EPA: 2,4-D Occupational and Residential Risks ‘Not of Concern’

WASHINGTON, D.C. – The Environmental Protection Agency (EPA) this week released its comprehensive assessment of the herbicide 2,4-Dichloro-phenoxyacetic acid, commonly known as 2,4-D, under the agency’s re-registration program. The pesticide industry is pleased with the EPA’s determination that 2,4-D does not present risks of concern to human health when users follow product instructions correctly. The conclusion is outlined in EPA’s 320-page 2,4-D Re-registration Eligibility Decision (RED) document available by clicking here.

“Overall, this is just good news for our industry,” says Angela Bendorf Jamison, a pesticide industry representative. “We always hear negative feedback about pesticides, but those viewpoints aren’t always based on factual information. Now, the re-registration through the EPA shows that the safety of 2,4-D is based on science. It’s proof that these products can be used safely without posing a risk to human health.”

The Agency's announcement and release of the RED on 2,4-D completed a 17-year EPA review process of the widely used pesticide. 2,4-D is a phenoxy herbicide discovered 60 years ago and is used worldwide for a wide variety of applications in agricultural, non-crop, residential, and aquatic settings. The EPA concluded that acute and short-term margins of exposure for homeowner applications of 2,4-D to lawns were “not of concern.”

Task Force members include Dow AgroSciences (U.S.), Nufarm (Australia), and Agro-Gor Corp., a U.S. corporation jointly owned by Atanor, S.A. (Argentina) and PBI Gordon Corp. (U.S.). The companies all hold technical registration for 2,4-D under the Federal Insecticide Fungicide and Rodenticide Act (FIFRA).

ABOUT THE DATA REVIEW. Facilitating the research over the last 17 years was the Industry Task Force II on 2,4-D Research Data, which developed and submitted more than 300 Good Laboratory Practice (GLP) toxicology, environmental and residue studies to the EPA. EPA scientists reviewed the data to assess the herbicide's safety under FIFRA and the Food Quality Protection Act (FQPA).

“The re-registration process began in 1988 and I’ve been involved since the beginning,” said Larry Hammond, chairman of the technical committee for the Task Force. Hammond shared with Lawn & Landscape some of the reasons why the re-registration process took such a long time. “The registration standard indicated that by 1996, the process should have been complete and the Task Force, in fact, had that date set and had all of our studies submitted as required by December 1995,” Hammond explains. “We were expecting the review process to be finished by 1998 at the latest; however, in August 1996 the FQPA was signed, which reprioritized the re-registration of all kinds of different compounds.”

Hammond explains that the FQPA required carcinogenic or possible carcinogenic compounds to be re-registered with the EPA first, followed by organophosphates and carbamates. “Herbicides were pushed farther down the line – almost to the bottom of the list,” he says. “There’s significance in that regarding 2,4-D because it meant that insecticides and all the other compounds were of more concern than herbicides.”

Eventually, the EPA’s focus came back to 2,4-D. During the time between the initiation of the re-registration process and this week’s announcement, Hammond says the Task Force maintained ongoing research on certain aspects of the herbicide, such as crop residue studies. Ultimately 2,4-D received a thumbs-up from the EPA.

“The EPA’s assessment of the human and environmental scientific data reinforces a growing number of regulatory decisions and expert reviews that conclude the use of 2,4-D according to product instructions does not present an unacceptable risk to human health or the environment,” said Don Page, assistant executive director of the Industry Task Force II on 2,4-D Research Data. “EPA’s comprehensive findings are consistent with decisions of other authorities such as the World Health Organization, Health Canada, European Commission and recent studies by the U.S. National Cancer Institute on 2,4-D.”

EPA's RED assessment included a review of animal and human data, the latter in the form of epidemiology studies (the study of the incidence of disease in populations). EPA noted that it reviewed epidemiological studies linking 2,4-D to cancer twice in the past. In the first review in January 2004, EPA concluded that there was “no additional evidence that would implicate 2,4-D as a cause of cancer.” The second review in December 2004, authored by EPA scientists Jerry Blondell, found that “none of the more recent epidemiological studies definitively linked human cancer cases to 2,4-D.”

IMPORTANCE TO THE INDUSTRY. 2,4-D, one of the most widely used herbicides in the U.S. and worldwide, is applied to crops such as wheat, corn, rice, soybeans, potatoes, sugar cane, fruits and nuts. In the green industry, it’s best known for its control of invasive species in aquatic and federally protected areas, as well as on broadleaf weeds in turf.

Many practicing lawn care operators may not remember a time in their business when 2,4-D wasn’t under review, but Hammond says applicators have little to concern themselves with regarding product label changes. “Overall we’ve maintained all the uses that were on the label before – including the aquatic uses, which required a good deal of communication between Agency representatives and community representatives. However, there have been some refinements based on testing,” he says. “One adjustment is that the maximum application rate has been reduced from 2 pounds per acre to 1.5 pounds. This is just a slight reduction and most applications use less than a pound, so many applicators won’t be affected.” Hammond also noted that new crop uses have been added to the label – a change that will be of higher interest in the agricultural market.

So, will the EPA approval eliminate arguments against 2,4-D by environmental activist groups? Not likely; however, Frank Gasperini, director of state issues for Responsible Industry for a Sound Environment, told Lawn & Landscape that EPA approval of 2,4-D should put consumers’ concerns to rest. “There are a number of activist organizations against the use of 2,4-D for the basic reason that it’s a pesticide,” Gasperini says. “The media has had a tendency to pick up on reports from those groups that claim issues such as a link between 2,4-D and cancer among dogs whose owners hire lawn care services, but those statistics don’t always hold up. Now that the EPA has formally said that no credible link exists, it should make the industry and our customers very comfortable that such a highly useful product will continue to be available.”

Hammond adds that arguments against the validity of the data also will be difficult to make. “The activists have always said that you can’t really believe these companies because they do their own work, they fund the Agency and they question whether the data hasn’t in some way been altered,” he says. “The response that you can take home for that is that we have used as many as 30 different government-rated laboratories that follow Good Laboratory Practices for all of the information. The Task Force members themselves have not done the studies – they’ve been done by third parties and they’re all done under Good Laboratory Practices which are outlined by the government.”

Gasperini says 2,4-D is an effective herbicide and that its low price helps preserve the ability to have well-maintained lawns across economic boundaries. “It would be a pity to eliminate the use of 2,4-D because it would limit the ability to maintain nice, safe, pleasant grounds in areas that couldn’t afford the use of a more expensive product,” he says. According to the U.S. Department of Agriculture, the loss of 2,4-D would cost the U.S. economy $1.7 billion annually in higher food production and weed control expenses.