tests on laboratory animals such as mice indicate that their effects can be considerable, attacking the sex and thyroid glands, motor skills and brain function.
so, it seems not only is the population count shrinking, but we're ending up with cross-gendered bears who aren't very adapt at.. well, much of anything at all if the results shown from the statement above are borne into them crazy polar bears as well!
want to feed your morbid curiosity? or maybe you're just concerned about wildlife? but, most likely both.. lol..
anyhoo, whatever your case may be..
here's the link.