A global analysis of the world's seafood by researchers from the University of California, San Diego discovered that the fish populations in the world's oceans are contaminated with industrial and agricultural pollutants, also referred to as persistent organic pollutants (POPs), although concentrations of these pollutants has been on a steady decline over the last 30 years.

The team based their findings on the analysis of hundreds of peer-reviewed articles dating from 1969 to 2012. They studied pollutants such as older "legacy" chemicals including DDT and mercury, as well as more recent industrial chemicals such as flame retardants and coolants.

"Based on the best data collected from across the globe, we can say that POPs can be anywhere and in any species of marine fish," Stuart Sandin, a coauthor of the study, said in a press release.

Despite the widespread presence of POPs in all fish in the world's oceans, the researchers claim that the concentrations present in the edible meat of marine fish varies greatly - simply moving from one region of fish to another can show a 1,000-fold variation. Furthermore, they found that concentrations of POPs were much higher in the 1980s than today, evident in the 15 to 30 percent drop seen each decade.

"This means that the typical fish that you consume today can have approximately 50 percent of the concentration of most POPs when compared to the same fish eaten by your parents at your age," said Lindsay Bonito, lead author of the study. "But there still remains a chance of getting a fillet as contaminated as what your parents ate."

Ultimately, the levels of POPs found in the fish were at or below the U.S. Environmental Protection Agency (EPA) guidelines, pointing the successful response of the global community to the release of harmful chemicals into the environment.

The findings were published in the Jan. 28 issue of PeerJ.