REGIONAL— Preliminary results of a new study by the Department of Natural Resources, find that deer across Minnesota, including in St. Louis County, are showing the presence of neonicotinoid …
REGIONAL— Preliminary results of a new study by the Department of Natural Resources, find that deer across Minnesota, including in St. Louis County, are showing the presence of neonicotinoid pesticides in their systems.
Neonicotinoids, often referred to as “neonics,” are the most widely used class of insecticides worldwide and are found in more than 500 commercial and domestic products in the U.S. They are present in a wide array of products used for insect control in homes, gardens, yards, and crops, as well as on pets.
The study sampled 800 deer spleens, provided by hunters from around the state, looking for the presence of neonics. The pesticides were found in 61 percent of the samples tested, and some deer permit areas in northern St. Louis County had an even higher detection rate. Deer permit area 176, for example, located south of Hwy. 1 and west of Hwy. 135, had six of seven sample spleens tested come back positive for neonics. While hunters in most other permit areas in St. Louis County sent few samples (most had just one or two samples submitted) positive tests were found in every one, except permit area 130, where a single sample came back negative.
The DNR launched its research project in late 2019, following a study conducted on captive deer in South Dakota that raised concerns about potential adverse effects of neonicotinoid exposure, including reduced fawn survival. Further analysis is required to determine if the levels of exposure seen are high enough to adversely affect deer health. Additional study results related to exposure levels will be available this spring.
“We wanted to know if wild deer in natural settings are being exposed to neonics and if certain habitat types had a higher risk,” said Michelle Carstensen, DNR’s wildlife health program supervisor. “Minnesota is a great place to ask this question, as deer are dispersed across the forest, farmland, prairies, and urban landscapes.”
While these preliminary data focused on deer, Minnesota Department of Health believes there is likely little-to-no human health risk for consuming venison from deer that may have been exposed to neonicotinoids. These early findings suggest concentrations found in the deer spleen samples were far below the U.S. Environmental Protection Agency’s allowable levels for consumption of other foods, like fruit or beef, that may have neonic residue.
The Minnesota DNR is planning additional sampling this fall and is exploring future research options on neonicotinoids in wildlife.