Statistical Evaluation of the UTAB Database for Use in Terrestrial Nontarget Organism Probabilistic Risk Assessments

摘要

This paper provides a statistical analysis of the UTAB database (uptake/ accumulation, translocation, adhesion, and biotransformation). This database contains extensive data on organic chemicals and heavy metals in vascular plants. Data from the UTAB database are currently used by the U.S. Environmental Protection Agency (EPA) and pesticide registrants for conducting deterministic risk assessments of pesticide residues in the food chain of wildlife for pesticide registration. The primary purpose for this detailed analysis of UTAB data was to develop models for the distribution of pesticide residues in plant feed items so that these residue distributions can be used in probabilistic risk assessments for wildlife. Relevant data were grouped into the four feed item categories used by EPA for wildlife risk assessment. The data were analyzed statistically and percentiles were calculated. Results were compared to the currently used deterministic maximum and typical residue predictions of the U.S. EPA residue nomogram. More importantly, log normal and exponential distribution models were developed from the analysis, allowing simulation of typical and extreme dietary exposure scenarios in a probabilistic manner. These models can be used in Monte Carlo simulations to generate joint probability functions for a more probabilistic approach to wildlife risk assessment.