Neonicotinoids in U.S. Maize: Insecticide Substitution Effects and Environmental Risk

Abstract

This study exploits a novel dataset containing more than 89,000 farm-level surveys over a 17-year period to investigate how neonicotinoid seed treatments in maize, now ubiquitous, have affected the use of other insecticides. Neonicotinoid insecticides are the most used class of insecticides in the world, but they are controversial because of their high toxicity to honeybees. In the United States, maize production accounts for the majority of neonicotinoid use, mostly as seed treatments. We find that neonicotinoids substituted for other major insecticides: plots planted with neonicotinoidtreated seeds were 52% and 47% less likely to be treated with a pyrethroid and organophosphate insecticide, respectively. Although honeybees have been put at greater risk by neonicotinoids, the changed pattern of pest control instruments has reduced toxicity risk for mammals, birds, and fish. We also find that adoption of genetically engineered insect-resistant maize varieties significantly reduced the use of organophosphate and pyrethroid insecticides, thereby reducing toxicity exposure to all examined taxa. Policies aimed at restricting neonicotinoid use may need to account for undesirable unintended consequences.

Insecticides, more than herbicides, land use, and climate, are associated with declines in butterfly species richness and abundance in the American Midwest

“…The area-treatment measure based on broad practice classes is consistent with recent empirical results on patterns of substitution and complementarity in pest control markets 24,32,33 , allowing deeper insights into how changes in pesticide markets or policy might affect the overall threat to specific insect populations.…”

“…Crop Reporting Districts (CRDs) level and link this measure to county-level cropland land cover data to derive an annual county-level area-treatment metric. The area-treatment measure based on broad practice classes is consistent with recent empirical results on patterns of substitution and complementarity in pest control markets 24,32,33 , allowing deeper insights into how changes in pesticide markets or policy might affect the overall threat to specific insect populations.…”

“…Analyses of insect declines that focus on a single active ingredient can be misleading if they omit other correlated drivers of decline for two reasons. In the United States during 2004-12, corn and soybean farmers rapidly adopted glyphosate, Bt genetics, and neonicotinoid-treated seeds while use of other pest control technologies declined due to substitution effects 23,24 . As multiple pesticides may affect insect declines by one or more channels, each of these variables must be included if an analysis is to avoid omitted variable bias [25][26][27] or be useful for forecasting the potential impacts of pesticide regulations.…”

Trading risk for ambiguity: Production versus health under pesticide application

“…This is further supported by the fact that most U.S. farms are family run (ERS, 2006), and most pesticide users are farmers (Wilson & Tisdell, 2001). Hence, although the health externality associated with pesticide use is important (Harper & Zilberman, 1989; Paul et al, 2002; Perry & Moschini, 2020; Pimentel et al, 1992; Pimentel & Burges, 2014; Tilman et al, 2002; Wilson & Tisdell, 2001), this article investigates the private, rather than the social, optimal choice of pesticide among farmers.…”

Bifenthrin Baseline Susceptibility and Evaluation of Simulated Aerial Applications in Striacosta albicosta (Lepidoptera: Noctuidae)

“…For Kansas and Canada there is no information available for the percentage of the current use of pyrethroids, but it is registered every year for use to manage S. albicosta (Farhan et al 2017). Pyrethroid insecticides have been used for more than 40 yr and along with organophosphate insecticides account for the vast majority of applied insecticides in terms of volume and acres (Perry and Moschini 2019).…”