The second Covid-19 wave not only unleashed unprecedented devastation of human life but also some worst air pollution episodes in Delhi despite the lockdown during March-May 2021, a new study has revealed.
According to the study in journal ‘Chemosphere’ published by SAFAR, experts say that the biomass emissions of carbon rich tiny particles and rapid flow of distant dust were found to be primary reasons for the pollution.
The study also made some shocking revelations that an “unaccounted emission source” was playing a leading role after balancing of the impact of curtailed lockdown emissions.
“The hidden source of emission is believed to be associated with additional carbonaceous biofuel burning related to crematories whose emissions could not be accounted for in the model,” an excerpt of the research paper read.
The steep surge in infection counts and the peak mortality (400 deaths/day) period was directly coinciding with peak levels of PM2.5. The study modelled the emission as per the wood required for cremation (around 300-400 kg/pyre) for open pyre and accounted for the chemistry of crematoria flue gases which contain higher percentage of organic, inorganic matter and particulate dust material.
According to the study, the increased carbon rich PM2.5 and PM10, aggravated the severity of Covid patients and vulnerable population, further adding to the misery.
Researchers also found that other peaks in the later part of lockdown were related to the north-westerly winds which often brought dust particles from the desert region to Delhi. The frequency of such dust storms was unusually higher than normal, probably due to free and faster flow of dust without much resistance under this lockdown period.
The paper concluded that since both Covid-19 and the dust storms can cause overlapping respiratory symptoms, a suitable strategy needs to be worked out during such emergencies.
