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PMRA returns re-evaluation decision on mancozeb

The Pest Management Regulatory Agency (PMRA) has returned its decision for the re-evaluation of mancozeb. Under the authority of the Pest Control Products Act, the PMRA has determined that continued registration of products containing mancozeb is acceptable, with some exceptions and additional risk mitigation measures.

The following supported uses of mancozeb products meet current standards for human health and environment protection, and have value when used according to the revised conditions of registration:

• ground and aerial foliar application to potatoes;
• ground foliar application on apples, onions, sugar beets, ginseng, field cucumbers, field tomatoes, grapes, pumpkin, and squash;
• ground foliar application to melon, including cantaloupe but excluding watermelon; and
• in-furrow application to onions.

The following uses of mancozeb have been cancelled due to lack of support from the manufacturers:

• All seed treatments (including potato seed piece treatment);
• Greenhouse uses (in other words, tobacco, tomatoes);
• Use on pears, carrots, celery, lettuce, watermelon, lentils, wheat, alfalfa grown for seed;
• Ornamentals and forestry uses;
• All applications using any hand-held equipment;
• All end-use (commercial class) wettable powder or dust formulations.

Mancozeb belongs to the group of fungicides commonly known as ethylene bis (dithiocarbamates) (EBDCs). These EBDCs decompose to ethylene thiourea (ETU), which has been classified as a probable human carcinogen by the U.S. Environmental Protection Agency (EPA). There are also concerns that ETU causes birth defects and genetic mutations.

The proposed final re-evaluation decision for mancozeb was published on Oct. 5, 2018, which suggested cancelling all uses of mancozeb – except on tobacco – due to unacceptable risks to human health and the environment. This proposed decision removed the original exception from PMRA’s June 2018 re-evaluation that allowed for foliar application of mancozeb on potatoes.

For the full decision breakdown and list of additional mitigation measures, visit the PMRA website.