New Delhi: Road travel in Delhi can expose people to black carbon levels that are five times higher than in Europe and America, say researchers from the University of Surrey in the UK. Black carbon is produced by carbon-rich fuels such as gasoline and diesel fuel. The scientists also found that Asian residents are exposed to nine times more air pollution than their Western counterparts.
According to the World Health Organisation (WHO), 88% of premature deaths in low- and middle-income countries in Asia can be attributed to air pollution. While the number of vehicles in Beijing increased from 1.5 million in 2000 to more than 5 million in 2014, the numbers in Delhi are expected to increase from 4.7 million in 2010 to 25.6 million by 2030.
In a study published in the journal Atmospheric Environment, researchers looked at studies of pollution exposure and concentration levels in Asian transport micro-environments (walking, driving, cycling, motorbike riding and bus riding). They focused on the levels of fine particles, such as black carbon, and ultrafine particles (UFP) that are small enough to travel deep into a citizen’s lungs.
Alarmingly, the study found evidence that pedestrians walking along busy roadsides in Asian cities are exposed to up to 1.6 times higher fine particle levels than people in European and American cities. Car drivers in Asia are also exposed to up to nine times more pollution than Europeans and Americans, while black carbon levels were seven times higher for Asian pedestrians than Americans.
The study reported that in Hong Kong, UFP levels were up to four times higher than in cities in Europe. In New Delhi, average black carbon concentration in cars was up to five times higher compared to Europe or North America.
“Care should be taken in directly comparing and contrasting the results of different studies due to varied amounts of information available on personal exposure in studied regions,” said Prashant Kumar, director of the Global Centre for Clean Air Research at the University of Surrey. However, there is compelling evidence that people travelling in urban areas in Asian cities are being exposed to a significantly higher level of air pollution.
“There are increasing efforts in Asia to install properly designed and calibrated portable monitoring systems to measure actual exposures, using the data to better understand why high exposures occur and how to prevent them,” said Chris Frey of North Carolina State University in the US.