EXPERIENCING A PROBABILISTIC APPROACH TO CLARIFY AND DISCLOSE UNCERTAINTIES WHEN SETTING OCCUPATIONAL EXPOSURE LIMITS

Vernez, D; Fraize-Frontier, S; Vincent, R; Binet, S; Rousselle, C

HERO ID

10757509

Reference Type

Journal Article

Year

2018

HERO ID 10757509
In Press No
Year 2018
Title EXPERIENCING A PROBABILISTIC APPROACH TO CLARIFY AND DISCLOSE UNCERTAINTIES WHEN SETTING OCCUPATIONAL EXPOSURE LIMITS
Authors Vernez, D; Fraize-Frontier, S; Vincent, R; Binet, S; Rousselle, C
Journal International Journal of Occupational Medicine and Environmental Health
Volume 31
Issue 4
Page Numbers 475-489
Abstract OBJECTIVES: Assessment factors (AFs) are commonly used for deriving reference concentrations for chemicals. These factors take into account variabilities as well as uncertainties in the dataset, such as inter-species and intra-species variabilities or exposure duration extrapolation or extrapolation from the lowest-observed-adverse-effect level (LOAEL) to the noobserved- adverse-effect level (NOAEL). In a deterministic approach, the value of an AF is the result of a debate among experts and, often a conservative value is used as a default choice. A probabilistic framework to better take into account uncertainties and/or variability when setting occupational exposure limits (OELs) is presented and discussed in this paper. MATERIAL AND METHODS: Each AF is considered as a random variable with a probabilistic distribution. A short literature was conducted before setting default distributions ranges and shapes for each AF commonly used. A random sampling, using Monte Carlo techniques, is then used for propagating the identified uncertainties and computing the final OEL distribution. RESULTS: Starting from the broad default distributions obtained, experts narrow it to its most likely range, according to the scientific knowledge available for a specific chemical. Introducing distribution rather than single deterministic values allows disclosing and clarifying variability and/or uncertainties inherent to the OEL construction process. CONCLUSIONS: This probabilistic approach yields quantitative insight into both the possible range and the relative likelihood of values for model outputs. It thereby provides a better support in decision-making and improves transparency. Int J Occup Med Environ Health 2018;31(4):475-489.
Doi 10.13075/ijomeh.1896.01184
Wosid WOS:000441070500006
Url https://www.ncbi.nlm.nih.gov/pubmed/29546881
Is Certified Translation No
Dupe Override No
Is Public Yes
Keyword Animals; Models, Statistical; No-Observed-Adverse-Effect Level; Occupational Exposure/standards; Risk Assessment/statistics & numerical data; Toxicology/statistics & numerical data; Uncertainty; assessment factors; chemical toxicity; occupational exposure limits; probabilistic methods; risk management; uncertainty distributions