Human Exposure and Atmospheric Sciences
Consolidated Pesticide Information Dataset (CPI)
Pesticides are chemical substances or biological agents that eliminate pests from crops, homes, and the environment. While they have beneficial uses, they may also pose potential risks to humans and the environment. (Read more about pesticides.)
Scientists routinely conduct exposure, toxicity and degradation research on small groups of related pesticides. Some pesticides are mixtures of several chemicals or even different forms of the same chemical. Some chemicals may be chiral or, in other words, have different mirror images. Your hands are a common example of chirality. They are mirror images of each other, but if you try to stack your hands, your thumbs will be on opposite sides.
Chiral compounds that have two forms that are mirror images of each other are known as enantiomers. Enantiomers generally behave in similar ways, but they can degrade differently in the environment. Research shows that the less toxic enantiomer sometimes degrades faster, thus increasing the toxicity of the remaining mixture. Sometimes the more toxic enantiomer degrades faster in the environment, thus decreasing the toxicity of the remaining mixture. Because of the complexity of pesticide mixtures, they provide special challenges for monitoring environmental concentrations and for predicting exposures, effects and risks.
EPA scientists have developed the Consolidated Pesticide Information Dataset (CPI) — a spreadsheet dataset compiled from multiple sources that contains basic information for approximately 1,700 pesticides. The dataset contains a total of twenty fields, including chemical names, identification numbers, structures, and pesticide use class - such as insecticide, herbicide, and fungicide.
Using a combination of computer modeling and expert judgement, each structure was evaluated to determine if it was chiral or not. The initial goal of the dataset was to have a comprehensive list of chiral pesticides, but the dataset also consolidates information scattered widely through the Internet, including published and unpublished scientific literature.
Results and Impact
The Consolidated Pesticide Information Dataset (CPI) provides researchers with pesticide information that can be sorted and searched in the familiar format of a spreadsheet. It is a one-stop shop and starting place for basic information, including names, ID numbers, structures, and pesticide use class regarding a large number of pesticides.
This dataset is the only resource known that evaluates chirality explicitly. Of the 1,693 pesticides in this dataset, 482 (28 percent) are chiral. With CPI, researchers can quickly develop a list of insecticides, chiral insecticides, or chiral insecticides that have analytical methods available. Modelers can use the pesticide structures presented to determine if a reaction might happen, if a pesticide will degrade under certain conditions and how it might be transported in the environment or to humans. The CPI dataset will serve as a valuable tool for those interested in pesticide mixtures, green or sustainable pesticides, development of methods and models, and other areas of pesticide research.
Ulrich, E. M.; Morrison, C. N.; Goldsmith, M. R.; Foreman, W. T., Chiral Pesticides: Identification, description, and environmental implication. Reviews of Environmental Contamination and Toxicology 2012, 217, 1-74.
Elin M. Ulrich, PhD