Dear Watchers

Fisher/Seafood Processor/Mother Responds to Mercury Article

Dear Watchers:

As a fisherman, seafood processor, and a mother concerned about health issues, I feel the need to comment on the very compelling article Al Hanners and Tom Pratum wrote on the presence of mercury in our environment and the danger it poses in our food supply (“Mercury Rising,” Whatcom Watch, Oct. 2003). Editor’s note: The article was written by Al Hanners. Tom Pratum wrote the sidebar.

Mercury does not stay “in our tissues for the rest of our lives.” The article perpetuates the misunderstanding that “once mercury enters our tissues, it stays there for the rest of our lives” (quote “Mercury Rising”). Fortunately this does not seem to be the case. Dr. Jane Hightower, whose research largely stimulated the recent mercury concerns, found that with diet modification her study patients who were experiencing both high levels of blood mercury and symptoms of mercury poisoning were generally able to relieve symptoms and return their blood mercury levels to normal. (Hightower J. “Mercury Levels in High-End Consumers of Fish,” Environmental Health Perspectives, Nov. 2002.) See more at “New Study Finds Upper-Income Fish Eaters Exposed to Dangerous Levels of Mercury.”

As discussed in “Mercury Rising,” mercury is ingested in many forms, with greatly varied toxicities. The rates at which they are absorbed and retained also appear to vary greatly, both among individuals and communities, indicating that other factors, possibly dietary balance, play a critical role. (Question: why aren’t the Japanese, each consuming an average of more than 100 pounds of fish a year, all brain-dead?)

The new (2002-2003) data upon which the FDA and EPA based recent tuna consumption recommendations is not as informative as it needs to be to eliminate confusion. All “albacore/white tuna” sizes and ages were studied as if they belonged in one category, but they do not.

All “albacore/white tunas” are not the same, and mercury content differs.

Local fishermen who troll for the younger, smaller albacore wish strongly that studies and subsequent discussions about “albacore” would discriminate between our troll-caught albacore and the huge, older albacore caught by foreign longliners. Differences are so significant that the sizes and ages need to be considered and put into different categories for study. It is possible that even the area of the ocean in which the albacore are caught needs to be considered.

Very large albacore (60–90+ lbs) live deeper in the water and are caught by longlines drifting in the water or as a bycatch of seining for yellowfin tuna. These larger fish have higher levels of mercury because they have had a longer time to accumulate it. Troll-caught albacore are younger, smaller fish, living near the surface of the water. They usually weigh about 9–18 lbs. They are caught in an extremely targeted fishery (no bycatch) by boats pulling barbless hooks. As they are younger, they have much less mercury in them.

The big canners (BumbleBee, StarKist, Chicken of the Sea) used to buy smaller albacore for their albacore/white tuna pack. Then the industry changed. Several years ago the big canners began using the larger longlined tuna for the albacore/white tuna, therefore the mercury numbers are higher now. About the time the big canners switched to the bigger fish, the FDA ceased monitoring mercury content in their canned tuna.

Only albacore from the big canners (the larger albacore) were tested by the FDA for the recent (2002–2003) study. I know of no smaller canners or coastal fishermen being asked to contribute samples of troll-caught albacore to be studied, and I know for sure that Pelican Packers wasn’t asked to contribute fish.

As a result of the confusion caused by the incomplete FDA data, separate testing of coastal troll-caught albacore is being conducted. I recently heard that Dr. Michael Morrissey of the Oregon State University Seafood Research Laboratory has just begun one of those studies and results should be available within a few weeks.

Under the “What we can do” section of “Mercury Rising,” I would like to add a key piece of information. Various nuts are indeed high in Omega-3 fatty acids, but only in short chain Omega-3s. The health benefits of Omega-3 fatty acids are principally from the long chain Omega-3s, and only seafood contains useful amounts of these. Our bodies may be able to assemble these longer molecules, but there is disagreement about efficiency and even if it actually occurs.

An excellent source of research is the online newsletter, http://www.fatsoflife.com. The June issue specifically deals with different effects of plant- and fish-sourced Omega-3s, see also the Harvard Health Letter, Jan. 1, 2003, which states; “Fish is a special food because it contains two important varieties of long chain omega-3 fats that you won’t find anywhere else in a conventional diet.”

Smaller albacore have some of the highest amounts of healthful long chain Omega-3 fatty acids available from any food source.

We must weigh the health benefits of fish consumption in making our decisions. Even mercury crusader Dr. Hightower said in Elle Magazine: “Don’t be afraid—in the big scheme, bingeing on sushi or eating swordfish all week on vacation won’t hurt you.”

The points I hope you have taken away with you are these: in time mercury flushes from our bodies, all tunas are not the same, new FDA mercury data is insufficient, seafood has many nutritional benefits, and even Dr. Hightower approves of consumption of seafood.

Read labels, ask questions and care about what you eat.

Author Replies

I thank Judy Cosky for her response to the article on mercury that was published in the October 2003 Whatcom Watch. Her well researched, informative, and nicely balanced comments seem to reflect her roles as a fisher and a mother.

As a scientist most of my adult life, I have come to value peer reviews that make science reliable, and hence, useful. As an environmentalist and grandfather, I have come to believe that people are an important part of an ecosystem.

Judy Cosky pointed out that rates at which mercury is absorbed and retained may vary greatly among individuals and communities, indicating that other factors, possibly dietary balances, play a critical role. (Question: Why aren’t the Japanese, each consuming an average of more than 100 pounds of fish a year, all brain-dead?)

Doubtless, nobody has answered with certainty, but for starters, what kind of fish do Japanese eat, mostly albacore tuna caught by long-liners and high in mercury, and farmed salmon fed bottom fish high in PCB’s? Or do Japanese eat mostly other fish like many knowledgeable Americans? Surely Japanese know the risk of eating too much fish containing considerable mercury. It was an epidemic of brain damaged and some dead residents of a Japanese fishing village that led to the understanding that mercury can be dangerous to people’s health.

The Japanese living in Japan are very unusual people with regard to diet and health as related in “8 Preposterous Propositions” by Robert Ehrlich. Japanese have among the lowest incidence of coronary heart disease of the planet. Among 22 countries, Japan has the lowest consumption per capita of calories from fat; United States has the highest consumption per capita of calories from fat and the highest incidence of heart disease. Japanese-Americans, adjusted to American way of life, have a three- to five-fold risk of coronary heart disease as Japanese living in Japan.

There is another Japanese paradox. In spite of their remarkably low incidence of coronary heart disease, Japanese who died in Japan had the same degree of sclerosis of aortas as Americans but were even more sclerotic than Americans in their brain arteries.

Would it be prudent to plan our mercury consumptions according to an American lifestyle?

The foregoing was written before 1/15/04, when a Bellingham Herald article stated that Puget Sound wild Chinook salmon are more contaminated by PCB’s and dioxins than farmed salmon. English sole and rockfish are even more contaminated than salmon.

“A leading northwest tribal fisheries official said the report on PCB levels in sound Chinook may spur a new look at salmon–heavy Native American diets.”

Wouldn’t it be prudent to request your grocer to clearly label all fish from Puget Sound with both the name of the fish and the source? Then you could make an informed decision on what you want to eat.