Mercury Concentrations in Fresh and Canned Tuna: A Review

Although highly nutritious, consumption of tuna can have adverse health effects due to high concentrations of mercury in their tissues. Low to very high concentrations, exceeding the recommended limits of mercury, have been found in both fresh and canned tuna samples around the world. However, there is inconsistent recommendations by different advisory agencies regarding safe limits of mercury exposure. Recent research has shown that even the "reference dose" recommended by the Environmental Protection Agency is not safe for developing fetuses. Therefore, further testing and stricter advice on tuna consumption should be recommended to protect the public from harmful effects of mercury. Furthermore, the variations in mercury levels in a tuna species from different localities suggest the need for a long-term monitoring program to provide region-specific information on contaminant levels to the public to enable them to make decisions about which fish to eat to avoid the health risk.