Mancozeb Proposed Interim Registration Review Decision - Crop Cancellations and REI Changes

By Melanie L. Lewis Ivey, Associate Professor, Extension Fruit Pathologist, Department of Plant Pathology

In June, the EPA completed the proposed interim registration review for mancozeb. Mancozeb is a broad-spectrum fungicide widely used by fruit, nut, and vegetable growers to control many fungal diseases. Mancozeb is a multisite fungicide, which means it targets several biochemical pathways in fungi. This mode of action makes it more difficult for fungi to develop resistance compared to fungicides that target a singlesite. However, the EPA has identified risks of concern to human health and non-target organisms from the use of mancozeb and thus proposed the following measures specific to fruit crops to “ensure mancozeb use does not present unreasonable adverse effects for human health or the environment.”

• Cancellation of mancozeb use on all types of grapes (including table, wine, juice, and raisin).
• For aerial applications to orchards that are adjacent to residential area a 25-foot buffer zone from the edge of the treated field will be required.
• Closed-cab equipment plus gloves will be required for the airblast applicator scenario for the airblast applicator scenario for all formulations for orchards and vineyards.
• The use of an APF10 respirator and closed loading systems for aerial, chemigation, and ground-boomapplications utilizing dry flowable, wettable powder, and water-soluble packet formulations.
• Increase in restricted entry intervals (REIs) for pome fruit from 24 hours to 4 days for all activities.
• Prohibition of hand-thinning pome fruit crops.
• Mandates on droplet size.
• Spray drift buffers for fields adjacent to aquatic habitats and conservation areas depending on the application method:
  • Aerial applications – 50 ft
  • Ground boom applications – 15 ft
  • Airblast applications – 15 ft

The proposed deadline to submit comments to the EPA is September 16, 2024. This leaves very little time for the fruit industry to put together a strong argument for the retention of the registration of mancozeb for grapes and the retention of a 24- hour REI for apple and pears. The grape and tree fruit industries arestrongly encouraged to write a letter of request to extend the public comment period so that the industries have adequate time to develop a strong public comment. Requests can be emailed directly to Dr. Jean Overstreet (see contact information below). It is recommended that Mr. Ben Tweed be copied on the email.

A copy of the proposed interim registration review can be found at u.osu.edu/fruitpathology/fruitnews-2/.