StudyNew Delhi, Dec 19 (PTI) Air-borne particles from the saltmines of Afghanistan are pushing up the levels of airpollutants in Delhi, a team of scientists has found.
Initially, the Central Pollution Control Board (CPCB)team had thought that the wind might be carrying sea salt fromeither the Bay of Bengal or the Arabian Sea. Subsequently, thesource of the pollutants was traced to Afghanistan.
A study by the CPCB scientists, including its airlaboratory chief Dipankar Saha, has found that about 11 percent of PM2.5 in Delhi are salt particles.
However, since the study was undertaken during the wintermonths, the scientists ruled out the possibility of theparticles being carried from the sea as the wind direction wasgenerally from the north or north-west during this period.
"We undertook a study, using the trajectory models of theUS government's National Oceanic and AtmosphericAdministration. That is when we found that the salt particleswere coming from those areas of Afghanistan, which have largesalt pans," Saha said.
The scientists also found the presence of metals such aschromium and copper in the city's air, which Saha said werebeing emitted by the electroplating industries in Haryana.
There were no safe standards for these metals yet, Sahasaid, adding that exposure to chromium could trigger healthcomplications.
PM2.5, which are essentially ultrafine particulates 30times finer than the human hair, are mainly composed ofsulphates, nitrates, ammonia, sodium chloride, black carbon,mineral dust and water, according to the World HealthOrganisation (WHO).
The study once again establishes the role of externalsources in the city's air being toxic.
Last month, the Centre-run pollution monitoring agency,SAFAR, had identified a West Asian dust-storm as the chieftrigger behind the recent smog episode in Delhi-NCR.
On November 8, the contribution of the dust-storm to thecity's air pollutants was 40 per cent, eclipsing the emissionsfrom stubble-burning, which stood at 25 per cent, the Pune-based System of Air Quality And Weather Forecasting andResearch (SAFAR) had said. PTI SBRRC.
This is unedited, unformatted feed from the Press Trust of India wire.