders.
As an integrated part of risk analysis, the scientific reliability and
relevance of the risk assessment is of crucial importance for the
validity of the whole risk-analysis process. Risk assessment, properly
defined and applied, is the most appropriate tool currently
available for quantifying the risks associated with microbial
and chemical contamination of foods (Morales 1998).
32 R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c eB u r e a u o f R u r a l S c i e n c e s
RiskAssessment
RiskManagement
RiskCommunication
HACCP
RiskCharacterisation
HazardIdentification
ExposureAssessment
HazardCharacterisation
Risk Assessment
Hazard Analysis
Critical ControlPoints
CriticalLimits
Monitoring System
CorrectiveAction
Verification
Documentation
Figure 3. Integration of risk assessment into HACCP-system developmentFigure 2. The triad constituting risk analysis.
Risk Assessment Doc.FA 11/7/01 3:13 PM Page 2
HACCP planning is already an information-intensive process. Moving from a qualitative hazard
analysis to a quantitative risk assessment increases both the extent of the data needed and the
sophistication required of the team performing the evaluation. Such an undertaking is well
beyond the capabilities of many individual food companies. However, the development
of user-friendly software that takes the manufacturer through the process of developing HACCP
plans, evaluating microbiological risks, and establishing performance standards is already being
envisioned to help the small producer take advantage of these conceptual tools. Dynamic risk-
assessment models can be developed by industry organisations covering the entire farm-to-table
continuum, considering each step that influences the overall risk. Such models can sequentially
link a series of probabilistic process steps and control measures in the form of critical limits for
critical control points. The ability to include the variability associated with each of these steps,
to perform sensitivity analyses, and to conduct failure scenarios potentially provides a more
analytical approach to identifying critical control points. The effect both of critical points and
critical control points can be integrated to consider the overall effectiveness of the entire process.
A dynamic model would allow individual companies to amend the parameters to reflect their
individual production system (Buchanan and Whiting 1998).
The difficulty involved in integrating quantitative risk-assessment methodology into the HACCP
process should not be underestimated. Lack of readily available data can severely hamper any
attempt at constructing a through-chain model. Microbiological ecology of foods is still very much
an evolving field. Human dose-response data is often lacking, and variability in sensitivity levels
can be large between sub-populations. Similar problems faced toxicologists assessing chemical
risks; they were overcome by creating a number of default assumptions and safety margin
allowances. Microbial risk assessment has not yet arrived at that point, and thus acceptable risks
still need to be defined. This is particularly true for industry applications, and there is an urgent
need to develop industry case studies to test theories in realistic settings in order to recommend
practical solutions.
5R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c e
The HACCP system identifies specific hazards, estimates risks and establishes specific control
measures to ensure the safety of food. It is a tool that emphasises prevention and control rather
than reliance on end-product testing and traditional inspection methods. The seven principles
of HACCP are: hazard analysis, critical control point identification, critical limit specification,
monitoring system, corrective actions, verification and documentation. Implicit in developing
an HACCP plan is the use of some form of risk assessment. This is normally at a cursory
level when identifying process and product hazards and setting control measures to avoid
unacceptable contamination. The HACCP methodology has greatly assisted the agrifood industry
in systematically designing programs to ensure the microbiological safety of foods. Unfortunately,
the scope of HACCP programs has been limited by reliance on qualitative measures of hazards
and their control. Qualitative measures cannot easily quantify the combined effect of multiple
control-point deviations or relate the successful operation of an HACCP system to measurable
public health impact. Recent advances in quantitative microbial risk assessment seem to provide
a means for overcoming those obstacles (Buchanan and Whiting 1998).
The integration of HACCP plans with dynamic risk-assessment models offers a means
of considering the entire farm-to-table continuum and for relating food-manufacturing
operations to public health goals. Such capabilities may be critical in establishing equivalence
among HACCP systems. Inclusion of objective risk assessment in the HACCP process can help
decide unacceptable levels of contaminants and provide a scientific rigour to the process to better
withstand third-party auditing. In particular, dynamic microbial risk-assessment models that
incorporate simulation techniques provide a means for dealing with the variabilities associated
with food raw materials. For producers of products for which there is no definitive lethal
processing step, like most production of raw agricultural commodities, or for those that have
formulations that are based on multiple barriers, integrating quantitative risk-assessment
techniques into HACCP plan development may be critical in demonstrating product safety
(Notermans and Mead 1996, Morales 1998, Buchanan and Whiting 1998, McNab 1998).
The use of HACCP and risk assessment within the food industry is still something of a novelty,
and many concepts and techniques need further explanation. While the thrust of HACCP
is simple, a number of underlying concepts are only poorly defined and often not widely
considered. This has lead to confusion concerning some of the very basic principles of HACCP.
The distinction between risk and a hazard is one of them. Commonly these words are used
interchangeably, but from a scientific standpoint they have different meanings (Ahl et al.
1993, Kaplan 1997). Risk assessment involves the identification of hazards and the methodical
description of a system and all its possible failures that could give rise to public exposure to the
hazard. A hazard is defined as any adverse event. The concept of risk, however, includes the
chance that the hazard will occur, and some measure of the consequences if it does (see Figure
4). Thus, the end-result of a risk assessment is an overall picture of the likelihood of the hazard
being realised and the severity of the impact if it is. The term “safety” is often used to describe
situations in which there is no appreciable risk
4 B u r e a u o f R u r a l S c i e n c e s
likelihood of harm and severity of impact
Risk
an agent with the potential to cause harm
Hazard
Figure 4. The difference between a harmful agent (hazard) and its likelihood of causing disease and its severity (risk).
Risk Assessment Doc.FA 11/7/01 3:13 PM Page 4
The increased volume of the global food trade underscores the need for sound epidemiologic
information and international risk assessment. In this regard, Article 5 of the Sanitary and
Phytosanitary Measures Agreement explicitly requires WTO members to conduct scientific
and consistent risk assessments. Furthermore, the World Health Organisation (WHO)
has recommended the application of the HACCP system at every stage of the food chain
as an effective approach for governments to meet the terms outlined in the agreement.
The issue is receiving more attention from regulatory agencies, initially underlined by the Food
and Agriculture Organisation (FAO)/WHO Conference in 1991 on Food Standards, Chemicals
in Food, and Food Trade, requesting a scientific basis for the Codex standards. The conference
recommended that the Codex, in its norm-setting work on health and safety, place greater
emphasis on risk assessment. As a result, the Codex Alimentarius Commission identified risk
assessment of microbiological hazards in foods as a priority area of work. At its 32nd session
the Codex Committee on Food Hygiene (CCFH) identified a list of pathogen-commodity
combinations on which expert risk assessment advice is required (http://www.who.int/fsf/
mbriskassess/32thccfh.htm). In response, FAO and WHO are jointly launching a program
of work with the objective of providing expert advice on risk assessment of microbiological
hazards in foods to their member countries and to the Codex Alimentarius Commission.
As a consequence of the emerging international regulatory environment, microbial risk assessment
is now a common request in trade negotiations. Given that sanitary and phytosanitary measures
must be based on scientific evidence (or, where appropriate, scientific risk assessment), a formal
approach to the use of microbial risk assessment is required for the quantitative evaluation
of the microbial safety of foods
R i s k a s s e s s m e n t a n d n a t i o n a l f o o d s t a n d a r d s
Risk assessment and risk management underpin the government decision-making process
used for the protection of public health and safety in relation to the consumption of food.
It is important to understand these concepts when addressing the broader question about
acceptable levels of risk. In Australia, food standards allow the sale of a wide range of food
commodities, some of which may carry an inherent, albeit low, level of risk and, in this regard,
may be at odds with community expectations. In many cases, however, low levels of risk must
be balanced against the health benefit of a nutritious and varied diet. An informed debate about
acceptable levels of risk in relation to food can be achieved only through a greater awareness
of risk assessment and risk-management practices.
National food safety regulation is increasing in the degree of management complexity in many
countries. This increase is related to increased production volumes and product sophistication
and to changing consumer handling and consumption patterns. In addition, consumer
expectation has become progressively more demanding. Today, the public sometimes has virtually
unattainable expectations regarding the degree of safety that can be achieved through regulatory
action. Indeed, some consumers seem to desire 100% safety for many food products. Unfortunate-
7R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c e
Risk management is the field of decision-making, or at least its preparation. Its first objective
must be to safeguard health. Risk management appeals to the fields of technology, economy,
law, diplomacy and politics, particularly the regulation of public affairs (Anon. 2000a). Similarly,
in supporting risk-management decision-making, risk assessment will provide scientific support
to many disciplines at different levels of the food chain. Risk assessment can be applied at an
international level, at a national level, and at an industry or company level (see Figure 5).
R i s k a s s e s s m e n t a n d i n t e r n a t i o n a l f o o d s t a n d a r d s
As a result of food trade liberalisation, concern about the safety of imported food has grown.
The movement of ever-increasing quantities of food across borders has resulted in transnational
disease risks. Thus, the globalisation of the food trade and the open access to foreign markets
need to be accompanied by effective means of health protection for large international
populations. In the food sector, international regulatory instruments need to be integrated
with strengthened surveillance and monitoring (Käferstein et al. 1997).
Application of the Sanitary and Phytosanitary Measures Agreement, prescribed by the World
Trade Organisation (WTO), is designed to address these concerns (Vose 1998). Codex
Alimentarius Commission standards, guidelines, and recommendations are recognised as the
reference for national food safety requirements. Countries that are members of the WTO may
no longer be able to reject foods that meet Codex recommendations without providing
justification (Anon. 2000, Klapwijk et al. 2000).
6 B u r e a u o f R u r a l S c i e n c e s
R isk assessment in safe food produc tionRisk assessment in safe food production
Figure 5. Risk assessment continuum
Risk Assessment Doc.FA 11/7/01 3:13 PM Page 6
the three steps are considered separately, when developing microbial risk assessments
for food processes and HACCP design there are more typically a series of risk assessment/risk
management iterations. A process is assessed, the results interpreted, the process modified, and
the new risk assessed until the process provides an acceptable level of control.
So far the primary focus of risk assessment has been to consider risks associated with entire
industries and broad groups of products; in fact, some proponents feel that microbial risk
assessment should be limited to these broad evaluations. However, when dealing with an industry
whose processes and products are as diverse as those encountered with foods, any meaningful
translation of risk-assessment models into risk-management decisions will require individual
assessments of specific products and processes. Just as HACCP is only truly effective when
applied on a plant-specific basis, ultimately risk-assessment models need to be flexible enough
to allow the user to modify parameters to reflect the specific attributes of their products, processes
and facilities. Performing risk simulations for a standard or proposed food process gives an initial
assessment of the magnitude of the hazard and more directly relates the process to public health
goals. The use of simulation techniques represents an important paradigm shift in that hazard
assessments begin to address variability inherent in any process, product and pathogen.
Simulations can be used to determine if the focus of an HACCP plan needs to be on
improvement of the entire process or a single operation, or whether preventing a few extreme
combinations of factors from occurring will make a process safer. With information from risk
assessments, it should be much easier to establish quantitative values for critical limits to produce
the degree of stringency required, and then to design appropriate monitoring systems. Results
can also suggest how much abuse the process can withstand both before and after the product
leaves the manufacturer’s control. This can assist manufacturers in practising “due diligence”
in the design of their process and HACCP program.
S t r e n g t h s a n d l i m i t a t i o n s o f r i s k a s s e s s m e n t
It is clear that risk assessment is a valuable tool in helping us make public health decisions
in the food safety area. Risk assessment helps to organise information about risk in a useful
manner. It also characterises the nature and likelihood of harm to the public. It helps to define
the uncertainties and provides some level of comfort with the inferences that are made. And
it points out data gaps that can help to prioritise research needs.
But there are some weaknesses to the risk assessment process as well. Risk assessment has
its roots in toxicology and carcinogenicity studies, and its application to other disciplines poses
significant challenges. For food safety, one challenge relates to the fact that bacteria can multiply
and produce toxins as conditions change while food moves through the farm-to-table continuum,
unlike chemical, environmental, or toxicological contaminants.
In addition to the difficulties in applying risk assessment to pathogens, risk assessment is also
subject to two types of uncertainties; those related to data and natural variability, and those
associated with any assumptions that are required when directly applicable data are not available.
9R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c e
ly, given current technology and production capabilities, industry cannot guarantee that a given
unit of a food product will be totally free of hazards. Some residual risk always remains, even
though it may be quite small in magnitude. Recognition of the need for a more systematic
process has prompted the adaptation of risk-analysis techniques to the field of food regulation.
Food regulators have always informally assessed the human health risks that may be associated
with the handling and consumption of food products. The informal qualitative assessment
of risk has assisted managers in decision-making for many years. This assessment is effective
and will continue to be used by managers to enhance food safety. However, for major decisions
it is important to gather all of the pertinent information and to consider it in the decision-making
process. This includes both available data and the uncertainties associated with the information.
Risk assessment is the appropriate tool to objectively evaluate this information. This deliberate
and comprehensive approach is valuable for major concerns in order to consider all available
information that could influence a management decision. The risk-assessment procedures also
document which information was considered and the assessment process itself.
R i s k a s s e s s m e n t a n d i n d i v i d u a l f o o d c o m p a n i e s
The second step in hazard analysis is to conduct a risk assessment. The type of risk assessment
that is used in hazard analysis for HACCP is different from the typical health-risk assessments.
The risk that is of concern to the food industry is not the probability of exposure of the consumer
to the hazard as it is in epidemiological risk assessments. Industry is more concerned with the
probability of microbial growth, survival, or contamination in the product during the process,
and how this can influence the microbiological status of their product. Although those conducting
an HACCP study must keep in mind the associated risks at the farm and consumer levels, the
food-processing industry must primarily focus on those hazards that they can control. Thus,
in the production of food, efforts are concentrated on controlling the occurrence of a hazard
because, in many cases, the consequences are beyond the company’s control.
Food microbiologists are called upon daily to make decisions concerning both the quality and
safety of foods, optimising the dual needs to provide wholesome products while maintaining
high quality at the least possible cost. Various conceptual tools have been developed to help
microbiologists make decisions of this nature. The most widely recognised and used system
is HACCP, which focuses on identifying and controlling the key process steps most significantly
affecting the safe production of a food. However, as HACCP has become more widely adopted,
it has become evident that there are areas within this approach that could be strengthened
if microbiologists were better able to quantitatively link product attributes with public health
concerns. In particular, conducting the initial hazard analysis and establishing critical limits would
benefit from more quantitative means of assessing the risks associated with the hazard identified
for a food product.
The desire to better estimate the potential impact of issues relating to safety and quality has
stimulated interest in the development of quantitative risk-assessment techniques that would
allow the food industry to perform reliable risk analyses. Although in traditional risk analysis
8 B u r e a u o f R u r a l S c i e n c e s
Risk Assessment Doc.FA 11/7/01 3:13 PM Page 8
Q u a n t i t a t i v e r i s k a s s e s s m e n t
Quantitative food safety risk-assessment was initially applied for chemical hazards but is now
covering microbial hazards as well. There are some important differences in the nature of
toxicants and microbes that strongly affect the way in which risk assessments are carried out.
The principles of risk assessment are simple, consisting of four closely related steps permitting
a quantitative estimation of the risks associated with the consumption of a particular food
product. However, there are uncertainties, particularly in identifying hazards and in determining
dose-response relationships. Some causative agents of foodborne disease have yet to emerge
and be recognised. Dose-response relationships are weak points because reliable data are scarce.
This is especially true for certain sensitive groups.
Research is needed to determine the effect of infective dose in relation to the type of food and
the distribution of pathogens in a food product. Research is also needed to better understand
the critical assumptions involved in following the distribution and numbers of particular
pathogens throughout the food production and processing chain. The effect of individual
processing steps is often ill defined, and their inclusion into an HACCP plan can often lead
to arguments between processors and auditors. Increasingly, the safety of food will be based
on controlling all steps in the food production process. Such controls must be based on priorities
set after a proper risk assessment in order to be most effective.
Data assembled during the risk-assessment process is often modelled, and uncertainty and
variability scenarios tested, through mathematical simulations. A common method is Monte Carlo
analysis. The model can include a sensitivity analysis whereby the influence of assumptions can
be tested and the effect of corrective actions assessed. Critical knowledge gaps can be identified
and used to direct future research efforts. Quantitative risk assessment is described in Appendix 1.
E x p e r t p a n e l a n a l y s i s
Often there is a lack of available information to undertake an objective quantitative risk
assessment. The immediate alternative is to perform a qualitative assessment, the drawback being
that numbers will not be available to compare effects of remedial activities. As an interim solution,
several experts in the area can be asked to give their opinion on the different steps of the
process. A questionnaire could be used to ask the experts to rank effects. By averaging responses,
a semi-objective analysis will be achieved. This is sometimes used by scientists but is more
difficult for industry to undertake. Expert panel analysis is described in Appendix 2.
Q u e s t i o n n a i r e r a n k i n g t o o l
This method has been pioneered by Campden & Chorleywood Food Research Association
Group (CCFRA) in an industry guideline published in June 2000 (Voysey 2000). CCFRA
developed a “Risk Profile” questionnaire to cover all the steps involved in risk assessment.
The questionnaire includes 44 questions sorted in 14 sections, most including a five-point scoring
system. The questionnaire addresses all four areas of an objective quantitative risk assessment.
The questionnaire has been used as a starting point for the description in Appendix 3.
11R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c e
The ultimate risk assessment methodology is a scientific quantitative risk assessment (QRA).
A QRA requires much in the way of resources and particular expertise. It can take several years
to complete all the steps of a QRA, and it often involves international collaboration. It is probably
not feasible for industry to undertake a formal QRA in developing an HACCP program. However,
published QRA information can be used as a basis for assessing the effect of suggested critical
control point interventions in a production system.
A more expedient method to still objectively quantify risks is to use expert knowledge. A number
of experts are asked for their opinion in relation to steps in the process, and a composite picture
developed by the expert panel to complete the risk assessment.
At an industry level, a complex questionnaire has been developed with a scoring system
to assess relative risks and to prioritise necessary action.
A similar system is used in a spreadsheet model using a through-chain approach to calculate
a computerised risk-ranking score.
Finally, decision tree flow charts can be used to lead the risk assessor through a simple
qualitative approach of assessing risks. This is the most common way in industry to improve
on simple experience and gut feel in analysing hazards and their potential effect.
Figure 6. The selective use of risk-assessment tools by different participants in the food chain.
10 B u r e a u o f R u r a l S c i e n c e s
Quantitative Risk AssessmentExpert panel
Questionnaire Ranking
Government/Industry
Business
Decision TreeExperience/Gut feelProprietary models
Results/outcomes of industryrisk assessments should
provide knowledgefor food business
M e t h o d s f o r r i s k a s s e s s m e n tMethods for risk assessment
Risk Assessment Doc.FA 11/7/01 3:13 PM Page 10
13R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c e
I n t e r n a t i o n a l c a s e s t u d i e s
International case studies listed here follow the quantitative risk assessment
methodology and cover a range of product and microorganism combinations.
The studies have been summarised in Table 1 according to product area covered.
Each of the areas covered and the studies completed are presented briefly in the
following text.
Table 1. International quantitative risk-assessment case studies sorted according to product category covered.
Product Microorganism Country Reference
Egg and egg Salmonella spp. Canada Todd 1996
products Salmonella enteritidis USA Whiting and Buchanan 1997
Salmonella enteritidis USA Baker et al. 1998
Salmonella enteritidis International Ebel et al. 2000
Salmonella spp. International Fazil et al. 2000
Salmonella spp International Fazil et al. 2001
Ready-to-eat Listeria monocytogenes Canada Farber et al. 1996
food Listeria monocytogenes International Buchanan and Lindqvist 2000
Listeria monocytogenes International Ross et al. 2000
Listeria monocytogenes International Buchanan et al. 2001
Listeria monocytogenes USA Whiting and Long 2001
Bacillus cereus France Carlin et al. 2000
Clostridium botulinum France Carlin et al. 2000
Vibrio parahaemolyticusListeria monocytogenesVibrio spp.
Vibrio spp
USA
Sweden
International
International
Miliotis and Watkins 2000
Lindqvist and Westö 2000
Walderhaug and Bowers 2001
Depaola et al. 2001
Seafood
Salmonella spp.
Salmonella spp.
Salmonella spp.
Salmonella enteritidisCampylobacter spp.
UK
International
International
International
International
Brown et al. 1998
Fazil et al. 2000
Fazil et al. 2001
Kelly et al. 2000
Anderson et al. 2001
Poultry meat
Escherichia coli O157:H7
Escherichia coli O157:H7
EU
Canada
Dormont et al. 2000
Cassin et al. 1998Beef
Listeria monocytogenesListeria monocytogenesBacillus cereus
France
Canada
Netherlands
Bemrah et al. 1998
Farber et al. 1996
Notermans et al. 1997
Dairy
C o m p u t e r i s e d r i s k r a n k i n g t o o l
The risk assessment analysis seems ideally suited to using computerised tools; however, this
review only encountered one of those. This is a spreadsheet system developed at the University
of Tasmania (Ross and Sumner 2001). The spreadsheet asks 11 questions and, using a mix of
logarithmic and linear modelling, calculates a risk estimate for a given population to become ill
from a particular organism in a defined product. The spreadsheet is illustrated in Appendix 4.
D e c i s i o n t r e e f l o w c h a r t
This is the most common improvement to pure risk guessing. It takes the practitioner through
a few questions in a formalised decision tree structure. The benefit is that, rather than guess the
general risk involved in a process or for a particular hazard, it can be split up into components
and considered more carefully. An example is given in Appendix 5.
E x p e r i e n c e a n d g u t f e e l
In developing an HACCP plan, hazard analysis involves some sort of risk assessment
in order to prioritise development of critical control points and sample plans. In many cases
this is building on joint experience acquired by company staff and could be developed
in a round-table discussion format. This can work well in many companies; the big problem
is the lack of objectivity for the process to stand up to audit scrutiny. A more formal and
quantitative approach will facilitate the audit process.
I n t e r n a t i o n a l g u i d e l i n e s
• Codex Principles and Guidelines for the Conduct of Microbiological Risk Assessment
(CAC/GL-30 1999). ftp://ftp.fao.org/codex/standard/volume1b/en/GL_022e.pdf
• European Commission. Principles for the development of risk assessment of microbiological
hazards under directive 93/43/EEC concerning the hygiene of foodstuffs. Office for Official
Publications of the European Communities, Luxembourg (1997).
http://europa.eu.int/comm/food/fs/sc/scf/index_en.html
• Joint FAO/WHO Expert Consultation on Risk Assessment of Microbiological Hazards in Food
(WHO Headquarters, 15-19 March,1999).
http://www.who.int/fsf/mbriskassess/Consultation99/index.htm
• International Life Science Institute (ILSI) Revised framework for microbial risk assessment.
An ILSI Risk Science Institute Workshop Report, ILSI Press, Washington D.C. (2000).
http://www.ilsi.org/file/mrabook.pdf
12 B u r e a u o f R u r a l S c i e n c e s
R e p o r t s o n Q u a n t i t a t i v e R i s k A s s e s s m e n tReports on Quantitative Risk Assessment
Risk Assessment Doc.FA 11/7/01 3:13 PM Page 12
15R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c e
E g g s a n d e g g p r o d u c t s
Quantitative risk assessment model for Salmonella enteritidis
in pasteurised liquid eggs
One of the first complete microbial risk assessments to be published covered
the risk of Salmonella enteritidis being spread through home-made mayonnaise
made from pasteurised liquid eggs (Whiting and Buchanan 1997). Using
a ‘unit operations’ and stochastic simulation approach, data on the frequency
of pathogens in raw ingredients, predictive microbiology models for growth
and inactivation, and dose-response models for infectivity were integrated
to create a quantitative risk-assessment model. The risk assessment indicated
that pasteurisation provided sufficient consumer protection from a high incidence
of infected birds and from temperature abuse between the farm and the
egg breakers. However, scenarios showed how inadequate pasteurisation
temperatures and/or temperature abuse during storage lead to a hazardous
product. This dynamic risk model aids in the identification and setting
of critical control points and of assessing the impact of alterations to food
formulations or processes.
Salmonella enteritidis risk assessment—shell eggs
and egg products
The previous project was expanded in a joint study involving scientists from the
US Department of Agriculture, the Food and Drug Administration, the Centre
for Disease Control, and universities (Baker et al. 1998). The joint study covered
a farm-to-table microbial risk assessment of Salmonella enteritidis in shell
eggs and egg products. It summarises the risk-assessment process from the
development of a conceptual framework through the careful organisation
of information obtained from published scientific literature and unpublished
academic, government and industry sources, to the incorporation of available
data into a comprehensive quantitative model. The model illustrates the public
health effects associated with the consumption of Salmonella enteritidis-infected
shell eggs and egg products. According to the baseline egg products model the
probability is low that any cases of Salmonella enteritidis will result from the
consumption of pasteurised egg products. However, it was concluded that the
current US Food Safety and Inspection Service time and temperature regulations
do not provide sufficient guidance to the egg products industry for the large
range of products involved. Time and temperature standards based on the
amount of bacteria in the raw product, how the raw product will be processed,
and the intended use of the final product will provide greater protection to the
consumers of egg products.
Risk assessment of use of cracked eggs in Canada
In 1992, Agriculture and Agri-Food Canada amended its Egg Regulations
to restrict movement of Canada C eggs (cracked) to federally registered processed
14 B u r e a u o f R u r a l S c i e n c e s
egg stations for pasteurisation. This was questioned by egg producers and some
provinces on economic grounds. It was also in conflict with long-standing
practices of marketing eggs in some provinces to retail stores, bakeries,
restaurants and institutions or at the farm gate. In order to determine how
much of a risk these eggs were to human health, the Health Protection Branch
of Health Canada conducted a risk assessment (Todd 1996). On the basis of
outbreak data, Salmonella spp. were identified as the main hazard in these eggs.
Salmonellae may occasionally be present on shell eggs even after washing, and
any microorganism reaching the membranes can be transferred to an egg mixture
through breaking, and will rapidly grow under incorrect storage conditions.
A relative risk analysis showed that cracked eggs are 3 to 93 times more likely
than uncracked shell eggs to cause outbreaks. A probability of illness of 1
in 3 800 was derived from the 40 million cracked eggs produced in Canada and
not pasteurised and a probable 10 500 illnesses arising from these. Even though
it is not possible to precisely determine the risk of salmonellosis through cracked
eggs, this assessment indicated that there was enough of a concern to merit
a management strategy. Eight options for managing the risk were considered
and ranked for acceptability.
Salmonella in broilers and eggs
Codex is currently attempting to coordinate international efforts in the food risk
assessment area. Initial work on hazard identification, hazard characterisation
(Fazil et al. 2000) and exposure assessment (Ebel et al. 2000) of Salmonella spp.
and Salmonella enteritidis in eggs, respectively, has been completed. The two
projects were combined with a risk assessment of Salmonella spp. in broilers for
the final risk characterisation (Fazil et al. 2001). The risk characterisation initially
set out to understand how the incidence of human salmonellosis is influenced
by various factors during the agricultural phase of egg production, marketing,
processing, distribution, retail storage, consumer storage, meal preparation and
finally consumption. Such models are appealing because they enable the study
of the broadest range of intervention strategies. However, as the work progressed
it became evident that quantitative information available was not sufficient to
allow the construction of a full model. The model now used will be expanded
as further information becomes available.
R e a d y - t o - e a t f o o d
Health risk assessment of Listeria monocytogenes in Canada
Certain ready-to-eat foods are vulnerable to contamination and growth
of Listeria monocytogenes. A Canadian study presents the major steps used
in the formulation of a health-risk assessment for Listeria monocytogenes (Farber
et al. 1996). Data is given on the numbers of human listeriosis cases reported in
Canada along with the current Canadian regulatory policy on L. monocytogenes.
Since no direct human dose response data is available for L. monocytogenes,
Risk Assessment Doc.FA 11/7/01 3:13 PM Page 14
S e a f o o d
Listeria monocytogenes in salmon and rainbow trout
The objective of a Swedish study was to develop a quantitative risk-assessment
model in which the exposure and risk of acquiring listeriosis from consumption
of packaged smoked or gravad salmon and rainbow trout were estimated
(Lindqvist and Westö 2000). An Excel spreadsheet model was constructed
in which variables were represented by distributions based on surveys
of Listeria monocytogenes in these food products, and on demographic
and consumption data.
Public health impact of Vibrio parahaemolyticus
in raw molluscan shellfish
A draft risk assessment was produced by the U.S. Food and Drug Administration
to characterise the public health impact associated with consumption of raw
oysters harbouring pathogenic Vibrio parahaemolyticus (Miliotis and Watkins
2000). The risk assessment structures knowledge of the microorganism
in a systematic manner and includes sophisticated mathematical models to
estimate consumer exposure and dose-response relationships with the organism.
Vibrio spp. in seafood
Codex has also initiated work on Vibrio spp. in seafood. Preliminary findings
only on hazard characterisation (Walderhaug and Bowers 2001) and exposure
assessment (Depaola et al. 2001) have been presented for discussion.
P o u l t r y m e a t
Comparative risk of salmonellosis from chicken products
In the United Kingdom, models have been developed according to the Codex
principles to provide a quantitative risk assessment of salmonellosis involving
frozen poultry products (Brown et al. 1998). This model-based QRA takes into
account three types of information: occurrence and distribution of the agent,
sensitivity of populations to infection (e.g. normal or susceptible), and the effect
of cooking (in the factory or home) on concentration of the agent and hence
risks of infection after product consumption.
Salmonella in broilers and eggs
Codex has initiated international work on Salmonella in poultry meat. Initial
work on hazard identification, hazard characterisation (Fazil et al. 2000) and
exposure assessment (Kelly et al. 2000) of Salmonella spp. in broiler products
has been completed. The projects were combined with a risk assessment of
Salmonella in eggs for the final risk characterisation (Fazil et al. 2001). As the
work progressed it became evident that quantitative information available was
not sufficient to allow the construction of a full model. The model now used
will be expanded as further information becomes available.
17R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c e16 B u r e a u o f R u r a l S c i e n c e s
a flexible dose-response model called the Weibull-Gamma model was used for
the hazard characterisation step. Paté was used as a prototype for the exposure
assessment step. The dose response output was combined with some predictive
growth modelling assuming an initial exposure of a single cell for food stored
at 4 and 8˚C. Storage of paté at 4˚C for more than 35 days resulted in a rapidly
increasing risk for the high-risk population. Storage at 8˚C produced a similar risk
after about 13 days.
Listeria monocytogenes in ready-to-eat foods
Codex has initiated an international assessment of the risk of L. monocytogenes
in ready-to-eat foods with initial work on hazard identification, hazard
characterisation (Buchanan and Lindqvist 2000) and exposure assessment
(Ross et al. 2000) completed. The risk assessment was concluded with the risk
characterisation component (Buchanan et al. 2001). Considering the resources
available the risk assessment was limited to selected ready-to-eat foods
representing various classes of product characteristics. The risk of these foods
serving as a vehicle for human food-borne listeriosis was estimated.
Relative public health risk from Listeria monocytogenes
in ready-to-eat foods
The U.S. Food and Drug Administration, the U.S. Department of Agriculture
and the Centre for Disease Control conducted an assessment of the relative risk
of listeriosis associated with various types of ready-to-eat foods (Whiting and
Long 2001). This draft risk assessment details the current state of knowledge
about this foodborne disease, and includes sophisticated models developed
to estimate exposure and dose-response relationships, and the variability
inherent in these estimates. A distinction is made between L. monocytogenes
infections limited to mild, flu-like symptoms (referred to as listerial gastroenteritis)
and those that are severe and life-threatening (referred to as listeriosis). This risk
assessment only addresses listeriosis.
Risk assessment of spore-forming pathogenic bacteria
in cooked chilled vegetable foods
A Flair-Flow Europe project aim to estimate the risk of food-borne disease from
hazardous spore-forming bacteria in cooked-chilled foods containing vegetables
(Carlin et al. 1999). Data from a literature review undertaken on hazard
identification and characterisation were used to identify dose-response
information curves for some of the hazardous spore-forming bacteria and their
toxins. Quality of the data was relatively poor and sparse. Spore-forming bacteria
detected in a range of processed products and raw vegetables belonged mainly
to the Bacillus genus. Clostridium spp. were also present but in very low
numbers. A non-isothermal measuring method indicated that the heat resistance
of spore-forming bacteria can vary greatly and validation of heat resistance in real
foods is, therefore, necessary.
Risk Assessment Doc.FA 11/7/01 3:13 PM Page 16
General Listeria monocytogenes
Meat Inspection
Healy 2001
Pointon et al. 2000
Grains General Richardson 2000
Human listeriosis from consumption of soft cheese made
from raw milk
A French study identified microbial hazards in soft cheese made from raw milk
(Bemrah et al. 1998). Quantification of the resulting public health risk was
attempted within the framework of the Codex Alimentarius Commission 1995
approach to quantitative risk assessment, using Monte Carlo simulation software.
Quantitative data could only be found for Listeria monocytogenes. The complete
process of cheese making was modelled, from milking to consumption.
A risk assessment study of Bacillus cereus present in pasteurised milk
A Dutch study looked at the heat resistance of Bacillus cereus, its potential
pathogenic character, the capability to grow in milk and reported diseases upon
consumption of dairy products (Notermans et al. 1997). It concluded that the
organism should be considered as hazardous in pasteurised milk.
D o m e s t i c s t u d i e s
Australian case studies listed here use a combination of methods for the
risk assessment. Some include a full quantitative risk assessment of specific
product/microorganism combinations while others use a quantitative approach
to provide an initial risk-ranking of a range of products in an industry.
The studies have been summarised in Table 2 according to product covered.
Table 2. Australian risk-assessment case studies of different products or product categories.
Plant products General Richardson 2000
Escherichia coli O157:H7
Shiga toxin Escherichia coli
Lammerding et al. 1999a
Lammerding et al. 1999dBeef
19R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c e
Campylobacter spp. in broiler chicken
Codex has also initiated work on Campylobacter spp. in broiler chickens.
Preliminary findings only on hazard identification and characterisation, and
exposure assessment (Anderson et al. 2001), have been presented for discussion.
B e e f
Oral exposure of humans to the BSE agent: Infective dose
and species barrier
Many risk assessments have been performed in relation to the pathogenicity
of the bovine spongiform encephalopathy (BSE) agent. The European
Commission Scientific Steering Committee has produced an opinion on the
infective dose and species barrier of oral exposure of humans to the BSE agent
(Dormont et al. 2000). This document, although not following the risk-assessment
model, includes an analysis of the risk to humans of the entry of BSE-infected
tissues into the food chain.
Escherichia coli O157:H7 in ground beef hamburgers
A Canadian study modelled the human health risk associated with Escherichia
coli O157:H7 in ground beef hamburgers (Cassin et al. 1998). Two models were
developed; the first was intended to describe the behaviour of the pathogen
from the production of the food through processing, handling, and consumption
to predict human exposure. The exposure estimate was then used as input to
a dose-response model to estimate the health risk associated with consuming
food from the process. The efficacy of three risk-mitigation strategies was
evaluated by modifying the values of the predictive factors and comparing
the new predicted risk. The average probability of illness was predicted to be
reduced by 80% under a hypothetical mitigation strategy directed at reducing
microbial growth during retail storage through a reduction in storage temperature.
D a i r y p r o d u c t s
Health risk assessment of Listeria monocytogenes in Canada
Soft cheese as a high-risk food in terms of listeriosis infection was used
as prototype in risk-assessment models (Farber et al. 1996). Using disappearance
data for cheese and 100g as a typical serving, the data suggested an average
of 102 servings per capita, per year in Canada. An equation to calculate the
average probability of acquiring human listeriosis in Canada from soft and
semi-soft cheese consumption was formulated. Computations derived from
this equation indicated substantial consistency between reported data and
assumptions of the risk-assessment model. The total annual estimated cost
of listeriosis illnesses and deaths in Canada was estimated to be between
C$11.1 and 12.6 million.
18 B u r e a u o f R u r a l S c i e n c e s
Product Microorganism Reference
Clostridium perfringens Lammerding et al. 1999cReady-to-eat
General
General
Listeria monocytogenes
Walsh 1999; Ross and Sanderson 2000
Sumner 2001
Healy 2001
Miliotis and Watkins 2000
Seafood
Dairy General
General
Ross 2001a
Safefood Production NSW 2000
Smallgoods Escherichia coli O157
Listeria monocytogenes
Lammerding et al. 1999b
Sumner 2001
Risk Assessment Doc.FA 11/7/01 3:13 PM Page 18
Listeria monocytogenes in selected foods
A partnership between Australia New Zealand Food Authority, the New Zealand
Ministry of Health, Food Science Australia and the New Zealand Institute
of Environmental Science and Research Limited (ESR) to explore risks involving
Listeria monocytogenes in selected foods has been initiated (Healy 2001).
The study is currently concentrating efforts in the seafood industry since
zero tolerance legislation for the organism in cooked seafood products is being
introduced. The aim is to provide regulators, industry and consumers with
a comprehensive and transparent strategy, which identifies the general principles
to minimise risk to Australian and New Zealand consumers of a food-borne
Listeria infection. The strategy development will take into account a number
of national and international initiatives in the management of Listeria.
The project has five modules:
– Assessment of current Listeria management strategies
– Surveillance and epidemiology
– Resource identification
– Risk assessment and management framework development
– Strategy document
B e e f
Escherichia coli O157:H7 in fresh ground Australian beef:
Issues of equivalence
Escherichia coli O157:H7 remains an important pathogen to many of Australia’s
trading partners. This is particularly true of the United States, which is our largest
customer for frozen boxed beef destined for the hamburger market. Because
of the increased awareness of this particular pathogen a model was developed
to consider the concept of equivalence between food production systems
(Lammerding et al. 1999a). The study, incorporating the farm-to-fork continuum,
estimated the risk to the North American population of E. coli O157:H7
through the consumption of hamburgers manufactured from Australian meat.
This case study illustrates the potential application of risk assessment models
in determining equivalence as has been proposed under the Sanitary and
Phytosanitary (SPS) Agreement of the World Trade Organisation. The case study
highlights the potential application of risk assessment in trade disputes based
on food safety.
Shiga toxin-producing E. coli (STEC) in ground Australian beef:
Process improvement
There has been a large amount of data gathered on the prevalence of E. coli
O157:H7 in meat. However, other serotypes have been implicated in food-borne
outbreaks as well and these strains appear to be more important in Australia.
21R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c e
R e a d y - t o - e a t f o o d
Clostridium perfringens in Australian foodservice operations
Debate has recently arisen over the need for stricter cooling regimens after the
cooking step in roast beef manufacturing. Preliminary analysis of growth data
for C. perfringens during cooling conducted in collaboration between Food
Science Australia, the University of Tasmania, and Health Canada pinpointed
the lag time as one of the most important parameters in determining the amount
of growth of the organism (Lammerding et al. 1999c). The case study highlighted
the importance of data collection and predictive microbiology to support
scientifically valid processing guidelines. The primary focus of the model
was to investigate the impact that food service has on the risk following
both a well-controlled process as well as a process that may have experienced
some deviations.
S e a f o o d p r o d u c t s
Identification and prioritisation of hazards across the supply chain
This activity was commissioned by SafeFood Production NSW as a two-step
process involving Food Factotum Pty Ltd (Walsh 1999) and University of
Tasmania (Ross and Sanderson 2000) to serve as a basis to develop a food
safety scheme for the seafood industry. Raw finfish intended for cooking has
few associated hazards. The growth in raw fish consumption, however, may
have introduced a greater risk from parasitic infection and histamine poisoning.
Vacuum or modified atmosphere packaging (MAP) of raw fish and its more
common use for smoked fish introduces the risk from Clostridium botulinum
growth and the production of toxin and listeria growth, respectively. Cooked
seafood can be contaminated during the cooling and packaging processes. The
most hazardous seafood group is the bivalve molluscs, particularly when eaten
raw or undercooked. For each of the hazards identified as a high priority, the
University of Tasmania assessed the likelihood and severity of the hazard. Ten
hazards were ranked in the following priority order: viruses in bivalve molluscs,
algal biotoxins in bivalve molluscs, ciguatera toxin in fish, histamine in fish,
vibrio species in seafood, enteric bacteria in shellfish, L. monocytogenes in ready-
to-eat smoked fish products, botulism in vacuum packaged ready-to-eat seafood
products, parasites in seafood and mercury in fish.
Risk assessment tools for the seafood industry
A study for Seafood Services Australia to develop a simple model for risk
assessment in the seafood industry has recently been completed (Sumner 2001a).
The project supported the development of a computerised model (Ross and
Sumner 2001) and its application among regulators and operators in the
seafood industry.
20 B u r e a u o f R u r a l S c i e n c e s
Risk Assessment Doc.FA 11/7/01 3:13 PM Page 20
Risk assessment of products made from unpasteurised goat
and sheep milk
A study supported by Safefood Production NSW has been completed to provide
the background for a risk-based Food Safety Scheme for the Goat and Sheep
Milk industries to be introduced by regulation in early 2001 (Anon. 2000c).
P l a n t p r o d u c t s
Plant product scoping study
A study by Food Science Australia for Safefood Production NSW was undertaken
to set priorities for further activities in the plant area based on an objective
assessment of food safety risks (Richardson 2000). This is considered a scoping
study for future work and includes qualitative risk assessments of a number of
plant products. The risks have been ranked from high to low depending on the
risk for initial contamination (high for edible product growing in soil) and usual
preparation methods (high for consuming raw).
G r a i n s
Risk management activities in the grains industry
A project was recently initiated by the Grains Research and Development
Corporation and undertaken by the University of Tasmania to set priorities
for risk-management activities in the grains industry (Ross 2001b). Results
are not yet available.
P i g c a r c a s e p o s t m o r t e m i n s p e c t i o n
Foodborne hazards in abnormal and normal tissues of pig carcases
A systematic quantification of food-borne hazards in abnormal and normal
tissues of pig carcases was undertaken to provide a risk-based assessment of the
effectiveness of traditional organoleptic meat inspection (Pointon et al. 2000).
23R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c e
In this study the risk of illness from the consumption of hamburgers
contaminated with pathogenic STEC was estimated using dose-response
information obtained for Shigella (Lammerding et al. 1999d). The model
developed looked at all stages of production beginning at the processing
of cattle and extending to the consumption of ground beef. The model
incorporates several parameters that are specific to Australian production,
in particular the prevalence and concentration of STEC in Australian cattle.
As well as providing an estimate of the risk to the Australian population, the
model focuses on possible process improvements using various hypothetical
risk mitigation strategies (i.e. decontamination, irradiation, consumer awareness,
better control at retail etc.).
S m a l l g o o d s
Escherichia coli O157 in fermented meat products in Australia
This case study is a process risk model for the manufacture of salami, although
the effect of raw material quality on the final risk estimate is also investigated
(Lammerding et al. 1999b). The process is modelled from receipt of raw materials
to final consumption and the risk to the Australian population estimated. The
case study incorporates aspects of predictive microbiology and presents data
generated from other research in the form of a mathematical model describing
the reduction in E. coli O157:H7 as a function of the process parameters. The
model identified E. coli O157:H7 concentration in the raw material and a high
pH after fermentation as being positively correlated to the final health risk,
while fermentation time and storage temperature were identified as important
negatively correlated processing parameters (i.e. increasing these values
decreased the final risk).
Listeria monocytogenes in smallgoods
A study has also recently been initiated by Meat and Livestock Australia to
quantify risks involving Listeria monocytogenes in smallgoods (Sumner 2001b).
Results are not yet available.
D a i r y
Priorities for risk management activities in the dairy industry
A project being undertaken by the University of Tasmania for the Dairy Research
and Development Corporation to set priorities for risk management activities
in the dairy industry has recently been initiated (Ross 2001a). Results are not
yet available.
22 B u r e a u o f R u r a l S c i e n c e s
Risk Assessment Doc.FA 11/7/01 3:13 PM Page 22
24 B u r e a u o f R u r a l S c i e n c e s
G a p b e t w e e n s c i e n c e a n d p r a c t i c e
Because of the recent evolution of this area there is a substantial amount of scientific activity
but less activity in the areas of practical use and application of the methodology. Some of the
scientific through-chain work has been developed in a modularised fashion to allow industry
to apply the results for their part of the chain. Typically, practical applicability has been lacking.
S u g g e s t e d a c t i o n s
1. Support potential research that provides linkages between risk assessment and the practical
application of these findings within industry sectors.
L a c k o f u s e f u l t o o l s
Some risk assessment models developed are often very complex and difficult to communicate.
Considerable expertise is required to translate the models into practical food industry actions.
S u g g e s t e d a c t i o n s
1. Evaluate some of the risk assessment tools already available.
2. Develop practical tools that apply to industry, which can be used by HACCP practitioners.
L a c k o f p r a c t i c a l i n d u s t r y e x a m p l e s
Most of the work so far in the area has been through scientific institutions building full
through-chain industry models or governments developing models to set priorities for policy
and regulations.
S u g g e s t e d a c t i o n s
1. Industry case studies that apply risk assessment to HACCP-based management systems.
2. Explore in-house risk-assessment work. within large food companies.
25R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c e
L a c k o f c o o r d i n a t i o n
A gap analysis was undertaken to identify issues and suggest actions to improve the utilisation
of risk assessment in HACCP-based industry quality systems. The review found the following
points worthy of further consideration:
C o o r d i n a t i o n e f f o r t s
Within Australia there seems to be fragmented efforts in pursuing qualitative and quantitative
risk assessments.
S u g g e s t e d a c t i o n s
1. Creating a risk assessment clearing house for Australian information.
2. Organise a conference/meetings to identify the current status of risk assessment
within Australia.
3. Ensure that Australia is tapped into the Codex work
L a c k o f k n o w l e d g e
Risk assessment methodology has progressed in the chemical area but less so in the
microbiological area. In recent years, general information on the methodology for microbial
risk assessment was published and terminology for the work further developed. This information
is still to filter through to industry and the practicality of the published information tested.
S u g g e s t e d a c t i o n s
1. Organise hands-on industry workshops to disseminate information.
2. Develop an industry manual for quantitative microbial risk assessments.
L a c k o f i n f o r m a t i o n s o u r c e s
It is currently difficult to get general and specific information related to international risk-
assessment activities. There are some dedicated international websites covering this type
of information. There are also international risk associations dealing with food topics among
many other topics.
S u g g e s t e d a c t i o n s
1. Conduct an international review of risk assessment activities.
G a p a n a l y s i sGap analysis
Risk Assessment Doc.FA 11/7/01 3:13 PM Page 24
Buchanan, R. & Lindqvist, R. (2000) Hazard identification and hazard
characterization of Listeria monocytogenes in ready-to-eat foods. Food and
Agriculture Organisation, Rome.
Buchanan, R, Lindqvist, R., Ross, T., Todd, E., Smith, M. & Whiting, R. (2001)
Risk assessment of Listeria monocytogenes in ready-to-eat foods. Food and
Agriculture Organisation, Rome.
Buchanan, R. L. & Whiting, R. C. (1998) Risk assessment: a means for linking HACCP
plans and public health. Journal of Food Protection, 61, 1531-1534.
Carlin, F., Girardin, H., Peck, M. W., Stringer, S. C., Barker, G. C., Martinez,
A., Fernandez, A., Fernandez, P., Waites, W. M., Movahedi, S., van Leusden,
F., Nautam M, Moezelaar, R., Torre, M. D. & Litman, S. (2000) Research on factors
allowing a risk assessment of spore-forming pathogenic bacteria in cooked chilled
foods containing vegetables: a FAIR collaborative project. International Journal
of Food Microbiology, 60, 117-135.
Cassin, M. H., Lammerding, A. M., Todd, E. C., Ross, W. & McColl, R. S. (1998)
Quantitative risk assessment of Escherichia coli O157:H7 in ground beef hamburgers.
International Journal of Food Microbiology, 41, 21-44.
Clark, A.J. & Brinkley, T. (2001) Risk management for climate, agriculture and policy.
Bureau of Rural Sciences, Commonwealth of Australia, Canberra.
Depaola, A., Karunasagar, I., Osaka, K., Sumner, J. & Walderhaug, M. (2001)
Exposure assessment of Vibrio spp. in seafood. Food and Agriculture Organisation,
Rome.
Dormont, D., Budka, H., Kretzschmar, H., Pocchiari, M., Sommerville, R., Ostrhaus,
A., Bradley, R. & Schlatter, J. (2000) Oral exposure of humans to the BSE agent:
Infective dose and species barrier. European Commission Scientific Steering
Committee, Brussels.
Ebel, E. D., Kasuga, F., Schlosser, W. D. & Yamamoto, S. (2000) Exposure assessment
of Salmonella enteritidis in eggs. Food and Agriculture Organisation, Rome.
Fabiansson, S.U. & Cunningham D.C. (2000) Evolution of Australian food quality
systems. Bureau of Rural Sciences, Canberra.
Farber, J. M., Ross, W. H. & Harwig, J. (1996) Health risk assessment of Listeria
monocytogenes in Canada. International Journal of Food Microbiology, 30, 145-156.
Fazil, A., Lammerding, A. M., Morales, R. A., Vicari, A. S. & Kasuga, F. (2000)
Hazard Identification and Hazard Characterization of Salmonella in broilers
and eggs. Food and Agriculture Organisation, Rome.
27R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c e26 B u r e a u o f R u r a l S c i e n c e s
Anderson, S., Bak Christensen, B., Fazil, A., Hartnett, E., Lammerding, A., Nauta,
M., Paoli, G. & Rosenquist, H. (2001). Hazard identification, hazard characterisation
and exposure assessment of Campylobacter spp. in broiler chicken. Food and
Agriculture Organisation, Rome.
Anon. (1983) Risk assessment in the federal government: managing the process.
National Research Council, Washington (DC).
Anon. (1996) Framework for the assessment and management of food-related
health risks. Australia New Zealand Food Authority, Canberra.
Anon. (1999) Principles and guidelines for the conduct of microbiological risk
assessment. CAC/GL-30 (1999) Codex Alimentarius Commission, Rome.
Anon. (2000a) First report on the harmonisation of risk assessment procedures.
European Commission Health & Consumer Directorate, Brussels.
Anon. (2000b) International animal health code. Office International des Epizooties,
Paris.
Anon. (2000c) Risk assessment of products made from unpasteurised goat and sheep
milk. SafeFood Production NSW, Sydney.
Baker, A. R., Ebel, E. D., Hogue, A. T., McDowell, R. M., Morales, R. A., Schlosser,
W. D. & Whiting, R. C. (1998) Salmonella enteritidis risk assessment—shell eggs and
egg products. Food Safety and Inspection Service, Washington, DC.
Bemrah, N., Sanaa, M., Cassin, M. H., Griffiths, M. W. & Cerf, O. (1998) Quantitative
risk assessment of human listeriosis from consumption of soft cheese made from raw
milk. Preventive Veterinary Medicine, 37, 129-145.
Berends, B. R. & van Knapen, F. (1999) An outline of a risk assessment-based system
of meat safety assurance and its future prospects. Veterinary Quarterly, 21, 128-134.
Brown, M. H., Davies, K. W., Billon, C. M., Adair, C. & McClure, P. J. (1998)
Quantitative microbiological risk assessment: principles applied to determining the
comparative risk of salmonellosis from chicken products. Journal of Food Protection,
61, 1446-1453.
R e f e r e n c e sReferences
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McNab, W. B. (1998) A general framework illustrating an approach to quantitative
microbial food safety risk assessment. Journal of Food Protection, 61, 1216-1228.
Miliotis, M. & Watkins, W. (2000) Draft risk assessment on the public health
impact of Vibrio parahaemolyticus in raw molluscan shellfish. U.S Food and
Drug Administration, Center for Food Safety and Applied Nutrition, Washington.
Morales, R. A. (1998) Microbial risk assessment, economics, and food safety.
Journal of the American Veterinary Medical Association, 213, 1746-1749.
Notermans, S., Dufrenne, J., Teunis, P., Beumer, R., te Giffel, M. & Peeters-Weem,
P. (1997) A risk assessment study of Bacillus cereus present in pasteurised milk.
Food Microbiology, 14, 143-151.
Notermans, S. & Mead, G. C. (1996) Incorporation of elements of quantitative
risk analysis in the HACCP system. International Journal of Food Microbiology,
30, 157-173.
Pointon, A. M., Hamilton, D., Kolega, V. & Hathaway, S. (2000) Risk assessment
of organoleptic postmortem inspection procedures for pigs. The Veterinary Record,
146, 124-131.
Potter, M. E. (1996) Risk assessment terms and definitions. Journal of Food
Protection, Supplement, 6-9.
Richardson, K. (2000) Plant product scoping study. Food Science Australia,
Rodricks, J. V. (1999) Food Safety Policy, Science, and Risk Assessment: Strengthening
the Connection, Washington DC. National Academic Press, p 25-27.
Ross, T. (2001a) Personal communication on risk assessment in the dairy industry.
Ross, T. (2001b) Personal communication on risk assessment in the grains industry.
Ross, T. & Sanderson, K. (2000) A risk assessment of selected seafoods in NSW.
School of Agricultural Science, University of Tasmania, Hobart.
Ross, T. & Sumner, J. (2001) A simple spreadsheet-based food safety risk assessment
tool. International Journal of Food Microbiology, Submitted.
Ross, T., Todd, E. C. & Smith, M. (2000) Exposure assessment of Listeria
monocytogenes in ready-to-eat foods. Food and Agriculture Organisation, Rome.
Sumner, J. (2001a) Personal communication on seafood project.
Sumner, J. (2001b) Personal communication on smallgoods project.
29R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c e
Fazil, A., Lammerding, A. M., Kasuga, F., Ebel, E., Kelly, L., Anderson, W. & Snary,
E. (2001) Risk characterisation of Salmonella in broilers and eggs. Food and
Agriculture Organisation, Rome.
Healy, M. (2001) Personal communication on risk assessment of Listeria
monocytogenes in food products.
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a transnational challenge. Emerging Infectious Diseases, 3, 503-510.
Kaplan, S. (1997) The words of risk analysis. Risk Analysis, 17, 407-417.
Kelly, L., Anderson, W. & Snary, E. (2000) Exposure assessment of Salmonella spp.
in broilers. Food and Agriculture Organisation, Rome.
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Protection, Supplement, 24-30.
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origin. Journal of the American Veterinary Medical Association, 209, 2055-2056.
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in Europe: the next decade. International Journal of Food Microbiology, 58, 223-230.
Lammerding, A. M. & Fazil, A. (2000) Hazard identification and exposure assessment
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58, 147-157.
Lammerding, A. M., Fazil, A., Paoli, G. M., Desmarchelier, P. & Vanderlinde,
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Issues of equivalence. Meat and Livestock Australia, Sydney.
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P. (1999b) Escherichia coli O157 in fermented meat products in Australia. Meat
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P. (1999c) A quantitative risk assessment model for C. perfringens in Australian
foodservice operations. Meat Research Corporation, Sydney.
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P. (1999d) Shiga toxin-producing E. coli in ground beef manufactured from
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Lindqvist and Westö (2000) Quantitative risk assessment for Listeria monocytogenes
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of Food Microbiology, 58, 181-196.
28 B u r e a u o f R u r a l S c i e n c e s
Risk Assessment Doc.FA 11/7/01 3:13 PM Page 28
H a z a r d i d e n t i f i c a t i o n
The identification of biological, chemical, and physical agents, capable of causing
adverse health effects, that may be present in a particular food or group of food.
Hazard identification is the first step of the risk-assessment process. It gives a qualitative
indication of the potential hazards arising from consumption of a particular food product.
For chemical agents, hazard identification establishes potential adverse health effects in
humans associated with exposure to a particular substance, a ranking of the likelihood of such
effects occurring and the certainty or uncertainty associated with such effects. Chemical agents
include intentionally introduced chemicals, inadvertent contaminants and naturally occurring
toxicants. Examples could be food additives; residues of pesticides and other agricultural
chemicals; residues from veterinary drugs; chemical contaminants from any source; and
natural toxins, such as mycotoxins and ciguatoxin.
For microbial agents, hazard identification consists of identification of the micro-organisms
and microbial toxins of concern. Information on potential hazardous micro-organisms can be
obtained from surveys of the microbial composition of raw materials and from epidemiological
surveillance of food-borne infections and intoxications. Analysis is complicated by the
enormous genetic variety shown even within identified species of micro-organisms and
their different reactions to food and processing conditions.
E x p o s u r e a s s e s s m e n t
The qualitative and/or quantitative evaluation of the likely intake of biological,
chemical and physical agents via food as well as exposure from other sources
if relevant.
After identification of the hazard, information is needed on the amount contained in the food
product, and on consumption patterns. Estimates of dietary intakes of food additives, residues
of pesticides and veterinary drugs and contaminants require information on the consumption
of relevant foods and the concentration of the chemical of interest in those foods. In general,
exposure estimates are based on known or anticipated dietary information for particular foods
together with an estimate of the level of the chemical in particular commodities.
For microbiological agents, information is needed on their numbers or the level of bacterial
toxin and the distribution in food components that are intended for processing. Such
information provides the basis for determining the effects of processing and product
composition on the level of contamination of the end-product at the time of consumption.
31R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c e
Todd, E. C. (1996) Risk assessment of use of cracked eggs in Canada. International
Journal of Food Microbiology, 30, 125-143.
Troutt, H. F., Gillespie, J. & Osburn, B. I. (1995) Implementation of HACCP program
on farms and ranches. In HAACP in meat, poultry and fish processing; A. M. Pearson
& T. R. Dutson, Eds.; Blackie Academic & Professional: Glasgow, 1995; pp 36-57.
van Gerwen, S. J., te Giffel, M. C., van’t Riet, K., Beumer, R. R. & Zwietering,
M. H. (2000) Stepwise quantitative risk assessment as a tool for characterization
of microbiological food safety. Journal of Applied Microbiology, 88, 938-951.
Vose, D. J. (1998) The application of quantitative risk assessment to microbial food
safety. Journal of Food Protection, 61, 640-648.
Voysey, P. A. (2000) An introduction to the practice of microbiological risk assessment
for food industry application. Campden & Chorleywood Food Research Association
Group, Chipping Campden.
Walderhaug, M. & Bowers, J. (2001) Hazard characterisation of Vibrio spp.
in seafood. Food and Agriculture Organisation, Rome.
Walsh, P. (1999) Identification and prioritisation of hazards across the supply chain.
Food Factotum, Tasmania.
Whiting, R. C. & Buchanan, R. L. (1997) Development of a quantitative risk
assessment model for Salmonella enteritidis in pasteurized liquid eggs. International
Journal of Food Microbiology, 36, 111-125.
Whiting, R. C. & Long, W. (2001) Draft Assessment of the Relative Risk to Public
Health from Foodborne Listeria monocytogenes Among Selected Categories of Ready-
to-Eat Foods. FDA/Center for Food Safety and Applied Nutrition, Washington.
30 B u r e a u o f R u r a l S c i e n c e s
A p p e n d i x 1 — Q u a n t i t a t i ve r i s k a s s e s s m e n tAppendix 1– Quantitative risk assessment
Risk Assessment Doc.FA 11/7/01 3:13 PM Page 30
For chemicals, risk characterisation might be expressed as a margin of safety between the
acceptable level of intake of an additive or contaminant, based on the known hazard, and the
known level of human exposure via the diet. When no threshold is evident, a more qualitative
estimate of risk is necessary.
For microbial agents, risk characterisation is usually a qualitative description of the
circumstances under which a food may be contaminated at a level that would potentially pose
a risk to human health. It may include reference to a sampling plan, which should conform to
the microbiological limits.
In principle, if the exposure estimate is reliable and appropriate and the dose-response data
of good quality and covers this exposure range, risk characterisation is a quite straightforward
process. However, this is often not the case and the degree of confidence in the final
estimation of risk depends on the variability and uncertainty factors identified in previous
steps. The two components, variability and uncertainty, describing the degree of reliability
of the risk estimate, should be clearly and distinctly described. The variability is the effect
of chance and is a function of the system, whereas uncertainty is the assessor’s lack
of knowledge about a given parameter and may include parameter uncertainty, model
uncertainty and scenario uncertainty. The separate effect of variability and uncertainty
on the risk estimate should be made clear.
33R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c e
Several techniques, such as surveillance tests, storage tests and microbiological challenge
testing, can be used for this assessment. Predictive microbiology is also a useful tool for
determining effects of factors that control the safety of food products.
In the case of microbiological agents, there is an added dimension of micro-organism
replication under particular processing and storage conditions. For chemical agents, too,
there are additional considerations; for example, it is necessary to give proper consideration
to the role of degradation products and metabolites in either increasing or decreasing specific
adverse effects.
H a z a r d c h a ra c t e r i s a t i o n ( o r d o s e - r e s p o n s e r e l a t i o n s h i p )
The qualitative and/or quantitative evaluation of the nature of the adverse health
effects associated with the hazard.
Hazard identification is primarily a question of identifying the effects that are considered
as adverse. Hazard characterisation is centred on the quantification of these effects so that
a dose-response relationship can be established. Such a definition equally applies to chemical
and microbiological risk assessment. However, it has to be realised that the response of a
human population to a pathogen is highly variable. The characteristics of the pathogen will
affect its pathogenicity and virulence. The number of microbes that come into contact with
a host and overcome the natural barriers will determine infection. The general health or
immune status of the host may determine translation of infection into illness and its severity.
The attributes of the vector (in particular, in the case of a food product) can also influence
the outcome. The likelihood that any specific individual may become ill due to an exposure
to a microbial pathogen is dependent on the integration of the pathogen, the host and the
matrix effects. In addition to characterising the nature of the adverse health effects, analysing
and evaluating these interactions based on collating information on the pathogen, the host
and the matrix, are keys to microbiological hazard characterisation.
R i s k c h a ra c t e r i s a t i o n
The qualitative and/or quantitative estimation, including attendant uncertainties,
of the probability of occurrence and severity of known or potential adverse
health effects in a given population based on hazard identification, hazard
characterisation and exposure assessment.
Risk characterisation brings together information gained from previous steps and provides
a practical estimate of risk for a given population. Risk-management strategy is then
formulated on the basis of this determination.
32 B u r e a u o f R u r a l S c i e n c e s
Risk Assessment Doc.FA 11/7/01 3:13 PM Page 32
E x t e r n a l c r o s s - r e f e r e n ce
Expert opinion should be cross-referenced against the opinions of other experts
and the body of published evidence (the scientific model of a risk). This can be
developed repeatedly throughout the course of the risk analysis.
I n t e g ra t i o n
The role of the analyst is to integrate a broad range of evidence, targeting it towards
the analysis criterion. This is an iterative process that requires careful questioning
of the evidence, re-assessment and finally the formation of an evidence-based
judgment.
Co m m u n i c a t i o n
Such judgment needs to be communicated to decision-makers. An appraisal
of the precision in the analysis and the research methodology is also important.
35R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c e34 B u r e a u o f R u r a l S c i e n c e s
Documenting expert opinion on risk properties uses a structured research
methodology to minimise subjective biases. The role of the risk analyst is to
go beyond collecting expert evidence to developing a critical evaluation. This
description is based on the methodology published by Clark and Brinkley (2001).
It uses some or all of the following checks and balances:
E x p e r t c r e d i b i l i t y
To establish the credibility and qualifications of potential experts to provide opinion
relating to the specific risk. This may involve understanding the potential biases
an expert has in providing evidence.
Co n t ex t
To provide enough contextual information about the risk-management process
to the expert without highlighting the specific implications of any decisions.
This can maintain the independence of the expert.
I n f o r m a t i o n g a t h e r i n g
The experts can be asked to provide opinion:
• casually,
• in published reports,
• in formal interviews, or
• in a meeting of experts (comparative analysis).
Each of these has different checks and balances that help to minimise biases; for
example, published scientific work has been through a high level of critical review
by other experts in the field.
I n t e r n a l c r o s s - r e f e r e n ce
Experts can be asked to re-state or clarify their opinions at a later stage and this can
be cross-referenced with the original statement by the analyst. This accounts for
emotional or other biases.
A p p e n d i x 2 — E x p e r t o p i n i o nAppendix 2 – Expert opinion
Risk Assessment Doc.FA 11/7/01 3:13 PM Page 34
7. How uncertain is this estimate?
Data from the specific food/microbe combination or similar sets.
Score
Sub-score occurrence
Exposure assessment (effect of processing/decontamination)
8. What is the effect of storage before processing
on the hazard contamination level?
Use in-house data and literature data as appropriate.
Document the data separately for future reference.
Score
9. What is the effect of processing and decontamination
steps on the contamination level of the micro-organism?
Consider initial numbers and the impact of processing and decontamination.
All assumptions must be clearly stated. Where there is no data, the presence
or survival of the hazard at a hazardous dose at consumption must be assumed.
Score
10. What is the combined effect of storage and processing
on toxin formation?
Consider toxin concentration as it relates to organism numbers
and environmental conditions conducive of toxin formation.
Score
11. What is the uncertainty of this estimate?
High levels of uncertainty may be associated with this type of assessment,
making it more-or-less useless—for example if the product is safe with high
uncertainty. Default conditions offering the highest level of consumer protection
should be used.
Score
Sub-score processing/decontamination
Exposure assessment (potential for re-contamination)
12. What is the frequency of re-contamination of the product
after processing?
This can include an estimate only, but it is better if the score is based
on real data and calculation of the actual frequency.
Score
37R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c e36 B u r e a u o f R u r a l S c i e n c e s
This text and questionnaire contain the elements of a risk assessment and indicate the data
needed for it to be undertaken. It is based on a guideline published by Campden & Chorleywood
Food Research Association Group in 2000. Because many companies wishing to undertake risk
assessment will not have ready access to experts, values provided in this appendix represents the
likely ranges for the key determinants of risk. When using this questionnaire it is essential to
remember that the risk estimate will only be as good as the data used in the assessment. This
questionnaire will allow the user to recognise the features of their process and product exerting
the biggest influence on the level of risk, to distinguish between the seriousness of various
hazards, and to visualise the risk profile of the product under examination.
Going through the risk profile considerations, it can be seen that each step contributing to the
score can be rated from low to high and each ranking score is associated with a number from
1 (low) to 5 (high). When all the questions have been answered the ranking score is made up
of values between 1 and 5. The higher the value, the higher the risk. For infectious pathogens
the maximum score is 75 and for toxin-forming pathogens the maximum score is 10 with
a maximum quality score of 55.
Hazard Identification (descriptive part – no scoring)
1. What type of product and product characteristics Name:
are covered by this risk assessment? Type:
2. What pathogenic organisms can be associated with the product? Names:
3. Microorganism specifically covered by this risk assessment? Name:
4. Can the microorganism act through a pre-formed toxin? Yes/No
Please note the box placement in relation to the scoring category:
Exposure Assessment (occurrence of the pathogenic microorganism)
5. What is the frequency of contamination of the raw materials
making up the product?
Use in-house data and literature data as appropriate. Also consider
toxin formation.The conditions for toxin production need to be
known to assess this. Document the data for future reference.
Score
6. What is the contamination level range found
in the raw materials?
Use in-house data and literature data as appropriate. Document the data
for future reference.
Score
1 – never: 0
2 – very low frequency: 1/1000
3 – low frequency: 1/100
4 – high frequency: 1/10
5 – always: 1/1
1 – 0-10 cells/g
2 – 0-102 cells/g
3 – 0-103 cells/g
4 – 0-104 cells/g
5 – >104 cells/g
Quality Profile Toxin Score General Profile
1 – accurate data on relevant microbe/food
2 – accurate data on similar microbe/food
3 – quantitative general data on similar
microbe/food
4 – qualitative general data on similar microbe/food
5 – opinion/default, no hard data
1 – 0-10 cells/g
2 – 0-102 cells/g
3 – 0-103 cells/g
4 – 0-104 cells/g
5 – >104 cells/g
1 – inactivation: at least 6-log decrease
2 – inactivation: between 3 and 6-log
3 – no changes: survival
4 – slow growth: less than 3-log increase
5 – rapid growth: at least 3-log increase
1 – at least 6-log inactivation, no toxin
2 – between 3 and 6-log inactivation, no toxin
3 – no changes: survival, no toxin production
4 – low growth (<3-log), low chance of toxin
5 – rapid growth (>3-log), high chance of toxin
1 – accurate data on relevant microbe/food
2 – accurate data on similar microbe/food
3 – quantitative general data on similar microbe/food
4 – qualitative general data on similar microbe/food
5 – opinion/default, no hard data
1 – never: 0
2 – very low frequency: 1/1000
3 – low frequency: 1/100
4 – high frequency: 1/10
5 – always: 1/1
A p p e n d i x 3 — Q u e s t i o n n a i r e r a n k i n g t o o lAppendix 3 – Questionnaire ranking tool
Risk Assessment Doc.FA 11/7/01 3:13 PM Page 36
19. What is the likelihood of toxin formation during storage?
This question has to consider both the likely number of organisms
(previous question) and the impact of storage conditions on toxin formation.
Score
20. What is the uncertainty of this estimate?
Score
Sub-score storage
Exposure assessment (open shelf life to be considered only when relevant )
21. Is the product intended as single use or multi-use where
22. What is the effect of open shelf-life storage on the level
of microorganism?
This includes storage of the product throughout the chain
from production to consumption.
Score
23. What is the uncertainty of this estimate?
Score
24. What is the likelihood of growth and toxin formation
during open shelf-life?
This question has to consider both the likely number of organisms
(previous question) and the impact of storage conditions on toxin formation.
Score
25. What is the uncertainty of this estimate?
Score
Sub-score
39R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c e
13. What is the likely concentration of the pathogen
from re-contamination after processing?
This can include an estimate only, but it is better if the score
is based on real data and calculation of the actual level.
Score
14. What is the uncertainty of this estimate?
Score
Sub-score potential for re-contamination
Exposure assessment (packaging)
15. What is the frequency of re-contamination at or after packaging?
This can include an estimate only, but it is better if the score is based on real data
and calculation of the actual frequency. Whether the product is packaged before
or after possible decontamination will be significant for this estimate.
Score
16. What is the likely level of re-contamination at or after packaging?
This can include an estimate only but it is better if the score is based on real data
and calculation of the actual level. Whether the product is packaged before
or after possible decontamination will be significant for this estimate.
Score
17. What is the uncertainty of this estimate?
Score
Sub-score
Exposure assessment (storage)
18. How does the level of the microorganism change during storage?
This includes storage of the product throughout
the chain from production to consumption.
Score
38 B u r e a u o f R u r a l S c i e n c e s
1 – 0-10 cells/g
2 – 0-102 cells/g
3 – 0-103 cells/g
4 – 0-104 cells/g
5 – >104 cells/g
1 – accurate data on relevant microbe/food
2 – accurate data on similar microbe/food
3 – quantitative general data on similar
microbe/food
4 – qualitative general data on similar microbe/food
5 – opinion/default, no hard data
0 – not applicable
1 – never: 0
2 – very low frequency: 1/1000
3 – low frequency: 1/100
4 – high frequency: 1/10
5 – always: 1/1
0 – not applicable
1 – 0-10 cells/g
2 – 0-102 cells/g
3 – 0-103 cells/g
4 – 0-104 cells/g
5 – >104 cells/g
0 – not applicable
1 – accurate data on relevant microbe/food
2 – accurate data on similar microbe/food
3 – quantitative general data on similar microbe/food
4 – qualitative general data on similar microbe/food
5 – opinion/default, no hard data
1 – inactivation: at least 6-log decrease
2 – inactivation: between 3 and 6-log
3 – no changes: survival
4 – slow growth: less than 3-log increase
5 – rapid growth: at least 3-log increase
1 – never
2 – unlikely
3 – possible
4 – likely
5 – certain
1 – accurate data on relevant microbe/food
2 – accurate data on similar microbe/food
3 – quantitative general data on similar
microbe/food
4 – qualitative general data on similar microbe/food
5 – opinion/default, no hard data
Single use Go to 26
Multi-use Go to 22
1 – inactivation: at least 6-log decrease
2 – inactivation: between 3 and 6-log
3 – no changes: survival
4 – slow growth: less than 3-log increase
5 – rapid growth: at least 3-log increase
1 – accurate data on relevant microbe/food
2 – accurate data on similar microbe/food
3 – quantitative general data on similar microbe/food
4 – qualitative general data on similar microbe/food
5 – opinion/default, no hard data
1 – at least 6-log inactivation, no toxin
2 – between 3 and 6-log inactivation, no toxin
3 – no changes: survival, no toxin production
4 – low growth (<3-log), low chance of toxin
5 – rapid growth (>3-log), high chance of toxin
1 – accurate data on relevant microbe/food
2 – accurate data on similar microbe/food
3 – quantitative general data on similar microbe/food
4 – qualitative general data on similar microbe/food
5 – opinion/default, no hard data
Risk Assessment Doc.FA 11/7/01 3:13 PM Page 38
32. What is the uncertainty of this estimate?
Score
Sub-score food intake
Hazard characterisation
33. Who are the likely consumer groups for the product?
Examples include families/babies/elderly
34. Nominate a sub-group at risk!
Nominate each at-risk group for a separate analysis should the sensitivity differ.
If there is only one homogenous consumer group with similar sensitivity,
one analysis will suffice.
35. What is the severity of the hazard?
The sensitivity of each group should be considered or that of the most sensitive
consumers should be used for a single assessment.
Score
36. What is the hazardous level of the microorganism
covered by this risk assessment?
The generally accepted infectious dose, boundaries of toxin formation
or toxin persistence should be used.
Score
37. What is the uncertainty of this estimate?
There will be high uncertainty with this type of risk estimate, it will only
be generally valid and take account of the consumers with ’text-book’ sensitivity.
Score
Sub-score hazard characterisation
Risk characterisation
Risk profile – general score Min 14 Max 75
Risk profile – toxin score Min 5 Max 25
Information quality profile Min 11 Max 55
41R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c e
Exposure assessment (consumer usage and preparation)
26. What is the effect of end-use preparation
and product usage on the level of the hazard?
Assessment should be based on use or portion size instructions,
unless there are indications that other practices can significantly
alter risk or dose (e.g. under-cooking). Likely abuse should
be considered.
Score
27. What is the uncertainty of this estimate?
Score
28. What is the effect of end-use preparation and product
usage on toxin level and production?
Score
29. What is the probability of toxin presence at the point
of consumption?
Score
30. What is the uncertainty of this estimate?
Score
Sub-score consumber usage & preparation
Exposure assesssment (food intake)
31. What is the likely quantity of the food consumed by a customer
on a specified occasion or over a period of time?
Score
40 B u r e a u o f R u r a l S c i e n c e s
1 – inactivation: at least 6-log decrease
2 – inactivation: between 3 and 6-log
3 – no changes: survival
4 – slow growth: less than 3-log increase
5 – rapid growth: at least 3-log increase
1 – accurate data on relevant microbe/food
2 – accurate data on similar microbe/food
3 – quantitative general data on similar microbe/food
4 – qualitative general data on similar microbe/food
5 – opinion/default, no hard data
0 – not applicable
1 – eliminate
2 – reduce
3 – unchanged
4 – slight increase
5 – large increase
0 – not applicable
1 – never: 0
2 – very low frequency: 1/1000
3 – low frequency: 1/100
4 – high frequency: 1/10
5 – always: 1/1
0 – not applicable
1 – accurate data on relevant microbe/food
2 – accurate data on similar microbe/food
3 – quantitative general data on similar microbe/food
4 – qualitative general data on similar microbe/food
5 – opinion/default, no hard data
1 – very low intake: 0 - 10 g
2 – low intake: 10 - 50 g
3 – medium intake: 50 - 100 g
4 – high intake: 100 - 200 g
5 – very high intake: >200 g
1 – accurate data on relevant microbe/food
2 – accurate data on similar microbe/food
3 – quantitative general data on similar microbe/food
4 – qualitative general data on similar microbe/food
5 – opinion/default, no hard data
Groups:
Groups:
1 – mild symptoms, prompt recovery
2 – mild symptoms for a few days
3 – generally mild symptoms, hospitalisation
4 – severe symptoms, hospitalisation, deaths
5 – several deaths
1 – > 10,000 cells
2 – high minimum dose: 1000 – 10 000 cells
3 – minimum dose: 100 – 1000 cells
4 – low minimum dose: 10 – 100 cells
5 – very low minimum dose: 0 – 10 cells
1 – accurate data on relevant microbe/food
2 – accurate data on similar microbe/food
3 – quantitative general data on similar microbe/food
4 – qualitative general data on similar microbe/food
5 – opinion/default, no hard data
Risk Assessment Doc.FA 11/7/01 3:13 PM Page 40
43R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c e
This is a simple tool for food safety risk-assessment developed by Ross and Sumner
(2001) to assist decisions by food safety risk managers. The tool is in spreadsheet
software format and embodies established principles of food safety risk-assessment,
i.e. the combination of probability of exposure to a food-borne hazard, the
magnitude of hazard in food when present, and the probability and severity
of outcomes that might arise from that level and frequency of exposure.
The tool requires the user to select from qualitative statements and/or to provide
quantitative data concerning factors that will affect the food safety risk arising
from a specific food product, and specific hazard during the steps from harvest
to consumption. The spreadsheet converts the qualitative inputs into numerical
values and combines them with the quantitative inputs in a series of mathematical
and logical steps using standard spreadsheet functions. Those calculations are used
to generate indices of the public health risk.
The model underpinning the tool is a gross simplification of the harvest-to-
consumption pathway, but the tool offers a quick and simple means of comparing
food-borne risks from diverse products and is useful for ranking and prioritising
risks from diverse sources. It can be used to screen food-borne risks and identify
those requiring more rigorous assessment. It also serves as an aid to structured
problem-solving and can help to focus attention on those factors in food production,
processing, distribution and meal preparation that most affect food-safety risk and
that may be the most appropriate targets for risk-management strategies.
The risk model user interface, using Australian populations as an example, is shown
on the following page. Users mouse-click on their choice in each list box or provide
numerical values as required. As choices are made and values entered, the risk
estimates are automatically recalculated.
42 B u r e a u o f R u r a l S c i e n c e s
A p p e n d i x 4 — C o m p u t e r i s e d r i s k r a n k i n gAppendix 4 – Computerised risk ranking
Risk Assessment Doc.FA 11/7/01 3:13 PM Page 42
Acceptable Level Dangerous Level
Description of Food Safety Problem and ContextWhat is the specific hazard to be explored?
Name:
Review criticalcontrol points
NEVEROFTEN
OK whenprocess is
under control
Make sureprocess is
under control
ExposureAssessment
Will end-use preparation reducethe hazard to acceptable
levels?
SOMETIMESALWAYS
Process undercontrol
Review criticalcontrol points
ExposureAssessment
Will process steps (critical controlpoints) reduce the hazard
to acceptablelevels?
LOW
Less stringentprocess required
Review criticalcontrol points
HIGH
ExposureAssessment
What is the likelihoodof contamination of raw
materials or process?
SEVEREMILD
Less stringentprocess required
Seek expertadvice
HazardIdentification
What are the consequencesand severity of adverse
effects?
HIGHLOW
Process undercontrol
Seek expertadvice
RiskCharacterisation
What is the integrated risk measureof hazard characterisation and
exposure assessment?
LOW
LOW
LOW
LOW
LOW
No Yes Don’t know
0 1 Find out
Mild Major Severe
0.1–0.5 0.5–0.8 0.8–0.1
Low Medium High
0.1–0.5 0.5–0.8 0.8–1
Often Sometimes Never
0 0.5 1
Range between 0 (low) and1 (high) risk (when multiplying
with 0 the answer is 0 whichindicates an absolute control point).
(number of CCPs as appropriate)
DON’T KNOWNO
Move tonext hazard
Seek expertadvice
HazardIdentification
Is the agent capable of causingadverse health effects?
LOW
Semi-Quantitative Analysis
Risk Estimate
1
2
3
CCP
1
4
0
0
Always
0
0
1
1
Sometimes
1
1
0.1–0.9
0.1–0.9
Often
0.1–0.9
0.1–0.9
X
X
X
X
X
Figure 7. Decision tree flow chart (to the left is a structured way to arrive at a qualitative risk estimate; below is an attempt to undertake a semi-quantitative risk estimate—the numbers in each row should be multiplied to arrive at the risk estimate number. When a range is given estimate specific number).
45R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c e
A decision tree is a structured way of evaluating risks by considering the different
components of risk assessment. The complexity increases further down the tree
when multiple influences are considered. Figure 7 (overleaf) is an attempt to
produce a possible decision tree covering the four areas of risk assessment.
One form should be completed for each identified hazard. The left-hand side
covers a qualitative approach with weighting of the responses at the end in the risk
characterisation. The more responses that end up to the left, the more acceptable
the risk. The right-hand side allows for a scoring system to be used. The numbers
should be multiplied to end up with an overall score. When multiplying with zero
the risk is negligible. By introducing multiple critical control points the risk can be
further reduced. Instead of a fixed scoring system, a nominated number between
the end points can be used.
The decision tree is a draft only and should be developed further. Microbiological
growth during storage or before consumption has not been included but could be
added by multiplying with numbers greater than one to increase the risk.
44 B u r e a u o f R u r a l S c i e n c e s
A p p e n d i x 5 — D e c i s i o n t r e e f l o w c h a r tAppendix 5 – Decision tree flow chart
Risk Assessment Doc.FA 11/7/01 3:13 PM Page 44
Useful literature
47R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c e
Web information
Australia:
Australian Institute of Food Science and Technology http://www.aifst.asn.au
Food Science Bureau (AFGC) http://www.foodsciencebureau.com.au
‘Food Australia’ magazine http://www.foodaust.com.au
Supermarket to Asia http://www.supermarkettoasia.com.au
Food Connect Australia http://www.foodconnect.com.au
Food Info Australia (AFFA) http://www.affa.gov.au/foodinfo
Australia New Zealand Food Authority http://www.anzfa.gov.au/
Food Safety Information Council http://www.safefood.net.au
Food Law and Policy Australia http://www.ausfoodnews.com.au/flapa
Australian Institute of Health and Welfare http://www.aihw.gov.au
CSIRO http://www.csiro.au
International:
Institute of Food Technologists http://www.ift.org
Foodborne Illness Education Center http://www.nal.usda.gov/fnic/foodborne/risk.htm
US Government Food Safety Web Site http://www.foodsafety.gov
(President’s Council on Food Safety)
Center for Food Safety and Applied Nutrition (USFDA) http://vm.cfsan.fda.gov
International food Information Council http://www.ificinfo.health.org
Risk Communication Network http://www.uea.ac.uk/env/cer
(Centre for Environmental and Risk Management)
National Environmental Health Association http://www.neha.org
World Health Organisation (WHO Food Safety Programme) http://www.who.int/fsf/
FoodNet Canada http://foodnet.fic.ca
National Food Safety Database, University of Florida, USA http://www.foodsafety.org
Asian Food Information Centre http://www.afic.org
46 B u r e a u o f R u r a l S c i e n c e s
Microbial Food Contamination Charles L Wilson & Samir Droby
(editors)
CRC press, 2001
http://www.crcpress.com
Food Toxicology William Helferich & Carl K Winter
(editors)
CRC press, 2001
http://www.crcpress.com
Fundamental Food
Microbiology (second edition)
Bibek Ray CRC press, 2001
http://www.crcpress.com
Natural Toxicants in Food David H Watson (editor) CRC press, 2001
http://www.crcpress.com
Interdisciplinary Food
Safety Research
Neal H Hooker & Elsa A Murano
(editors)
CRC press, 2001
http://www.crcpress.com
Environmental Contaminants
in Food
Colin Moffat & Kevin J Whittle (editors) CRC press, 2001
http://www.crcpress.com
Food Chemical Safety
Contaminants, vol 1
David Watson (editor) CRC press, 2001
http://www.crcpress.com
Food Chemicals Codex, fourth
edition, CRCnetBase 2000
Institute of Medicine (editors) CRC press, 2001
http://www.crcpress.com
HACCP in the Meat Industry Martyn Brown (editor) CRC press, 2001
http://www.crcpress.com
EU Food law, A Practical Guide Kaarin Goodburn (editor) CRC press, 2001
http://www.crcpress.com
The Microbiological Safety and
Quality of Food – Two Volumes
Barbara M Lund, Tony C Baird-Parker,
and Grahame W Gould (editors)
Aspen Publishers
Email: macpetty@zip.com.au
International Standards
for Food Safety
Naomi Rees, David Watson (editors) Aspen Publishers
Email: macpetty@zip.com.au
Food Protection Report (monthly newsletter) Pike & Fisher Inc, Maryland, USA
http://www.pf.com
Food Microbiology Newsletter Institute of Food Technologists & The
American Society for Microbiolog
http://www.ift.org/divisions/food_micro/
Title Author(s) Publishe
A p p e n d i x 6 — F u r t h e r r e a d i n gAppendix 6 – Further reading
Risk Assessment Doc.FA 11/7/01 3:13 PM Page 46
49R i s k A s s e s s m e n t i n F o o d S a f e t y P o l i c y a n d P r a c t i c e
BSE bovine spongiform encephalopathy
CCFH Codex Commission on Food Hygiene
CCFRA Campden & Chorleywood Food Research Association Group
Codex Codex Alimentarius Commission
CRC Cooperative Research Centre
FSIS US Food Safety and Inspection Service
HACCP hazard analysis critical control point
hazard any adverse agent; an agent with the potential to cause harm
ILSI International Life Science Institute
MAP modified atmosphere packaging
Monte Carlo analysis statistical simulation method
QRA quantitative risk assessment
risk likelihood of harm and severity of impact
SPS Agreement Sanitary and Phytosanitary Agreement
STEC Shiga-toxin producing Escherichia coli
Weibull-Gamma model flexible dose-response model
WHO World Health Organisation
48 B u r e a u o f R u r a l S c i e n c e s
G l o s s a r yGlossary
Risk Assessment Doc.FA 11/7/01 3:13 PM Page 48
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