Heavy metal wine: The comeback

Trade bodies and experts have spoken out against the report that states wine contains dangerous levels of “heavy metals”. The Food Standards Agency, the Wine & Spirit Trade Association, generic bodies and scientists all question the validity of the research published in the Chemistry Central Journal.

Yesterday’s db newsletter reported on the report’s findings that wine contains potentially dangerous levels of at least seven heavy metals, including manganese, which has been linked to Parkinson’s disease.

However, a number of authorities on the subject of wine composition are questioning the research’s findings.

Scientists at Boston University, R Curtis Ellison and Yuqing Zhang state: "The key problem with this paper is that you cannot use levels of any single constituent or group of constituents in wine to determine the long-term net effects on health."

Although Californian wines were not part of the research, the Wine Institute of California released a statement in response to the reseach. It said: "The authors did not perform their own wine analyses but used values from other literature sources which raises questions about the validity of the data and whether the sources used provide comparable, reliable data. The authors have established no causal relationship between consumption of wine and the negative health effects they cite."

In the UK, the Wine & Spirit Trade Association said that all wine sold in the UK must comply with European legislation governing ingredients, the wine-making process and UK food safety legislation. While the Food Standard’s Agency said there was no reason for consumers to be concerned.

The report said that manganese, a chemical which accumulates in the brain, is thought to be one of the most harmful of the chemicals detected in the research that was conducted by Kingston University scientists Declan Naughton and Andrea Petroczi. Bernard Weiss, behavioural neurotoxologist at the University of Rochester, New York, also said: “From the point of view of manganese, I would be concerned. Any time you see numbers like they have in this study, you begin to scratch your head and wonder about the effects over a long period of ingestion.”

Vandium, copper and manganese were found to be the most prolific metals in wine. However, zinc, chromium, lead and nickel were also found in the study.

Naughton and Petroczi calculated the levels of metal using data published from scientific journals. The system for calculating the metal was developed by US Environmental Protection Agency which designed a measure of Target Hazard Quotients (THQ) to determine the safe levels of frequent exposure to chemicals.

The report stated that ypically a wine will have a rating of 50 to 200 THQs per glass, but occasionally this can be as high as 300. It also stated that a THQ over 1 is considered to be a health risk.

Possible sources of the metal contamination were thought to be the soil itself, fungicides and fermenting yeasts.

Jane Parkinson 06/11/08