Urgent steps need to be taken to restore the purity of the air we breathe, in the best interests of our present and future generations. The apex court and the NGT are doing their bit, but Government authorities must wake up too
Aerosols are increasingly playing a significant role in changing the climate. These little floating particles are a natural part of the atmosphere coming from erupting volcanoes, sea salt, and wildfires. But of late, the burning of fossil fuels like coal, oil, and gas is generating even more more aerosols, leading to an increase in the severity of air pollution. This in turn is posing a serious threat for human health, as aerosols are one of the major components of fine particle pollution (PM2.5), which has been found to cause lung and heart problems and other adverse health effects.
The health impacts of aerosols consist of both short-term acute symptoms, like asthma and bronchitis, and long-term chronic irritation and inflammation of the respiratory track, which can potentially lead to cancer. According to the studies conducted by The Weizmann Institute in Israel and the National Aeronautics and Space Administration (Nasa) of the US, aerosols also impact the formation of cloud as well. Since clouds control the rainfall and regulate much of the earth’s warming, any change in the pattern of cloud formation affects the climate, which can have a cascading impact on the availability of fresh water and regional temperatures.
The New York Times recently reported a study conducted by the University of Maryland, which indicated that increases in aerosols due to air pollution from human activities could affect cloud formation in a way that causes drier regions to experience even less rain and wetter regions to experience more rainfall, snow and severe weather.
Given the adverse impact of aerosols, many countries are quickly putting in place action plans and strategies to clean up aerosols from the atmosphere. Aerosols are already increasing the acidification of the oceans, and this is putting marine life in danger, besides providing a platform for chemical reactions that are destroying the ozone layer. Additionally, the aerosol presence in the atmosphere is reducing the incoming solar radiation by reflecting it back into space. This is diminishing the efficiency of solar power systems to generate clean energy.Due to these ill effects, research and development on the impact of aerosols has been increased and the findings are being fed into national environmental policies.
India too has been suffering due to the impact of aerosols. Delhi is an apt example where urbanisation and industrialisation have grown rapidly, causing unprecedented levels of air pollution. As a consequence, carbonaceous aerosols emissions are increasing leading to poor ambient air quality for human health. Add to this, research studies have shown that higher levels of black carbon aerosol particle levels in the atmosphere are leading to a spike in average city temperatures. Much of the aerosol emissions are due to the vehicular traffic — and this is inspite of the majority of the city’s public transport running on CNG. Though the National Green Tribunal (NGT) has taken path-breaking steps to control vehicular emissions, there is still a lot to be done in order to rid the city of the aerosol pollution.
The magnitude of the problem posed by aerosol pollution is reflected in the recent study conducted by Jawaharlal Nehru University (JNU), which shows that the air in Delhi is full of carcinogenic particles. JNU’s Department of Environmental Sciences has come out with a toxicological risk assessment report that points to alarming levels of aerosol and heavy metals in the city’s air. The study was sponsored by the University Grants Commission and supported by the Ministry of Environment and Forests, and published by the National Academy of Sciences recently. The presence of particulate matter (PM), inhalable particles, in both diameter — PM2.5 and PM10 — and cancer-causing heavy metals such as nickel and cadmium in the capital’s air, has been found to be exceeding the permissible limits at peak traffic hours.
The concentration of PM2.5, in fact, has been found to be exceeding the limits (60ig/m3) prescribed by the Central Pollution Control Board in all areas. The effect of exposure to these pollutants on the health of population was studied in the age group of 18 to 45 years. The report showed that daily exposure to PM10 for eight hours for 10 years could cause 1,820 early deaths per one million population, due to acute diseases such as respiratory ailments. If people are exposed to PM2.5 for the same period, there is a possibility of an increase in the number of early deaths by 2,170 people per one million population.
Vehicular emission is the main cause of these deplorable conditions, as it contributes to about 63 per cent to the total pollution. This is followed by industries and thermal power plants — at 29 per cent — and domestic sector at eight per cent.
These alarming conditions in the country’s capital city-state need to serve as a wake-up call for the authorities to take note of the hazards that are posed by aerosol pollution. Urgent steps need to be taken to restore the purity of the air we breathe, in the best interests of our present and future generations.
(The writer is an environmental journalist)