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Pesticide Toxicity Index (PTI) and maximum Toxic Unit (TUmax) scores and information for fish, cladocerans, and benthic invertebrates from water samples collected at National Water Quality Network sites during Water Years 2013-2017

July 9, 2020

During 2013-2017, the U.S. Geological Survey, National Water-Quality Assessment (NAWQA) Project, collected water samples year-round from the National Water Quality Network - Rivers and Streams (NWQN) and reported on 221 pesticides at 72 sites across the US in agricultural, developed, and mixed land use watersheds. Pesticide Toxicity Index (PTI) scores, a screening-level tool that uses an additive, toxic-unit model, were calculated to estimate the potential chronic and acute toxicity to 3 taxonomic groups - fish, cladocerans, and benthic invertebrates. The pesticide that makes the single largest (maximum) contribution to the PTI is called TUmax. This dataset consists of the PTI and TUmax scores, as well as, the TUmax pesticide names, types, and parent/degradate designations for fish, cladocerans, and benthic invertebrates in each sample.

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