Bird feathers show pollution rise

2011-04-18 22:42

Washington - Feathers collected from rare Pacific sea birds over the past 120 years have shown an increase in a type of toxic mercury that likely comes from human pollution, US researchers said on Monday.

Scientists at Harvard University took samples from feathers belonging to the endangered black-footed albatross from two US museum collections, said the study in the Proceedings of the National Academy of Sciences.

The feathers, which dated from 1880 to 2002, showed "increasing levels of methyl mercury that were generally consistent with historical global and recent regional increases in anthropogenic mercury emissions," the study said.

Methylmercury is a neurotoxin that can cause central nervous system damage and comes from burning fossil fuels.

Rising levels of mercury in fish and seafood are believed to pose dangers to human health, and pregnant women and young children are particularly urged to limit the amount of some types of fish in their diets.

"Using these historic bird feathers, in a way, represents the memory of the ocean," said study co-author Michael Bank, a research associate in the Department of Environmental Health at Harvard School of Public Health.

"Our findings serve as a window to the historic and current conditions of the Pacific, a critical fishery for human populations," Bank said.

The highest concentrations in feathers were linked to exposure by the birds in the post-1990 time frame, which coincided with a recent spike in pollution from Asian carbon emissions in the Pacific region, the study said.

China the largest emitter

Mercury pollution from Asia went from about 700 tons annually in 1990 to 1 290 tons in 2005, the study said, noting that China became the largest emitter of such pollutants in 2005 with 635 tons.

Pre-1940 levels of mercury in bird feathers were the lowest in the study.

The black-footed albatross is listed as endangered by the International Union for Conservation of Nature, which estimates about 129 000 of them are living in the northern Pacific, mainly near Hawaii and Japan.

The birds feed primarily on fish, fish eggs, squid and crustaceans.

The high levels of mercury in their feathers could indicate a link between their high-mercury diets and their decreasing numbers, said the study.

"Given both the high levels of methyl mercury that we measured in our most recent samples and regional levels of emissions, mercury bio-accumulation and toxicity may undermine reproductive effort in this species and other long-lived, endangered sea birds," said lead author Anh-Thu Vo, a graduate student at the University of California, Berkeley.

Banks added that "mercury pollution and its subsequent chemical reactions in the environment may be important factors in species population declines".

Read more on:    china  |  environment  |  marine life

Join the conversation! encourages commentary submitted via MyNews24. Contributions of 200 words or more will be considered for publication.

We reserve editorial discretion to decide what will be published.
Read our comments policy for guidelines on contributions.

linking and moving

2015-04-22 07:36 publishes all comments posted on articles provided that they adhere to our Comments Policy. Should you wish to report a comment for editorial review, please do so by clicking the 'Report Comment' button to the right of each comment.

Comment on this story
1 comment
Comments have been closed for this article.

Inside News24


Book flights

Compare, Book, Fly

Traffic Alerts

The new moon is in Aquarius and it is a good time to begin a new project or start something new. Plant those innovative seeds more

There are new stories on the homepage. Click here to see them.


Create Profile

Creating your profile will enable you to submit photos and stories to get published on News24.

Please provide a username for your profile page:

This username must be unique, cannot be edited and will be used in the URL to your profile page across the entire network.


Location Settings

News24 allows you to edit the display of certain components based on a location. If you wish to personalise the page based on your preferences, please select a location for each component and click "Submit" in order for the changes to take affect.

Facebook Sign-In

Hi News addict,

Join the News24 Community to be involved in breaking the news.

Log in with Facebook to comment and personalise news, weather and listings.