US EPA: negligible benefits of neonicotinoid seed treatments to soybean production

The Biological and Economic Analysis Division (BEAD) analyzed the use of the nitroguanidine neonicotinoid seed treatments for insect control in United States soybean production. Imidacloprid, thiamethoxam, and clothianidin are applied to seeds at mostly downstream seed  treating facilities prior to distribution to growers prior to planting. BEAD concludes that these seed treatments provide negligible overall benefits to soybean production in most situations. 

 

Published data indicate that in most cases there is no difference in soybean yield when soybean seed was treated with neonicotinoids versus not receiving any insect control treatment. Furthermore, neonicotinoid seed treatments as currently applied are only bioactive in soybean foliage for a period within the first 3-4 weeks of planting, which does not overlap with typical periods of activity for some target pests of concern. This information, along with current usage data, suggests that much of the existing usage on soybeans is prophylactic in nature. 

 

Multiple  foliar insecticides are available in instances where pest pressure necessitates a pest management  tactic and such foliar insecticides have been found to be as efficacious as neonicotinoid seed treatments for target pests. These alternatives to neonicotinoid seed treatments include foliar sprays of organophosphates ( acephate, chlorpyrifos ), synthetic pyrethroids (bifenthrin, cyfluthrin, gamma-cyhalothrin, lamba-cyhalothrin, deltamethrin, esfenvalerate, zetacypermethrin, permethrin), neonicotinoids (imidacloprid, thiamethoxam, clothianidin), and therecently registered sulfoxaflor, which works in a similar way to neonicotinoids.

 

In most cases, these alternatives are comparable in cost to one another and to neonicotinoid seed treatments. The cost of application was considered in this comparison, although because these alternatives can be tank-mixed with other chemicals that are typically applied to soybeans, additional passes over a field would not be necessary. In comparison to the next best alternative pest control measures, neonicotinoid seed treatments likely provide $0 in benefits to growers and at most $6 per acre in benefits (i.e., a 0%-1.7% difference in net operating revenue). Some neonicotinoid seed treatment usage could provide an insurance benefit against sporadic and unpredictable pests, particularly in the southern United States. However, BEAD did not find information to support the real-world significance of this benefit, and overall evidence indicates that any such potential benefit is not likely to be large or widespread in the United States.