How Fish Farms Destroy the Ecosystem and Threaten Your Health

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May 24, 2016 | 307,359 views

Story at-a-glance

  • Fish farming is one of the least sustainable approaches to farming. It also causes many environmental problems, and poses unique risks to your health
  • Land-based fish farms have been shown to produce significant ecological changes downstream, reducing biodiversity and killing pollution-sensitive species
  • Farm-raised fish develop all sorts of mutations and deformities, including deformed ear bones, which reduces their hearing. Farmed fish also tend to contain greater amounts of toxins than wild fish

By Dr. Mercola

Fish used to be one of the healthiest foods on the planet, but pollution and farming perversions have made most fish a highly unhealthy food, and some types of farmed fish the most toxic food on the planet.

Fish farming, which began about 65 years ago, is considered by many to be one of the least sustainable approaches to farming. This is particularly true when it comes to carnivorous fish like salmon, which feed on other fish. To raise 1 pound of salmon, you need over 2 pounds of wild fish to produce its feed.

In addition to being an unsustainable practice, aquaculture also causes many environmental problems, and poses unique risks to your health. In fact, industrial fish farming raises many of the same concerns about chemicals and pollutants associated with feedlot cattle and factory chicken farms.

Feedlots of the Sea

Most wild-caught fish now suffer from some degree of contamination, due to widespread environmental pollution. Since most fish farms are placed in open waters or inland lakes, farmed fish are exposed to those same pollutants, but they're also fed a concoction of pesticides, antibiotics1 and other drugs.

Toxic copper sulfate is also frequently used to keep nets free of algae. All of these toxins build up in sea floor sediments and are dispersed through the environment, affecting other fish and wild sea creatures.

Despite its many drawbacks, aquaculture is booming. Between 2008 and 2013, the farmed fish industry in the U.S. grew at a pace of 5 percent per year. As noted in the featured video, better solutions are needed.

One novel invention is the aquapod — a large, predator-proof geodesic sphere that can withstand being placed further out in the ocean. By dispersing the waste byproducts in deeper waters, the environmental impact is lessened.

However, in my view this is far from an ideal solution, as drugs and toxins are still being dispersed into the wild, and while it may take longer to produce adverse effects, those effects are certainly not eliminated by this method.

It's similar to dumping toxic waste barrels into deep waters in the middle of the ocean. It may be out of sight and out of mind, but that doesn't mean it has no environmental ramifications in the long run!

Land-Based Fish Farms Also Wreak Ecological Havoc

Another solution has been to place fish farms on or close to land, but recent research2 shows that this isn't the answer either. As reported by CBC News:3

"The only peer-reviewed study examining the environmental impacts of Nova Scotia land-based fish farms has found some negative effects on downstream ecosystem.

A now-defunct unit of Environment Canada conducted research at five sites in 2011 which grow juvenile fish for transfer later to open ocean pens ...

Lead researcher Benoit Lalonde said they looked at the health of benthic invertebrates, 'the building blocks of what lives in the river or the stream' in areas where water that passed over hatcheries flowed ...

Researchers found significant changes in biodiversity ... [T]he only species that flourished were 'pollution tolerant species' ... 'What we lost there were all the sensitive species,' he said."

Humans living next to fish farms also suffer ill effects. In Vietnam, more than 100 families living near a canal that houses two fish farms report suffering from an array of diseases linked to water pollution.4

Prior to the installation of these fish farms, the water in the canal was clean and usable, but within a span of just two years, the farms have destroyed the water quality to the point that residents have to boil the water just to be able to bathe in it.

Half of All Farmed Fish Suffer Genetic Mutations and Deformities

Research also shows that farm-raised fish tend to develop all sorts of mutations, suggesting this method of farming is too far from nature's ideal. Some of the mutations have been linked to the pesticides used to combat sea lice and other pests, as these chemicals have been found to also affect the fishes' DNA.

According to Kurt Oddekalv, a respected Norwegian environmental activist, about 50 percent of farmed cod are deformed, and female cod that escape from farms are known to mate with wild cod, spreading the genetic mutations and deformities into the wild population.

Similarly, a recent study5 published in the journal Scientific Reports found that half of all farm-raised fish examined had deformed ear bones, which causes hearing impairment.

In larger, older fish, the odds of this deformity were even higher. Among farm-raised salmon weighing more than 9 pounds, all had this deformity in at least one ear. As reported by Newsweek:6

"The otoliths (ear bones) of these fish vibrate at a different frequency than the rest of the animal's body and are used to pick up and measure sound waves ...

In healthy fish, these bones are composed of aragonite, a crystalline form of calcium carbonate. But as Reimer and colleagues found, many of these otoliths were deformed and composed of a different material — vaterite.

Vaterite is also made up of calcium carbonate, but in an irregular and less dense crystal structure, thus changing the way that sound is absorbed and processed ... The presence of these vaterite deformities was 10 times higher in farmed fish than in wild animals ... "

What's Causing the Ear Bone Deformities?

The cause for these ear bone deformities is still unknown. Researchers suggest it may be triggered by some dietary factor, or may be related to their abnormally increased growth rate. Genetics is another possibility, and the researchers hope to investigate all of these hypotheses.

While hearing loss may seem like a deformity of no consequence in farmed fish, it can indeed have adverse consequences. Most farmed fish will never be released into the wild where they'd have to fend for themselves and find their own food.

But some, such as Pacific salmon, are raised in hatcheries only to be released into the wild in order to repopulate the species. As noted by Newsweek:7

"Allison Coffin Ph.D., a researcher at Washington State University who wasn't involved in the study, says the deformity could possibly affect the survival of fish released to the wild ...

Importantly, though, the study provides 'more evidence hatchery conditions are causing problems with the fish, and we need to figure out what we're doing,' she says."

Farmed Salmon Has Many Other Abnormal Features, Including Highest Toxic Load of Any Food Tested

Farmed salmon also suffer other disturbing mutations. The flesh of the farmed salmon is "brittle," and breaks apart when bent — a highly abnormal feature. The nutritional content is also wildly abnormal, which may have consequences for your health. Wild salmon contains about 5 to 7 percent fat whereas the farmed variety can contain anywhere from 14.5 to 34 percent.

Many toxins readily accumulate in fat, which means even when raised in similarly contaminated conditions, farmed salmon will contain far more toxins than wild.

This elevated toxicity is quite significant. According to toxicology researcher Jerome Ruzzin Ph.D., in Norway, farmed salmon is one of the most toxic foods in the world! Overall, tests show farmed salmon contain five times more toxins than any other food product tested.

Shockingly, research reveals that the most significant source of toxic exposure is not actually the pesticides or the antibiotics, but the dry pellet feed. Pollutants found in the fish feed include dioxins, PCBs, and a number of different drugs and chemicals. The source of these toxins originates in the fatty fish used for the feed — fish that cannot be sold for direct human consumption due to their elevated pollution levels. These pollutants then get incorporated into the feed pellets.

Another problem stems from the manufacturing process. The fatty fish are first cooked and separated into protein meal and oil. While the oil has high levels of dioxins and PCBs, the protein powder further adds to the toxicity of the end product. To the protein powder, an "antioxidant" called ethoxyquin is added.

This chemical was developed by Monsanto in the 1950s — as a pesticide — and it really does not belong in fish food. In fact, Europe has strict regulations on this pesticide in other foods, such as fruits and vegetables.

The chemical helps prevent oxidation, which is why fish pellet manufacturers secretly began using it as an "antioxidant," but the effects of this chemical on human health have never actually been established. However, the one and only study ever done on ethoxyquin and human health found it has the ability to cross the blood brain barrier, and may have carcinogenic effects.

Farm-Raised Salmon Have Different Genetics Than Wild

Interestingly, recent research8,9 also shows that salmon born in hatcheries have vastly different genetics than those born in the wild. Turns out salmon adapt to captivity extremely fast. Within a single generation, their genetic makeup changes, and with it their natural ability to thrive and reproduce in the wild.

This is a problem, as not all farmed salmon are destined for the dinner plate. In areas like Oregon and Washington, salmon are bred in hatcheries and then released into the wild to replenish wild salmon populations.

Surprisingly, the researchers found no less than 700 different genetic differences between the hatchery-born salmon and the wild-born ones. The salmon tested was the steelhead trout. In the wild, these fish are solitary and territorial creatures. In fish farms, they're raised under densely packed conditions, and in a single generation they not only lose some of these instinctual traits, they also develop improved immune function and wound repair mechanisms.

According to lead researcher Michael Blouin: "This pretty much settles the question of whether hatchery fish can be genetically different after just a single generation of domestication. What is important is that this work is a step towards trying to figure out which traits are under strong selection in the hatchery, and what hatchery conditions exacerbate that selection."

Beware of Farm-Raised Catfish

Farm-raised catfish also tend to be loaded with dioxins, and the feed is the source here as well. As noted by Nutrition Facts:10

"In the 1990s, a supermarket survey found the highest concentrations of dioxins in farm-raised catfish. The source of dioxins was determined to be the feed, but that's surprising, since catfish aren't fed a lot of animal fat. Turns out it was dioxin-contaminated clay added to the feed as an anti-caking agent, which may have originally come from sewage sludge ... so, what may have started out in sewage sludge ended up on the plates of consumers in the form of farm-raised catfish ... "

The Food and Drug Administration (FDA) requested ball clay be discontinued from use in fish feed. But they didn't actually ban or restrict it. As a result, no industry changes were made, and a belated 2013 follow-up investigation discovered that 96 percent of farmed catfish is now contaminated with dioxins. In the initial survey11 in 1997, only one-third of the catfish samples contained dioxins, so the problem has vastly escalated.

And, while imported fish often tends to be more contaminated than U.S. fish, this was not the case with catfish. Catfish imported from China or Taiwan was in fact 10 times less contaminated than those raised in the U.S.

As noted by Nutrition Facts: "[W]hen they checked the feed fed to U.S. catfish, more than half were contaminated, and so, it seems likely that mined clay products are still being used in U.S. catfish feeds ... This is a good illustration of how we can't necessarily rely on regulators to protect our families' health."

Genetically Engineered Omega-3 Crops Have Devastating Effects on Butterflies

It seems the more scientists try to "fix" things, the worse it gets. To substitute omega-3 oils from fish, genetically modified (GM) canola and camelina that contain omega-3 have been developed. The U.K. approved GM camelina in 2014, and it's being promoted as an omega-3 supplement for both humans and farmed fish. Professor Johnathan Napier Ph.D., who led the GE project at Rothamsted Research, hailed the GM crop as a "truly sustainable" source of fish farm feed.

Alas, these crops turn out to have devastating ecological consequences. While reducing the burden on fish stocks seemed like a good idea, recent research has shown that when long chain omega-3 fatty acids found in fish oil (EPA and DHA) are fed to the cabbage white butterfly — which feed on canola and camelina — the insects grew heavier and suffered a high frequency of wing deformities. As noted by the Cornucopia Institute:12

"The problem with GM omega-3-producing crops lies in the fact that genetic engineers have introduced a compound from the sea into a terrestrial environment. Neither this butterfly nor any other invertebrates that feed on these plants have ever been exposed to these molecules in their diets.

Some might rejoice that such GM omega-3-producing crops will have the unexpected added benefit of harming a butterfly that is considered to be crop pest. But that would be to ignore the potential effects on beneficial insects such as non-pest butterflies, bees, and other pollinators. It is also not known what effects may occur further up the food chain, such as on predators that consume such insects ...

The lesson to be learned from the new study seems to be that we should be wary of the claims of genetic engineers that their products are safe and sustainable when those claims are not substantiated through rigorous testing.

In making such claims, they often restrict their framework to narrow and self-serving considerations, such as whether the GM crop expresses the desired trait and delivers an acceptable product when fed to livestock — in this case, farmed fish. They ignore the wider context in which the GM crop is grown and consumed. In this way, the genetic engineer's claimed 'sustainability' success can turn out to be a hazard for ecosystems."

Fish Farms Create More Problems Than They Solve

It's become quite clear that fish farms are not a viable solution to overfishing. If anything, they're making matters worse, destroying the marine ecosystem at a far more rapid clip to boot ... So what's the answer? Unfortunately, the vast majority of fish — even when wild-caught — is too contaminated to eat on a frequent basis. Most major waterways in the world are contaminated with mercury, heavy metals, and chemicals like dioxins, PCBs, and other agricultural chemicals that wind up in the environment.

Radiation from the leaking Fukushima power plant in Japan is another concern, and many have simply given up on eating fish for fear of radioactive contamination, or they opt for farmed fish, thinking it's a safer option. Based on the evidence, choosing farmed fish to avoid radiation is not going to do your health any favors. You may avoid nuclear radiation, but you're getting far more of other toxins instead.

One answer to this conundrum is to contact the distributor of whatever wild fish you may be interested in, and ask them whether or not they test for radiation. Some companies do. Alternatively, you could get a Geiger counter and test it yourself.

Best Seafood Options: Wild Alaskan Salmon, Sardines and Anchovies

While many types of fish are best avoided these days, there are exceptions. For example, I believe the nutritional benefits of wild-caught Alaskan sockeye salmon still outweigh the risks of potential contamination. The risk of sockeye accumulating high amounts of mercury and other toxins is reduced because of its short life cycle, which is only about three years. Additionally, bioaccumulation of toxins is also reduced by the fact that it doesn't feed on other, already contaminated, fish.

Alaskan salmon is also not allowed to be farmed, and is therefore always wild-caught. My favorite brand is Vital Choice Wild Seafood and Organics, which offers a nice variety of high-quality salmon products that test high for omega-3 fats and low for contaminants. Their fish is also regularly screened for Fukushima radiation and found to be free of it. Canned salmon labeled "Alaskan salmon" is a less expensive alternative to salmon fillets.

Another exception is smaller fish with short lifecycles, such as sardines and anchovies, which I eat nearly every day. These also tend to be better alternatives in terms of fat content, so it's a win-win situation — lower contamination risk and higher nutritional value.

A general guideline is that the closer to the bottom of the food chain the fish is, the less contamination it will have accumulated. Just make sure they're not from the Baltic Sea, which is known for its exceptionally high levels of pollution. Other good choices include herring and fish roe, which are full of important phospholipids that nourish mitochondrial membranes.

[+]Sources and References [-]Sources and References

  • 1 Time October 22, 2014
  • 2 Cogent Environmental Science (2016), 2: 1136099 (PDF)
  • 3 CBC News May 9, 2016
  • 4 Viet Nam News November 2015
  • 5 Scientific Reports 2016: 6; 25249
  • 6, 7 Newsweek April 28, 2016
  • 8 Nature Communications January 7, 2016: 7; 10676
  • 9 Newsweek February 17, 2016
  • 10 April 5, 2016
  • 11 Chemosphere 1997 Mar-Apr;34(5-7):1411-9.
  • 12 Cornucopia Institute May 4, 2016