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How often to eat fish with all the pollutants?

Caroline posted a good post in the thread I initiated called "organic produce: a beautiful lie"

Caroline wrote "Many pesticides (and DDT is only one of them) are extremely long lasting, and once introduced into the ecosystem they are damned near self perpetuating. Seafood is a good expample of the problem. The food chain in the ocean is that fish are ever eaten by bigger fish, and the farther up the food chain you go, the more concentrated the pollutants (mercury, etc.) are in the fish we catch and eat. Top-of-the-food-chain fish such as swordfish, tuna, salmon, well, all of the "big guys" are hazardous when eaten more often than once every week or two. And sometimes maybe even when eaten that little. I don't know of any fisherman or agency who will divulge that information completely. "

Caroline's post got lost in the thick of the organic produce thread, and I thought the topic on fish deserved a separate thread. I've heard all the benefits of fish, particularly salmon and better yet wild salmon. Yet, I've been worried for years about mercury. How dangerous is mercury anyways? I've been trying to eat more fish, but now I'm full of doubt, thanks Caroline, j/k. :)

Can someone help me out and confirm or mitigate my fears about fish?

edit: I found out selenium can help against mercury, not sure about the other toxins though.

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  1. Here's a site which will give you some info on sustainable fish: http://www.montereybayaquarium.org/cr...

    Under Che Tools, click on buyer's guide at the bottom of the page and it will give you an extensive list of fish to eat & avoid

    1 Reply
    1. re: Cherylptw

      I followed your instructions and got the results you implied. In the buyer's guide, I see a lot of tuna. I'm surprised there is so many variants of tuna. Just when I thought I figured out one tiny puzzle, I find the puzzle is o so much more complicated. Such is a life long learner's task.

    2. Unless you are extremely old or young, or pregnant, I wouldn't worry about the mercury content of seafood unless you were eating copious amounts of the stuff per day -- e.g. something ridiculous like 5% of your body weight.

      And if you eat the typical 6-8 ounces of fish, 3-4 times a week, the benefits outweigh the risks associated with the ingested mercury.

      But read more about it here: http://www.fda.gov/food/foodsafety/pr... and decide for yourself.

      5 Replies
      1. re: ipsedixit

        A co-worker of mine WAS eating solid white tuna and an orange every single day at work a while back...I pointed out a few articles to her and she's changed her ways and has thanked me...said her doctor also thought it would be good to NOT eat it every single work day. sheeesh...I totally don't get it how people can eat the same exact thing every single day and not suffer from food boredom, ya know?? I'd go out of my mind.

        1. re: Val

          Do you have any idea where your friend decided this diet was a good idea? I ask because I had a coworker who was on the same diet- canned white tuna and orange juice every single day at work, possibly twice a day. Needless to say I was not a fan because he'd have his first portion at 10am and stink up the kitchen area for the rest of the day. He suffered from severe mood swings and I can't help but wonder if that had something to do with the mercury in the tuna.

          1. re: queencru

            Queencru, I have no idea where she got the idea of tuna and oranges...truly...I wondered too but did not ask...I just felt she should know about solid white albacore tuna and the risk of eating it 5 days a week!!!!

          2. re: Val

            I read about a woman who loved tuna and ate it every day. She developed an allergy to it.

          3. My husband is a fisherman ( and I come from a long line of fishermen) and we eat fish at least twice a week, sometimes 3 times depending on his catch. We had a scientist in Bermuda talking mercury content in fish, but what he also said was it is an organic form, most fish are born with it and you can eat swordfish everyday for your entire life and never have enough mercury content to harm you. I personally would be more worried about the pesticides on fruit and vegetables, that’s if you do not by organic.

            Thank you ipsedixit, and I totally agree the benefits outweigh the risks associated with the ingested mercury!

            There are two fish called white tuna

            Albacore tuna, - the pale-fleshed tuna favored by the canning industry, also known as shiro maguro, bin-naga maguro, or bincho maguro

            Escolar, - which is a snake mackerel, not a tuna, eating too much will have a laxative effect.

            1. Bottomless,

              Mercury obviously is not a good thing. In fact, it is very toxic. However, I would say most Americans do not eat enough fish to be concern. That is not to say all Americans should not be concerned. If you only eat fish once a week, then I wouldn't worry, especially if you don't eat the same fish over and over.

              I absolutely agree with your statement about swordfish and shark. I won't worry as much for tuna and salmon. Another thing I like to point out is the health benefits (therefore tradeoff) of salmon. Salmon on average has a very high level of omega-3 fatty acid, about 5-10 times of many other fishes like catfish, mahi mahi, and cod. In effect, you can eat salmon in 1/5th or 1/10th portion of other fishes and and get the same amount of omega-3.

              In addition, most of the recent posters and articles I read put salmon low on the mercury level, unlike swordfish and shark.


              For disclosure, I don't work in the salmon industry. :) Just so you know.

              1. I can only contribute that when I was a wee girl living on the naval air station in Millington Tennessee, the CO had the base sprayed nightly in the summer by trucks that poured out huge clouds of fog as they drove through the base. We used to run in the fog behind the truck until our parents caught us but I had several trips under my belt by that time. That's a lot more exposure than you get from eating contaminated fish, but so far I've lived to tell the tale. That's all I got.

                1. Forgot to say- the truck was fogging

                  1 Reply
                  1. re: EWSflash

                    Yeah, I read about those stories. It is very common in those days.

                  2. There are several types of mercury. They include metallic mercury, and both inorganic and organic mercury compounds.

                    The Mercury found in fish is an organic form; it is not the metallic mercury

                    6 Replies
                    1. re: bermudagourmetgoddess

                      Sorry bermuda, but in this case organic does not mean healthy. Just the opposite. When one talks about organic mercury it's a scientific term, not a marketing term as is "organic chicken". The organic form of mercury is especially toxic because it is more easily absorbed into your body than inorganic mercury. And mercury stays in the body. That's why it accumulates in fish that are high in the food chain (salmon, swordfish, tuna and such, rather than the anchovies and sardines they eat). And to say fish are "born with it", if true, is just to say they are born contaminated with it. That said, I'm not a purist. I eat salmon a few times a month, and tuna occasionally (not for health reasons -- I just am not that fond of it and it's pretty expensive). But let's not twist the facts.

                      1. re: bermudagourmetgoddess


                        Your point? Organic forms of mercury are toxic (I am agreeing with Zeldog). Organic mercury actually can be more toxic than other forms due to the higher lipophilic (hydropholic) property, which allows greater PO bioavaliability and greater blood-brain barrier penetration. In short, a person can absorb organic mercury into his/her body better and they go into brain faster. Let me quote emedicine:

                        "Organic mercury can be found in 3 forms, aryl and short- and long-chain alkyl compounds. Organic mercurials are absorbed more completely from the GI tract than inorganic salts are; this is because of intrinsic properties, such as lipid solubility and mild corrosiveness (although much less corrosive than inorganic mercury)...."

                        The elemental mercury (metallic mercury) is actually much safer from the ingestion route (not from the inhalation angle). Only 0.01% is absorbed through the GI tract. Here are two cases for oral ingest of elemental mercury.


                        *He drank 3 kg of elemental mercury.*

                        I am definitely not against people from eating fish. In fact, I encourage fish consumption as my other posts suggsted. However, that does not mean organic forms of mercury are safe.

                        1. re: Chemicalkinetics

                          My Point is....I am not saying mercury is good for you, but it is not only in fish (sword, tuna, and others...). Everything can be bad for you, that is why if you enjoy swordfish or Tuna, eat it in moderation...

                          Lets not forget the nasty growth hormones fed to livestock to either speed the growth or produce more eggs and milk. Or the wonderful pesticides they spray all over vegetable and fruit crops...But I guess that is another post...

                          Plants absorb mercury from the soil and air during normal growth. In some cases, plants concentrate mercury to small metal droplets. Some bacteria convert inorganic mercury to organic mercury compounds. Fish and animals may consume mercury containing bacteria. Some animals and vegetables convert organic mercury back to inorganic compounds.

                          This constant cycling of mercury from one form to another has gone on for eons without any recognizable toxic effect on the world's food supply. Our use of mercury has probably not significantly increased the mercury concentration in the oceans.

                          Mercury does not seem to be a threat to the U.S. food supply based on all available data. Much of the bad publicity on mercury emerged from the misuse of mercury-treated materials. The biggest problem was uncontrolled dumping of industrial waste into the environment.

                          High levels of mercury naturally occur in some freshwater lakes, rivers, creeks and reservoirs in California. Fish in these waters may contain high mercury levels. The California Office of Environmental Health Hazard Assessment annually issues fish consumption advisories on possible contaminants in sport fish. The latest consumption advisories are in the California Sport Fishing Regulations (available in sporting goods stores).

                          1. re: bermudagourmetgoddess

                            I don't disagree with many things you said and I agree some of the mercury concerns are slightly overblown, especially for salmon. That being said, it is very difficult to get your point from the previous message at May 12, 2010 11:22AM . Is it? That statement comes across as if organic mercury is not dangerous.

                            Yes, many other organisms have mercury in them, us included, but that does not mean everything is the same. Some have much higher mercury levels than others, by a lot. Quantity matters. It is one thing to drink 1 cup of coffee a day. It is another thing to drink 100 cups of coffee in a day.

                            Swordfish and shark have an average Hg level of ~1 ppm, while salmon and cod are at ~0.01 ppm. A 100 fold makes a difference.


                          2. re: Chemicalkinetics

                            So you are saying I should probably avoid the organic forms of ricin from castor beans, strychnine from trees, and naturally occurring arsenic, too? ;-)

                        2. I love most all seafood, and I mostly eat salmon and tilapia. I am glad to hear that the general consensus is that it is safe. I eat these types of fist a lot, but I was tempted to buy some swordfish steaks at the grocery store the other day.

                          2 Replies
                          1. re: amylovescupcakes

                            :) Safe for you, Mr. Salmon Eater. What about all the poor Swordfish and Shark eaters? Have you thought about them?

                            1. re: Chemicalkinetics

                              Ha ha :) I have, because I wanted to cook swordfish the other night!!! However, I was on the phone with my dad and he said the very same thing as the first post-that bigger fish contain higher levels of pollutants. So...in addition to the price, I decided to forego it for now...

                          2. Mercury in fish is indeed a real danger. I would not discount it. PCBs are also another factor to consider. The smaller the fish, the less your risk. Large fish like tuna, swordfish, even striped bass can contain significant quantities of pollutants. The factor is how big are you? How large is your portion of fish? Was that portion taken from a very large fish, or a smaller one? You may not know the answer to that unless you caught it yourself. How often are you eating fish and what kind?

                            There is no clear-cut defining answer for you, because there are many factors to consider. I think it was last week that Richard Gelfond (Imax CEO) who was diagnosed with mercury toxicity, decided to donate $1 million to Stony Brook University for seafood study. It's a very real issue, and you are right to be concerned. Keep researching your questions until you have answers you are confortable with, and if you're making decisions for children and their fish intake, be even more cautious.

                            1. you know what else is a real danger? All the crap they give chickens and beef to bulk them up, don't forget the drugs the give cows to produce more milk. How about the chemicals they use on veggies and fruits to produce more food and or keep he bugs away?

                              Eating too much fatty foods can also lead to blockage of the arteries and or a stroke or heart attack

                              So Support a swordfish fisherman (my husband and mom) and buy fresh swordfish and enjoy and as everything ...eat it in moderation

                              1. Oh my goodness. In addition to the thread on dairy, I am depressed thinking that everything I eat is going to somehow kill me :) Okay, not seriously, but really, when you think about how many things we do eat that are not good for us, it is kind of sad. Is there ANYTHING that won't give us cancer or heart disease??? I think the common rule must be what many of you have said. Everything in moderation...

                                7 Replies
                                1. re: amylovescupcakes

                                  You'll be sad to hear, of course, that the most common carcinogen that you encounter every day is oxygen. Oxygen itself reacts with DNA in ways that can lead to cancer.

                                  The world is a dangerous place...

                                  1. re: amylovescupcakes

                                    <I am depressed thinking that everything I eat is going to somehow kill me>

                                    Not eating anything will kill you quicker. Lemme know if you hear of anyone who's managed to achieve immortality through diet, though.

                                    1. re: small h

                                      Oh trust me, I don't have the "not eating anything" problem :) Sometimes I wish I did!! I am not really depressed (I said after that, Okay, not seriously...) It just seems to me that every time you turn around, there is another new report or study out-that's what I was referencing.

                                      IH, that is interesting...I haven't heard of that.

                                      1. re: amylovescupcakes

                                        <every time you turn around, there is another new report or study out>

                                        I can't remember a time when this wasn't true, so I've gotten used to it. For every actual new and useful piece of information, there are approximately 12 gazillion ridiculous scaremonger - or hopemonger - theories, to keep us amused. Live long enough, and you can watch "margarine is better for you than butter" morph into "margarine will dissolve you from the inside out and steal your 401K." When microwave ovens first appeared on the market, there was a flurry of panic about whether microwaved food would kill you dead, because, you know, microwaves! They're micro! And wavy!

                                          1. re: small h

                                            Microwave would be a bad example. In the case of microwave, it was the experts who were correct that stating it is not a concern. It was the common people who got freak out because microwave radiation sounds dangerous like nuclear radiation or x-ray radiation.

                                            In short, the microwave example would suggest that we should read the new reports.

                                    2. With that oil spill creeping up the coast I'm wondering if I should stock my freezer with seafood today. Anyone else thinking along those lines?

                                      7 Replies
                                      1. re: givemecarbs

                                        For Gulf coast seafood, too late to avoid tasty petroleum-marinated seafood. Though that may push prices up from seafood in other parts of the world...

                                        I despair over the spill in the gulf.

                                        1. re: Indirect Heat

                                          I don't know what distresses me more.

                                          People who only worry about the price of seafood b/c of the spill, or the ecological, economic and environmental effects of the spill.

                                          Maybe it's because we are Chowhounds, but it seems like alot of people are putting the focus on the price (and selection) of seafood over the the more critical effects of the actual oil spill.

                                          I too despair over the spill in the gulf ... for a variety of reasons.

                                          1. re: ipsedixit

                                            All of the above. Oil spills you can see from space are pretty depressing.

                                            1. re: Indirect Heat

                                              Or oil spills so big that the feds are having a hard time even ESTIMATING the size of it.

                                          2. re: Indirect Heat

                                            Not true at all. I am not happy with the spill, but ther are other areas of the Gulf that have not been affected. I caught some speckled trout the other day, and all the comments are about you're going to eat that. There is still plenty of clean water in the Gulf of Mexico. There is no oil at all in Texas or Mexico, plus the southwestern part of Louisiana, where the majority of their catch comes from, is unaffected. There is so much misinformation out there. IT IS NOT TOO LATE TO AVOID TASTY-MARINATED SEAFOOFD. I never use caps. Check your facts.

                                            1. re: James Cristinian

                                              Well, soon or later, the spilled oil will float to Texas and Mexico.

                                              1. re: Chemicalkinetics

                                                Is that what you want? The currents do not suggest that. It all depends on a loop eddy that could bring oil to Texas, or not. I am not going to despair until oil hits land, and if so, it's not like the whole coast will be innundated. The Gulf is enornmous. Down here, we are used to dealing with this, technologhy on oil spills is better than ever, despite the blundering of BP. We have whole industries that are devoted to containment. During World War II, thousands of ships and tankers were sunk in the Gulf and Atlantic. What happened to the oil. Nature is very resilient. We will get through this.

                                        2. Didn't discover this thread until this morning, and what a surprise to find myself referenced! Glad someone listens to me! '-) I then wrote a long comment, which vanished into cyberspace, as many of my best posts do on Chowhound. I suspect there is an incompatibility between my version of Internet Explorer and the Chow website. I TRY to remember to compose my posts in a word processor first, then cut and paste them in. And that's what I'm doing now. I think my frustration has simmered down enough since this morning, so I'll give it another shot.

                                          When it comes to fish, or anything else in the human diet, I apply what I call "Caroline's 1,000 Year Rule." It says that if man has been eating something for a thousand years or more, it's probably safe to consume. BUT... If man has modified it -- changed its diet, changed its habitat, changed the way it progenerates -- then it's up for SERIOUS scrutiny! Example: Beef. Man changed its diet from grass to corn and voila! CHOLESTEROL! (In humans, if not in cows, but I'm pretty sure it's not good for the cows either.) Then man changed the diet of cattle again by thinking about all of those bones that were just thrown away after slaughter when they could be turned into bone meal and fed back to cows! Cows eating cows. Voila! Mad cow disease, aka Creutzfeldt Jakob disease. Without that, we may never have known about prions, and really, would that have been such a bad thing?

                                          So you can see what man's "interference" with things that "nature" has spent thousands to millions of years working out can do? For that reason, I don't eat farm raised fish. At least not knowingly. Who knows how many restaurants claim "wild caught" on their menus because it sells? Fish were meant to swim in oceans, lakes, rivers and streams. God knows we've dirtied all of those up enough, but why would anyone think a fish "farm" is a better environment? My own problems with farm raised fish (with the exception of "fish farms" that raise fish in netted enclosures out in the ocean) is that it is an unnatrual environment and the build up of doctored food fed to the fishes to reduce infections is not a good thing. Why raise them for human consumption in an environment that is so toxic it requires antibiotics to keep them healthy? Money is the answer, but they can do it without MY money...!

                                          Mercury and other heavy metals and/or toxins in wild caught fish are probably not 100% new, though increased levels may well be the result of man's pollution of the globe, including all waters. But again, commons sense can help you out. I have not ate anything caught off the shores of New Orleans since Katrina! The pollution from that total catastrophe will be around for decades and probably centuries. And now with this totally irresponsible oil spill in the Gulf, who knows how far that catastrophic damage will spread? So try to know where your wild caught fish is caught, and just how clean those waters are. And don't eat fish -- or anything else, except water, every day!

                                          When it comes to government warnings about things, I pay attention, then I think about them, analyze them, question them, and also take them with a grain of salt. Remember when the government told us all we had to eat margarine instead of butter? Hey, let's have a big round of applause for hydrongenated and trans fats! Yay government! A little tip here; if you can find grass fed butter, it is as healthy as olive oil! But try finding it. But if the demand becomes high enough, the supply will show up. "Build it and they will come." Build the demand. Demand wild caught fish. Demand pesticide free produce. But don't demand local foods in order to reduce the carbon foot print of foods. The technology is readily available to use sails on cargo ships, so bring me my bananas and mangoes and out of season fruits and veggies on the wings of the wind! And before you start growing your own produce, learn something about the history of the land you'll be growing it in and of the water you'll be using for irrigation! And if you live near places like the Love Canal, for heaven's sake, rush to the supermarket and buy produce from someplace else, even if it's across an ocean or two!

                                          It's dangerous to be hungry in today;s world because you don't always know whether your food is safe. Try to figure it out for yourself. And use my 1,000 year rule. It works! '-).

                                          4 Replies
                                            1. re: Caroline1

                                              Caroline, love the passion and the angst in what you wrote, and cannot agree more, for the most part. Plenty of wisdom to chew on. So thanks especially for taking the time for this second writeup.

                                              However, my skepticism tells me it will be a while before we see designations such as "shipped by wind-powered means" on our produce, although it would be a nice option I will gladly support. That would solve the agony of conflict between eating local and eating quality food that often has to be imported. I would always stand by trying to eat with the seasons, though, even if only for paying tribute to what our ancestors used to do.

                                              1. re: tarteaucitron

                                                I'm glad to say there is a LOT of experimentation and research g oing on with wind powered shipping, from using a kite to pull a vessel (cuts down on how much a crew has to trim the sails, thereby reducing manpower demands) to reviving the old square riggers, and even some new square metal sails that are computer driven to catch the wind. But we aint there yet. FORTUNATELY, this is one area where corporate greed will work on the consumers' -- AND the planet's -- side. It radically cuts fuel and maintenance costs.

                                                The interesting thing about "what's in season" is where you're from. I have a couple of friends from Chile, who cannot adjust to snow at Christmas! It's all in where you're raised and what you're used to. '-)

                                                Oh, and for general information about fish, be aware that in the U.S., the law says a fish vendor MUST show you the paper that states where (in which waters) the fish was caught IF YOU ASK. So ask already.