IARC Classification of 2,4-D Inconsistent with Government Reviews

INDIANAPOLIS — June 22, 2015 — The classification of the herbicide 2,4-D by the International Agency for Research on Cancer (IARC) is inconsistent with government findings in nearly 100 countries, including the U.S., Canada, U.K., Germany, France, Japan, Brazil and China, which have for decades affirmed the safety of 2,4-D when used according to approved labeling. Government reviews were based on rigorous hazard and risk evaluations of more than 4,000 scientific studies. In sharp contrast to the government reviews, IARC, an agency of the United Nations World Health Organization (WHO), reviews an incomplete set of information to focus solely on whether a substance or activity could be a carcinogen, not whether it is a carcinogen when used under real-world circumstances. The IARC classification, which is unchanged from the previous IARC review of chlorophenoxy herbicides, should not be mischaracterized in ways that are misleading and harmful to farmers and consumers. 

“No herbicide has been more thoroughly studied and no national regulatory body in the world considers 2,4-D a carcinogen,” said John Cuffe, Global Regulatory Sciences and Regulatory Affairs, Dow AgroSciences. “In fact, IARC stated that there is ‘inadequate evidence’ for human carcinogenicity. IARC’s findings on 2,4-D are not the last word even within the WHO, whose JMPR does not consider the handling and use of approved 2,4-D herbicides to pose a cancer risk.” JMPR is the Joint Meeting on Pesticide Residues, whose evaluations support establishment of world food standards.

As recently as October, 2014, the U.S. Environmental Protection Agency (EPA) affirmed that the herbicide is not a carcinogen based on a 17-year evaluation of relevant health and safety data. In 2009, Health Canada “found that 2,4-D does not increase the risk of cancer and can be used safely” if used according to label directions. And last year, the European Food Safety Authority concluded that 2,4-D was “unlikely” to “pose a carcinogenic risk to humans.”

“IARC has classified only one of about 1,000 agents and activities it has reviewed as ‘probably not carcinogenic to humans,’’’ said Cuffe. “IARC has classified products we use as potential carcinogens, including coffee, aloe vera, and pickled vegetables.”

For 70 years, 2,4-D has been widely used around the world to help protect crops, pastures and other areas from noxious and invasive weeds.

“I am very concerned that these IARC reviews will be misinterpreted by the general public,” said Ken McCauley, Kansas grower and past president of the National Corn Growers Association. “Herbicides like 2,4-D are essential to modern farming, helping us produce more food, control weeds, use less resources and reduce our costs, which ultimately helps the consumer,” said McCauley. “Based on all the studies and government reviews, we believe 2,4-D herbicides are safe or we wouldn’t be using them.”

For more information about 2,4-D, go to www.24d.reviews.


About Dow AgroSciences

Dow AgroSciences discovers, develops, and brings to market crop protection and plant biotechnology solutions for the growing world. Based in Indianapolis, Indiana, USA, Dow AgroSciences is a wholly owned subsidiary of The Dow Chemical Company and had annual global sales of $7.3 billion in 2014. Learn more at www.dowagro.com. Follow Dow AgroSciences on Facebook, Twitter, LinkedIn, and Google+, or subscribe to our News Release RSS Feed.


Additional Information:

Pesticide regulatory authorities have consistently concluded that despite extensive study, 2,4-D has not been shown to pose a risk of human cancer.

European Food Safety Authority, 2015: “…2,4-D, as currently manufactured, is unlikely to have a genotoxic potential or pose a carcinogenic risk to humans.” http://www.efsa.europa.eu/en/efsajournal/doc/3812.pdf

EPA, 2014: “While there has been much focus on epidemiology data suggesting a linkage between NHL and farm work, there is insufficient scientific evidence supporting a specific linkage with 2,4-D. Furthermore, this linkage is not supported by data on laboratory animals as discussed in the cancer assessment portion of this response.” http://www.regulations.gov/#!documentDetail;D=EPA-HQ-OPP-2014-0195-2414

Health Canada, 2009: “No other international regulatory body considers 2,4-D to be a human carcinogen. Based on all available and relevant data, Health Canada agrees with this position…Health Canada found that 2,4-D does not increase the risk of cancer and can be used safely by homeowners, provided label directions are followed.” http://www.hc-sc.gc.ca/cps-spc/pest/part/protect-proteger/24d/index-eng.php#physicians