Persistent organic pollutants (POPs) are having a toxic effect on the health of endangered polar bears in the Arctic, researchers have warned through a study published in the journal Environmental Toxicology and Chemistry.
Pollutants can be categorised into different types based on how long they say in the environment and worst of them all are the POPs that remain intact in the environment for years. These POPs do not originate in the Arctic, but they reach there by travel long distances by accumulating in living organisms, and getting transported via air, water, migratory species and technical matrices such as products and wastes.
Researchers have found through their study, which is the first attempt to quantify the risk of POPs on the Arctic ecosystem, there is a very toxic effect of these POPs on polar bears and their offspring in the Arctic. Scientists from University of Milan in Italy have found that most POPs may have endocrine-disrupting effects, as a result of which the growth and development of bear offspring may be endangered.
Besides, the most important complex groups of POPs (PCBs, polychlorinated dibenzodioxins/dibenzofurans [PCDD/Fs]) some individual chemicals (or small groups), such as chlordanes, aldrin, and dieldrin, also reach a very high hazard quotient level. In particular, for bear cubs some hazard quotient values are close to or even higher than 100.
However, in comparison with the 1980s, a decrease in risk from legacy POPs has been evident for bear cubs, mainly because of international control measures. But, the composition of POPs substantially changes and the contribution of new POPs (particularly perfluorooctane sulfonate) is increasing.
“The results demonstrate that international control measures are effective at reducing the risk to ecosystems. Nevertheless, it is fundamental to continuously implement the control of new and emerging contaminants,” said Marco Vighi from the University of Milano-Bicocca in Italy.