EPA issues Interim decision on herbicide paraquat dichloride

After a nine month review, the US Environmental Protection Agency (EPA) recently issued an interim decision (ID) on the herbicide paraquat dichloride (paraquat). In October last year, the EPA proposed to prohibit paraquat spraying in the air (except for cotton drying purposes), and the interim decision issued this time allowed the aerial spraying of all approved crops, but at the same time, the agency also formulated specific restrictive measures to protect human health. For example, when spraying in the air, a buffer zone of 50 to 75 feet should be set around the house.

Paraquat is a herbicide, which can be used to control invasive weeds in crops such as cotton, corn and soybean. At present, there is no direct substitute for paraquat. In the United States, all paraquat products are restricted products and can only be used by certified pesticide applicators.

EPA has taken positive measures to ensure that the use of paraquat will not cause unreasonable adverse effects on human health or the environment, and comply with the label instructions. The paraquat human health mitigation decision issued by EPA in 2016 includes a safety awareness action, training for paraquat users and changes to labels and product packaging to help prevent diseases, injuries or deaths caused by improper use of paraquat.

The interim decision issued this time builds on previous work, including the following executable mitigation measures, which specify application parameters and establish restrictions to further protect individuals from exposure. EPA has determined that these mitigation measures are necessary to address the exposure risk of paraquat and allow the continued use of this important agricultural tool.

·Restrictions on air applications require residential buffers.

Prohibition of the use of high pressure pistols and Knapsack sprayers.

·Closed cab or respirator is required for ground spray bar applications.

·Increase the restricted entry interval (REI) of several crops.

In addition, the EPA evaluated hundreds of studies, including published toxic and epidemiological literature on paraquat exposure and adverse health consequences, including Parkinson’s disease. There are many studies on paraquat and Parkinson’s disease with uneven quality and contradictory results. According to EPA’s literature review in 2019, the latest study of an agricultural health research cohort was published in 2020, which reported that there was no association between paraquat exposure and Parkinson’s disease. It is worth noting that this updated study does not duplicate the findings of AHS considered by EPA in early 2011 and indicates that there may be a potential association. According to the requirements of FIFRA, after a thorough review of the best available science, EPA has not found a clear link between paraquat label use exposure and adverse health outcomes such as Parkinson’s disease and cancer.

The new safety measures announced this time will significantly reduce potential human health risks and protect all potential human health outcomes, including Parkinson’s disease.

Source: World agrochemical network

Post time: Aug-13-2021