evidence: No, vaccines do not cause autism. This damaging claim became a controversial issue in 1998, when a paper published in the journal The Lancet suggested that childhood vaccination was linked to autism. The claim subsequently fueled fears among some parents and resulted in widespread misinformation about vaccines. Some people claimed that vaccines caused autism because vaccines contained thimerosal, a mercury-containing antimicrobial and preservative. However, extensive studies exploring the proposed association have since found no scientific evidence to support a causal relationship between childhood vaccination and autism. Moreover, later analysis of the original 1998 paper revealed that the authors had made false claims and had violated research ethics, leading to its retraction in 2010. Although concerns about vaccines and autism have no scientific basis, health officials have gone to great lengths to allay public fears. In particular, as a precautionary measure in the United States, though the low doses of thimerosal used in vaccines are safe for humans, as of 2001 the substance is no longer used in childhood vaccines.