The researchers found no differences in the mercury levels of children who were typically developing and the children with autism and autism spectrum disorders. This held true after accounting for fish intake, the biggest source of mercury exposure in the U.S., and continued to hold for children who did not eat fish. In addition, they found that the mercury levels in children with autism or autism spectrum disorders were similar to a nationally representative sample of U.S. children aged 1-5 years. The researchers do note that this study could not account for possible effects of maternal mercury exposure while pregnant or immediately after pregnancy. [19]