Questions & Answers


	Questions & Answers Glossary

What are EBDCs?
What is ETU?
How do EBDCs function?
I'm concerned about EBDC or ETU residues on my fruits and vegetables. What can I do?
What evidence do you have to support the safety of EBDC fungicides?
Why are EBDCs reviewed as a class when other chemicals are reviewed individually?

What are EBDCs?
Ethylenebisdithiocarbamate (EBDC) fungicides are a group of organic fungicides used to control a broad spectrum of fungal diseases such as rots, molds, or scab, in fruit, vegetable, field and ornamental crops. The EBDC group consists of mancozeb, maneb, and others.

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What is ETU?
Ethylenethiourea (ETU) is a common metabolite, minor impurity, and degradate of all EBDCs.

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How do EBDCs function?
EBDCs are known to disrupt the respiratory functions of target fungi at several points along the metabolic pathway. Because of the multi-site activity, no resistance has been seen with EBDCs even after over 50 years of use.

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I'm concerned about EBDC or ETU residues on my fruits and vegetables. What can I do?
EBDCs stay on the surface of plants to protect against fungal infection. EBDCs are not systemic agents, that is, they are not absorbed inside the plant. Because the EBDCs remain on the surface of the crop, the residues can be readily removed from harvested crops by normal food preparation practices such as washing, peeling, trimming, etc.

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What evidence do you have to support the safety of EBDC fungicides?
Beginning with studies dating all the way back to the 1940s, there is a large body of evidence to support our conclusion that EBDCs are safe when used according to federally approved label instructions. These studies show:

Forty years of use without any episodes of significant injury to man or the environment
Residue levels consistently below levels considered safe by the federal government
Most residues of those are removed by general practices such as washing, peeling and trimming that are followed in homes, restaurants and commercial food processing plants
No deaths or increases in disease or chronic adverse health effects have been established by the many health studies of various exposed groups
EBDC products and their common metabolite ETU are biodegradable and will not accumulate, persist, or accrue to significant levels in man or the environment

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Why are EBDCs reviewed as a class when other chemicals are reviewed individually?
The Food Quality Protection Act requires EPA to consider the effects of cumulative toxicity of pesticides in their assessment of the safety of pesticide residues in food. Cumulative risk assessments are to be considered for compounds having a common mechanism of toxicity.

The EBDCs are the classic example of cumulative toxicity because they have been regulated as a class in the United States on the basis of their common metabolite ETU.

A September, 2001 SAP meeting concluded that there was no basis for adding other chemicals to the common mechanism group and that EPA should continue their past practice of regulating the EBDCs as a group due to the common metabolite ETU. View the SAP report for further information.

EPA agreed with the SAP recommendation. Therefore, the EBDCs will continue to be regulated as a class.

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