An Australian study has pointed out that traffic pollution, particularly in urban areas, exacerbates asthma in children.
The study, conducted by University of Western Australia epidemiologist Gavin Pereira, showed how traffic pollution was a major factor in the 'worsening of the respiratory condition' in children, reports News.com.au.
"This study was conducted in Perth, Western Australia ... pollution levels are generally quite good in Perth," Pereira said.
There were other troubling implications, he said, as Australia had far more traffic-intensive cities than Perth and the effect was seen even as air quality was deemed to meet safety benchmarks.
Researchers assessed the cases of more than 600 children and adolescents who between 2002 and 2006 were rushed to West Australian hospitals suffering a serious asthma attack.
Air-quality records for the period leading up to each attack were checked, and this revealed a strong trend of rising traffic-related pollutants ahead of each hospital trip.
Atmospheric levels of nitrogen dioxide and carbon monoxide were often elevated on the day before a child suffered the asthma attack.
The effect was most pronounced in asthmatic children aged four and under, according to the research.
Pereira said he hoped the finding would stimulate more research into this area, and it was too early to suggest parents of asthmatic children consider moving to areas with less traffic.
"It's not a cause for panic among parents, but policy-setters should be incorporating these sorts of factors into their decisions. For parents, traffic pollution is ubiquitous in an urban environment - it is essentially unavoidable," he said.
"The message should go to our planners who might be building childcare centres and schools alongside roads, and children exercising by the street all the time," he added.
The research is published in the latest edition of the Medical Journal of Australia.