A study by British researchers has revealed that many red and white wines produced in Europe contain potentially dangerous levels of toxic heavy metals.
Professor Declan Naughton and Dr Andrea Petróczi of Kingston University, London, calculated target hazard quotients (THQs) for the presence of seven metal ions (vanadium, chromium, manganese, nickel, copper, zinc, and lead) in wines from 15 countries in Europe, South America, and the Middle East. THQs provide an indication of risk associated with long-term exposure to chemicals based upon reference upper safe limits – a THQ of 1.0 or less is classed as safe however a THQ above 1.0 is considered to be potentially hazardous.
Results showed that most of the wines tested had THQs between 50 and 200 per glass, with some having a THQ as high as 350. Wines from Hungary and Slovakia contained the highest levels of heavy metal contaminants. Italy, Brazil, and Argentina were the only countries out of the 15 tested whose wine had THQs of 1.0 or less.
The findings do not suggest that drinking one glass of wine could be dangerous; however the researchers say that there is a “significant concern to health for people ingesting one 250 ml glass per day.”
The researchers conclude: “The results from this study also question a popular belief about the health-giving properties of red wine: that drinking red wine daily protects you from heart attacks is often related to levels of anti-oxidants. 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.”
Naughton DP, Petroczi A. Heavy metal ions in wines: meta-analysis of target hazard quotients reveal health risks. Chemistry Central Journal. 2008. doi:10.1186/1752-153X-2-22
