Neonicotinoids and their impact

What are neonics?

Neonicotinoids, commonly referred to as neonics, are a class of neuro-active insecticides that have become pervasive in modern agriculture. Chemically similar to nicotine, these insecticides have become the most widely used pesticide in the world for their effectiveness in controlling a variety of pests such as aphids, whiteflies, and other sap-feeding insects. Initially, neonics were celebrated for their broad-spectrum activity, systemic properties—requiring only one application per season—and perceived low toxicity to mammals. Newer research shows neonics have spread to bodies of water where they’ve damaged some aquatic ecosystems. Their widespread use has also raised questions about potential health risks.

Understanding the impact of neonic insecticides

Neonics were first introduced in the late 1990s, quickly becoming a go-to solution for farmers facing persistent pest problems.

These insecticides are primarily applied as seed treatments, foliar sprays, and soil applications. When used as a seed treatment, neonics coat the seed and are absorbed into the growing plant, becoming an integral part of the plant’s tissue.

Neonic use over the years

1990s

Neonics are introduced, quickly becoming a go-to solution for farmers fighting persistent pest problems. Their cost-effectiveness and single-use application increased their use.

2000s

By 2000, roughly 30% of field corn in the United States is treated with neonics. Use on soybeans was slow at first, but later became more popular.

2010s

At the start of the 2010s, approximately 80% of corn was treated with neonics. By 2014 nearly all corn seed in the U.S. and half of soybean seeds were being treated.

What’s at Risk?

Widespread and persistent use of neonics has raised alarms among environmental scientists, entomologists, and public health specialists.

It’s nearly impossible for farmers to avoid planting neonic-treated seeds for conventional crops like corn

While neonics have proven very effective at dealing with pests, their impacts on non-target species like bees and other pollinators. Neonics have contributed to alarming declines in insect populations, especially in regions where neonics are heavily used.

Neonics have been detected in water bodies across the country. These chemicals are highly soluble and can easily move from their initial application sites through surface runoff and leaching, particularly in sandy soils. In Wisconsin neonics have been found in over 5% of drinking water wells in agricultural areas and 69% of sampled irrigation wells. This offsite movement has serious implications for aquatic ecosystems, where neonics can harm species like mayflies, which are a critical food source for fish populations. 

Questions about usefulness

Recent research has questioned how useful neonics really are. For example, a 2021 study by Cornell University found that neonic use showed no corn yield benefit 83% of the time across 15 states. This raises the question of whether the environmental and public health risks associated with neonics justified their widespread use. 


Join us and partners for the first-ever Wisconsin Neonic Forum coming this fall!
Neonicotinoids, or neonics, are the most widely used insecticides in Wisconsin, applied to millions of acres of agricultural and urban land each year. What benefits do they provide and what risks do they pose? Attend this statewide forum to learn more about where these chemicals are used, how Wisconsin is regulating them, and more.