Americans may unknowingly be eating endangered sharks and other at-risk animals, a study shows. 

Researchers at the University of North Carolina at Chapel Hill carried out DNA analysis on items marketed as shark meat in local grocery stores. 

More than nine in 10 tested samples were ambiguously labeled ‘shark’ without further information on the specific species.

Alarmingly, nearly one-third of these products were actually from endangered or critically endangered shark species, heightening the risk of their extinction. 

Mislabeled items included shark steak, jelly, and jerky, selling for as low as $3 per pound, making them easily accessible. Meanwhile, costlier delicacies were priced up to $100 per pound.

Sharks are vital for preserving marine ecosystems by controlling fish populations. Without sharks preying on smaller fish, their food sources would lessen, eventually leading to the death of these fish. 

The researchers warned that in addition to threatening shark ecosystems, eating endangered sharks could also pose health risks for humans. 

Some types of hammerhead sharks, for example, have high levels of mercury in their meat and fins. 

Though safe in small amounts, mercury can accumulate in vital organs like the brain, kidneys and liver, leading to potentially irreversible damage. 

Researchers at the University of North Carolina at Chapel Hill discovered that many Americans may unknowingly consume meat from endangered species (stock image).

Several species of hammerhead sharks (pictured above) contain high levels of toxic mercury, the researchers warned (stock image)

Dr. Savannah Ryburn, the first study author and co-instructor of UNC Chapel Hill’s seafood forensics class, which performed the research, stated: ‘Mislabeling and ambiguous labeling deprive consumers of the ability to choose what they are consuming.’

‘For example, two species in our study, scalloped hammerhead and great hammerhead, were ambiguously labeled as “shark,” even though they are strongly advised against consumption due to their very high mercury levels. 

‘Without accurate and precise labeling, consumers cannot avoid purchasing these products.’

The study, published Tuesday in the journal Frontiers in Marine Science, looked at 30 shark product samples purchased from grocery stores, Asian markets, seafood markets and online retailers in Washington DC, North Carolina, Florida and Georgia. 

Samples included 19 raw shark steaks and 11 packages of shark jelly, a substance found in the pores of a shark’s snout that helps them detect electric fields. 

It’s unclear if any of the samples were from illegally hunted sharks.

The team was able to successfully perform DNA testing on 29 out of 30 samples to determine the exact species. Of those, 27 were ambiguously labeled ‘shark’ and did not specify the species.

The 29 shark samples were made up of 11 species, four of which were endangered or critically endangered: great hammerhead, scalloped hammerhead, tope (also known as the school shark) and the shortfin mako shark. 

The International Union for Conservation of Nature (IUCN) has found the population of great hammerhead and scalloped hammerhead sharks has declined by over 80 percent in the last 70 years. Some research suggests fewer than 200 of each remain. 

Meanwhile, the tope shark population is critically endangered and has dropped by about 88 percent in the last 80 years. 

The shortfin mako shark is considered endangered, with estimates suggesting the population has dropped between 60 and 96 percent, depending on the area. 

Pictured above are how several of the tested samples were labeled and displayed at stores. Many of them were ambiguously labeled

The above graph shows the number of samples tested and how endangered each species is

The others were from another seven species, including the vulnerable spinner, lemon, common tresher, and blacktip shark, and the near threatened smooth-hound and Pacific angelshark. 

Only one was from a least concern species, the Atlantic sharpnose shark. 

Experts have largely blamed declining shark populations on overfishing due to higher demand of shark fins and meat. They also reproduce slowly and live between 20 and 30 years, making it difficult for populations to recover. 

Only one tested sample for a blacktip shark was labeled correctly, suggesting the majority of samples sold online and in stores did not disclose that they were potentially endangered species. 

Sharks are apex predators that help regulate populations of prey, which in this case includes smaller fish. If prey populations become too large, they can eat away at coral reefs and deplete food sources faster than they can be replenished, eventually causing the prey to die as well.

The researchers warned scalloped and great hammerheads are also high in mercury, a heavy metal found in the earth’s crust. It is a neurotoxin, meaning it accumulates in and attacks the nervous system. 

Over time, mercury exposure can lead to mood changes, memory loss, tremors, paralysis and vital organ damage. 

Dr Ryburn said: ‘Sellers in the United States should be required to provide species-specific names, and when shark meat is not a food security necessity, consumers should avoid purchasing products that lack species-level labeling or traceable sourcing.’