US EPA to impose atrazine restrictions

Abstract

The US Environmental Protection Agency is proposing new mitigation measures to protect aquatic environments from the widely used herbicide atrazine. If finalized, the measures would reverse a 2020 policy decision implemented by the Donald J. Trump administration that loosened restrictions for growers near rivers and streams. Under the EPA’s proposal, growers located in watersheds with atrazine concentrations that exceed 3.4 μg/L would have to reduce either runoff or application rates. That level is far lower than the 15 μg/L threshold adopted by the Trump administration. The EPA determined the 3.4 μg/L level of concern in a 2016 ecological risk assessment. When the concentration is exceeded, atrazine has a 50% chance of negatively impacting aquatic plants. The EPA also proposes prohibiting all growers from using atrazine when soils are saturated with water, during rain, or when storms are forecast within 48 hours. All growers would also be prohibited from aerial spraying