ngin - Norfolk Genetic Information Network

8 May 2002


The main finding in the study might seem somewhat obvious - not in the world of organic slander ( Indeed the study itself is already being spun with headlines like: 'Pesticides haunt 'organic' fruit, vegetables'. Summary of study at:



May 7, 2002

EUGENE, Ore. -- The debate has raged for years:  Do organically grown foods contain fewer pesticides than conventionally raised foods?  According to a just-released, major research study, the answer is a resounding yes.  The study is the first, detailed comparative analysis of pesticide residue data for produce grown organically and conventionally.

The research team included scientists from the Organic Materials Review Institute (OMRI), an independent organic-agriculture research, education and evaluation organization headquartered in Eugene, Ore., and Consumers Union (CU), the Yonkers, N.Y.-based publisher of Consumer Reports magazine.  The team's findings were released May 8, 2002, in the peer-reviewed journal Food Additives and Contaminants.

The researchers analyzed test data on pesticide residues in more than 94,000 organic and non-organic food samples of some 20 different crops tested over nearly a decade.  Data were obtained from three independent sources: tests undertaken by CU in 1997 on selected foods; surveys conducted by the Pesticide Data Program of the U.S. Department of Agriculture on residues in a wide array of foods available on the U.S. market; and California Department of Pesticide Regulation surveys of residues in foods sold in California.

"Our research confirms what organic farmers have known all along, but now we have the data to back it up," said Brian Baker, Ph.D., OMRI research director and the study's lead researcher.  "Organic food clearly offers consumers the best choice to avoid pesticides in their diets."

The study was co-authored by Baker, along with OMRI board member Charles M. Benbrook, Ph.D., Benbrook Consulting Services; Karen L. Benbrook, M.S., Ecologic, Inc.; and Edward Groth III, Ph.D., senior scientist at Consumers Union.

Research Highlights

The USDA data showed that 73 percent of conventionally grown produce had at least one pesticide residue, while only 23 percent of organically grown samples of the same crops contained residues. More than 90 percent of USDA's samples of conventionally grown apples, peaches, pears, strawberries and celery had residues. Conventionally grown crops were also six times as likely to contain multiple pesticide residues.

In California state testing, residues were found in nearly a third of conventionally grown foods, but in only 6.5 percent of organic samples.  The researchers remarked that the California data were based on tests with less-sensitive analytical methods than those used to generate the USDA data, and hence, did not include many low-level residues detected by the USDA's
testing methods.

California testing also revealed multiple pesticide residues nine times more often in conventional samples than in organic samples. CU's tests found residues in 79 percent of conventionally grown samples and in 27 percent of organically grown samples, with multiple residues six times as common in the former.

"Our team was struck by the consistency of the pesticide residues reported in three very different datasets.  We now can say with confidence that organic farming systems help reduce exposure to pesticides in the human diet," Benbrook explained.

CU's Groth concurred: "Our findings are clear and compelling," he said. "These results are good news for consumers looking for way to minimize pesticide exposures."

While fewer pesticide residues were found on all organic samples, some might question why there were any residues found at all.  According to Baker, "organic" is not a pesticide-free claim, due to many factors beyond the control of the organic farmer.  Most residues in organic samples appear because of pesticide spray drift from adjacent fields, or soil or irrigation-water contamination, he noted.

"Mislabeling and occasional fraud also clearly account for some of the organic samples that tested positive for residues," Baker said.  As an example, he referred to a Mexican sample of "organic" sweet bell peppers that contained six different pesticide residues.

Implications of Research

The researchers noted that organic farming systems offer both organic and conventional farmers proven methods to lessen pest populations and pesticide use, and thus, also reduce the pesticide risks faced by farm workers and consumers.

"Based on my experience studying the impacts of federal pesticide laws and regulations, I am convinced that pest management innovation will reduce pesticide risks faster and more decisively than regulation," Benbrook said.

"Clearly, organic farmers are well represented among those breaking the trail toward more biologically based, low-risk pest management systems." The researchers also noted that organic farmers and certifiers could benefit from routine access to information on pesticide residues found in organic food samples tested by government programs.  Early detection of residues would help certifiers, growers, and the organic food trade identify and deal with instances and locations where pesticide drift or soil contamination is leading to detectable residues in organic foods.

A summary of the study, as well as charts and tables that illustrate study results, can be found at and at
The public can purchase a copy of the paper from the Food Additives and Contaminants website,

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