Beijing, November 6 Exposure to sources of outdoor pollution, such as exhaustion of vehicles and industrial emissions, may increase the risk of the child developing an autistic spectrum disorder up to 78%, warned a study.
Research has followed children in Shanghai from birth to three years to understand the effect of exposure to fine particles (PM2.5).
The study included 124 children of ASD and 1,240 healthy children in stages for a period of nine years, examining the association between atmospheric pollution and ASD.
The study, published in the journal Environment International, is the first to examine the effects of long-term exposure to atmospheric pollution on ASD during children's lives in a developing country, adding previous studies that already link antenatal exposure to atmospheric pollution in ASD in children
"The causes of autism are complex and do not fully understand, but environmental factors are increasingly recognized in addition to genetic factors and others," said Zhiling Guo of the Chinese Academy of Sciences.
"The developing brains of young children are more vulnerable to toxic exposures in the environment and several studies have suggested that this could affect brain function and the immune system," said Guo.
"These effects could explain the strong bond we find between exposure to atmospheric pollutants and ASD, but we must investigate more closely the associations between air pollution and mental health," he said.
Air pollution is a major public concern and it is estimated that it causes up to 4.2 million deaths (WHO) every year worldwide. External pollutants contribute to a high burden of disease and death prematurely in countries such as China and India, especially in densely populated areas.
According to Associate Professor, Yuming Guo of the University of Monash in Australia, global air pollution is rapidly worsening and there is no safe level of exposure.
"The serious effects on the health of atmospheric pollution are well documented, which suggests there is no safe level of exposure. Even exposure to very small amounts of fine particles has been linked to premature delivery, late learning and a series of serious conditions of health, including heart disease, "said Guo.
The study examined the health effects of three types of particulate matter (PM1, PM2.5, PM10) – fine particles in the air that are by-products of factory emissions, vehicular contamination, construction activities and road dust.
The smaller the particles in the air, the more able to penetrate the lungs and enter the blood produce a series of serious health conditions.
PM1 is the smallest in particle size, but few studies have been conducted on PM1 globally and agencies are still establishing security standards for this. MHN