A study involving scientists from IIT Delhi and the Chittaranjan National Cancer Institute in Kolkata (CNCI) shows that around one in every four persons in the city and its peripheral urban areas suffers from ailments in upper respiratory areas like sneezing, coughing and runny nose.
As the year comes to a close on a smog-enveloped city, the combination of
viruses and surging PM 2.5 is taking a heavy toll, several environment experts told The Telegraph.
PM 2.5, the toxic ultra fine particulate pollutant, can enter the deepest crevices of the lungs and trigger a range of diseases.
On Christmas evening, a play in a hall in south Kolkata had an unplanned background noise — constant coughing of the spectators. Ditto in several public places.
“The study aimed to explore the effect of short and long-term exposure to PM 2.5 on upper and lower respiratory systems in the urban and rural population near Kolkata (Kolkata). A total of 1,155 people of varying ages were surveyed during 2020-22.… We found a strong association between health exposures and long-term exposure…” states the report — Health Effects of Short and Long-Term Air Pollution Exposure — prepared by environmental organisation Climate Trends involving scientists of IIT Delhi and the CNCI.
Air pollution experts of IIT Delhi, who are associated with the study, are being engaged by the West Bengal Pollution Control Board to analyse the air pollution in the state and suggest remedial actions.
“Overall, around one-fourth of the sampled people were found to be suffering from upper respiratory symptoms. The statistic is highest among teenagers, (31 per cent), followed by adults (25.5 per cent) and aged population (25 per cent),” said a researcher of the project.
“In Kolkata, upper respiratory symptoms were more than lower respiratory symptoms, which strongly suggests the impact of air pollutants. While sneezing was found in 45 per cent of the people surveyed, 30 per cent of the people were found with runny nose and coughing,” said Aarti Khosla, director of Climate Trends.
The report stated that “the air of all the survey locations seem to be highly polluted both in terms of long and short-term exposures”.
The Central Pollution Control Board’s data show that the city’s average PM 2.5 concentration rose to 91.7 micrograms between December 22 midnight and December 26 midnight this year.
The national day level standard of PM 2.5 is 60 micrograms, while the World Health Organisation’s standard is 15 micrograms.
“During this time of the year, the particulate level increases mainly due to the inversion phenomenon and hence the exposure becomes higher. These particulates often act as the carriers to several toxic elements, including the viruses that reach our system and trigger a series of respiratory problems,” explained Anumita Roy Chowdhury, an air pollution expert with the environment think tank Center for Science and Environment (CSE).
Dhrubajyoti Chatterjee, vice-chancellor of Sister Nivedita University and a scientist, said the virus load increases during winter, making matters worse.
“Many viruses are active during this season but particularly the rhinovirus, within a temperature range of 20 to 25 degrees Celsius, triggering common cold and associated respiratory problems,” said Chatterjee.