Weekly Pesticide Measurements in 100 Midwestern Streams (2013)

227 pesticide compounds were measured in weekly water samples from 100 wadeable streams across eleven Midwestern U.S. states during a 14-week period in 2013. The U.S. Geological Survey collected twelve samples per site, analyzing them for aquatic toxicity using the Pesticide Toxicity Index and EPA benchmarks. This dataset supports research on complex pesticide mixtures and their effects on stream ecosystems.

Use Cases

• Analyze pesticide concentration data across 100 stream sites to identify spatial patterns along an agricultural land-use gradient.
• Evaluate potential aquatic toxicity by applying the Pesticide Toxicity Index to measured pesticide compound levels.
• Investigate the effects of the insecticide imidacloprid using invertebrate metrics and concentration data from the included mesocosm experiment.
• Correlate agricultural pesticide use data with measured pesticide concentrations in environmental water samples.

Strengths

• Data covers 100 distinct stream sites, providing a broad spatial sample across eleven states.
• Analysis targeted 227 specific pesticide compounds, offering a detailed chemical profile.
• Sampling involved twelve weekly collections per site over a 14-week period, capturing temporal variation.
• Study design includes 12 urban indicator sites and 88 sites along an agricultural gradient for comparative analysis.

Limitations

• Data is from a single year (2013), limiting analysis of long-term trends or recent conditions.
• Focus is exclusively on the Midwestern U.S., so findings may not generalize to other geographic regions.
• Sample data and specific column structure are unavailable, complicating initial data exploration.

Provenance

Source

U.S. Geological Survey (USGS) National Water Quality Assessment (NAWQA) Project.

Collection Method

Weekly water samples were collected, filtered, and analyzed via liquid chromatography with tandem mass-spectrometry (227 compounds) and ELISA (glyphosate).

Time Range

May-August 2013.

Freshness

Data was last updated in February 2026, but the underlying study period is 2013.

Geography

100 wadeable streams across eleven states in the Midwestern United States.