Mercury-laden whale meat may foster heart disease.

Jan 05, 2009

Choi, AL, P Weihe, E Budtz-Jørgensen, PJ Jørgensen, JT Salonen, T-P Tuomainen, K Murata, HP Nielsen, MS Petersen, J Askham and P Grandjean. 2008. Methylmercury exposure and adverse cardiovascular effects in Faroese whalingmen. Environmental Health Perspectives doi:10.1289/ehp.11608.

Synopsis by Carys L. Mitchelmore

Eating mercury contaminated seafood increases the risk of heart disease in men, reports this unique study that examined Faroese whalers.

The risk of heart disease increases in men who eat mercury contaminated seafood -- in this case whale meat. The results support previous findings with other human populations that show higher exposures to methylmercury can promote heart disease.

Methylmercury is an environmental pollutant found in fish and seafood. It is at particularly high levels in some top level predators that eat smaller prey, such as tuna and other large fish and marine mammals. People who eat enough mercury-laden food to increase their body levels may suffer from well known and adverse health effects, including reproductive and neurological problems and an increased risk of death from heart attacks.

This unique study looked at a group of 42 Faroese whalingmen aged 30-70 years old. More than half (26 (or 63% of the men) ate "3 or more whale meals per month." The researchers investigated if long-term exposure to mercury by eating pilot whale meat led to adverse heart related health effects, such as heart attacks.

The men's diets were linked with actual measures of mercury exposure estimated from hair, blood and toenail clipping samples. A variety of cardiac assessments were made, including blood pressure and arterial thickness measurements, both of which are good markers of cardiac health.

The researchers found a clearly significant correlation of increased blood pressure and arterial thickness with higher mercury levels found in their bodies. Mercury levels in toenail samples were the best predictor of the health effect but did not accurately measure long-term exposure to the metal. Concentrations in the men and among the three sample types was highly variable.

The authors conclude that the mthylmercury "from seafood may promote the development of cardiovascular disease."