Autism is a neurodevelopmental disorder with genetic and environmental influences. It has increased dramatically in incidence over the past 25 years. A newly published study conducted by researchers at the University of Texas Health Science Center in San Antonio explored the link between industrial release of mercury and increased autism rates. Data documenting mercury release were from 39 coal-fired power plants and 56 industrial facilities in Texas. Autism rates were examined from 1,040 Texas school districts.

For every 1,000 pounds of mercury released by all industrial sources into the environment in Texas in 1998, there was a corresponding 2.6% increase in autism rates in the Texas school districts in 2002. For every 1,000 pounds of mercury released by Texas power plants in 1998, there was a corresponding 3.7% increase in autism rates in Texas school districts in 2002. The researchers found that autism prevalence is reduced by 1-2% with each 10 miles of distance from a pollution source.

The United States Environmental Protection Agency estimated annual environmental mercury releases to be 158 million tons nationwide in the late 1990s. Dr. Palmer, one of the investigators, said, "We need to be concerned about global mercury emissions since a substantial proportion of mercury releases are spread around the world by long-range air and ocean currents. Steps for controlling and eliminating mercury pollution on a worldwide basis may be advantageous."

These new findings are similar to a number of other studies that confirm the presence of higher amounts of bodily incorporation of mercury in plant species, animals and humans the closer they are to the pollution source. The authors noted, "We suspect low-dose exposures to various environmental toxicants, including mercury, that occur during critical windows of neural development among genetically susceptible children may increase the risk for developmental disorders such as autism." There is additional evidence from unrelated studies that children and other developing organisms are more susceptible to the neurobiological effects of mercury exposure.