The US Environment Protection Agency has proposed new measures to protect the aquatic environments from largely used herbicide atrazine. If finalized, the measures would reverse a 2020 policy implemented by the ex-government with 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 runoff or reduce their application rates. That level is far lower than the 15 μg/L thresholds adopted by the ex-government.

When the concentration is exceeded, atrazine has a 50% chance to create a negative impact on the aquatic environment. Atrazine is generally used on corn and other crops to control grass and broadleaf weeds. Since its usage creates developmental and reproductivity concerns, this herbicide is banned in European Union.

In addition to lower thresholds, EPA proposes a law to prohibit all growers from using atrazine during the rain, when soil is saturated with water, or when storms are announced within 48 hrs. Also, all growers would be prohibited from pneumatic spraying of atrazine.

Reference: https://cen.acs.org/environment/pesticides/US-EPA-impose-atrazine-restrictions/100/web/2022/07