A recent study led by the Heinz Endowments was conducted in Western Pennsylvania. The study researched a hypothesis according to which certain air pollutants may place a child at an increased risk for developing autism spectrum disorder (ASD). This specific region was chosen for the study as a consequence of the high number of cases reported in the area along with certain environmental factors being especially present.
The paper’s preliminary results have been accepted for review by the the American Association for Aerosol Research; it’s one of the first times researchers have found a correlation between air pollution and autism rates.
“Autism spectrum disorders are a major public health problem, and their prevalence has increased dramatically,” the study’s lead researcher Dr. Evelyn Talbott said in a press release. “Despite its serious social impact, the causes of autism are poorly understood. Very few studies of autism have included environmental exposures while taking into account other personal and behavioral risk factors. Our analysis is an addition to the small but growing body of research that considers air toxics as one of the risk factors for ASD.”
Dr. Talbott and her colleagues performed a population-based study of families with and without ASD living in six southwestern Pennsylvania counties. The researchers found links between increased levels of chromium and styrene and childhood autism spectrum disorder, a condition that affects one in 68 children. Dr. Talbott and her team interviewed 217 families of children with ASD and compared these findings with information from two separate sets of comparison families of children without ASD born during the same time period within the six-county area.
Children who fell into higher exposure groups of styrene and chromium were at a 1.4- to two-fold greater risk of ASD, after accounting for the age of the mother, maternal cigarette smoking, race and education. Styrene is used in plastics and paints and is a product of combustion from burning gasoline in vehicles. Air pollution containing chromium is typically the result of the industrial process from industries such as steel manufacturing.
Styrene is a compound often used in plastics and paints, and it is also produced by burning gasoline. Chromium is a heavy metal produced by steel hardening and other industrial processes, as well as power plants. Other air pollutants – including cyanide, methylene chloride, methanol and arsenic – were also linked to increased autism risk in children.