A man rides a bicylce in the outskirts of Colombo, where smog has been visible during the early hours of
the day. (AFP File Photo)
According to the World Health Organisation air pollution kills an estimated seven million people worldwide every year. To put things in perspective, that’s one third of Sri Lanka’s total population. The World Health Organisation (WHO) data also shows that nine out of ten people breathe air that exceeds its guideline limits, meaning that the majority of people around the world breathe air containing high levels of pollutants. It comes as no surprise that low- and middle-income countries are suffering from the highest exposures to air pollution. But what does this mean in the current Coronavirus climate the world is grappling with?
"The numbers are an estimate of only a fraction of COVID-19 deaths that could be avoided if people were exposed to less air pollution"
Long-term exposure to air pollution has been linked to an increased risk of death from COVID-19, a new study has found. The study published in the journal Cardiovascular Research analysed health and disease data related to air pollution, COVID-19 and SARS, from China and the United States.
The study combined this data together with data on global exposure levels to particulate matter, in order to measure the extent to which air pollution is linked to Covid-19.
The German and Cypriot experts involved in the study found that in East Asia, including China, 27 per cent of COVID-19 deaths can be linked to air pollution. In North America this number was at 17 per cent while in Europe 19 per cent of COVID-19 deaths could be attributed to poor air quality.
The team of researchers said that these numbers are an estimate of “the fraction of COVID-19 deaths that could be avoided if the population were exposed to lower counter factual air pollution levels without fossil fuel-related and other anthropogenic [caused by humans] emissions”.
"In Sri Lanka the levels of particulate matter in the air more than doubled during the month of October, according to NBRO"
“Attributable fraction does not imply a direct cause-effect relationship between air pollution and COVID-19 mortality (although it is possible). Instead it refers to relationships between two, direct and indirect,” the authors explained.
The researchers used epidemiological data from previous US and Chinese studies of air pollution and COVID-19 and the SARS outbreak in 2003, supported by additional data from Italy. They combined this with satellite data showing global exposure to polluting fine particles known as ‘particulate matter’ that are less than or equal to 2.5 microns in diameter (known as PM2.5).
"In the UK, 14% of the deaths have been attributed to air pollution. In the US the number was at 18%"
“Since the numbers of deaths from COVID-19 are increasing all the time, it’s not possible to give exact or final numbers of COVID-19 deaths per country that can be attributed to air pollution. However, as an example, in the UK there have been over 44,000 Coronavirus deaths and we estimate that the fraction attributable to air pollution is 14%, meaning that more than 6,100 deaths could be attributed to air pollution. In the USA, more than 220,000 COVID deaths with a fraction of 18% yields about 40,000 deaths attributable to air pollution.” Co-author of the
study Prof. Jos Lelieveld said.
Co-author Prof. Münzel explaining the health effects of air pollution said: “When people inhale polluted air, the very small polluting particles, the PM2.5, migrate from the lungs to the blood and blood vessels, causing inflammation and severe oxidative stress, which is an imbalance between free radicals and oxidants in the body that normally repair damage caused to cells”
"Researchers used epidemiological data from US & China and data from previous SARS outbreak in 2003"
This causes damage to the inner lining of arteries, the endothelium, and leads to the narrowing and stiffening of the arteries. The COVID-19 virus also enters the body via the lungs, causing similar damage to blood vessels, and it is now considered to be an endothelial disease. Prof. Münzel added: “If both long-term exposure to air pollution and infection with the COVID-19 virus come together, then we have an additive adverse effect on health, particularly with respect to the heart and blood vessels, which leads to greater vulnerability and less resilience to COVID-19,” the researchers explained.
Unexpected increase in air pollutants in October
According to data from the National Building Research Organisation’s Air Quality Monitoring Centres, air pollution levels in Sri Lanka had been on the rise several weeks ago. Apart from the Southern parts of Sri Lanka, the particulate matter level in the atmosphere in Colombo, Kandy, Puttalam, Vavuniya, Jaffna and other places has increased abnormally since October 27.
The amount of ‘particulate matter’ in the atmosphere has more than doubled in last few days with respect to the levels recorded in the past few weeks. According to the U.S. Air Quality Index, the smallest particulate material, PM 2.5, has a value of between 100 and 150, a condition that can have a profound effect on sensitive groups.
The air pollution levels had been low in urban areas of Sri Lanka since the onset of the pandemic owing to relatively low vehicular movements and emission. The NBRO attributed the variations of the wind patterns around the island as a possible cause of this sudden increase of air pollution. Based on the world air quality distribution map published in Air Visual website, the air pollutants levels of the atmosphere in the Indian peninsular is high during this time of the year and it would be a contributing factor to the Sri Lankan situation, they said in a recent statement.