Use and Status of Rotenone in Organic Growing

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Rotenone is a potent botanical pesticide that has become a source of mounting concern because of its toxicity and potential environmental impact. There is significant confusion concerning whether and how this material may be used in USDA-certified organic farming.

Although the Organic Materials Review Institute (OMRI) Generic Materials List identifies rotenone as “Allowed with Restrictions” on organic farms, the material is only legally allowed under certain conditions. Other substances commonly used with rotenone, including piperonyl butoxide, are explicitly prohibited for use in organic agriculture. The National Organic Program (NOP) is currently exploring possible changes to the regulations, potentially limiting or prohibiting the use of rotenone.

Rotenone is commonly derived from the roots of various tropical plants native to Southeast Asia, South America and East Africa. Historically, farmers have used this extract as a foliar spray to control pests on vegetables, berries, tree fruits, nuts, forage crops and sugarcane. It was first registered in the United States in 1947, and through the years, the Environmental Protection Agency (EPA) required a number of studies to further confirm its safety status for use in agriculture. In 2004, the EPA required an inhalation neurotoxicity study to further investigate the possibility of rotenone leading to Parkinson’s Disease-like symptoms at high dose exposure in animals. Instead, the companies distributing and selling rotenone products voluntarily cancelled all food use registrations for it, except for piscicide (fish kill) uses.  Since then, the EPA only supports registration for piscicidal purposes.

According to the U.S. organic regulations, natural substances (except for those appearing as prohibited in the regulations) may be used on organic farms. Rotenone is considered natural under these regulations, and, therefore, is compliant for use as a pesticide on organic farms. However, because the EPA is the governing regulatory agency for its legal sale and distribution in the United States, and it is no longer registered for uses other than for fish kill, it is not available for purchase by an organic producer in this country.

Although rotenone is unlikely to be in use on organic farms in the U.S., farms are certified organic all over the world under the U.S. organic regulations. Other countries may have different rules for whether rotenone may be used on agricultural land, so it is possible that the pesticide is used on certified-organic products being grown in other countries. These same certified organic products may be shipped to the U.S., and because rotenone is permitted by the U.S. organic regulations, they would not be in violation of any organic rule. 

The National Organic Standards Board (NOSB) is a citizen body that advises the National Organic Program (NOP) on the use of substances in organic production. Recently, the NOSB became aware that rotenone is still being used in foreign countries on certified-organic produce. Because of concerns for worker and human health in connection with rotenone, the NOSB subsequently recommended to prohibit the use of rotenone in organic production, effective January 1, 2016. They wanted to delay the prohibition by several years to allow those farms using rotenone to research suitable alternatives.

The NOP is responsible for carrying out NOSB recommendations through the regulatory process.  In this case, the NOP has informed the organic industry that they intend to consult with the EPA regarding the status of rotenone’s tolerance exemptions (the level at which pesticide residues are legally permitted by the EPA) on imported produce. They also received public comment from banana producers on the need for rotenone, and they intend to gather more information on rotenone’s current use in organic production before taking action on the NOSB recommendation.

Members of the public may submit comments when formal rulemaking on rotenone commences by visiting this NOP comments page. Rulemaking will be announced on the NOP website and through their “USDA Organic Insider” email newsletter. Sign up to receive updates on the newsletter registration page.

Thank you to OMRI Technical Director Lindsay Fernandez-Salvador for providing this guest blog post for MOTHER EARTH NEWS. She holds a B.S. from Oregon State University in Natural Resource Management and an M.S. from University of Florida in Geography. She has over 10 years of work experience on both conventional and organic farms.

Photos courtesy OMRI