Why is shark meat dangerous and how does the meat become toxic?

As we continue to contaminate the oceans, fish and other marine life absorb some of the bio-toxins and heavy metals. These toxins multiply each time they move higher in the food chain, a process known as biomagnification. Being at the top of the food chain, as sharks feed on different marine life, many which have already fed on other smaller fish, they begin to accumulate high levels of mercury and other toxins that become unsafe for us to consume.




Is it safer to eat younger meat?

Many suggest the solution is to only eat sharks under a certain size, arguing that they haven’t had a lot of time to accumulate these dangerous contaminants, or at least not very high levels of them. While this may keep the consumer “safer” from certain metals and toxins, others like PCBs and DDTs can be passed to infant sharks through their mothers’ fatty tissues. PCBs and DDTs haven’t been produced in 30 years but we have yet to eliminate it from our rivers, lakes, and coastal areas where it has been contaminating fish and sharks. PCBs, which were primarily used as cooling fluid for electrical equipment and machinery back when it was legal, can cause birth defects and studies have linked it as potentially toxic to immune systems, reproductive organs, and thyroid. DDTs were used as an insecticide in the 1940s and for 30 years the US used over a billion pounds for agriculture and commercial industries. It can cause harmful effects to the nervous system and long term exposure can cause neurological and cognitive problems.

Another reason not to consume juvenile sharks? Sharks are slow to sexually mature, they don't reproduce early in life. Removing juvenile sharks can be damaging to the ecosystem they contribute to, not just now but in the future as well.

What other toxins can be found in shark meat & how do they affect consumers?


Although mercury can naturally occur in the ocean it is heavily released from our industrial pollutants. As it accumulates it becomes methylmercury and is absorbed by marine life.

Methylmercury bioaccumulates, staying in the consumer’s system, whether the meat is fresh or frozen. 
Toxicologist Dr. Hermann Fruse of the University of Kiel in Germany stated that mercury is “one of the most biologically active and most dangerous poisons to humans.”

What can methylmercury do to average consumers?

  • headaches

  • tremors

  • cognitive dysfunction

  • serious birth defects

  • damage to the central nervous system

  • memory problems

  • depression

  • kidney damage

  • cancer

  • brain damage


Shockingly enough even lead has been found in shark meat in extremely high levels.
Lead poisoning can cause:

  • headaches

  • pain

  • seizures

  • coma


Jann Gilbert of Southern Cross University in Australia presented findings of dangerous levels of arsenic found in shark meat as well. Gilbert studied Sandbar, Dusky, Great White, Whale, Dwarf Pygmy, and Hammerhead Sharks. They were all found to have levels of arsenic way beyond recommended consumption standards. Gilbert stated that the consumption of these species can be extremely dangerous and avoided at all costs.

This is because when consumed,  arsenic can cause: 

  • damage to the lungs 

  • skin damage 

  • kidney damage 

  • liver damage 

  • heart attack 

  • stroke 

  • cancer 

  • death


Another reason to rethink eating shark meat is high levels of urea which is secreted from shark skin. Urea being the chief nitrogenous waste from marine mammals.  It is the non-toxic nitrogen-containing substance which humans excrete in their urine which keeps the fish from drying out in salt water. 
After sharks are killed and left out of the water,  decomposition occurs which means high amounts of ammonia are produced. When the shark dies the urea deteriorates back to ammonia, so the meat will taste and smell like ammonia. In order to hide the smell, markets will drench unprocessed shark meat in milk to reduce the strong odor.

The verdict?

All personal feelings towards sharks aside, it's hard to argue that eating their meat can't cause us alarming harm both directly and indirectly! As the shark meat trade explodes overseas and we get closer and closer to wiping out sharks completely, the catastrophic effect it is having on the ocean is becoming scarily tangible. There's no such thing as a healthy shark-less ocean. The ocean needs sharks and we need the ocean, no matter how far we live from it.

  • White Instagram Icon
  • White Twitter Icon
  • White Facebook Icon
  • White YouTube Icon
  • White Tumblr Icon