Autism and Lead Poisoning Update

I commented on possible connections between autism and lead poisoning on October 13, 2007 in Autism and Lead Poisoning. I had referenced articles which discussed a lead/autism connection in some cases. I also included the following excerpt from the Ontario Environment Ministry page Lead and Drinking Water - Questions and Answers which discusses the impact of lead poisoning on learning capacity and intellectual development:

How does lead in water affect health? Young children are more sensitive to the effects of lead because they are still developing and able to absorb ingested lead more easily than adults. Long-term exposure to lead above the standards may increase the risk of subtle impairment of learning capacity and intellectual development. Pregnant women need to limit their lead intake as much as possible to protect the fetus.

Also highlighted in that comment was the article Autism and Autistic Symptoms Associated with Childhood Lead Poisoning, Journal of Applied Research, authors Theodore I. Lidsky, PhD , Department of Psychobiology, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York and Jay S. Schneider, PhD Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University College of Medicine, Philadelphia, Pennsylvania. That article featured two case studies of children who, during periods of severe lead poisoning, developed autism or autistic symptoms.

I mention a possible lead/autism connection again at this time because of news of yet another recall of lead contaminated toys and the announcement by Health Canada that it is sponsoring a pilot study aimed at measuring the long-term accumulation of lead in people's bones, something that cannot be determined by more commonly used blood tests, but that still poses a potential health risk. The National Post, author Tom Blackwell, has a good article on the announcement Recall of toys sparks study on lead risks and some related articles in the sidebar of the article page.

The NP article also includes criticism of Health Canada's lead investigation effort by lead safety advocate Kelly O'Grady who argues that HC should sponsor studies that focus on the most vulnerable - children under six years of age:

"It's kind of bizarre," said Ms. O'Grady, head of the group The First Six Years. "Health Canada is going in all the back doors, instead of looking at the elephant in the living room."

Mr. Blackwell also reports that:

Just in the past two weeks, the regulator [ Health Canada] publicized recalls of 35,000 plastic charm bracelets, 2,200 necklaces, 770 pendants and 575 sets of doll clothing, all imported from East Asia and all containing lead above the allowable limit. Such items are considered a danger to smaller children who might put them in their mouths.

Whether lead exposure is a causal agent in autism causes or simply causes "autistic like symptoms" and impairs learning capacity and intellectual development it is long past time that Health Canada and other public health authorities began to make a more sustained effort on two fronts. One, to immediately and thoroughly work at eliminating exposure to lead poisoning, particularly amongst children and pregnant women and two, began more thorough research into the role of lead and other environmental toxins into the development of autism and other neurological disorders. As Lidsky and Schneider concluded in their study:

The two case histories presented here, as well as the reports of autistic symptoms in children with disorders that produce brain lesions or encephalopa- thy, indicate that there are multiple causes of autism. Further, the ability of brain infections and lead poisoning to produce such symptoms highlights the importance of environmental factors in the etiology of *autism*.

The ability of *lead* *poisoning* to induce symptoms of *autism* is also relevant to cases of preexisting pervasive developmental disorders irrespective of etiology. Such individuals have a greater propensity to engage in pica and, as a result, are more likely to become *lead* poisoned.

In such cases, *lead* poisoning can be expected not only to negatively impact neurocognitive functioning, but also to potentially exacerbate the preexisting symptoms of *autism*

autism