Uncertainty analysis of regional mercury exposure.
A modeling system has been developed to simulate regional environmental exposure to mercury due to atmospheric deposition of mercury to watersheds.
The atmospheric fate and transport of mercury is simulated using a comprehensive three-dimensional Eulerian model, the Trace Element Atmospheric Model (TEAM).
The aquatic chemistry and bioaccumulation of mercury in fish are simulated using a model of mercury cycling in a lake/watershed system, the Regional Mercury Cycling Model (R-MCM).
Fish consumption was derived from a review of available surveys.
Previous work focused on an assessment of the environmental and inter-individual variability in key input data (Seigneur et al., 1997a).
We address here the uncertainties associated with critical model input variables (e.g., atmospheric deposition velocities, precipitation rate, limnological characteristics).
A probabilistic assessment is conducted to propagate the uncertainties in the input data through the modeling system and develop a probability distribution of the human mercury dose that reflects these uncertainties.
The standard deviation of the distribution of the calculated human dose is about 50% of the mean value.
For the example considered here (i.e., Park Lake in Michigan, U.S.A.), 80% of the uncertainty in the human dose was due to uncertainties in the speciation of mercury air emissions, pH and temperature of the lake, burial velocity of the sediments, and rate of fish consumption.
Mots-clés Pascal : Métal lourd, Mercure, Pollution air, Retombée atmosphérique, Pollution eau, Eau surface, Bassin versant, Devenir polluant, Phénomène transport, Hydrochimie, Accumulation biologique, Pisces, Vertebrata, Chaîne alimentaire, Dose absorbée, Modélisation, Modèle mathématique, Modèle 3 dimensions, Equation Euler, Incertitude, Analyse sensibilité, Loi probabilité
Mots-clés Pascal anglais : Heavy metal, Mercury, Air pollution, Atmospheric fallout, Water pollution, Surface water, Watershed, Pollutant behavior, Transport process, Hydrochemistry, Biological accumulation, Pisces, Vertebrata, Trophic chain, Absorbed dose, Modeling, Mathematical model, Three dimensional model, Euler equation, Uncertainty, Sensitivity analysis, Probability distribution
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 99-0332482
Code Inist : 001D16E. Création : 16/11/1999.