Printer Friendly

Are pollutants shrinking polar bear gonads?

The more polluted a polar bear's fat, the more likely its reproductive organs will be undersize, scientists find.

They collected gonads from 55 male and 44 female bears killed legally by subsistence hunters in east Greenland. The scientists then tested the bears' fat for pollutants that might affect sex hormones.

Especially in immature males, testis length diminished with increasing concentrations of many of these compounds, including DDT, polybrominated diphenyl ether (PBDE) flame retardants, and banned termiticides called chlordanes. The weight and length of the baculum, a bone that supports a bear's penis, also decreased significantly with increasing concentrations of some of the compounds.

Ovary length diminished with increasing PCB and chlordane concentrations, and ovary weight decreased with increasing PBDEs, the team reports an upcoming issue of Environmental Science & Technology.

Although studies had suggested that some of these agents might affect animals' reproduction, "this is the first time it has ever been shown outside the laboratory," says Christian Sonne of Denmark's National Environmental Research Institute in Roskilde, who led the new study.

"There's no doubt" that some of the sex-organ changes observed would impair reproduction, he says. The same pollutants might be related to the falling fertility of men in many countries (SN: 1/22/94, p. 56), he adds.--J.R.
COPYRIGHT 2006 Science Service, Inc.
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2006, Gale Group. All rights reserved. Gale Group is a Thomson Corporation Company.

Article Details
Printer friendly Cite/link Email Feedback
Publication:Science News
Article Type:Brief article
Geographic Code:1GREE
Date:Sep 9, 2006
Words:211
Previous Article:High-protein diets boost hunger-taming hormone.
Next Article:Old drug can stop clots as well as newer drug does.
Topics:


Related Articles
Solar bear technology.
Bear evidence of omega-3's benefits.
The gender benders: are environmental 'hormones' emasculating wildlife?
WHITE BEARS, BLACK OIL.
Ministry invests in polar bear park.
Northern timeshare. (Ear To The Ground).
Polychlorinated biphenyls and reproductive hormones in female polar bears at Svalbard. (Research).
Comparison of biochemical composition and muscle hypertrophy associated with the reproductive cycle of diploid and triploid scallops, Argopecten...
Three times the charm.

Terms of use | Privacy policy | Copyright © 2019 Farlex, Inc. | Feedback | For webmasters