The U.S. Environmental Protection Agency issued a proposed interim registration decision on atrazine that includes mandatory spray drift control measures and other label updates.

The proposal is part of the agency’s re-registration review of atrazine, as well as propazine and simazine.

For atrazine, the Proposed Interim Decisions includes the following measures to mitigate aggregate human risk:

• Reduce the permissible application rates for use of granular and liquid formulations on residential turf from 2.2 pounds active ingredient per acre to 2 pounds per acre.

• Require additional personal protective equipment and engineering controls for certain uses.

• Restrict aerial applications to liquid formulations only.

• Restrict impregnation of dry bulk fertilizer for use in agricultural settings to 340 tons per worker per day.

• Require a minimum water volume of 87 gallons in handgun spray application via backpack spray to spot treatments only and require personal protective equipment.

• Prohibit mechanically pressurized handgun application to sweet corn, macadamia nuts and guava.

• Require mandatory spray drift reduction measures, add a non-target advisory statement to labeling and to adopt a nationwide stewardship program.

For propazine, the PID proposes to cancel the greenhouse use to mitigate aggregate human risk. Ecological risks would be mitigated by proposing to require various spray drift reduction measures and by adding a non-target advisory statement to labeling.

For simazine, the PID includes the following measures to mitigate aggregate human risk:

• Cancel simazine use on residential turf.

• Require additional personal protective equipment and engineering controls for certain uses.

• Limit pressurized handgun applications to certain commodities to spot treatment only.

• Ecological risks would be mitigated by proposing to require various spray drift reduction measures and by adding a non-target advisory statement to labeling.

EPA’s proposed decision is based on the 2016 draft ecological risk assessment and the 2018 human health draft risk assessment for atrazine.

EPA will be taking comment on the atrazine, propazine and simazine PID for 60 days after publication in the Federal Register.

On average, approximately 58% of field corn or 53.3 million acres are treated with 62.3 million pounds of atrazine per year, according to the EPA.

Corn growers on average made 1.2 applications of atrazine per year, with the average single application rate of 0.95 pounds active ingredient per acre.

About Atrazine

Atrazine is a widely used herbicide that can be applied before and after planting to control broadleaf and grassy weeds. Atrazine is a member of the triazine chemical class, which includes simazine and propazine. It is primarily used in agriculture, with the greatest use on corn, sorghum, and sugarcane. To a lesser extent, it is used on residential lawns and golf courses, particularly in Florida and the Southeast.