Navigation Links
Mercury contamination found in stranded Victorian dolphins
Date:6/10/2008

Monash University research into heavy metal contaminant levels in dolphins from Port Phillip Bay and the Gippsland Lakes has revealed high mercury levels may be a contributing factor to dolphin deaths.

Researchers from the School of Biological Sciences have confirmed levels of mercury found in the dolphins were within a range considered to cause negative health and mental effects and were higher than mercury levels found in populations around the world.

Supervisory researcher Dr Ross Thompson said the mercury concentrations in 20 live and eight dolphins which died after becoming stranded, collected over the last two years, were measured by Honours student Alissa Monk. Levels in the dead dolphins averaged 3.45 milligrams of mercury per kilogram of tissue compared to 1.32 mg/kg in living dolphins.

"Mercury levels detected are sufficient to cause significant health impacts and were comparable to those found in areas of the world that are considered highly polluted, including the Mediterranean Sea," Dr Thompson said.

Mercury has been shown in previous national studies to bioaccumulate in dolphins, but this is the first study to find particularly high levels in stranded animals in coastal Victoria. Bioaccumulation is the food chain process whereby smaller fish containing mercury are eaten by larger mercury contaminated fish, which are then consumed by dolphins, who can consume up to ten kilograms of fish a day. Mercury levels found in fish were considered low (<0.5 mg/kg) and were fine for human consumption.

"Dolphins may be becoming stranded as a direct consequence of mercury contamination which damages their neurological system. They become potentially confused and disorientated, and strand themselves. Even the apparently healthy dolphins had high levels of mercury which put them at risk of future health complications," Dr Thompson said.

Dr Thompson said mercury is likely to have come from the sediments of the Bay and researchers are concerned that dredging activities may increase the dolphins' exposure.

"Sediment contains mercury, which is likely to have originated from historical gold mining sites where mercury was used in gold processing, as well as from other industrial sources. Over time, the mercury has been washed down through waterways, including the Yarra River, and come to rest on the bottom of the Bay," Dr Thompson said.

Dr Thompson said it was critical that further studies were done throughout the bay dredging process to ensure any further decline in dolphin health could be identified and managed.


'/>"/>

Contact: Samantha Blair
samantha.blair@adm.monash.edu.au
61-399-034-840
Monash University
Source:Eurekalert

Related biology news :

1. Study shows mercury levels from products decreasing, though still at dangerous levels
2. Dental chair a possible source of neurotoxic mercury waste
3. Washington University, 2 industries, team to clean up mercury emissions
4. Dartmouth researchers alarmed by levels of mercury and arsenic in Chinese freshwater ecosystem
5. Waterborne carbon increases threat of environmental mercury
6. Groundbreaking Canada-US study proves link between emissions and mercury pollution in fish
7. International team shows mercury concentrations in fish respond quickly to increased deposition
8. New study shows fish respond quickly to changes in mercury deposition
9. New study shows fish respond quickly to changes in mercury deposition
10. Groundbreaking Canada-US study proves link between emissions and mercury pollution in fish
11. International team shows mercury concentrations in fish respond quickly to increased deposition
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/3/2016)... Feb. 3, 2016 ... of the "Emotion Detection and Recognition ... and Others), Software Tools (Facial Expression, Voice ... Users,and Regions - Global forecast to 2020" ... --> http://www.researchandmarkets.com/research/d8zjcd/emotion_detection ) has announced the ...
(Date:2/2/2016)... 2, 2016 Technology Enhancements Accelerate Growth of X-ray ... the digital and computed radiography markets in ... Indonesia (TIM). It provides an ... as well as regional market drivers and restraints. The ... penetration and market attractiveness, both for digital and computed ...
(Date:2/1/2016)... Feb. 1, 2016  Today, the first day of ... plans to develop a first of its kind workplace ... IBM Watson. In the first application of ... IBM ), and Welltok will create a new ... with cognitive analytics, delivered on Welltok,s health optimization platform. ...
Breaking Biology News(10 mins):
(Date:2/4/2016)... ... February 04, 2016 , ... Morf Media Inc ... an interactive FDA compliance training course, Writing Effective SOPs ... accredited interactive course on Morf Playbook—now conveniently available on smartphones and PCs--provides step ...
(Date:2/4/2016)... ... February 04, 2016 , ... Shimadzu Scientific Instruments ... host live demos and poster sessions, and present on the analysis of mycotoxins ... place March 6 to 10 at the Georgia World Congress Center in Atlanta, ...
(Date:2/4/2016)... , Feb. 4, 2016  CytoSorbents Corporation ... leader commercializing its flagship CytoSorb® blood filter to ... patients around the world, announced that CEO Dr. ... at the Source Capital Group,s 2016 Disruptive Growth ... on the company.  Conference Presentation ...
(Date:2/4/2016)... Feb. 4, 2016 ContraVir Pharmaceuticals, Inc. (NASDAQ: ... development and commercialization of targeted antiviral therapies, announced today ... Conference 2016, to be held February 8-9, 2016, at ... 2016 Disruptive Growth & Healthcare Conference, taking place in ... 2016. James Sapirstein , Chief Executive Officer ...
Breaking Biology Technology: