Fish lovers may have mixed thoughts about the results of a new global study. Researchers from Scripps Institution of Oceanography at UC San Diego found that fish populations across the world's oceans are contaminated with toxic pollutants.
However, the researchers also found that the concentrations now are significantly lower than in previous years.
The study focused on the amount of persistent organic pollutants (POPs), which come from industrial and agricultural interventions. The researchers analyzed hundreds of peer-reviewed papers published from 1969-2012. The articles looked into the patterns of POP concentrations and found that it is significantly variable.
Their analysis covered old chemicals such as mercury and DDT, as well as new ones like coolants and flame retardants.
The researchers found that mercury concentrations were at the level of threshold set by the Environmental Protection Agency (EPA), while DDT concentrations were at a much lower degree.
"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," says co-author Stuart Sandin.
The values were sometimes so high that concentrations in some regions varied by a thousandfold. Therefore, consumers remain at risk of being exposed to pollutant levels above the EPA screening values.
Despite POPs being present across the world's oceans, the researchers say it is not all bad.
The study shows that the concentration of POPs was much more elevated in the 1980s than it is today. In fact, the researchers were able to note a drop of about 15-30 percent every 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," co-author Lindsay Bonito says. However, there's still a chance that people may eat fish as contaminated as before.
The researchers say that the positive progress signifies that the global community has heeded calls to action to reduce the amount of toxic chemicals released into the environment.
The study was published in the journal PeerJ on Jan. 28.