Earlier this week, NAAA submitted comments to the Environmental Protection Agency (EPA) on the biological evaluations for the reregistration of two triazine herbicides: atrazine and propazine. The EPA is required by FIFRA to review the registrations for all crop protection products every 15 years. As part of the reregistration process, the Endangered Species Act (ESA) requires that EPA work with the Fish and Wildlife Service (FWS) and National Marine Fisheries Service (NMFS) to evaluate the potential risks each pesticide represents to threatened and endangered species and their designated habitat. To accomplish this mandate, the EPA conducts a biological evaluation for each pesticide being evaluated during reregistration.
How these biological evaluations should be conducted has been a longstanding source of debate among the various parties interested in the matter. An interim method that was developed in 2015 was used for the evaluations of chlorpyrifos, diazinon and malathion. Based on feedback from those, the EPA released a revised method for conducting the evaluations in March of 2020. This revised method was used for atrazine and propazine.
Similar to human health and ecological risk assessments, the EPA once again used the Tier 1 model in AgDRIFT to estimate drift from aerial applications. NAAA referred the EPA to a letter submitted to the EPA’s Office of Pesticide Programs in June of 2020 for a detailed analysis of all the inaccuracies of the Tier 1 model and how to use the Tier 3 AgDRIFT model to improve the accuracy of aerial drift estimates. For atrazine, NAAA also commented that all buffer zones need to be based on the wind direction, as spray drift only moves downwind, not upwind.
In March NAAA will be commenting on the biological evaluation for glyphosate. NAAA will continue to monitor the pesticide registration review process to make sure aerial applications remain on pesticide labels.
