A common pesticide coating on corn and soybean seeds has leached into Minnesota waterways, threatening pollinators and aquatic ecosystems, according to a report released this week by the environmental group Natural Resources Defense Council.
Neonicotinoid pesticides, or “neonics,” are a group of insecticides that kill pests like aphids — but can also devastate bee colonies and aquatic insects, leading to a chain of negative effects in the polluted ecosystem.
The NRDC report, written by Pierre Mineau, a research scientist who worked for the Canadian government and teaches at Canada’s Carleton University, found that most Minnesota waterways have some amount of neonic pollution.
Using sampling data from the Minnesota Department of Agriculture, Mineau found that over a 12-year period, 95% of flowing-water sites had at least one neonic chemical, and 87% of the sites showed a mixture of two or more neonic chemicals.
“Where neonics were found, they appeared in most cases at concentrations expected to do biological harm,” Mineau wrote.
Ninety percent of neonic pollution in Minnesota comes from agricultural uses.
The Minnesota Department of Agriculture considers two common neonicotinoids — clothianidin and imidacloprid — “surface water pesticides of concern.” The department encourages the adoption of “best management practices” for those two neonicotinoids, including rotating neonics with other types of insecticides and using the lowest effective amount of the pesticide.
Some U.S. states, and the European Union, have banned or severely limited some of the most common neonics.
Farm groups have opposed attempts to rein in the use of neonics. When the New York state legislature passed a bill banning neonicotinoid-coated seeds last year, the state Farm Bureau called on New York Gov. Kathy Hochul to veto the bill. (She did not.)
“Seeds treated with neonicotinoids were designed to be safer and reduce pesticide use…we believe the end result of this ban will force farms to revert back to spraying greater amounts of older pesticides as well as increasing tillage to combat harmful pests, releasing more carbon in the soil and increasing the likelihood of soil erosion,” New York Farm Bureau President David Fisher said.
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