Featured Research

from universities, journals, and other organizations

Toxic Algal Blooms May Cause Seizures In California Sea Lions

Date:
June 10, 2008
Source:
National Oceanic And Atmospheric Administration
Summary:
An increase of epileptic seizures and behavioral abnormalities in California sea lions can result from low-dose exposure to domoic acid from toxic algal blooms as a fetus. This brain disturbance is a newly recognized chronic disease.

Baby California sea lion peeking out from a pile of adult sea lions. An increase of epileptic seizures and behavioral abnormalities in California sea lions can result from low-dose exposure to domoic acid from toxic algal blooms as a fetus.
Credit: iStockphoto/David Gomez

Scientists, reporting in the current issue of the online journal Marine Drugs, state that an increase of epileptic seizures and behavioral abnormalities in California sea lions can result from low-dose exposure to domoic acid as a fetus. The findings follow an analysis earlier this year led by Frances Gulland of the California Marine Mammal Center that showed this brain disturbance to be a newly recognized chronic disease.

John Ramsdell of NOAA's Center for Environmental Health and Biomolecular Research in Charleston, SC, in partnership with Tanja Zabka, a veterinary pathologist at the Marine Mammal Center, conducted the first-of-its kind analysis of poisoning by the algal toxin, domoic acid, during fetal brain development. The results, analyzed across multiple animal species, point to the toxin as a cause for behavioral changes and epilepsy that does not become evident until later in life.

Domoic acid is produced by harmful algal blooms. The algae is consumed by fish such as sardines, herring and anchovies, a significant part of the sea lion diet. Exposure during pregnancy concentrates the domoic acid toxin in the mother's amniotic fluid, which normally protects and aids in the growth of a fetus. In sea lions exposed to domoic acid, the fluid retains the toxin, thus subjecting the fetus to repeated direct absorption through immature skin cells and swallowing during gestation.

The results, demonstrated experimentally in laboratory animals and projected to occur in fetal sea lions, is abnormal development of brain neurons which does not impact the animal until it enters later life stages. This phenomenon, known as "fetal basis to adult disease," is expressed through seizures and abnormal behavioral changes.

"This represents a significant break through in understanding the origins of this behavior and will help us better understand the long-term consequences of exposure to harmful algal blooms during pregnancy," notes Ramsdell.

Algal blooms have been increasing in the sea lions' habitat, resulting in more cases of acute poisoning and increased concern over the long-term effects of algal toxins.

Scientists in NOAA's Oceans and Human Health Initiative are studying the impact of harmful algal blooms on marine mammals to determine if similar impacts could affect humans exposed to the similar harmful toxins.


Story Source:

The above story is based on materials provided by National Oceanic And Atmospheric Administration. Note: Materials may be edited for content and length.


Journal Reference:

  1. Ramsdell et al. In Utero Domoic Acid Toxicity: A Fetal Basis to Adult Disease in the California Sea Lion (Zalophus californianus). Marine Drugs, 2008; 6 (2): 262 DOI: 10.3390/md20080013

Cite This Page:

National Oceanic And Atmospheric Administration. "Toxic Algal Blooms May Cause Seizures In California Sea Lions." ScienceDaily. ScienceDaily, 10 June 2008. <www.sciencedaily.com/releases/2008/06/080609103232.htm>.
National Oceanic And Atmospheric Administration. (2008, June 10). Toxic Algal Blooms May Cause Seizures In California Sea Lions. ScienceDaily. Retrieved October 23, 2014 from www.sciencedaily.com/releases/2008/06/080609103232.htm
National Oceanic And Atmospheric Administration. "Toxic Algal Blooms May Cause Seizures In California Sea Lions." ScienceDaily. www.sciencedaily.com/releases/2008/06/080609103232.htm (accessed October 23, 2014).

Share This



More Plants & Animals News

Thursday, October 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Working Mother DIY: Pumpkin Pom-Pom

Working Mother DIY: Pumpkin Pom-Pom

Working Mother (Oct. 22, 2014) How to make a pumpkin pom-pom. Video provided by Working Mother
Powered by NewsLook.com
San Diego Zoo's White Rhinos Provide Hope for the Critically Endangered Species

San Diego Zoo's White Rhinos Provide Hope for the Critically Endangered Species

Reuters - Light News Video Online (Oct. 22, 2014) The pair of rare white northern rhinos bring hope for their species as only six remain in the world. Elly Park reports. Video provided by Reuters
Powered by NewsLook.com
Raw: Bear Cub Strolls Through Oregon Drug Store

Raw: Bear Cub Strolls Through Oregon Drug Store

AP (Oct. 22, 2014) Shoppers at an Oregon drug store were surprised by a bear cub scurrying down the aisles this past weekend. (Oct. 22) Video provided by AP
Powered by NewsLook.com
Family Pleads for Pet Pig to Stay at Home

Family Pleads for Pet Pig to Stay at Home

AP (Oct. 22, 2014) The Johnson family lost their battle with the Chesterfield County, Virginia Planning Commission to allow Tucker, their pet pig, to stay in their home, but refuse to let the board keep Tucker away. (Oct. 22) Video provided by AP
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