Title
Cross-validation and refinement of the Stoffenmanager as a first tier exposure assessment tool for REACH
Author
Schinkel, J.
Fransman, W.
Heussen, H.
Kromhout, H.
Marquart, H.
Tielemans, E.
TNO Kwaliteit van Leven
Publication year
2010
Abstract
Objectives: For regulatory risk assessment under REACH a tiered approach is proposed in which the first tier models should provide a conservative exposure estimate that can discriminate between scenarios which are of concern and those which are not. The Stoffenmanager is mentioned as a first tier approach in the REACH guidance. In an attempt to investigate the validity of the Stoffenmanager algorithms, a cross-validation study was performed. Methods: Exposure estimates using the Stoffenmanager algorithms were compared with exposure measurement results (n=254). Correlations between observed and predicted exposures, bias and precision were calculated. Stratified analyses were performed for the scenarios "handling of powders and granules" (n=82), "handling solids resulting in comminuting" (n=60), "handling of low-volatile liquids" (n=40) and "handling of volatile liquids" (n=72). Results: The relative bias of the four algorithms ranged between -9% and -77% with a precision of approximately 1.7. The 90th percentile estimate of one out of four algorithms was not conservative enough. Based on these statistics and analyses of residual plots the underlying algorithm was adapted. Subsequently, the calibration and the cross-validation dataset were merged into one dataset (n=952) used for calibrating the adapted Stoffenmanager algorithms. This new calibration resulted in new exposure algorithms for the four scenarios. Conclusions: The Stoffenmanager is capable of discriminating among exposure levels mainly between scenarios in different companies. The 90th percentile estimates of the Stoffenmanager are verified to be sufficiently conservative. Therefore, the Stoffenmanager could be a useful tier 1 exposure assessment tool for REACH.
Subject
Research
volatile agent
accuracy
algorithm
article
calibration
controlled study
drug granule
occupational exposure
powder
prediction
priority journal
risk assessment
stoffenmanager algorithm
validation study
work environment
workplace
Algorithms
Bias (Epidemiology)
Environmental Monitoring
Hazardous Substances
Humans
Inhalation Exposure
Models, Statistical
Occupational Exposure
Reproducibility of Results
Risk Assessment
To reference this document use:
http://resolver.tudelft.nl/uuid:8b94f11b-e69f-49f1-a3a9-5902713cb072
DOI
https://doi.org/10.1136/oem.2008.045500
TNO identifier
347468
ISSN
1351-0711
Source
Occupational and Environmental Medicine, 67 (2), 125-132
Document type
article