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.

Related Articles


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 25, 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 25, 2014).

Share This



More Plants & Animals News

Saturday, October 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Reuters - Innovations Video Online (Oct. 24, 2014) Miniature deep sea animals discovered off the Australian coast almost three decades ago are puzzling scientists, who say the organisms have proved impossible to categorise. Academics at the Natural History of Denmark have appealed to the world scientific community for help, saying that further information on Dendrogramma enigmatica and Dendrogramma discoides could answer key evolutionary questions. Jim Drury has more. Video provided by Reuters
Powered by NewsLook.com
Black Bear Cub Goes Sunday Shopping

Black Bear Cub Goes Sunday Shopping

Reuters - Light News Video Online (Oct. 23, 2014) Price check on honey? Bear cub startles Oregon drugstore shoppers. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Dances With Wolves in China's Wild West

Dances With Wolves in China's Wild West

AFP (Oct. 23, 2014) One man is on a mission to boost the population of wolves in China's violence-wracked far west. The animal - symbol of the Uighur minority there - is under threat with a massive human resettlement program in the region. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com
Breakfast Debate: To Eat Or Not To Eat?

Breakfast Debate: To Eat Or Not To Eat?

Newsy (Oct. 23, 2014) Conflicting studies published in the same week re-ignited the debate over whether we should be eating breakfast. Video provided by Newsy
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