Featured Research

from universities, journals, and other organizations

Killer Whales Metabolize Contaminants, Yet Still Show Record-High Contamination Levels

Date:
July 23, 2007
Source:
Allen Press
Summary:
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 contaminants measured in whales near Norway were among the highest ever measured in marine mammals, exceeding levels found in harbor seals, polar bears, and white whales.

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 contaminants measured in whales near Norway were among the highest ever measured in marine mammals, exceeding levels found in harbor seals, polar bears, and white whales.

Killer whales are widely distributed marine mammals capable of surviving on a variety of foods. In this study, blubber samples were taken, using a dart gun, from eight live, free-ranging whales. Contamination levels were six to 20 times higher in killer whales compared to other high-Arctic species, such as white whales.

Very high levels of halogenated organic contaminants (HOCs), including polychlorinated biphenyls (PCBs) and chlorinated pesticides were found in the tissues of killer whales, apparently due to their high concentration in the whales’ primary diet source, herring.

Despite the ban on most PCBs, toxaphene, and DDT, these compounds pose a continuing threat to the health of humans and marine organisms. New HOCs, such as the polybrominated diphenyl ethers (PBDEs) which are used as flame retardants, continue to be released into the environment.

Organisms are particularly vulnerable to HOCs in the marine environment. Because of the low water solubility of these compounds, exposure through the food web leads to the highest concentrations in marine mammals. Several studies have demonstrated adverse effects on the endocrine and immune systems of some marine mammals.

While most HOCs are considered to be poorly metabolized, killer whales in this study had lower levels of certain PCBs, pesticides (chlordane, DDE), toxaphene, and PBDEs than expected, suggesting an ability to metabolize them. This was unexpected, because other marine mammals, such as dolphins and white whales, show a much lower ability to metabolize HOCs.


Story Source:

The above story is based on materials provided by Allen Press. Note: Materials may be edited for content and length.


Cite This Page:

Allen Press. "Killer Whales Metabolize Contaminants, Yet Still Show Record-High Contamination Levels." ScienceDaily. ScienceDaily, 23 July 2007. <www.sciencedaily.com/releases/2007/07/070721223714.htm>.
Allen Press. (2007, July 23). Killer Whales Metabolize Contaminants, Yet Still Show Record-High Contamination Levels. ScienceDaily. Retrieved October 21, 2014 from www.sciencedaily.com/releases/2007/07/070721223714.htm
Allen Press. "Killer Whales Metabolize Contaminants, Yet Still Show Record-High Contamination Levels." ScienceDaily. www.sciencedaily.com/releases/2007/07/070721223714.htm (accessed October 21, 2014).

Share This



More Plants & Animals News

Tuesday, October 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

White Lion Cubs Born in Belgrade Zoo

White Lion Cubs Born in Belgrade Zoo

AFP (Oct. 20, 2014) Two white lion cubs, an extremely rare subspecies of the African lion, were recently born at Belgrade Zoo. They are being bottle fed by zoo keepers after they were rejected by their mother after birth. Duration: 00:42 Video provided by AFP
Powered by NewsLook.com
Traditional Farming Methods Gaining Ground in Mali

Traditional Farming Methods Gaining Ground in Mali

AFP (Oct. 20, 2014) He is leading a one man agricultural revolution in Mali - Oumar Diatabe uses traditional farming methods to get the most out of his land and is teaching others across the country how to do the same. Duration: 01:44 Video provided by AFP
Powered by NewsLook.com
Goliath Spider Will Give You Nightmares

Goliath Spider Will Give You Nightmares

Buzz60 (Oct. 20, 2014) An entomologist stumbled upon a South American Goliath Birdeater. With a name like that, you know it's a terrifying creepy crawler. Sean Dowling (@SeanDowlingTV) has the details. Video provided by Buzz60
Powered by NewsLook.com
Adorable Video of Baby Rhino and Lamb Friend Playing

Adorable Video of Baby Rhino and Lamb Friend Playing

Buzz60 (Oct. 20, 2014) Gertjie the Rhino and Lammie the Lamb are teaching the world about animal conservation and friendship. TC Newman (@PurpleTCNewman) has the adorable video! Video provided by Buzz60
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins