The U.S. Environmental Protection Agency (EPA) is currently reviewing the registration of the fungicide Mancozeb, with proposed changes that may impact its use in grapes nationwide. This includes the potential removal of grapes from the approved label due to concerns about post-application worker exposure during activities such as hand-harvesting, leaf pulling, and tying. This article summarizes recent data from a 2024 Cornell-led survey and outlines what the proposed changes may mean for vineyards in New York and other Eastern states.
Why is Mancozeb under review?
Mancozeb is a multi-site, broad-spectrum fungicide long used by grape growers across the U.S., especially in the humid climates of the East where fungal and oomycete diseases are a major concern. As part of its FIFRA-mandated re-registration process, the U.S. Environmental Protection Agency (EPA) has proposed cancelling grapevine as an approved use site for Mancozeb by 2027 (Docket EPA-HQ-OPP-2015-0291 and supporting document EPA-HQ-OPP-2015-0291-0094). This proposal is based on concerns about post-application worker exposure to residues during certain vineyard activities. For more information about this PID, please see Cornell Grape Pathology’s August 2024 article.
The EPA identified specific tasks such as hand-harvesting, leaf pulling, and tying/training as high-risk if performed within 45 days of a Mancozeb application. These health concerns are considered as very serious by the EPA, and as such, they do warrant review and mitigation consideration. However, viticultural practices can vary significantly based on region, variety, and market segment. In response to the EPA’s proposed interim decision, Cornell Grape Pathology conducted a survey of 331 total grape growers, with 285 of whom self-identified as “Eastern grape growers,” which we defined as east of the Rocky Mountains. A full report of our survey data can be found here. The rest of this article will summarize and synthesize its findings.