Post on 14-Aug-2020
Modelleren én metenModelleren én meten
Wouter Fransman, Erik Tielemans
Programma workshopProgramma workshop
1) Algemene introductie ) g-Erik-
2) ART voorbeelden -Wouter-
3) Toekomstige ontwikkelingen / rol NVvA (?)3) Toekomstige ontwikkelingen / rol NVvA (?) -Erik-
NVvA Symposium, 24 maart 2010the ART of exposure assessment2
Nieuwe ontwikkelingenNieuwe ontwikkelingen
• REACH geeft modelontwikkeling een nieuwe impulsg g pTier 1: Ecetoc TRA, BAuA tool, StoffenmanagerTier 2: Advanced REACH Tool
• Nieuwe meetstrategie in ontwikkelingBOHS – NVvA initiatief
NVvA Symposium, 24 maart 2010the ART of exposure assessment3
Making full use of informationMaking full use of information
?ai
nty
+ BDA
Unc
erta + BDA
Model Data Updated estimateModel Data Updated estimate
NVvA Symposium, 24 maart 2010the ART of exposure assessment4
ART approachART approach
Exposure database, with contextualwith contextual
information
Model Similarity module to select data for risk
assessment
Bayesian process to combine data
and model outputand model output
Exposure estimatesExposure estimates for risk assessment
NVvA Symposium, 24 maart 2010the ART of exposure assessment5
Mechanistic model ART
9 Modifying Factors (MF):
- Intrinsic emission potential (E)- Activity emission potential (H)Equations:- Local controls (LC)- Separation (Sep) - Segregation (Seg)RPECCC ffnft ⋅+= )(
Equations:
g g ( g)- Surface contamination (Su)- Dilution (D)- Personal behavior (P)
nfnfnfnfnfnfnf DSuPLCHEC ⋅+⋅⋅⋅= )(
ffffffffffffffff SepDSuSegLCHEC ⋅⋅+⋅⋅⋅= )( Personal behavior (P)- RPE
ffffffffffffffff
NVvA Symposium, 24 maart 2010the ART of exposure assessment6
Hierarchical structuringHierarchical structuring
Modifying Factor 1 Modifying Factor 2 Modifying Factor 3
Underlying determinants
Underlying determinants
Underlying determinants
NVvA Symposium, 24 maart 2010the ART of exposure assessment7
Substance Emission Potential (dustiness)Substance Emission Potential (dustiness)
Category Relative g yweight
Firm granule 0.01
Granule 0.03
Coarse dust 0.1
Fine dust 0.3
E t l 1 0Extremely fine dust
1.0
NVvA Symposium, 24 maart 2010the ART of exposure assessment8
Activity Emission PotentialActivity Emission Potential
Powders
Liquids
Solid objects
Hot / molten metal
NVvA Symposium, 24 maart 2010the ART of exposure assessment9
NVvA Symposium, 24 maart 2010the ART of exposure assessment10
local controlslocal controls
• No localized controls
• Suppression techniques• Wetting at the point of release• Knockdown suppression (post generation suppression)
• Containment (non-extracted)
• Local ventilation systems Efficacy = 0.5Local ventilation systems• Receiving hoods
• Canopy hoods (hot processes)• Other receiving hoods
• Capturing hoodsEfficacy = 0.0001
• Fixed• Movable• On-tool (integrated) extraction
• Enclosing hoods• Glove boxGlove box• Fume cupboard• LEV systems with partial enclosure (no front cover)
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DispersionDispersionQFF Q
NFNF εTIndoor
Outdoor
Spray booth
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Calibration with measurementsCalibration with measurements
• Using multiple sourcesg pAlso including measurements in the low range
• Only good quality data: N~2,500
• Quantification in units (mg/m3)
• Provides model uncertainty
S t di ti f• Separate predictions for:DustVapourMistMistFumes PhD Jody Schinkel
NVvA Symposium, 24 maart 2010the ART of exposure assessment13
Bayesian modelBayesian model
• Bayesian techniques allow for different y qtypes of information to be integrated in a theoretically rigorous way via probability theorytheory
• Bayes approach takes account of the relative strength of the different information sources
• Bayesian module is integrated in ART to update model estimate with user’s own data
NVvA Symposium, 24 maart 2010the ART of exposure assessment14
Hierarchical exposure modelHierarchical exposure model
• Between company variabilityp y y
• Between worker variabilityComp-1 Comp-2 Comp-n
• Within worker variabilityComp-1 Comp-2 Comp-n
Worker-1 Worker-2 Worker-n
Day-1 Day-2 Day-n
NVvA Symposium, 24 maart 2010the ART of exposure assessment15
Weight of EvidenceWeight of Evidence
• Large sample size
• Multiple companies
>> Small sample sizes
>> Single company• Multiple companies
• Uniform measurement series
>> Single company
>> Heterogeneous measurement series
• Analogous data >> Partially analogous data
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ART - outputART output
• Explicit treatment of variability and uncertaintyPercentile of distributionUncertainty of estimateUncertainty of estimate
Variability
Uncertainty90th , 75th , 50th percentile
y
Inter quartile 80 % 90 % 95 % CINVvA Symposium, 24 maart 2010the ART of exposure assessment17
Inter-quartile, 80 %, 90 %, 95 % CI
Contributions from…Contributions from…
• Health & Safety Executive
• Dutch Ministry
• CEFIC LRI
• Afsset
• Shell
Eurometaux• Eurometaux
• BOHS
• GlaxoSmithKline
NVvA Symposium, 24 maart 2010the ART of exposure assessment18
Acknowledgement – external expertsAcknowledgement external experts
• S. Bailey (GSK, UK)• D Brouwer (TNO The Netherlands)D. Brouwer (TNO, The Netherlands)• M. Byrne (University of Galway, Ireland)• D. Dahmann (Bochum University, Germany)• J. Dobbie (BP, UK)• D. Gazzie (Industrial Health Control, UK)• A. Gillies (Gillies Associates Ltd, UK)( , )• E. Joseph (GSK, UK)• I. Kellie (OHS Scotland Ltd, UK)• D. Mark (HSL, UK)• P. McDonnell (University of Galway, Ireland)• M. Newell (Bayer Crop Sciences, UK)• M. Nicas (University of California, USA)• D. O’Malley (Genesis Environmental Ltd, UK)• M. Piney (HSL, UK)• A. Robertson (IOM, UK)• J. Saunders (HSL, UK)
M Smith (Ba er Crop Sciences UK)• M. Smith (Bayer Crop Sciences, UK)• H. Tinnerberg (Lund University, Sweden)• H. Westberg (Örebro University Hospital, Sweden)• A. Wolley (Wolley Associates, UK)• J. Wren (GSK, UK)• D Iddon (Lilly UK)• D. Iddon (Lilly, UK)• D. Noy (Dow chemicals, NL)• J. Urbanus (Shell, NL)• R. Battersby (EBRC consulting, Germany)
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d d h lwww.advancedreachtool.com
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