Tiny particles in air pollution which includes diesel engine fumes 'double the risk of autism in unborn babies'

Women exposed to polluted air containing diesel fumes in late pregnancy could double their risk of having a child with autism, warn researchers.

They found the risk rises sharply in areas with high levels of traffic pollution, with women most vulnerable during the last three months of pregnancy.

An estimated 600,000 children and adults in the UK have autistic spectrum disorder, which restricts their ability to interact socially and communicate.

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Environmental health: The study, from the Harvard School of Public Health in Massachusetts, looked at the impact of exposure to PM2.5s, the small and very fine pollution particles produced by diesel engines

Genes play a role in its development but the impact of environmental factors is less clear, although previous studies suggest traffic pollution may play a part. 

The latest study, from the Harvard School of Public Health in Massachusetts, looked at the impact of exposure to PM2.5s, the small and very fine pollution particles produced by diesel engines. 

The study included children of participants taking part in the Nurses’ Health Study II, which involves 116,000 women US nurses.