Mercury-Autism Study in Quebec

The mercury-based preservative thimerosol is NOT the cause of Autism. At least that's the conclusion of a soon-to-be-published study done in Quebec.

According to a report by The Edmonton Journal, the study will be published in the journal Pediatrics next month. The study is significant because Quebec began using only vaccines without thimerosal in 1996. So children raised in Quebec and under the age of ten have never been given a vaccine with the mercury-based preservative in it.

The Quebec study actually shows that the incidence of autism has been higher in the years since the use of thimerosol as a preservative was stopped. Of course, the incidence of autism has increased everywhere in the last decade, making Quebec relatively normal in that trend.

The relationship between thimerosol, autism, and childhood vaccines is complicated and confusing. Much of the current buzz began in 1998 when a study published in the British medical journal The Lancet suggested a possible link between the Measles-Mumps-Rubella (MMR) vaccine and autism. The study was not intended to examine that relationship (it was looking for a connection between viral infections and intestinal disease in children, and at the possibility that such intestinal diseases could contribute to the development of autism), included only 12 participants in the study, and has since had its validity questioned by many of the original researchers involved.

Another British study published in 2002 also suggested a link between measles (the disease, but not necessarily the vaccine), intestinal disease, and autism. The study was designed in a manner that prevented the researchers from determining whether either measles or intestinal disease actually caused autism. That study had only 161 participants. The Lancet published a study in 2004 with almost 6,000 participants; the study concluded that the MMR vaccine itself did not represent an increased risk for either autism or other disorders under the umbrella of autism spectrum.

To add to the confusion, the Centers for Disease Control says that while the preservative has been used in a number of other childhood vaccines in the past, the MMR vaccine has never contained thimerosal.

The cause (or causes) for the rising numbers of autism cases is among the most controversial issues in both medicine and education today.