Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Mercury Levels and Cognitive Function Investigated in Adults

20.04.2005


Although the omega-3 fatty acids found in fish are well known for their health benefits, many fish are also the primary source of mercury in the general population. Researchers from the Johns Hopkins Bloomberg School of Public Health recently completed the first study of mercury and cognitive function in urban, U.S. adults between the ages of 50 and 70 years. They found that blood mercury levels were not consistently associated with adverse performance on a broad range of tests of cognitive function. This study may help policy makers with future decisions about mercury emissions from power plants as well as fish consumption recommendations for older adults. The study is published in the April 20, 2005, issue of the Journal of the American Medical Association (JAMA).



“Our study provides no evidence to challenge the government’s current recommendations for blood mercury levels, but neither does it indicate that they are safe. The key point is that the aging population may be more sensitive to toxic chemicals and this is the first study to examine mercury exposure in the older U.S. population,” said Megan Weil, MHS, lead author of the study and a PhD-candidate in the Bloomberg School of Public Health’s Department of Environmental Health Sciences.

Weil explained that the Environmental Protection Agency bases its recommendations on studies of children and women of childbearing age. From these studies, they determined that blood mercury levels should not exceed 5.8 µg/L. The median mercury level in study participants was 2.1 µg/L and only approximately 10 percent of subjects exceeded the government guideline.


The researchers analyzed the blood samples of 474 study participants, who were part of the larger Baltimore Memory Study. They also administered 12 cognitive function tests, which measured language, memory, attention, concentration, reaction time and other brain functions. The study authors found that higher blood mercury levels were associated with poorer performance on a memory test that measured the ability to recall a complex, two-dimensional line drawing. However, they saw improved performance on tests measuring motor speed, eye-hand coordination and manual dexterity. Because most of the large number of tests showed no correlation with mercury and there was a lack of consistency of mercury effects in the different aspects of brain function, the researchers concluded that overall the data did not provide strong evidence that mercury at these levels had an adverse impact on cognitive function.

“Mercury is a major global public health challenge. Global emissions will continue to increase for the foreseeable future and mercury released in one area can reach people at very great distances. Studies of this type are critical to the development of effective regulatory policies,” said Brian Schwartz, MD, senior author of the study and a professor in the Bloomberg School of Public Health’s Department of Environmental Health Sciences.

The study was supported by the National Institute of Environmental Health Sciences and the National Institute of Occupational Safety and Health.

Additional co-authors of the study were Joseph Bressler, PhD, Patrick Parsons, PhD, Karen Bolla, PhD, and Thomas Glass, PhD.

Public Affairs media contacts for the Johns Hopkins Bloomberg School of Public Health: Kenna Lowe or Tim Parsons at 410-955-6878 or paffairs@jhsph.edu.

Kenna Lowe | EurekAlert!
Further information:
http://www.jhsph.edu

More articles from Studies and Analyses:

nachricht New study from the University of Halle: How climate change alters plant growth
12.01.2018 | Martin-Luther-Universität Halle-Wittenberg

nachricht Disarray in the brain
18.12.2017 | Universität zu Lübeck

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

Im Focus: Room-temperature multiferroic thin films and their properties

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...

Im Focus: A thermometer for the oceans

Measurement of noble gases in Antarctic ice cores

The oceans are the largest global heat reservoir. As a result of man-made global warming, the temperature in the global climate system increases; around 90% of...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

World’s oldest known oxygen oasis discovered

18.01.2018 | Earth Sciences

Uncovering decades of questionable investments

18.01.2018 | Business and Finance

Novel chip-based gene expression tool analyzes RNA quickly and accurately

18.01.2018 | Medical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>