Imported Tuna in the USA often has excessively high levels of mercury, according to analysis carried out on behalf of Defenders of Wildlife, an environmental group. Cans of tuna imported from Ecuador and Mexico were found to have mercury levels much higher than limits set by the federal government.

About 50% of all tuna consumed in the USA is imported.

Defenders of Wildlife, which defends the practice of tuna fishing without harming dolphins, says countries such as Mexico and Ecuador tend to catch larger more mature fish. These larger animals have higher levels of mercury in them.

The group commissioned New Age/Landmark laboratory, Benton Harbor, Michigan, to test mercury levels in tuna samples from the USA, Costa Rica, Thailand, Malaysia, Philippines and Mexico.

Here are some of the lab results:

— On average, tuna from the USA had lower mercury levels than imported tuna.
— Asian tuna had the lowest levels of mercury
— Latin American tuna has the highest levels of mercury
— High levels of mercury were found in cans of ?light tuna’. This is a term used by the FDA for low mercury tuna.

The group says that according to its findings tuna consumption should be reduced to one serving per week. It added that Latin American canned tuna should be avoided.

Defender of Wildlife urges the FDA to monitor the so-called ?light tuna’ more carefully.

The federal government sets the mercury limit on tuna at 1 part per million (ppm).

Of 164 cans tested, the labs found:

— 1 sample – Calmex (Mexico), a ?light tuna’ had 1.4ppm
— 1 sample – Sardinar (Costa Rica), a ?light tuna’ had 1.3ppm
— 4 samples – Tuna Real Solid Pack, 1.5ppm

Toxic mercury levels in humans can lead to serious learning disabilities, developmental problems in children, plus kidney, heart and neurological problems for all age groups. Most governments in the European Union, Japan, USA and Canada advise pregnant and nursing mothers to avoid fish that may have high mercury levels, such as tuna, swordfish, tilefish, some seafoods and king mackerel. The mercury originates mainly from man-made pollution which finds its way into the sea. Some types of fish accumulate the mercury, methylmercury, more than others.

Tuna is consumed more than any other fish in the USA. Most mercury present in American people comes from tuna consumption.

Some useful links:

Is your tuna family safe?

Download the full report (PDF)

Download the summary report (PDF)

The Risk of Following Government Recommendations in the FDA/EPA Joint Advisory on Tuna Consumption

A Link Between Dolphins, Fishing Practices and Mercury Concentrations in Tuna

Five simple things you can do to protect your family

Tuna – Frequently Asked Questions

Written by: Christian Nordqvist
Editor: Medical News Today