Safe Metal Levels in Wines From Italy, Brazil, Argentina

Wines from three of the 15 nations studied had safe levels of heavy metals: Italy, Brazil, and Argentina.

Based on the maximum THQs for wines from each nation, here's the list of the worst offenders:

• Hungary
• Slovakia
• France
• Austria
• Spain
• Germany
• Portugal
• Greece
• Czech Republic
• Jordan
• Macedonia
• Serbia

Hungary and Slovakia had maximum potential THQ values over 350. France, Austria, Spain, Germany, and Portugal -- nations that import large quantities of wine to the U.S. -- had maximum potential THQ values over 100.

Argentinean and Italian wines did not have significant maximum THQ values.

"If you buy a bottle of wine, the only thing it tells you on the label is the amount of alcohol. I like the idea of labeling wines with the amounts of heavy metals they contain," Naughton says. "Many wines don't have these metals. So let customers vote by choice whether they want the heavy metals."

Where do the heavy metals come from? That's unknown. Naughton says possible sources include the soil of the vineyards in which the wine grapes are grown, the fungicides sprayed on the grapes, and possible contaminants in the yeasts used to ferment the wine.

Naughton and Petroczi did not directly measure heavy metals in the wines, but calculated THQs from data published in scientific journals. Since there was no data on heavy metals in U.S. wines, they did not include North American wines in their analysis.

Weiss says he'd like to see such data. He'd be interested to see whether national health databases can link health problems to daily wine consumption, and whether wine drinkers have higher concentrations of heavy metals in their bodies than teetotalers do.

In their paper, Naughton and Petroczi note that drinking red wine has been linked to health benefits because it contains antioxidant compounds.

"However, the finding of hazardous levels of metal ions which can be pro-oxidants leads to a major question mark over the protective benefits of red wine," they suggest.

The findings appear in the Oct. 29 issue of the open-access Chemistry Central Journal.

SOURCES: Naughton, D.P. and Petroczi, A. Chemistry Central Journal, Oct. 29, 2008; vol 2. Naughton, D.P. Chemistry Central Journal, June 25, 2008; vol 2. Declan P. Naughton, PhD, professor of biomolecular science, Kingston University, London. Bernard Weiss, PhD, professor of environmental medicine, University of Rochester, N.Y.