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Nitrapyrin in streams: The first study documenting off-field transport of a nitrogen stabilizer compound

Emily E. Woodward·Michelle Hladik·Dana W. Kolpin
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Abstract

Nitrapyrin is a bactericide that is co-applied with fertilizer to prevent nitrification and enhance corn yields. While there have been studies of the environmental fate of nitrapyrin, there is no documentation of its off-field transport to streams. In 2016, 59 water samples from 11 streams across Iowa were analyzed for nitrapyrin and its degradate, 6-chloropicolinic acid (6-CPA), along with three widely used herbicides, acetochlor, atrazine, and metolachlor. Nitrapyrin was detected in seven streams (39% of water samples) with concentrations ranging from 12 to 240 ng/L; 6-CPA was never detected. The herbicides were ubiquitously detected (100% of samples, 28–16000 ng/L). Higher nitrapyrin concentrations in streams were associated with rainfall events following spring fertilizer applications. Nitrapyrin persisted in streams for up to 5 weeks. These results highlight the need for more research focused on the environmental fate and transport of nitrapyrin and the potential toxicity this compound could have on nontarget organisms.

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Emily E. Woodward, Michelle Hladik, Dana W. Kolpin. 2016-10-14. Nitrapyrin in streams: The first study documenting off-field transport of a nitrogen stabilizer compound. https://doi.org/10.1021/acs.estlett.6b00348

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