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Mercury still an issue in canned tuna

To be environmentally responsible and health conscious, eat albacore tuna from the West Coast fishery.

To be environmentally responsible and health conscious, eat albacore tuna from the West Coast fishery. In other words, once again, local is best.

This was not the case for the people of Minimata, Japan, in the 1950s and ’60s, when a major chemical company dumped highly toxic methylmercury into coastal waters.

As of March 2001, 2,265 victims had been officially recognized (1,784 already dead) and more than 10,000 had received financial compensation.

Lawsuits and compensation claims continue to this day and Minimata Mad Hatter’s Disease (from the mercury poisoning experienced by hat-makers of previous centuries) remains an important issue in Japan.

Ontario Minamata disease in the 1960s from a chemical and pulp mill in Dryden, Ont., severely affected the Grassy Narrows and Whitedog First Nations, where fish were the main food source and commercial fishing, and related tourism businesses, were their main livelihood.

A report published in Japanese in the Journal of Minamata Studies in 2011 showed that these people are still suffering the effects.

Mercury content in canned tuna can vary widely, which is probably why the American Medical Association adopted a policy that doctors should warn pregnant women of the potential danger.

The mineral toxins ingested by smaller creatures concentrate in the bodies of the big fish at the top of the food chain. The answer to pollution is not dilution.

Tuna fishing environmental damage comes from two activities: overfishing and bycatch of other species.

The practice of spotting dolphins feeding then netting indiscriminately, dumping the drowned dolphins, led to ecolabeling. However, “dolphin-friendly” refers only to claims that feeding dolphin pods were not specifically targeted and does not mean that dolphins are no longer caught in nets and drowned.

According to the World Wildlife Fund, United Nations fishing agreements are ineffectual.

The number of fishing vessels keeps increasing while the tuna populations remain stable or decreasing. Skipjack tuna, representing 90 per cent of the canned market, are considered potentially vulnerable. The world’s tuna fisheries face ecological disaster.

The overfishing of bluefin tuna is now widely known.

Selfish contrarians contribute to the extinction of the wild bluefin now that their species is nearing extinction. And bluefin cannot reproduce in netpen conditions.

On a happier note, the West Coast tuna fishery targets albacore tuna, a species with a high reproductive rate, so tuna caught by local fishers are not endangered at this time.

You can buy canned albacore tuna locally caught, either from the fishers themselves or from St. Jean’s Cannery in Nanaimo.

The taste difference from cheap cans of unknown provenance is unmistakeable.

If you want to check the ethics of seafood, browse for blueocean.org and search the status of each species. And why wouldn’t we want to contribute to ecological balance rather than mindless destruction?

Marjorie Stewart is board chairwoman of the Nanaimo Foodshare Society. She can be reached at marjorieandalstewart@shaw.ca.