NEW DELHI: A study conducted by government agency System of Air Quality and Weather Forecasting And Research (SAFAR) has stated that particulate matter that is assumed as the harmful element in Delhi’s air is less harmful than thought.
Project director of SAFAR Gufran Beig revealed this from results of a study undertaken in December, 2016. According to a SAFAR analysis, in Delhi, around 7.6 per cent of the particulates are made of black carbon (BC). Sulphate (SO4) particles stand at around 7 per cent, the larger presence of which would have heightened the toxicity of Delhi’s air.
“The presence of toxic components may be less, but we have to keep in mind the sheer abundance of particulate matter in Delhi’s air. So the volume of particulates, which spikes periodically, may be negating the potential benefits of having less harmful chemical components,” said Beig.
The agency, which comes under the Ministry of Earth Sciences, has found that around 38 per cent of particulates are made of aluminium and silicon oxides, present in the earth’s crust but not as harmful as BC or SO4.
BC or SO4 act as aggravating factors when present beyond 15-20 per cent, Beig said. In fact, in Mumbai, where pollutants are less compared to Delhi, the percentage of BC is higher, he said.
The prescribed 24-hour-average of PM2.5 is 60 micrograms per cubic metre while the same is 100 in case of PM10.
“To assess the actual impact of pollution on an individual, factoring in the chemical characterisation of pollutants is crucial. One should not jump to conclusions purely based on figures of particulates captured by monitoring stations,” Beig said further. Delhi had experienced a severe episode of smog in November 2016 when fireworks during Diwali had pushed pollution to an alarming level.