Toxicology Commons^™

Technical Memo: Incorporating Mixture Toxicity Into Bayesian Networks To Calculate Risk To Pesticides In The Upper San Francisco Estuary., Eric J. Lawrence, Skyler R. Elmstrom, Emma E. Sharpe, Wayne G. Landis

Institute of Environmental Toxicology & Chemistry Publications

This memo presents the methods we have developed to calculate risk of mixtures of pesticides for the Upper San Francisco Estuary (USFE). We used curve fitting to estimate the exposure-response curves for each individual chemical and then the mixture. For the mixture the models were normalized for specific ECx values. In that way the curve fitting was optimized for effects that are similar to most threshold values. A Bayesian network was then built that incorporated four different pesticides and a specific mode of action. The input distributions of the pesticides were measured amounts from each of the six risk regions. …