The study, conducted by researchers at Arizona State University, included 55 children with autism between the ages of 5-16 years as well as 44 controls of similar age and gender.
The findings showed that those in the autism group had much higher levels of lead in their red blood cells and significantly higher urinary levels of lead, thallium, tin, and tungsten.
The researchers conducted a statistical analysis to determine if the levels of toxic metals were linked to autism severity, using three different scales of autism severity.
They found that 38-47 percent of the variation of autism severity was associated with the level of several toxic metals, with cadmium and mercury being the most strongly linked.
In the report, the authors said, “We hypothesize that reducing early exposure to toxic metals may help ameliorate symptoms of autism, and treatment to remove toxic metals may reduce symptoms of autism; these hypotheses need further exploration, as there is a growing body of research to support it.”
The study was led by James Adams, Ph.D., a President’s Professor in the School for Engineering of Matter, Transport and Energy. He also directs the ASU Autism/Asperger’s Research Program.