Mercury has been linked to the development of autism. Researchers at the University of California, Davis studied 452 children between the ages of 2 and 5, 249 of whom had been diagnosed with autism. The children's blood mercury levels were measured and the researchers also attempted to find out where the mercury had come from. The study found that levels of mercury in the bloodstream were actually lower in the children with autism. This was because the main source of mercury was found to be fish which the autistic children - who are known to be picky eaters - ate less of. Once the data had been adjusted for fish consumption mercury levels in autistic and non-autistic children were found to be similar. Other sources of mercury were fillings and chewing gum but vaccinations (which can contain mercury as one of the ingredients) were not found to raise mercury levels.
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