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An ecological study on childhood autism

Sophie St-Hilaire1*, Victor O Ezike2, Henrik Stryhn1 and Michael A Thomas2

Author Affiliations

1 Department of Health Management, Atlantic Veterinary College, University of Prince Edward Island, 550 University Avenue, Charlottetown, PE C1A 4P3, Canada

2 Department of Biological Sciences, Idaho State University, 921 S. 8th Ave, Pocatello, Idaho, 83209, USA

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International Journal of Health Geographics 2012, 11:44  doi:10.1186/1476-072X-11-44

Published: 11 October 2012


Background and methods

Idiopathic autism, suspected to be caused by exposure of genetically susceptible individuals to unknown environmental triggers, has increased dramatically in the past 25 years. The objectives of our study were to determine, using a linear regression model, whether the county prevalence of autism in the Pacific Northwest of the United States was associated with the source of drinking water for that county and whether this relationship was dependent on the level of environmental pollutants and meteorological factors in the county.


We found the previously reported relationship between precipitation and autism in a county was dependent on the amount of drinking water derived from surface sources in the county. We also found a positive association between the EPA’s risk of neurological disease and autism, but this relationship was only present in warm areas.


Our study provides evidence for the hypothesis that environmental factors are associated with autism and that meteorological factors play a role in this relationship.

Idiopathic autism; Environmental factors; Drinking water; Air pollutants; Precipitation