Of the 30 most commonly used lawn pesticides, 24 are toxic to fish and aquatic organisms.
Secondary poisoning from rodent baits is a significant cause of raptor (predatory birds) poisoning in areas of heavy use.
Quick-acting synthetic fertilizers cause euthrophocation (lack of oxygen), algal blooms, and closures of beaches and shellfish ground. Toxic blue-green algal blooms are exacerbated by nitrogen fertilizer runoff, making waters toxic to wildlife, pets, and humans
Common landscape insecticides such as Carbaryl (active ingredient in Sevin®), Imdicloprid (active ingredient in Bayer Advance Insect Control®), and Permethrin (active ingredient in tick sprays) are all deadly to fish and shellfish. Shellfish are filters for the environment, helping to break down algae and bacterial growth. Small marsh fish such as Killifish act as predators to mosquito larva.
Common landscape herbicides such as Glyphosate (active ingredient in Roundup®) and 2,4-D (Active ingredient in Weed-B-Gone®) are toxic to aquatic vegetation such as marsh grass. This vegetation acts as a buffer between lawns and the aquatic environment, filtering out chemicals and helping stabilize shoreline erosion.