Established Link Between ADHD Inuit Children and Mercury Exposure

0
5,475 views
Inuit children are at higher risk of ADHD

Pregnant women living in the northern communities have even more reason to avoid eating foods that could have a high mercury content, especially after a recent study revealed that there is a directly link between ADHD and Inuit kids who have been exposed to higher levels of mercury. The mercury is often found in beluga meat and ringed seal liver.

The Mercury Exposure Study

The Journal of Environmental Health Perspectives published the study[1] that showed mercury might lead to their children developing the set of behavioural problems known as Attention Deficit Hyperactivity Disorder, or ADHD.

This study was conducted by researchers at the Université Laval, Université de Sherbrooke, Wayne State University School of Medicine, and Centre Hospitalier Universitaire de Québec. The study is the first to discover a link between mercury detected in prenatal cord blood and childhood ADHD symptoms. It is also the first study to duplicate formerly reported associations between ADHD and low-level childhood lead exposure primarily from dietary sources.

Children who suffer fro ADHD or Attention Deficit Hyperactivity Disorder tend to have violent outbursts and trouble controlling their actions. They cannot concentrate in school and often act out aggressively to their classmates and teachers.

“ADHD is the most frequent behavioral problem reported for children all over the world,” said Dr. Gina Muckle, a Laval University researcher and co-author of the Environmental Health Perspectives study on the link between ADHD and mercury. “And we know that the number of children with ADHD is increasing.”

20 Years of Research on the Inuit People

Dr. Muckle has spent the last 20 years studying the effects of toxins such as lead and mercury on the Inuit people. She has worked with local officials in an effort to reduce exposure and contamination. For example, Dr. Muckle worked with the Nunivak Regional Board of Health and Social Services to create a voluntary ban on the use of lead bullets. The result was a decrease in the lead levels in the blood of Nunivak people.

This recent study by Dr. Gina Muckle focused on children in Nunivak and what she found was high concentrations of mercury in the children’s blood right at birth. In fact, these newborn babies were born were four times more likely to develop behaviors associated with ADHD as school age children.

The study also examined children’s blood lead levels exposed after birth, through food hunted with lead pellets. Even those children with very low blood lead levels still had a higher evidence of ADHD behaviors. In contrast, some other toxins that were studied, included PCB exposures, post-natal methylmercury and pre-natal lead exposure, and did not appear to be significantly associated with ADHD symptoms.

No Boudaries for Mercury

What’s tough is that there are no boundaries for the use contaminants. So, food sources could become toxic thousands of miles away from where they are caught and eaten. This means until everyone comes on board the issue of contaminated food is going to remain a concern.

“The mercury that we find in the North is coming mostly from China and other developing countries that are burning coal for the production of energy,” said Muckle. “Emissions then travel through the air and reach the Arctic.”

The good news is that the United Nations Environment Programme is addressing mercury emission sin an ongoing mandate that focuses on reaching an agreement by 2013. This agreement would be between China, Canada, and the United States, as well as the Inuit Circumpolar Council.

In the past 30 years, domestic mercury emissions in Canada have dropped by 90 percent. However, over 40 percent of the current mercury deposits in Canada are coming from the burning of coal in other countries, especially China. In addition, because environmental contaminants have no boundaries they make their way into Canadian waters and soil, putting Canadians at risk, especially children.

Fifty years ago, ADHD was practically unheard of. Most people had no idea what ADHD was. Today, around the world, a whopping 10 percent of children have ADHD. It is common, and most people are aware of what ADHD is. Why is that? What have we done or what has changed that has resulted in such a drastic change in the number of affected children, not just in the Inuit, but all children.

Muckle says that children have always exhibited aggressive behavior, and researchers are examining whether the numbers are up because it is now being recorded more widely or because there are more real cases developing. The issue is serious no matter why the numbers are on the increase.

Muckle says, “Aggressive behavior may have helped an Inuit child two or three generations ago, she said, but it has no place in the modern world. It was different 60 years ago in the nomadic period where those children likely would have been successful in some ways,” said Muckle. “Now children must spend many hours a day a in school. This kind of environment puts children who are more aggressive and active in a difficult situation.”

So how can pregnant women protect their unborn children? One of the recommendations is for women of childbearing age and pregnant women to avoid eating beluga meat, which has the highest concentration of mercury. The other recommendation is to stop the use of lead bullets.

Link Between Mercury Exposure and ADHD

The link between mercury exposure and ADHD in Inuit children should bring the rest of the world to attention. Contamination of our food source is very real and it is affecting our children. The researchers note that findings such as these have clinical significance and this research may tie closely to other studies involving lead contamination.

It would appear that governments and officials need to begin to pay more attention to lead contamination and mercury contamination, not just in Inuit children, but also in children throughout the world. The ability for contaminated foods to travel thousands of miles makes it difficult for any one government to gain control of the situation. It will take a cooperative action by all governments and officials.
Sources:

1) Volume 120 Issue 10 October 2012 G. Muckle, Prenatal Methylmercury, Postnatal Lead Exposure, and Evidence of Attention Deficit/Hyperactivity Disorder among Inuit Children in Arctic Québec, October 1, 2012.