(Vegetarians need not respond)
OK, I heard someone talking about having read a “fish advisory” list somewhere, in which it told how often various fishes could be eaten based on mercury content.
I’ve had a little trouble finding this info on either the EPA or FDA website. Sure, I can find all sorts of mercury/fish statements, but no real “list” showing a fish with its maximum safe frequency of consumption.
Has anyone else seen such a list recently???
I came across several such lists but I don’t know if I would call it recently…it was when my wife was pregnant with our son who is 3 and a half now.
What about this? A list of fish species with average mercury measurements:
I was reading an aquaculture magazine today and there were a bunch of back-and-forth articles arguing about some bad science that appeared to show high levels of PCB’s in farmed salmon. The end result was that the EPA or FDA (I forget which one) has not changed it’s recomendation of eating fish (salmon at least) not more than twice a week. That might be wrong, but they should be considering all contaminants in fish, so mercury ought to be includd in that recomendation. You’ll have to search for more precise info if you need it.
But mercury is a heavy metal. Don’t heavy metals accumulate in the body? That would make it seem like there’s not a maximum safe rate of consumption, but rather a maximum total amount, over a period of many years.
It probably also depends on where the fish are from, for that matter. Farmed catfish are probably healthier than wild, and I wouldn’t trust anything from the Great Lakes, even if it’s a species that’s safe elsewhere.
There was a table in Reader’s Digest, admittedly not the place I’d choose to go for my news, a few months ago. I only bring it up because it was careful to differentiate between perfectly safe fish, fish you should be cautious of, and fish sensitive populations like pregnant women should watch out for. I can’t find the issue off-hand, but it should’t be difficult to find.
In my state, fish consumption advisories are issued by the Fish and Boat Commission for individual game fish species based on the water body they are from. Your state may have a similar list.
Consumption advisories for commercially caught fish are more difficult to formulate, as there are many sources of fish, not all of which are equally susceptible to pollution.
As a very general rule, large oceanic predator fish such as shark, tuna, king mackerel, and swordfish have higher than average concentrations of heavy metals due to the effects of bioaccumulation.
Unfortunately, many (most?) farm-raised fish eat commercial fish feed pellets that contain fish meal harvested from ocean fish such as menhaden. These feeds may be high in heavy metals, so you are not necessarily safer eating farm raised fish, either.
FDA/EPA et al. have set “safe” consumption/exposure levels for a variety of contaminants, but they are constantly being revised as new studies are conducted.
Your best bet as a consumer is to properly clean and cook all fish you eat to reduce the amount of contaminants you are exposed to. This includes removing the skin and fatty “dark meat” prior to cooking and using a drip trough cooking method such as grilling or broiling on a rack. IMHO, children and women of reproductive age should limit their consumption of fish to two servings per week or less, unless the fish in question is known to be relatively free of contaminants.
Thanks for sharing this excellent point. Perhaps the feed fish do not bioaccumulate the same amount of mercury as sushi grade tuna, but there is still a component of it in farm fish as well.
First of all, remember that ALL critters have some “contamination” - including human beings. Things like mercury have always been present in the environment to some degree (which is not an excuse for increasing the quantity either locally or globally).
As a general rule, the lower you eat on the food chain, the less problem you have. So small, young, vegetarian fish are safer than big, old, predatory fish. Strictly from a contamination viewpoint, krill-eating whale is probably safer to eat than large tuna, although a decades-old blue whale or humpback probably has significant levels of Bad Things in its body. In general, the less fatty/oily a fish, the better off you are. Bottom feeders and garbage eaters such as catfish are a problem, which is why most catfish these days is farmed catfish and probably healthier than, say, the catfish folks used to eat out of the lower Mississippi. ( :eek: ewwwwwww…)
What the fish is swimming in makes a difference, too - don’t fish immediately downstream of a chemical refinery, as a general rule. But even open-ocean fish thousands of miles from human activity can have significant levels of Bad Things, particulary the large predators such as (previously mentioned) tuna, swordfish, shark, and so forth.
Here in the US the states usually issue information through the Department of Natural Resources or whoever handles hunting and fishing regulations. They’ll tell you what body of water is producing what level of Bad Things in what fish. The Feds presumably issue similar information on ocean fish
To be safest (which is still not completely safe), eat low on the food chain and no more than twice a week for fish. Possibly less if your a pregnant woman or planning to have kids int he near future. Or do the research and find out what fish you can eat more frequently.
And try not to obsess about these things. Stress is bad for you, too.
The mercury in fish occurs naturally and is not a reflection of the the enviroment going to heck…even though other things are driving it that way.
Yes, mercury will never leave your body, so you shouldn’t eat things like tuna at an excessive rate. Over a lifetime, the mercury will build up.
You are almost best advised in all situation to eat 2-3 servings of fish per week, making sure that you continue to eat different types of fish. Fish from different waters, shellfish, white fish, tuna…northern …southern, etc.
Well, Earl, you probably don’t need to worry too much. The big issue for fish is mercury. Mercury is most dangerous to developing fetuses and children, so the people who need to be most concerned are children and women who are pregnant, nursing, or going to be in the future.
Assuming purely from your name you’re not one of those, the levels of mercury in fish aren’t enough to be a major concern. PCBs are a similar situation – probably not enough to worry a healthy adult, but a concern for little people that are still developing.
This assumes you’re not eating fish from a particularly contaminated area – the waste lagoon at the factory, or the river downstream from the Superfund site, or what have you. But most of these places have been found and identified, so you’d probably have to ignore some scary warning signs to catch fish from one of these places.
Now if your working on a Snake-Hips Junior, then the official source is http://www.epa.gov/waterscience/fish/advisory.html
Some environmental groups think these advisories could be stricter, particularly for canned tuna, but it gives you a good place to start.
I eat two cans of tuna (in water) everyday at lunch. It’s a great source of fat-free protein.
So w/ a mean mercury content of of .17 ppm, it works out to about 0.0005 oz per year, or about 14 mg per year. Is this too much?
There seems to be a lot of debate over this. I saw one article that said just two cans a week would give a 132-lb FOUR times the recommended maximum of mercury. (mercury) This totally freaked me out as I am coincidentally a 132-lb woman who eats EIGHT cans of tuna a week.
Yet, immediately after this study, another study was released that said the type of mercury in tuna is not the type that causes toxicity: article. So I don’t know what to do either. I finally broke down and started eating tuna for a little protein after years of vegetarianism and all this comes out. Maybe I’ll just stop eating all together. 
I am a tuna nut because it’s is a great protein source (and convenient) at low cal intake. My research advised a two can limit per week in mothers/mothers to be, and make twice that in others.
If you want a quick, convenient can-o-protein at lunch, and you’re nervous about tuna, there’s always cans of chicken or turkey. Nutritionally, they’re pretty similar to tuna, and they’re less likely to contain nasty levels of mercury.
Although chicken and turkey contain things like antibiotics and God knows what else in in their feed…
Which is why I go by the rule of eating a wide variety of things and not getting stressed by this. Our food has always been contaminated either with stuff from outside (there are areas with naturally high amounts of heavy metals and other toxins in the soil, which are absorbed by plants and animals), natural toxins in the food (aflatoxin in peanuts, solamine in potatoes, tomatoes, and bell peppers, etc.), or spoilage. Our bodies have a evolved to deal with a certain level of this sort of thing, if they hadn’t we wouldn’t be here.
So - avoid the BIG problems (as mentioned, don’t fish in the run-off of a factory), eat a variety of stuff, and buckle your seat belt when you’re in a car - because the average American is far more likely to die on the highway than because of what they eat.
The EPA link that Quercus cited seems to suggest that it’s OK for pregnant women to eat shellfish. Just to clariify- does that mean that shrimp and lobster don’t contain these types or levels of mercury that are dangerous to developing fetuses?
And the designation of shellfish seems a bit broad to me. Clams, quahogs, mussels, etc. are all essentially filters, right? So why wouldn’t they be considered dangerous?
Most specifically, since shrimp are something we tend to eat alot of in my house, is eating shrimp once a week actually OK for pregnant women, as the EPA seems to claim?
Just looking for informed opinion, I guess- we’re gonna have to verify with the OB anyhow.
Thanks in advance,
-j
Not so. While there might be naturally occuring traces of mercury, it’s mostly from human sources – primarily coal-burning power plants, and also from burning waste that contains mercury, and some other sources.
Shellfish are filter feeders/scavengers, so they get some exposure. However they’re still very low on the food chain compared to a top predator like a tuna. Since mercury never leaves the food chain, the tuna gets the mercury from all the fish that ate all the fish that ate a whole bunch of shrimp. So the concentrations in tuna are much higher than shrimp.
One of the biggest mercury sources is indeed cremation of people with ‘silver’ fillings. There is supposedly some new EU regulation to limit the mercury emissions. There might be other ways though, such as freeze-drying the body and separating the heavy metals (cite)