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Federal Institute for Risk Assessment 1
Exposure Data Tools - Current Situation in Europe
Gerhard Heinemeyer
Federal Institute for Risk Assessment
Berlin, Germany2003 ISEA Annual Meeting, Stresa Italy
Federal Institute for Risk Assessment 3
Exp
osu
re
Exposure Factors
Source
Distribution
Release
Deposition
Disappearance
Behaviour
Anthropometrics
Substance
People
Steps in Exposure evaluationScenario
Model Model variables
Descriptions/Characterizations
transformation ofScenario to formula
Data to feed the model
Measurements
Federal Institute for Risk Assessment 4
Claims for Exposure Assessments
Scientific state Evaluation of scenarios, models & exp.
factors? do they and the tools resemble reality? New developments?
Regulatory requirements Agreement upon certain approaches
(incl. Models and data to be taken)
Federal Institute for Risk Assessment 5
I.Scenario descriptions
Federal Institute for Risk Assessment 6
Scenario Descriptions (first step of exposure analysis)
Can be characterized from use instructions Use of categories of use is recommended
(e.g. use of textile as carpet, cloth, furniture) Models can be defined according to
scenarios The exposure factors needed can clearly be
described Harmonization is needed
Federal Institute for Risk Assessment 7
Where can scenario descriptions be found?
EU Technical Guidance Document EPA Exposure factors handbook Food consumption surveys (image scenarios for food
uptake) ETAD reports (Textile emissions) RIVM monographs (paints, toys, biocides) Biocide TGD-draft Literature other publications (example Germany)
Federal Institute for Risk Assessment 8
II.Model evaluations
Federal Institute for Risk Assessment 9
Needs for Consumer Exposure Estimation
Source: Amounts of substances in products, reIeases, uses
Disposition of substance:Identification of release, distribution, ad- and desorption, disappearance
Contact:Behaviour of exposed person,contact times, frequencies, durations
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Models A number of models have been developed
based on published literature OECD has prepared an inventory of models A limited number of tools are regularly used
for exposure evaluation e.g.: EU: EUSES, CONSEXPO, EASE US: SCIES; CEM, MCCEM, THERdBASE
Validation remains a problem
Federal Institute for Risk Assessment 11
Comparison of models
Comparative evaluation of models do not exist Which model for which exposure?
Different concepts for the same problem Computer tools as „black boxes“ Recalculation of models with other tools is
practically not possible, complete algorithms have not been published
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III.Source Data
Federal Institute for Risk Assessment 13
Needs for Consumer Exposure Estimation
Source data Weight fraction (amount) of substance in the
product Releases Amount of residual monomers Use data
Frequencies Durations
Federal Institute for Risk Assessment 14
Datapools for sources of exposure
Product information Why is product information important? The extent of exposure is direct proportional to the amount
of substance in the product.
Frequencies and durations of use can modulate the emissions of the substances from the products
kAE mountxp *
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Datapools for sources of exposure
Information about preparations
Product registers
Switzerland, the nordic countries, Italy, Germany
Poison Information Centres have product information
Safety Data Sheets, Information brochures from industry
Literature
Rules for gathering data are not harmonised different regulations
no common formats
Federal Institute for Risk Assessment 16
Datapools for sources of exposureInformation about articles Furniture, clothings, carpets, buildings, cars, toys etc. The extent of exposure is direct proportional to the amount of
substance that is released by the product
but Knowledge about substances in articles is limited
(downstream users are not aware on the compositions) Knowledge about release is also very limited Measurements in air or dust sometimes give hints for releases
from articles for certain substances (e.g. Flame retardants, PAH, heavy metals, pesticides)
No common data pool
Federal Institute for Risk Assessment 17
Substances in food
We have national surveillance programs for controlling substances (as contaminants) in food by institutions publishing these data
National food consumption studiesData need to be updatedStudies should be harmonised
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Food Monitoring surveillance programme in Germany
National programme measuring substances in food according to a prefixed schedule
contamination of 282 chemicals 137 different categories of food, focus on
• heavy metals• chlorinated hydrocarbons• pesticides
over a period of 12 years
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IV.Peoples behaviour
and
Anthromopetrics
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Needs for Consumer Exposure Estimation
Antropometric data total population subpopulations
Behaviour data (e.g.)• staying inhouse • staying outside• staying at workplace• certain behaviours of subpopulations (focus on children, e.g. playing with toys, sucking)
Federal Institute for Risk Assessment 21
Behaviour data People do influence their own exposure by
behaviour variations in product uses
• frequencies, durations variations in contacts with chemicals
• time pattern, staying home etc. Age dependent behaviours
• hand to mouth contacts– Children– eating at the workplace– hygiene during preparation of food
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Anthropometric Data
Lots of compilations about body weights, heights, and surfaces exist
Regional differences to be mentioned North to South to West to East Europe Scientific and regulation aspects may
deviate considerably
Federal Institute for Risk Assessment 26
Compilations that provide anthropometric data
EPA exposure monographs incl. Handbooks AIHC exposure factors handbook ECETOC Exposure factors sourcebooks RIVM monographs (national data) Standards zur Expositionsabschätzung (national data) EU Technical Guidance Document Annals of the ICRP (Intern. Comm. On Radiological Protection)
many data have been written out from other secondary sources ...
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What about secondary literature - body weight
Albania 61,07 Bosnia-Herzegovina 61,70 Croatia 61,70 Macedonia 61,07 Malta 61,07 Portugal 61,07 Slovenia 61,07 Italy 73,23 Spain 73,23 Yugoslavia 75,28 Greece 76,13
Source: WHO, cited in ECETOC Technical Report
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Children represent a special group of exposed persons
Physiological differences (children are no little adults)
Development (qualitative changes of toxicity during childhood)
Mouthing behaviour
Quantification is difficult
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Information about children
Scientific literature US-EPA Danish EPA some publications from RIVM workshops hundreds of publications covering children‘s
exposures and dealing with specific questions, but comprehensive collections of high quality information is scarce
Federal Institute for Risk Assessment 30
Data sources for exposure assessments in children
Cohen Hubal et al, Env. Health Persp. 2003 insufficient data on children's exposures and
activities multimedia exposures to environmental
contaminants cannot be assessed default assumptions are taken for exposure
assessments reduction of uncertainty in the assumptions and
exposure estimates is needed
Federal Institute for Risk Assessment 31
V.Quality aspects
Federal Institute for Risk Assessment 33
Very conservative and hypothetical valuesHigh degree of uncertainty
Default
Worst case
50th percentile
Whole distribution
Leve
l of
qual
ity
Sin
g le
poin
t es
timat
esD
ist r
ibu t
i on
bas
ed
99th percentile
50th percentile 99th percentile
High quality data are representative, they characterize the range and variability
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Data quality?
ValidationRepresentativeness
Transparency
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RIVM quality factors9 Not questionable8 good value, discussion possible7 enough space6 useful, improvement needed5 doubtful, can be used as a default4 doubtful, can not be completely
used a default3 bad value, not useful as a default2 useless, but nearer conceivabilities1 useless, no conceivabilities
1
2
4
7
2
3
0
0
0
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Data quality of some exposure factors
Body weight and heightformulations
physiologic datause descriptionsfood consumption
time patternshouse and room characteristics
room ventilationdermal uptake datadust and soil uptake
hand to mouth emission rates
migration of substances in materialetc.
Level
of
quality
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Future aspects (under the aspects of regulation)
Exposure factors and exposure data compilations with the objective for
Standardization Harmonization Completeness Representativeness Ranges Uncertainty and Variability
Compile a network for continous update Data mining (inventory of exposure data)
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The needs we have for exposure assessments
only partly meetthe tools
Lots of data have been evaluated but they are not available unless they are published in a regular wayor otherwise widely available (e.g. per internet)
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Thank you
for attention
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Transparent presentation Criteria for data compilations are transparent and
well understood source, method of analysis
Standardized methodology has been used Original literature, secondary to be avoided The procedure can be repeated easily by other
people than the authors e.g a model can by easily be recalculated (many of the
computer tools for exposure analysis are „black boxes“) overinterpretation of data from literature which does not
meet the intention of the paper
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Representativeness
Data have been evaluated using standard epidemiologic and statistical methodology
The selection of the study population has been performed by a transparent procedure
Confounders have been considered Correlation of compared data is checked
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Validation
The result obtained by modelling will be similar to measurements obtained under comparable conditions (same scenario)
Sensitivity analysis
The influence of variables that have great or low influence in the model that is used is analysed and well described
Federal Institute for Risk Assessment 44
Institutes and Organisations Publishing Data about Exposure in Germany
Superior federal institutions UBA, BfR, BAM etc.
Institutions of Federal states Federal state scientific institutions (e.g. universities) Public foundations Industry and manufacture Private associations and foundations Non governmental organisations Private laboratories