Neonicotinoid insecticides are currently applied to the majority of corn and soybean seeds in the United States. However, it is unclear how often farmers benefit from their use. In addition, neonicotinoid exposures can negatively impact beneficial organisms such as pollinators, yet to date no synthesis has quantified risk to pollinators in field crops settings. Here, we assess the economic value of neonicotinoid seed treatments by drawing on data from over 2,000 paired field trials that have compared the performance of a neonicotinoid-based insecticide to that of a chemical or non-chemical alternative. To assess risk to pollinators, we draw on data from over 300 studies that have measured effects from and/or exposure to neonicotinoid insecticides in or near seed-treated corn and soybean fields. Overall, 82-97% of field trials find no significant increase (or a decrease) in corn or soybean yield when neonicotinoid-treated seeds are compared to chemical alternatives or untreated controls. At the same time, usage of neonicotinoid-treated corn and soybean seeds results in risk to pollinators; 74% of neonicotinoid exposures are likely to impact honey bee physiology, 58% of exposures are likely to impact behavior, and 37% of exposures are likely to impact reproduction. These results indicate that usage of neonicotinoid treatments on corn and soybean seeds results in risk to pollinators but do not consistently provide benefits to farmers. We suggest that incentives and policies to reduce usage of neonicotinoid-treated seeds should address those products’ value as inexpensive crop insurance as well as pest management tools.
