A new study found that chemicals that have not been produced in the United States for years or even decades are still found in the bodies of migratory terns.
Scientists at the University of Buffalo have begun work to study the level of chemical contamination in eggs of common terns and other wild water birds.
Scientists have found all three types of chemicals in the organs of more than two dozen common terns in spawning grounds along the Niagara River and on the shores of Lake Erie. Contaminants have been found at different stages in the life of birds: in chickens, juveniles and adults.
The researchers also discovered the chemicals in the fish, which is the main food source for terns in the area.
“These chemicals are still there. They won’t just disappear. For example, PCBs (polychlorinated biphenyls) have long been discontinued in the US, but you can still find them in the environment, in sediment and water. They do not decompose for years. The fish eat the organisms that store them, and then the birds eat the fish”.
Henry M. Woodburn, Ph.D., professor of chemistry at the University of Buffalo
The authors write in their paper that the levels of chemicals in the birds were high enough to potentially harm health and affect population recovery.
The findings show how household and industrial chemicals have become ubiquitous in the environment. In it, these compounds can persist for many years, posing a threat to wildlife. In the case of terns, the threat starts from the very first moments of their lives, even before they hatch.