Angry Toxicologist

National Healthy Moms Health Babies Coalition issued a statement that women who are pregnant (or breastfeeding, or trying to get pregnant, or not trying but might be anyway, or dreaming about being pregnant, or know someone who’s dreaming about…) should eat at least 12 oz of fish per week (all types including the mercury heavy hitters) because of the developmentally helpful Omega-3 fatty acids. This is directly contradicted by the FDA, which says less than 12 oz because of mercury concerns. There’s a fierce fight out there over fish consumption, and a lot of confusion, which is amazingly silly because there is a very simple solution to the tuna or no tuna question:

1) Eat fish low in mercury (Like cod or tilapia).

2) Work to reduce mercury pollution so it doesn’t end up in fish.

Interesting tidbits:

1) Consider the source. Want to know who arrainged the review for HMHB? The fishing industry, of course! Of note, some of the HMHB members must not be happy because there is a disclaimer now on the main HMHB page that says members may not agree with HMHB statements. Not surprising that NIH, CDC, and the American Academy of Pediatrics don’t enjoy being mercury-enablers.

2) Wrong questions and false choices. The reason there is such a fight is that the fishing industry has framed the fight as “Is tuna healthy or not?”. But if you have other fish sources that are low in mercury, the question is moot from an immediate practical public health perspective. As to the industry question, for light tuna, the benefits probably outweigh the risks but only if you’re not eating other fish. Epi studies have shown that simply eating fish confers a benefit, it really doesn’t matter which kind it is. So why not get the benefit without the risk?

3) A study in PNAS (Proceedings of the National Academy of Sciences) came out a couple of days ago that found that changes in mercury loads in the atmosphere would decrease the mercury in the lakes and, therefore, the fish, rather quickly. So, pollution controls would dramatically help the mercury situation and we could all load up on albacore tuna again. The bizarre twist here is that the fishing industry is really the victim of mercury pollution from things like coal. Yet, because of their denialism, they have gone from victim to enabler. Read more about denialism’s deck of cards here.

Comments

#1 Melissa
October 9, 2007

Thank you for pointing out the many sides of this issue (and the biasness in the new study that has come out that the media has blindly taken up).

People should be aware of both the risks and benefits of seafood. The decision of what fish to eat can be a challenge and often contradictory. At the very least, people should know that FDA and EPA have issued advisories about mercury contamination in commonly-sold fish. The problem is, this information is hard to find and is not usually available where it is most necessary: your supermarket.

Oceana, a conservation group, is trying to get major grocery companies to post this government advice at their seafood counters. Thanks, in part to their work, Whole Foods, Safeway stores, and Wild Oats voluntarily agreed to post the FDA�s recommendations and they have had positive responses from customers and no loss in seafood sales. But other companies like Wal-Mart, Costco, and Giant have refused to do so. Oceana has a list of which companies care about their customers� health enough to post this advice, as well as a list of companies that don�t. You can get the Green List and Red List at their website.
#2 Amanda
October 9, 2007

False choices is right, and that’s just what the seafood industry wants. Although I can think of another industry that would benefit from the “Mercury isn’t that bad!” rhetoric.

Melissa, it’s great that those grocery lines have posted the FDA guidelines at their counters! Good work. Too many people think the guidelines say “Don’t eat fish if you’re pregnant,” when of course that’s not what they say at all.
#3 PETER H. FLOURNOY
October 9, 2007

You actually should get your facts straight before you publish material like this. Most fish we eat are high in selenium which has been shown to disable any negative impacts of mercury contained in most fish we eat, including all the tunas. Also, albacore tuna — so called white meat tuna — comes from at least two different sources. About 20-25% is U.S. troll caught albacore which has been tested for the last several years and has never been found to exceed even the strictest mercury advisories — This is younger, smaller fish than the other 70% or so, most of which comes from foreign caught long line albacore which while still safe to eat has been shown to carry higher mercury levels and less omega-3 fatty acids (which are good for everything from brain development, to heart disease, to depression). Long lines, as a gear type often have some interaction with sea turtles. It is for this reason that NRDC, Turtle Island Restoration Network, and other marine mammal concerned organizations are scaring the American public into thinking they will be harmed by mercury in tuna. There has never been a recorded case in the history of the U.S. of a person getting mercury poisoning from fish caught on the high seas as all the tuna are caught.

Going after funding sources is a cheap and shabby way of discrediting otherwise robust science. No ‘fishy money’
backed any of the research. National Fisheries Institute merely paid to help publicize this information, which can scarcely taint the value of the research itself. Indeed, given its public education mandate, NFI would be remiss were it not
to make every effort to publicize this information.
I hope we can all look forward to the recently announced University of Washington studies which will ask many of the same questions about nutrition and child development.

Put another way, should we not believe anything on NPR because it accepts huge grants from the Pew Charitable Trusts?
#4 Mark Powell
October 9, 2007

Thanks for your thoughts, Angry Tox. Peter, maybe you should disclose your role in the fishing industry as you comment on mercury/seafood and the speculative “protection” afforded by selenium. I’ve found Charles Santerre’s good website that offers strong and credible advice, I learned from reading it. You can find it at:
http://fn.cfs.purdue.edu/fish4health/Walletcard/walletcard.htm
#5 apy
October 10, 2007

Peter,
Do you have a reference for the selenium thing I could read? Preferably peer-reviewed paper.
#6 sailor
October 12, 2007

“So why not get the benefit without the risk?”
Because small freshly-caugh tuna tastes so much better than talapia.
Mark, I find your criticism of Peter poorly researched. The site you link to is very simplistic and basic. If you search the internet for the selenium/mercury link you will fnd plenty of interesting information. Peter may or may not have clients in the fishing industry, but in the long run, science is about truth and not politics.
I would say that the jury is still out on whether eating tuna will do you harm. Pregnant mothers of course should avoid eating controversial pescoids. In the meantime I have to get back to my sushi…
#7 sailor
October 12, 2007

Apy, here is a starting point if you can get access to the references listed at the bottom.
http://chetday.com/mercurymineralfish.htm
#8 Cathy W
October 12, 2007

The choice may not be so obvious for low-income women. Let’s take the prices at my local grocery store: Tilapia is about $4.99 a pound (and it’s one of the cheaper types of fish my supermarket carries); a 6-ounce can of “chunk light tuna in water” is about $0.90. I can pay $3.75 for my twelve ounces of tilapia, or I can pay $1.80 for twelve ounces of tuna. There exist women for whom $1.95 a week might make the difference in choosing tuna over tilapia, or if the message has gotten through that tuna is unsafe, between not eating fish and eating the recommended amount.
#9 Mike Huben
October 14, 2007

Flournoy wrote: “selenium which has been shown to disable any negative impacts of mercury”. ANY negative impacts? A lawyer is telling us this? 5 minutes of web search with selenium and mercury found two references that give us plenty of reasons to doubt.

MERCURY AND SELENIUM POISONING: WHEN 1+1 does not equal 2
This release points out that by some measures their effects seem to cancel out, but by other measures their effects seem magnified.

Ecological aspects of mercury–selenium interactions in the marine environment.
“On the other hand, the increased retention of mercury caused by selenium may lead to a higher level of biomagnification in the food chain and a higher burden in the individual. This might counteract the positive effect of decreased intoxication.”

What I find striking, as I search, is that there is essentially no reference to alternative vegetable sources for omega 3 fatty acids. Since the alleged cardiovascular benefits of fish come from those fatty acids, flax oil could substitute for fish rather easily.

And if selenium is such a magical cure-all, I’m surprised that we don’t see the aquaculture industry supplementing fish feed with selenium to articially raise the levels and advertising this. I suspect that nobody knows what an “optimum” balance is, what the tradeoffs are, and any mention of selenium is based on wishful thinking rather than actual knowledge.