In early March, the Environmental Protection Agency (EPA) announced that additional training is required for certified applicators that work with herbicides that contain paraquat. The reason for these new restrictions is to help reduce accidental ingestion (since a single sip can be fatal) and other dangerous exposures to the product.

Data collected since 2000, shows 17 deaths have been caused by the accidental ingestion of paraquat. Many of these deaths resulted from people illegally transferring the pesticide to beverage containers and the victim later mistaking it for a drink. In addition to the deaths by accidental ingestion, three more deaths and many severe injuries have been caused by the pesticide getting onto the skin or into the eyes of those working with it during the past 18 years.

Long-Time Weed Control Standby

Back in 1967, the labeling of paraquat for weed control with soybeans and corn by Chevron Chemical led to the rapid acceptance and success with no-till. Through the mid-1970s, this contact herbicide was used by thousands of no-tillers to burndown small broadleaves and grasses and suppress perennial weeds by destroying the green foliage prior to no-tilling corn or beans. A popular weed control program for no-till corn in those days included paraquat as a burndown combined with atrazine and princep for residual weed control.

Since paraquat only burned down existing vegetation and did not translocate to the roots of weeds, the introduction of glyphosate in 1976 soon replaced paraquat as the most popular burndown herbicide for no-tillers.

Paraquat still has a place in certain no-till situations today and has not been totally replaced by glyphosate. And if the use of glyphosate is ever limited, paraquat could make a comeback in a number of no-till situations.

New Rules For Restricted Use Herbicide

Products on the market today that contain paraquat dichloride as an active ingredient include Gramoxone, Firestorm, Helmquat and Parazone.

Kerry Richards, a pesticide safety education program coordinator at the University of Delaware, says companies are required to have only newly labeled product in the market after Nov. 14, 2019. In addition, manufacturers are being required to pursue additional registrations for closed system packaging with paraquat herbicides.

“The best advice still remains to read and follow the label directions on the product you are using, keep the product in its original packaging and never put product in any type of food container, especially a drink container,” says Richards.

The new restrictions require that only certified applicators can mix, load and apply the herbicide. Application “under the direct supervision” of a certified applicator is no longer allowed.

The requirement for training, which must be repeated every 3 years, is only one of several actions the EPA has taken to prevent poisonings with the new label changes.

Richards says EPA is allowing the sale of paraquat that is already in the trade so some paraquat sold this growing season may not have the new training requirement listed on the label. However, if the new training requirement is listed on the label, training must be completed before use.