Study says organic milk less tainted by pesticides

Residue detected in conventional samples

Results from a study examining what’s in organic versus conventional milk show that the majority of samples of conventional milk tested positive for low, chronic levels of pesticides, illegal antibiotics and growth hormones. The organic samples tested at either much lower or nonexistent rates.

“To our knowledge, the present study is the first study to compare levels of pesticide in the U.S. milk supply by production method (conventional vs. organic),” the researchers said. “It is also the first in a decade to measure antibiotic and hormone levels and compare them by milk production type.”

Ron Erskine, a professor at Michigan State University, who reviewed the study at USA TODAY’s request, expressed caution about overinterpreting the results because researchers used a method not approved by the FDA. All samples tested below FDA tolerance levels, except for one.

The study, conducted by Emory University in Atlanta, was funded by the Organic Center, a Washingtonbased nonprofit research organization, and looked at a total of 69 samples of conventional and organic milks pulled from retail stores around the USA. The results were published online June 26 by the peer-reviewed journal Public Health Nutrition.

Antibiotic residue was detected in 60% of conventional milk samples but not in the organic. Among the antibiotics detected were sulfamethazine and sulfathiazole. Both have been outlawed for use in milk-producing cattle.

Pesticide residue was found in up to 60% of conventional samples and none of the organic samples. Those included atrazine, chlorpyrifos, cypermethrin, diazinon and permethrin.