Study discovers that sharks contain large amounts of pollutants

Greenland Shark 005

Greenland Shark

A study conducted in Greenland found that local sharks contain alarming amounts of PCB’s and pollutants. 

Researchers from the Norwegian University of Science and Technology (NTNU) have discovered that Greenland sharks contain larger amounts of PCB’s and pollutants than polar bears, which are known for containing large amounts of pollutants.  The scientists concluded that Greenland sharks have such high levels of pollutants because they can live for 100 years.  Over their long lifespans they consume large amounts of prey that are high on the food chain, which leads to an accumulation of pollutants.

The goal of this study was to analyze behavior, distribution, population size, concentrations of pollutants and the effect of pollutants on this species of sharks.  Forty-three sharks were tagged with a tracking device and depth gauge.  The tracking devices on the sharks showed that they like to feed in areas highly populated with seals, which are high on the food chain predators.  Despite seals being high on thefood chain, sharks eat them which is a direct transfer of the pollutants inside the seals when consumed by the Greenland sharks.  Scientists were surprised to find such high levels of pollutants within the studied individuals but over a 100year lifespan many seals are consumed which is why they contain such high levels of pollutants.

This study is a great example of the saying, “You are what you eat.”  Eating organisms with high amounts of pollutants can lead to health concerns and problems.  Sharks are not the only predators with high amounts of pollutants.  During my study abroad experience in the Turks and Caicos Islands, I learned that it was unsafe to consume local barracuda and horse-eye jacks due to ciguatera or their flesh being contaminated with toxins.  This plays a big role in the local community because these fish are no longer a food source and if they are consumed the individuals who eat the fish with ciguatera get very sick.

To read more about this study click here.

________________________________________________________________________________________________________ Source:

The Norwegian University of Science and Technology (NTNU). “Sharkscontain more pollutants than polar bears.” ScienceDaily. ScienceDaily, 11 April 2014.



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