The widely used insecticides are well known for their effects on bees and other pollinating insects.
Neonicotinoid insecticides are widely used in agriculture; the chemical is applied to many of the seeds farmers plant. It s known as a systemic insecticide because as the plant grows, it takes up the insecticide with water and nutrients.
If an insect tries to eat the plant, it gets a lethal dose of insecticide. Concerns about the impact on pollinators is based on the fact the insecticide is also found in the pollen of flowering plants near farm fields where bees feed.
But the U of M study raises questions about potential environmental effects in lakes and rivers from persistent low levels of insecticides, and about the level of the chemicals in urban waterways.