Since we tend to eat the same fish as these marine predators, this is bad news for humans, too.
"What humans do doesn't just affect us where we are directly," she added. "It has worldwide implications. It's one world. It's not just your little spot."
Toxic chemicals are accumulating in the bodies of dolphins and whales, according to two new studies, and concentrations tend to be highest in the most populated and developed areas.
The research may also help illuminate potential threats to human health.
A number of studies in recent years have revealed a variety of toxic pollutants in dolphin blubber, including PCBs, PBDE flame retardants and the pesticide DDT.