ATF Testing Wines for Pesticide Residues

Wednesday, November 6, 2002
by Lynn Alley

In the not-too-distant future, consumers are likely to have assurance, courtesy of the Bureau of Alcohol, Tobacco and Firearms, that their favorite wines are free of harmful levels of pesticide residues.

For the past two years, ATF lab scientist Jon Wong has been refining methods for detecting residues of pesticides, herbicides and fungicides in wine. Wong has been routinely sampling imports, and this year, has added domestic wines to his testing program.

In addition to regulating such things as wine labels, the ATF regularly purchases random wines from retail shops around the country and analyzes them in it’s lab in Rockville, Md.  The program was originally designed to assess ethanol levels for taxation purposes, but over the years, it has been expanded to include other substances.

For example, in the late 1980’s, after the Chernobyl disaster, the lab began analyzing samples of wine from Eastern European countries for signs of radiation fallout and heavy metals. No radioactive residues were detected.

But Wong and his colleagues have been finding plenty of pesticides with their new testing program.  “Typically, we are finding one to three different types of pesticide residues in wines we’ve tested, but in one Eastern European sample, we recently found residues of seven or eight different pesticides,” said Wong.

Currently, there are no standards or maximum acceptable limits for pesticides in wine, although such limits exist for table grapes.  The ATF will pass its data on pesticide residues in wine to the Environmental Protection Agency, which already determines what pesticide levels are “safe” for consumers in fresh fruits and vegetables and will be responsible for the same in wine.

The most common insecticide that Wong finds is Carbaryl, known under the brand name Sevia to home gardeners. Commonly found fungicides include Procymidone, Iprodione, Myclubtanil and Metalaxyl. “These are all registered for use on grapes in the United States,” said Wong, “but we’ve also been finding traces of Oxadixl, a fungicide not registered for use on grapes in the U.S., in some wine imports.”

According to ATF lab director Sumer Dugar, “Once we’ve found evidence of unauthorized pesticide residues in wines, we have the authority to pull them off the market.”  However, Dugar said the ATF is not likely to do so without first consulting the EPA or the Food and Drug Administration, both of which are charged with the protection of consumer health.

In addition to providing important data to consumer protection agencies, Wong sees possible applications in certifying organic wines. At present, no provisions exist for residue testing of wines labeled as “organic” or made “from organically grown grapes.”

Wong cited a study done in 2000 in Switzerland on certified organic wines, in which many samples tested positive for a wide range of pesticide residues. “It is unclear how the pesticides got into the wines in the first place,” said Wong, “Whether so-called organic farmers were actually spraying their crops, or whether it was simply a case of pesticides being sprayed on some nearby field drifting into their organic vineyards, no one really knows.”