The Horrible Truth About Farmed Salmon

They should tell you this stuff beforehand so you don't have to kill your sushi chef.

Note: Apologies for the rerun. I’m tanning naked and betting on coconut crab races on an island in the South Pacific.

Let’s say you and the missus, or perhaps more accurately, the mistress, want to paint your BDSM dungeon, only you can’t decide on the exact shade of lustful yet foreboding red. The logical thing would be to drive down to the closest Sherwin Williams and check out their color samples or, better yet, pick up one of their newly redesigned fan decks that shows nearly every conceivable shade of red (or any other color) imaginable.

After all, that’s pretty much what salmon farmers do when they want to choose a color for the salmon they raise.

The flesh of farm-raised salmon isn’t pink, red, or orange. Instead, it’s the color of gym socks or old underwear. Wild salmon get their iconic color from the krill they eat, which farm-raised salmon aren’t privy to.

There’s nothing magical about the krill, though, they simply contain rich amounts of astaxanthin, a carotenoid that’s fairly common in nature. It’s presence in wild salmon isn’t only cosmetic, though -- astaxanthin is a powerful antioxidant that protects the fish from stress, strengthens its immune system, and contributes to its development.

Enter the chemical company Hoffman La Roche. In the 1970’s, they developed a synthetic version of the carotenoid and started large-scale production, which allowed the farmed salmon industry to add it to their salmon feed and give their product a more appealing color.

But like the good little enterprisers they were, the company wanted to give salmon farmers some choice. The result was the Roche SalmoFan, a color fan deck very much like those seen in Sherwin Williams and other paint stores.

The fan deck allows farmers to choose from any of 14 shades, ranging from orange to blood-red. These shades are manufactured by using varying amounts of astaxanthin, along with a sprinkling of canthaxin, another carotenoid that’s yellowish.

Despite all the available choices, shades 33 and 34 remain the favorites, as the votes of focus groups indicated that those deep red hues were most associated with freshness and quality, even though the color has nothing to do with these attributes.

(Just as an aside, famed con man PT Barnum once found himself in possession of a truckload of white salmon. He parked it and put a sign outside reading: “White salmon. Guaranteed to not turn pink.” This was his attempt, ultimately successful in the short-term, to convince the uninformed customer that the pink color was in fact a defect.)

Early in the 2000’s, though, canthaxin was found to possibly stain the retina of the humans who ate the salmon, along with causing potential vision loss. As such, the European Union forced salmon farmers to use less of the yellowish dye.

But that’s just one of the many “quirks” associated with the salmon farming industry, some of which can affect human health and some of which are, if you’ve got an ounce of humanity, just horrific.

What Exactly is Salmon Farming?

Salmon farming is a three-stage process. First, salmon eggs are hatched in freshwater tanks where they’re raised for 12 to 18 months. They’re then transferred to ocean cages along the seashore until they’re ready for “harvest.”

A typical salmon ocean cage is built of metal or plastic and covered on the sides by mesh netting. They’re usually 30 to 90 feet wide and about 30 feet deep. Each cage holds up to 90,000 salmon, making the population density equivalent to a New York City subway train during rush hour. The fish are fed pellets made of other fish, fish oils, nutrients, the aforementioned coloring agents, and, if needed, antibiotics and medicine (and they usually are needed).

The farmers stop feeding the fish about a week before harvesting. This gives the salmon time to eliminate all the waste in their digestive systems. They’re then rounded up and placed in water that’s rich with carbon dioxide. This “anesthetizes” the fish so that they’re presumably numb to having their gill arches cut out, which causes them to bleed out. They’re then quickly dumped into an ice slurry. From there, they’re gutted and processed.

Incidentally, these salmon, known either as Atlantic salmon, Norwegian salmon, Scottish salmon, Chilean salmon, etc., depending on whose coast they’re grown off, aren’t the same as Pacific or Alaskan salmon. They’re not even the same species. While there are five species of Pacific salmon, there’s only one species of Atlantic salmon (salmo salar).

Pacific salmon tend to have a richer flavor, but the biggest difference is that Pacific salmon tend to be wild caught and most Atlantic salmon come from farms. The latter is significant to me as I’ve decided to never eat farm-raised Atlantic salmon again.

Below are my reasons:

A Louse-y Way to Die

“Sea lice,” which are actually crustaceans, more specifically, copepods, collectively comprise the largest animal biomass on earth, or so say some scientists. Two species of these copepods, however, specifically seek out salmon to infest. After these sea lice reach their intermediate stage of development, they have approximately 10 days to find an accommodating salmon before they die, but this is problematic in open waters because salmon swim by fast. It’s like trying to jump onto a bus without the driver slowing down… or opening the door.

However, things are very much different in salmon farms. Because of overcrowding and fat, lazy salmon, the lice can pretty much catch any “bus” they want to, and they do. They have two “antennae” which latch onto the fish. They then use their razor-like jaws to gnaw into the mucosa, skin, and tissues of the fish.

Once the lice eat through the skin, saltwater flows into the open wounds, causing the fish to lose moisture and compensate by drinking more. This bleeding also attracts bacteria, which causes infections.

Now, having one louse or two probably won’t affect a healthy salmon, but some farmed fish carry as many as a hundred or more. They often eat all the flesh off a salmon’s skull. In Norway, these fish are called “kvitskaller,” or “white skulls.”

As such, salmon farmers go to considerable lengths to combat these lice. In Norway alone, costs attributed to “delousing” exceed 500 million dollars a year.

At first, salmon farmers used Neguvon, an organophosphate that acts like nerve gas. They’d simply dump tons of the stuff directly into the salmon pens. At first, it killed 95 percent of the lice, then 80. Eventually the kill rate dropped down to 60 percent. It turns out the enemy was incredibly resilient and resourceful.

Besides, the chemical also killed a great deal of salmon.

Next, they tried hydrogen peroxide. Undiluted, the stuff is incredibly corrosive and can even eat through metal. In sufficient amounts, again dumped straight into the ocean water, it caused the lice to go blind and then blow apart. However, as the lice grow resistant, the farmers had to use larger and larger amounts.

Enter pyrethrins, another type of poison, followed by chitin inhibitors that would prevent the lice from growing their exoskeletons. And then emamectin benzoate. Then a flea agent, lufenuron. Each time, the lice would rebound, each time more virulent, more aggressive, and more pathogenic.

A log kept by Norwegian authorities indicated that over the years the ocean had absorbed 120,000 metric tons of hydrogen peroxide, 116 million tons of Neguvon, 10 metric tons of dichlorvos, 1.5 metric tons of emamectin, 2.5 metric tons of pyrethroids, 43 metric tons of chitin synthesis inhibitors, and 27 metric tons of azamethiphos.

Some of this residue ends up in the fish (and, by extension, you when you eat them) and some falls to the seabed below the pen. There, the chemicals join the excess feed, excrement, and decomposing fish to form a pile that drives away all other marine life for hundreds of yards. The authors of a study on the perils of salmon farming found a photo of a yardstick shoved into the pile of slime underneath the pen. All that was visible were the top four inches of the stick.

And the amounts of chemicals listed are for Norway only. The other farms around the Atlantic are probably no different.

How these chemicals might affect other sea life hasn’t been taken into consideration. How it might affect humans who ate the salmon also hasn’t been taken into consideration and research is scant.

Exploding Hearts and Couch-Potato Fish

You’d naturally think the sea lice is the biggest killer of farmed salmon. It’s not. The primary reason salmon die before harvest is that, well, their hearts explode.

In 2007, Mowi, the world’s biggest seafood company, figured out that around two hundred metric tons of salmon died of “cardiac rupture” every month.

Wild salmon have rigid, pyramidal hearts that can compensate for nearly any amount of athletic activity. Farmed salmon have hearts that are rounder, but they’re often malformed. Some are bean shaped and small. Some are twisted, S-shaped. Some are shaped like bells or bottles.

Much of this is caused by a virus called piscine myocarditis virus (PMCV) found in the hearts of farmed salmon. It causes the walls of the salmon heart to become thin and fragile, making the atrium wall susceptible to breaks. Once it does, blood pours into the pericardium. The salmon thrashes and jerks for a few moments and then sinks quietly to the bottom of the pen.

To complicate things, farmed salmon live lives of leisure. They have plenty of food and because they’re virtually weightless in water, they don’t exert much energy, i.e., they don’t get much exercise. Like many human couch potatoes, they also have fatty deposits in their hearts.

As such, their hearts are ill-equipped to handle stress, so when it occurs in the form of stormy weather, being crammed into fish carriers, or delousing (more on that later), their hearts explode.

If the fish don’t die from exploding hearts and the virus is unchecked, it can spread to the kidneys, gills, muscles, and blood cells. Unfortunately, if a fish is affected, it will never be healthy again. Farmers are quick to slaughter these fish before they succumb to the virus because fish that died can’t be sold as food.

Pesky rules.

Fish on the Run

Another problem faced by the salmon industry is the escape of fish. Economically, it’s hardly an issue when a few farmed fish go on the lam, but it can have huge ecological implications. Namely, these decidedly weak fish can breed with wild salmon (which are already practically an endangered species) and weaken the whole damn lot of them.

As such, some salmon farmers attempted to sterilize their livestock. However, there intentions aren’t purely ethical. Sexually mature salmon, you see, eat less. They grow slower. They’re less red.

Their solution was to make the farmed salmon triploid. That means they gave them three sets of chromosomes, thereby making them infertile. Seedless watermelons are triploid, as are bananas and certain apples.

This was accomplished by subjecting the roe (fish eggs) to water that had been heated to 82 degrees for a few minutes.

The trouble is triploid fish are gimpy. They have short jaws that tilt inward, making them look like pug dogs. In Chile, they call them “screamers” because they remind the farmers of Edvard Munch’s painting, The Scream.

A deformed mouth meant slower growth. Sometimes the eyes of the fish were cloudy, so they couldn’t see their feed. Some had skeletal deformities like crooked, twisted spines.

There were scientists that regard these triploid salmon as a new species, but sushi consumers were never told about it.

The Salmon Industry Goes “Green”?

Some unknown salmon researcher, working for the farmed salmon industry, noticed that wrasse, aka “cleaner fish,” ate sea lice; plucked them right off passing salmon.

So, they wrangled up millions of wrasses. According to Norwegian statistics, 28 million of them were caught for use in Norway, (and probably millions more by other countries).

Unfortunately, it doesn’t work as well as they’d hoped. For one thing, they were dumping millions of stressed fish into pens populated with predatory fish. The smaller ones just swam through the netting and escaped. Some, when transported too far north, couldn’t handle the temperature and their brains shut down.

An estimated 50 million wrasse die each year, the victims of the salmon industry.

While some farmers continue to use wrasse to delouse their salmon, others turned to thermal delousing, and by the year 2020, it was the most common way to get rid of salmon lice. The fish are placed in water that’s been heated to 93 degrees but sometimes as high as 97 degrees. This causes most of the lice to detach.

However, salmon can only tolerate temperatures up to 86 degrees. When placed in 93-degree water, they panic. They swim frantically in circles and collide with other fish. They can withstand the pain for just under two minutes before going “belly up.”

Thermal delousing becomes a delicate balance between life and death, too low a temperature or too short an exposure and the lice survive. Too high a temp and too long an exposure and the salmon die.

The battle against the sea louse continues.

Fish Food and Omega-3s

The fish meal fed to salmon consists of anchovies, sardines, mackerel, herring, and other small foraging fish. The industry uses so many fish that a full quarter of the fish harvested from the ocean wind up in feed for salmon (or aquaculture in general) and pets.

What the industry is doing is taking food from the people of West Africa largely to feed the people of the U.S. and Europe. However, the use of these foraging fish to make salmon feed is diminishing, but not because of any humanitarian or ethical considerations.

The supply simply can’t meet the demand. As such, feed manufacturers are instead using increased amounts of vegetable oil in fish feed. This results in lower levels of the omega-3 fatty acids that are the main reason many of us eat salmon in the first place.

It also does to salmon what the beef industry did to cattle. Long ago, when cattle were grass-fed and grass-finished, the meat had an omega-6 fatty acid ratio to omega-3 ratio of two-to-one or even one-to-one. Since feeding grass and hay to large numbers of cattle is often problematical, cattle ranchers began using corn and barley, which changed the fatty acid ratio to somewhere around 20-to-1.

This skewed fatty acid ratio is thought to be at least partly responsible for chronic inflammation and a slew of chronic diseases in the humans who eat a lot of beef.

If the use of this exchange of fatty acids continues or accelerates, eating farm-raised Atlantic Salmon won’t be any better for your heart than eating a cheeseburger.

Other Considerations

A comprehensive study in Science reported that farmed Atlantic salmon had unacceptable levels of PCBs and dioxin and that people shouldn’t eat the stuff more than three times a year.

As a refresher, PCBs are “forever” chemicals that were widely used between the years 1929 and 1979, after which they were banned. The trouble is, true to their “forever” descriptor, they’re still around. To be fair, they’re everywhere, but salmon might be particularly prone to accruing large amounts.

The “feeder” fish that are used to make salmon feed are continually absorbing PCBs through the food they eat, and these chemicals then become concentrated in farmed salmon. The same thing is true of dioxin, another forever chemical that can cause problems in humans.

The European Union objected mightily to these accusations. Whether their objections were based on science or plain greed is unknown, but they thought the Canadian and U.S scientists behind the report were over-reacting and that the levels of PCB and dioxin in farmed salmon were well within WHO and EU guidelines. Further, they recommended people eat two servings of fish a week, one of which should be (farmed) salmon.

The jury is still out, but other studies have also sounded the alarm, writing that farmed salmon contains up to 16 times the PCB found in wild salmon.

So, Bottom Line, Should You Eat Farmed Salmon?

I think I’ve presented some health reasons and some ethical reasons not to eat farmed salmon. There’s the “artificial” color, the chemical residues, the genetic manipulation, the PCBs and dioxins, the Mengele-esque experimentation, the diminution of omega-3s, the depletion of ocean foodstuffs, the general pollution of the oceans, and the failure to inform of what exactly the fuck we’re eating.

All of that has to be taken into consideration when deciding whether to continue eating Atlantic salmon. However, if you choose to give it up, I’m at a loss when it comes to suggesting an alternative.

Let’s say we all switched to eating wild-caught Pacific salmon; threatened our sushi chefs and grabbed their wasabi-stained double-breasted jackets if they didn’t comply. That would likely lead to a huge shortage of Pacific salmon (more so than already exists). The fish might reach extinction levels, forcing them to do with Pacific salmon what they did with Atlantic salmon. At the very least, it would likely lead to exorbitant prices.

Unfortunately, this is the world we live in. Nearly everything is a complex equation where we have to grapple with moral decisions that may or may not impact our health, let alone the health of the world.

May God -- or your better self -- grant you the wisdom to choose correctly.

There is hope, however. A new technology allows prospective salmon farmers to construct “sustainable” salmon farms inland. These new farms are built of concrete and are filled with freshwater that recirculates through biofilters every half hour, thus negating the need for

de-lousing chemicals or de-lousing procedures, along with most medicines and antibiotics.

The tanks are lit with faint aqua blue light to mimic an aquatic environment and after 18 months in the tank, the fish can be sold directly to restaurants.

So far, these tank-raised fish are only available in local markets, most of them in Florida, New York, and Wisconsin, but Brian Vinci, director of the Conservation Fund’s Freshwater Institute, believes that we’re “25 to 30 years away from replacing 50 to 70 percent or our imported farmed salmon with domestically raised fish.”

That may be a case of too little, too late, but it’s at least something to hang our hopes on. In the meantime, start asking your sushi chef and your restaurant server exactly where their salmon comes from.

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Sources:

Simen Saetre and Kjetil Ostli, “The New Fish,” Patagonia, 2023.

“EU Backs Farmed Salmon Safety,” Food Navigator Europe, 2023.

Elizabeth Cha, “The 15 Colors of Salmon,” Wired Magazine, Feb. 1, 2004.

Douglas Franz and Catherin Collins, “3 Reasons to Avoid Farmed Salmon,” Time Magazine.

“PCBs in Farmed Salmon,” EWG, July 31, 2003.

Melissa Clark, “The Future of Salmon is Dawning on the Land,” The New York Times, October 18^th, 2023.

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