Comparison of the predictions of two models with dose measurements in a case of children exposed to the emissions of a lead smelter

Comparison of the predictions of two models with dose measurements in a case of children exposed to the emissions of a lead smelter

TitleComparison of the predictions of two models with dose measurements in a case of children exposed to the emissions of a lead smelter
Publication TypeJournal Article
Year of Publication2009
AuthorsRoseline Bonnard, Thomas E McKone
JournalJournal of Human and Environmental Risk Assessment
Volume15
Issue6
Pagination1203-1226
ISSN1080-7039
KeywordsEnvironmental Chemistry, Exposure and Risk Group, exposure and health effects, exposure assessment, ieubk, indoor environment department, lead, multimedia models, probabilistic risk assessment
Abstract

The predictions of two source-to-dose models are systematically evaluated with observed data collected in a village polluted by a currently operating secondary lead smelter. Both models were built up from several sub-models linked together and run using Monte-Carlo simulation, to calculate the distribution children's blood lead levels attributable to the emissions from the facility. The first model system is composed of the CalTOX model linked to a recoded version of the IEUBK model. This system provides the distribution of the media-specific lead concentrations (air, soil, fruit, vegetables and blood) in the whole area investigated. The second model consists of a statistical model to estimate the lead deposition on the ground, a modified version of the model HHRAP and the same recoded version of the IEUBK model. This system provides an estimate of the concentration of exposure of specific individuals living in the study area. The predictions of the first model system were improvedin terms of accuracy and precision by performing a sensitivity analysis and using field data to correct the default value provided for the leaf wet density. However, in this case study, the first model system tends to overestimate the exposure due to exposed vegetables. The second model was tested for nine children with contrasting exposure conditions. It managed to capture the blood levels for eight of them. In the last case, the exposure of the child by pathways not considered in the model may explain the failure of the model. The interest of this integrated model is to provide outputs with lower variance than the first model system, but at the moment further tests are necessary to conclude about its accuracy.

DOI10.1080/10807030903304849
LBNL Report Number

LBNL-2397E