ScienceDaily (Sep. 5, 2006) — Exposure to high levels of environmental pollutants called organohalogen compounds (OHCs) seems to reduce the size of sexual organs in male and female polar bears, researchers report in an article scheduled for the Sept. 15 issue of the ACS journal, Environmental Science & Technology.

OHCs include dioxins, polychlorinated biphenyls and some pesticides.

Christian Sonne and colleagues checked 55 male and 44 female East Greenland polar bears for a correlation between OHC levels in body tissue and size of sexual organs.

Sonne's group did the study to close gaps in knowledge about the OHC's possible effects on reproduction in polar bears, a vulnerable population because of their low reproductive rates. The bears have elevated OHC levels, due to a diet that includes seals, which accumulate large amounts of OHCs in their blubber. Past studies have linked OHCs to various health effects in the bears.

The new study reports a connection between OHC levels and reduced size of the uterus in female bears and reduced size of the testis and baculum (penis bone) in males. A large baculum is critical for successful mating in an arctic climate, the researchers note, and even slight decreases may interfere with reproduction.

"Furthermore, similar physiological impacts from organohalogen-pollutant exposure may be manifested on the reproductive tract of humans relying on OHC-contaminated food resources," the study states.

Reference: "Xenoendocrine Pollutants May Reduce Size of Sexual Organs in East Greenland Polar Bears (Ursus maritimus)." Environmental Science & Technology

Related Stories

New Report Shows Decline In Dioxin In Some U.S. Meat And Poultry (Aug. 21, 2006) — Levels of dioxin-like compounds (DLCs) appear to have declined in chickens, hogs and turkeys produced for food in the United States, according to new tests conducted by the U.S. Department of ...  > read more

Grizzlies And Salmon: Too Much Of A Good Thing? (Aug. 9, 2005) — Even grizzly bears should watch what they eat. It turns out that grizzlies that gorge themselves on salmon during the summer spawning season have much higher levels of contaminants in their bodies ...  > read more

Killer Whales Metabolize Contaminants, Yet Still Show Record-High Contamination Levels (Jul. 23, 2007) — Killer whales hold the gloomy record of being the most-polluted European arctic mammal, says a new study published in the latest issue of Environmental Toxicology and Chemistry. Levels of ...  > read more

Polar Bears Threatened By Hunting Policy Favoring The Killing Of Male Bears (Nov. 25, 2007) — Policies that encourage hunters to go after male polar bears in order to conserve females, could make it harder for the animals to find mates. Researchers determined there is a critical threshold in ...  > read more

Search ScienceDaily

Forest Robot Fleet