BASS 2019 - Evaluating Surface Contamination - James Kapin.pdf · BASS 2019 - Evaluating Surface Contamination James Kapin, MPH, CIH [email protected] 619-990-5955 2 XYZ BioNanoPharmaX

BASS 2019 - Evaluating Surface Contamination

James Kapin, MPH, CIHwww.actenviro.com [email protected] 619-990-5955 1

How Clean is Clean?

Evaluating Removable Indoor Contamination

James Kapin, MPH, CIH

Manager of EM Services

ACTenviro

www.actenviro.com

[email protected]

619-990-5955BASS 2019 - Evaluating Surface Contamination 1

ABC Shooting Range

• 20,000 ft2 indoor shooting range

– Operated for 15 years

– Converting to Daycare/Pre-School

• What are we concerned about?

• What do we need to do?

BASS 2019 - Evaluating Surface Contamination 2

http://www.actenviro.com/

mailto:[email protected]



XYZ BioNanoPharmaX

• 5,000 ft2 Lab-based R&D

– 15 employees, Lab-scale use of solvents, acids, bases and 2

chemical fume hoods

– Business relocating to New Jersey, new start-up moving in



• (and who is we, anyway?)


Chatham Bros. Drum and Barrel

• 13 Acre Site

– Formerly used for waste oil recycling & solvent blending

– Benzene, PCB, TCE in soil vapor and groundwater



• (and who is we, anyway?)




Surface Decon.– Why do we care?

• Protect General Public?

• Protect Current Workers?

• Protect Future Workers?

• Protect Property Owner?

• How do different stakeholders affect our decisions?


Protect From What?


Reactivity?

Corrosivity?

Toxicity?

Flammability?

◦ Typically concerned Metals,

Pesticides, PBTs

NO!

NO!

NO!

YES!



Toxicity

• “All substances are poisons…the right dose differentiates a poison from a remedy” – Inhalation

– Dermal

– Ingestion

• Acute toxicity

• Chronic toxicityBASS 2019 - Evaluating Surface Contamination 7

-The Encyclopedia of Earth

Items to Consider at Contaminated Facilities:• What are the chemicals of concern?

• Who is likely to be affected

• What action (if any) need to be taken to characterize contamination?

• What actions (if any) should be taken to remove contamination (clean, demo, etc.)

• What actions (if any) should be taken to evaluate decontamination effectiveness?

• What regulations (if any) apply?

• HOW CLEAN IS CLEAN???– (there are several different approaches!)




How Clean is Clean:

“Hazardous Waste” Approach

The Hazardous Waste Approach• Apply regulatory hazardous waste values to

measured levels of surface contamination.– TTLC, STLC

– RCRA TCLP

– RCRA listed (e.g. F003)

• The good news:– We know these numbers!

– We have a clear regulatory framework (or do we?)

– This what we do!

– Decon activities frequent driven by environmental regulators




If all you have is a hammer…..


Everything looks like a nail!

The Hazardous Waste ApproachUnfortunately:

• Haz waste standards do not apply!– Is it waste! Is entire item contaminated, or just the surface?

– Haz Waste standards(i.e. TCLP) can only be used for haz waste determination

– (and don’t get me started about mis-use of F codes!)

• Cannot convert µg/wipe to µg/kg!– Mass per unit area cannot convert to mass per unit volume (or mass) without

more assumptions!

– Weight % of contaminant on wipe is NOT representative of weight % on substrate!

• OELs in mg/m3 (or ppm) cannot be converted (directly) to m2 (or ft2 or 100cm2)!




How Clean is Clean:

“Zero Tolerance” Approach

• Methamphetamine Contaminated Property Cleanup Act of 2005(AB 1078)– CA HSC 6.9.1 Section 25400.16

• Established (among other items) a re-occupancy level of 0.1 µg/100cm2

– Based on LOD

– No background

– Not “natural

• Any Problems?– We’ll come back to this!

Scenario #1




How Clean is Clean:

“Comparative” Approach

Scenario #2 • Wave Solder (leaded solder)

• 8 CCR 5198 (h)(1) –– “All surfaces shall be maintained as free as

practicable of accumulations of lead”

– ???

• “Comparative” standard– Removable contamination compared to

“clean” areas

– Applies to Pb, As, Cd and other metals

• Intended to protect workers




Problems with “Occurrence” Stds.

• Can be poorly defined

• What is the “dose”?

• Can be overly protective

• May not be protective enough?

• “Occurrence” approaches focus on Hazard

– Are there any risk-based approaches?


How Clean is Clean:

“Regulatory” Approach



DOE Berylium Standard• Berylium:

– Strong & Light

– X-ray Transparent, Neutron Reflector/ Moderator

– Highly Toxic - CBD

• DOE 10 CFR Part 850 CBD Prevention– “housekeeping” (internal) level = 3 µg/100cm2

– “release” (public) level = 0.2µg/100cm2

• ”Empirical” levels:– Achievable; didn’t seem to cause problems at relevant facilities e.g.

Rocky Flats

• No exposure scenario modeling or similar


HUD Lead Levels

• Guidelines for the Evaluation and Control of Lead-

Based Paint Hazards in Housing (2012 Edition)

– Bare floor = 40 µg/ft2 = 4.3 µg/100cm2

– Explicitly residential

• Only applicable to Pb


• Based on blood lead levels of

exposed children

– “Kind of” risk-based



How Clean is Clean:

“OEL Based” Approach

Scenario #3 – Fab Facilities• Use wide variety of potential hazards:

– Corrosives, Reproductive hazards (photoresists

– Metals

• Many sites used an “IH-based” approach– Arsenic TLV = 0.01 mg/m3

– At 20 m3/day, “allowable” exposure is 0.2 mg

– Can be used as maximum contamination for a given area (typically 100 cm2).

– “Allowable” As contamination is 0.2 mg/100 cm2

• Incorporated into OSHA Tech. Manual (2014)

• OELs apply to inhalation – can this be used for other routes?




Cal/OSHA MBOCA Std.

• Cal-OSHA established wipe sample level for MBOCA (4,4'-Methylenebis(2-Chloroaniline)) in 8 CCR 5215(c)(2)(C)– "Accessible surfaces which employees are likely to contact

…shall not exceed 100 µg MBOCA per 100 cm2 of surface.”

– “… the average of at least five wipe samples shall be used; if one sample exceeds the mean by a factor of 10 or more, it will be rejected as not being representative.”

• Allegedly the 100 µg/100 cm2 derived from PEL (10 µg/m3) * 10 m3.


Scenario #4 – Solar Cell Mfg.

• Cadmium Telluride (CadTel) process

– Significant mfg benefits, Can be significantly dirty!

• BNL Alternative IH-based approach

– BNL IH75190 2011 Surface Wipe Sampling

Procedure

• “Housekeeping”, “Release” levels for many

metals

– Widely used for internal guidance and facility decon




The 2011 BNL Approach:


• Levels for metals set by ratio:

–𝐷𝑂𝐸 𝑅𝑒𝑙𝑒𝑎𝑠𝑒 𝐿𝑒𝑣𝑒𝑙

𝑂𝑆𝐻𝐴 𝐵𝐸 𝑃𝐸𝐿=

𝑀𝑒𝑡𝑎𝑙 𝑅𝑒𝑙𝑒𝑎𝑠𝑒 𝐿𝑒𝑣𝑒𝑙

𝑀𝑒𝑡𝑎𝑙 𝑃𝐸𝐿 𝑜𝑟 𝑇𝐿𝑉 𝑖𝑛 µg/m3

–0 .2µ𝑔/100𝑐𝑚2

2µ𝑔/𝑚3 = 0.1 (𝑛𝑒𝑣𝑒𝑟𝑚𝑖𝑛𝑑 𝑡ℎ𝑒 𝑢𝑛𝑖𝑡𝑠!)

– Metal Release Level = TLV or PEL in µg/m3 * 0.1 (per 100cm2)

• Arsenic TLV = 10 µg/m3

– BNL As Free Release Level = 1 µg (per 100cm2)

• Cadmium TLV = 10 µg/m3 (total) – BNL Cd Free Release Level = 1 µg (per 100cm2)

• Current (6/23/17) BNL approach uses the “OEL” approach – (similar to MBOCA)

• Are we risk-based yet!

How Clean is Clean:

“Risk Based” Approach



• A risk-based approach!

• Based on EPA Risk Assessment Guidance for Superfund (RAGS)– Residential Exposure assumptions

– EPA guidance for residential pesticide exposure used for settled dust assessment

– based on ingestion, dermal contact with dust

– Established for 22 contaminants (metals and others)

• Be careful what you ask for though!– Dose Rate =

[(EThard*FTSShard*CSLhard)+(ETsoft*FTSSsoft*CSLsoft)]*SA*FQ*SE/BW

Scenario #5 – WTC Clean-up


Dose Rate =

([(EThard*FTSShard*CSLhard)+(ETsoft*FTSSsoft*CSLsoft)]*SA*FQ*SE/BW)/RfD

• ET = Exposure Time (hr/d)

• FTSS = Fraction Transferred from Surface to Skin (unitless fraction)

• CSL = Contaminant Surface Load (:g/cm2 )

• SA = Surface Area (cm2 /event)

• FQ = Frequency of hand to mouth events (events/hr)

• SE = Saliva Extraction factor (unitless fraction)

• ET = Exposure Time (hr/d)

• BW = Body Weight (kg)

• RfD – Reference Dose– EPA, 2001a. Science Advisory Council for Exposure. Policy Number 12 on Recommended Revisions to

the Standard Operating Procedures (SOPs) for Residential Exposure Assessments. Rev. February 22, 2001

• “For carcinogens, LADD is calculated by summing daily doses (PDR) over ages 1 to 31 and then averaging over a lifetime of 70 years.”

• “Dose rates were estimated based on a number of assumptions—for example, the fraction of dust residues that can be transferred to the skin, daily skin loads, mouthing behaviors for different age groups, and dissipation of surface loading over time.”




Description Notes Units Default

RFd EPA reference dose varies by substance

mg/kg-

day 0.0003

BW Body Weight

EPA Exposure Factors Handbook

(1989) kg 70

SAo Surface Area, expsoed hands


(1989) m2 0.084

MF

Fraction expossed area contacted by

mouth

Risk assess asumption -

conservative

amount/

day 0.5

CE Skin Contact Efficiency Risk assess asumption none 0.5

AFo G-I absorption Factor


conservative none 1

EF Exposure factor 12/24 hrs, 250/365 days, 40/70 yrs none 0.2

ED Exposure Duration Risk assess assumption none 0.5

SAd

Surface area, exposed hand, forearm,

head


(1989) m2 0.316

AFd Dermal Absorption factor


conservative none 0.01

Risk Assessment Assumptions


• All those assumptions!

– Dermal uptake models, transfer efficiency, skin pH, non-

depleting source, other assumptions

– Based on different exposure scenarios (children in

contaminated house)

Problems




“Acceptable” Surface Limits (ASL)

• Pharmaceutical Industry Approach

• Based on occupational “Acceptable Daily Intake”

– Similar to RfD

• OADI = (NOAEL * Body Weight)/(Uncertainty Factor*Absorption Factor)

• ASL (mg/cm2) = OADI/Surface Area *Absorption Factor

• “Semi-Quantitative” approach


• SEMI S12 - Environmental, Health and Safety Guideline for Manufacturing Equipment Decontamination:

• Health-Based Clean-up Level (oral) =(RfDXBW)/(SAoxMFxCExAFoXEF)

• Health-Based Clean-up Level (dermal) =(RfDxBWxED)/(SAdxCExAFdxEF)

– Calculate both values, choose the lowest

• Similar approach used by OEHHA to update meth clearance level to 1.5 µg/100cm2

– A 15x increase

Other Risk-Based Approaches:




How Clean is Clean:

What if it is Waste?

Hazardous Waste Evaluation• “Total” amount of contaminant

• Steel plate (36”x36”x1”) contaminated with Cadmium – Wipe test results = 100 µg/100cm2

– Cadmium TTLC = 100 mg/kg (equivalent to 1/10,000)

• 1” (25 mm) plate weighs 196 kg/m2

– 196 kg/10000 = 19.6 g

– (So 19.6 g Cd would exceed TTLC)

• 1 m2 = 10,000 cm2– 10,000 cm2 /100 cm2/wipe = 100 wipes

– 100 wipes x 100 µg/wipe = 10,000 µg = 10 mg = 0.01 g

• 0.01g Cd < 19.6g Cd– Not Hazardous Waste based on “total” levels

– Can also evaluate for TCLP




Hazardous Waste Evaluation• “Extractable” Contaminant

– TCLP = 1 mg/L (D006)

– 1 part “waste” extracted in 20 parts acid (by weight)

– Assume 100% extraction

• Assume 1 ft2

– 196 kg/m2 = 7.3 kg/ft2

– 7.3 kg* 1L/kg*20 = 147L acid

• Contaminant on 1 ft2

– 900 cm2/ft2 / 100 cm2/wipe = 9 wipes

– 9 wipes x 100 µg/wipe = 900 µg = 0.9 mg

– 0.9 mg/147L = 0.006 mg/L

– Not Hazardous waste based on Cd TCLP


How Clean is Clean:

More Problems!



Sampling Strategy

• Where to sample,

• How to Sample

• Sampling Strategy & Number of samples

– Random?

– Authoritative or targeted sampling??

• Level of confidence needed or scrutiny

• Degree of hazard


Sampling Strategy Problems!!!• Lack of Clear Guidance on Sampling Strategy

• Back to Basics (lets define our terms):– “Sample” - portion of population, used to make inferences

about the population• Validity of inferences assumes samples represent population

• Accuracy & Precision require adequate # of “representative samples”

– “Population” must have well-defined physical and/or temporal boundaries.

• Does the level of indoor surface contamination constitute a “population”?


Or



EPA SW 846 Chapter 9• Simple random sampling adequate for randomly

heterogeneous populations– a suitable # of samples is randomly selected from the

population.

• Stratified random sampling used for non-random heterogeneity– the population stratified to account for non-randomness

• Also– Systematic Grid Sampling

– Random Sampling w/in Grid

• Which works for us?


Factors to Consider

• Design and layout of area to be

sampled• (Localized spill or systematic contamination)

• “Random” or “authoritative sampling

• Statistical evaluation (if appropriate)

– Number of samples to be taken




Sampling Locations to Consider• Work areas where contaminant is handled

• Exterior of work area of containment equipment

• Floor of work area

• Access to work area

• Surfaces (Counter tops) and equipment in work area

• Equipment

• “Clean” area – e.g adjacent office or break rooms

• Storage Areas


Sampling Strategy Influences Results!

• Size of the sampling area (100 cm2, 1 ft2)

• Location of the sampling (where they are taken)

• Number of samples (1-4)




Effect of Sample Area

• Small Sample areas

may “miss”

contamination

• Larger samples areas

(or higher #)

increase likelihood

of finding

contamination


Area to evaluate – approx. 1 m2

Location of

contamination

HUD and other Guidance• HUD Guidelines for the Evaluation and Control of Lead-

Based Paint (2012 Edition) Chapter 15– For common areas, one floor sample for every 2,000 ft2 and one floor

sample outside

• San Diego DEH Site Assessment and Mitigation (SAM) Manual, Chapter 5, Site Investigation– References SW 846 - Stockpiles assumed to have non-homogeneous

distribution

– Stockpiles <10 yd3 - minimum 2 random samples

– 10 -20 yd3 - min 3 random samples

– 20-100 yd3 - min 4 random samples

– 100-500 yd3 – min 1 random sample per each 25 yd3

• Are these applicable?BASS 2019 - Evaluating Surface Contamination 44



Industrial Hygiene Strategy• NIOSH Occupational Exposure Sampling Strategy Manual (Leidel &

Busch, 1977)– “Maximum Risk Worker” in homogenous population

– # of samples (n) to collect to be confident that at least 1 sample in xx% are included = log a/log (1 – t)

– τ = fraction %, α = CI (0.1, 0.05


Industrial Hygiene Approach

• Do we have a population?

• Is our “population” different areas?

• How big or small?

– Does that matter?

• Is there anything wrong with

“professional judgment” to identify

potentially contaminated areas?




And All This Assumes Good Data!

• Wipe sampling variability

– Standard Procedures

• NIOSH Method 9100, Lead in Surface Wipe

Samples,

• Chapter 2, Appendix II:2-1 of the OSHA Technical

Manual and

• Residential Sampling for Lead: Protocols for Dust

and Soil Sampling, EPA 747-R-95-001 (March 1995).

• Variability poorly characterized

– Inter-personal Differences

– Differences between surfaces


Other Sampling Issues

• Solubility of contaminant in extraction solvent

• Type of wipe sampling material

• Recovery efficiency of contaminant from surface

material and sampling materials

• Recovery efficiency of drug from sampling material

• Analytical capabiliites (especially for exotic organics

• So What to Do?!?




General Process for Addressing Surface

Contamination• Identify (potential) Contaminants

• Measure (or estimate) extent/degree of contamination

• Evaluate levels with respect to applicable standards!

• Prepare plan to address any concerns

• Implement Plan

• Evaluate performance

• Prepare Report documenting (successful) efforts!– ANSI Z9.11 is useful guidance

– Also 40 CFR 261.35 Decontamination of F032 (chlorophenolic) wastes

• This is a “SAFETY” issue more than an environmental issue!– (but which regulators are usually involved?)


• Understand the process – go through all the steps

• Know what you’re getting into!

• Choose appropriate limit

– (don’t start till you know where you are going)

• Prepare a plan (before you start work), and

communicate it to stakeholders

• Follow the plan!

Conclusion




References• WTC Indoor Environment Assessment: Selecting Contaminants of

Potential Concern and Setting Health-Based Benchmarks (5/1/2003)– http://www.epa.gov/wtc/reports/contaminants_of_concern_benchmark_study.pdf

• BNL IH75190 Surface Wipe Sampling Procedures, 05/10/11– http://www.bnl.gov/esh/shsd/sop/pdf/ih_sops/ih75190.pdfHUD Guidelines

• Guidelines for the Evaluation and Control of Lead-Based Paint Hazards in Housing (2012 Edition)– http://portal.hud.gov/hudportal/HUD?src=/program_offices/healthy_homes/lbp/hudguidelines

• EPA Risk Assessment Guidance and Tools– http://www.epa.gov/risk_assessment/guidance.htm

• SEMI S12-0211: Environmental, Health and Safety Guideline for Manufacturing Equipment Decontamination– http://ams.semi.org/ebusiness/standards/SEMIStandardDetail.aspx?ProductID=211&DownloadI

D=1883


For More Information

James Kapin, MPH, CIH

Manager of EM Services

ACTenviro

www.actenviro.com

[email protected]

619-990-5955


http://www.epa.gov/wtc/reports/contaminants_of_concern_benchmark_study.pdf

http://www.actenviro.com/

mailto:[email protected]

Documents

BASS 2019 - Evaluating Surface Contamination - James Kapin.pdf · BASS 2019 - Evaluating Surface Contamination James Kapin, MPH, CIH [email protected] 619-990-5955 2 XYZ BioNanoPharmaX