Using data reported to the California Department of Development Services from 1995 to 2007, researchers from the California Department of Health compared the prevalence of autism with exposure to Thimerosal. Their results were published this week in the Archives of General Psychiatry (Jan. 2008). The data showed that the prevalence of autism for children at each year from 3 to 12 years increased throughout the study period — even after 2000 when Thimerosal began disappearing from vaccines. From 1999 to 2004, average exposure to Thimerosal among infants and 2-year olds was reduced by more than 90 percent and 84 percent, respectively — yet reported cases of autism continued to increase in unabated fashion.
A classic test in epidemiological study is to observe what happens to the rate of disease when the suspected agent is removed. When Thimerosal was removed, the rate of disease was unaffected. Thus the research continues to add to the body of knowledge that Thimerosal does not cause Autism. Use of Thimerosal in vaccines began in the 1930s in response to tragedies such as the January 1928 deaths of 11 of 21 children given a diphtheria vaccine inadvertently contaminated with staphylococci. Since that time, Thimerosal has been used to improve the safety of vaccines. Recently, however, Thimerosal has been or is being removed from vaccines.
NY Times Article
http://archpsyc.ama-assn.org/cgi/content/short/65/1/15 (abstract of paper)