New research claims that the practice of stubble burning may have been a key driver of Delhi’s third wave of COVID-19 infections.
The study, published in Urban Climate, identified a tenfold increase in the national capital during the biomass burning season which sees agricultural workers in the neighbouring states of Haryana and Punjab burn the straw stubble left after the winter harvest. The annual practice has long been identified as a driver of catastrophic levels of air pollution in the national capital, which has become so severe in recent years that the city has been likened to a gas chamber.
Using data from the System of Air Quality and Weather Forecasting And Research (SAFAR), a Ministry of Earth Sciences research project, researchers at the Indian Institute of Tropical Meteorology (IITM) found a correlation between the spread of COVID-19 in the national capital’s third wave and the stubble burning period. One of the study’s authors Gufran Beig told The Print “we hypothesise that the third COVID peak in Delhi was linked to the increase in pollution levels due to stubble burning in Punjab and Haryana.”
The study flags black carbon (BC), a pollutant generated by the burning of fuels such as biomass and fossils, as a risk factor. “We…report that the crop residue burning induced lethal aged black carbon-rich particles which engulfs Delhi during the post-monsoon months of October–November are strongly associated with COVID-19 and largely responsible for the sudden surge,” the researchers write. “It is found that the virus efficacy is not necessarily related to any particulates but it is more of source-based toxicity of its component where the virus is piggybacking.
“We conclude that the aged biomass BC particles tend to aggregate and react with other compounds to grow in size, providing temporary habitat to viruses leading to the rapid increase in COVID-19 cases which declined after the crop burning stopped.”
The problem of stubble burning was flagged last year as Delhi weathered yet another pollution crisis. As Health Issues India reported at the time, “the number of incidents of stubble-burning reportedly hit their peak between November 4th and November 7th this season. According to the Ministry of Earth Sciences’ air quality monitor, SAFAR, the share of stubble-burning in Delhi-NCR [National Capital Region]’s pollution peaked to 42 percent on November 5, when 4,135 farm fires were recorded in the region.
“This timeframe coincides with research that showed the Air Quality Index (AQI) – which measures the level of pollutants – exceeding 1,300 in Sukhdev Vihar earlier this month. This made it over thirty times the safe level set by the World Health Organization, and with the impact of air pollution on COVID-19 now well-documented as public health experts reports indicate a strong correlation, the city which is home to approximately thirty million people has a clear challenge.”
The onset of COVID-19 in India actually resulted in a reduction in air pollution, due to a reduction in economic and industrial activity. However, the subsequent reopening of the economy and resumption of industrial activity has seen air pollution levels rise. Even during so-called ‘lockdown 2.0’, pollution did not reduce. Delhi bore the brunt of poor air quality, seeing a 125 percent jump in NO2 levels and being assessed as having the worst breathable air out of eight state capitals.
“The air quality levels in these cities are alarming,” said Avinash Chanchal, senior climate campaigner at Greenpeace India in remarks to India Today. “People saw clean skies and breathed fresh air during the nationwide lockdown though it was an unintended consequence of the pandemic. The disruption caused by the COVID-19 pandemic is a case to transition to cleaner, equitable and sustainable decentralised energy sources.”
The latest findings from IITM adds further impetus to cracking down on air pollution and addressing its causes such as stubble burning. Yet this will not be easy. As BBC News noted last year, “governments have tried to stop the practice. They’ve pitched alternatives, they’ve banned it, they’ve fined farmers for continuing to do it and they’ve even thrown a few of them in jail. They’ve also tried to reward good behaviour – in 2019, the Supreme Court ordered a clutch of northern states to give 2,400 rupees ($32; £24) per acre to every farmer who didn’t burn stubble.” However, many of these strategies failed for reasons such as lack of funds for enforcement.
The solutions may lie in an agricultural rethink, some experts argue. The BBC News report quoted Dr Ashok Gulati, an agricultural economist, who said “the behaviour of farmers depends on the policies you put into place. Things like free electricity and cheap fertilisers are causing havoc.” Many farmers simply cannot afford to not burn stubble, as technologies designed to deal with the problem in environmentally friendly means are prohibitively expensive to operate. Instead, Gulati suggests, we should reorient towards subsidising the farming of other crops than paddy which is what drives the stubble burning problem. “Policy and money should incentivise farmers in the region to plant more fruits and vegetables,” he said. “India needs more vitamins and protein rather than wheat and rice.”
“Impact of biomass induced black carbon particles in cascading COVID-19” can be accessed here.