Till Bachmann, IER Stuttgart NewExt WP4 "Multimedia impact pathways" Presentation by Till...

Till Bachmann, IER Stuttgart

NewExtWP4

"Multimedia impact pathways"

Presentation by Till M. Bachmann Villigen, 26 May 2003

Till Bachmann, IER Stuttgart

Introduction

• Objectives of WP:(according to description of work)– Site-dependent assessment of concentration levels

in soil and water compartments– Exposure assessment with respect to ingestion by

humans considering food chains– Total exposure assessment (ingestion + inhalation)– 'As far as possible' quantifying impacts and

damages

Introduction

Till Bachmann, IER Stuttgart

WATSON-Europe

• Acronym for: – Integrated WATer and SOil environmental fate,

exposure and impact assessment model of Noxious substances for Europe

• Box model for water and soil coupled to regional air quality model WTM (Windrose Trajectory Model) of EcoSense

EcoSense multimedia

Till Bachmann, IER Stuttgart

Atmosphericemissions

Background (natural+ anthropogenic)

Direct emissionsto water and soil

Sources ofsubstances

Regional scaleatmospheric models

Air model

Soils ofdifferent use

Soil &waterModel Sediment

freshGroundwater

Waterfresh

Watermarine

Sedimentmarine

Drinkingwater

Aquaticorganisms

Exposuremodel

Farmanimals

Human beingsinhalation exposure not shown

Plants

En

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on

men

tal f

ate

mo

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EcoSense multimedia

Till Bachmann, IER Stuttgart

Top soils of:– Pastures– Arable land– Non-vegetated areas

(e.g. rocks, open cast mining)– Semi-natural ecosystems

Other compartments:– Freshwater bodies– Sediment

– Built-up areas– Glaciers

Spatial characteristics• Environmental media distinguished taking differences

in permeability, soil erosion and human (in)direct exposure into account

• These are:

about 11500 different compartments in 3400 base regions

EcoSense multimedia

Till Bachmann, IER Stuttgart

Temporal characteristics• Climatological annual average data for hydrology• Temporal resolution:

– Steady-state: for sustainability questions („Which concentration will occur in media and food if the current emissions are kept the same forever?“)

– Quasi dynamic: temporal concentration development in different media and food (‚quasi‘: only a substance‘s concentrations vary)

• Pulse emission: emission stops after a given time

– „Time to steady-state“: assessing when a certain percentage of the steady state solution will be reached (very persistent substances like heavy metals will only reach a steady-state after several hundred or even thousand and more years)

EcoSense multimedia

Till Bachmann, IER Stuttgart

Scenario• Case study: 1000 kg Pb/a emitted in Flanders

Scenario calculations

• Reference: European emissions in 1990 (UBA/TNO 1998)

• Exposure via inhalation and ingestion

Till Bachmann, IER Stuttgart

Concentration increment

Till Bachmann, IER Stuttgart

Collective dose of Pb - resultsScenario calculations

• Summed over national average exposures• Ingestion exposure only via milk, beef, cereals and potatoes

UWM (power plants)

WATSON

Inhalation 2.84 10-6 1.07 10-5

Ingestion 1.60 10-4 1.17 10-3

Total 1.63 10-4 1.18 10-3

Till Bachmann, IER Stuttgart

Collective dose of Pb - comparisonScenario calculations

• Similar to UWM: – Ingestion dose about two orders of magnitude larger than inhalation

• Dissimilar to UWM: – Dose levels: one order of magnitude higher

– Contribution of different paths (potato and rye!)

– Decreasing intake fraction over time

Till Bachmann, IER Stuttgart

• Two scenarios consideringCd and Pb emissions to Germany and tributary areas:– Atmospheric deposition only

(UBA/TNO 1998)– Plus direct releases into water

(UBA 2000; distribution: i) industry+municipal emissions: per capita, ii) diffuse emissions: area weighted)

• No background• Steady-state concentrations

Sustainability application• Case study for Germany

Scenario calculations

Till Bachmann, IER Stuttgart

• Policy standards (EU directive) with respect to lead:– Arable land: 50-300 mg/kg dry-weight

– Surface waters for drinking water abstraction: 0.05 mg/l

Results – environmental media – PbScenario calculations

concentration range at steady-state

standard exceedances [area %]

Standard min max unit emissions + backgrounda)

arable land 0.79 81.7 [mg/kg d.-wt.]

1.4 %b) 6.0 %c)

surface water

atm. dep. 8.7 10-4 1.2 10-2 [mg/l] 0 % n/a

+ water em. 1.2 10-3 1.7 10-2 [mg/l] 0 % n/a a) background: 17.0 ppm Pb in upper continental crust (Wedepohl, 1995)

time to steady-state for exceedance case: b) 11-24% and c) 11-35% (after 1000 years)

Till Bachmann, IER Stuttgart

• Policy standards with respect to lead:(Commission Regulation (EC) 466/2001 to Directive 2001/22/EC)

– milk consumption (infants): 0.02 mg/kg fresh-weight– meat consumption: 0.1 mg/kg fresh-weight

Results – food consumption – PbScenario calculations

concentration range at steady-state [mg/kg f.-wt.]

standard exceedances

[mass %]

Standard min max

milk 0.0021 0.037 0.9 %

meat 0.0038 0.067 0 %

Till Bachmann, IER Stuttgart

Conclusions

• Air-dispersion based EcoSense is extended to a multi-media exposure assessment tool

• WATSON offers many opportunities to calculate welfare losses via external costs as well as sustainability indicators in terms of long-term environmental media and/or food concentrations

• However, the use of exposure-response functions has not yet been possible due to lack of emission information as well as atmospheric modelling reasons related to PAHs and PCDD/Fs

Conclusion

Till Bachmann, IER Stuttgart

Thank you for

your attention!

Conclusion