Dr RG Wiseman Pinto
Pollution is no longer merely an environmental concern. It is a health emergency affecting almost every organ and system of the human body.
Pollution is a growing health concern affecting most of the world’s population. It is estimated to cause 7 million premature deaths globally. Some of the world’s most polluted cities are Delhi, Lahore, Cairo, Kolkata and Dhaka. In India, heavily polluted cities include Delhi, Noida, Gurgaon and Ghaziabad.
Goa is also getting increasingly polluted because of mining, industrial estates, waste disposal plants, coal handling, transportation and storage, construction of roads and buildings and hotel exhausts. In addition to air pollution, physical, chemical and biological agents are also involved.
The primary pollutants include carbon monoxide, nitrogen oxides, sulphur dioxide, particulate matter, lead and volatile organic compounds. Secondary pollutants are formed in the atmosphere, including ozone and smog. Biological agents include moulds, pollen and dust.
Major sources of pollution include vehicle emissions from cars, buses and trucks using petrol and diesel. Industries, power plants and cement factories contribute through the burning of fossil fuels such as coal, oil and gases. Pesticides, insecticides and fertilisers also contribute to pollution. Stubble burning, waste disposal, wildfires, fireworks, fog, dew and pigeons are additional sources.
Practically every organ and system of the human body can be affected by pollution. The respiratory system is particularly vulnerable. Airway irritation can lead to asthma, bronchitis, pneumonia, COPD, chronic pulmonary airway disease and lung cancer, as well as other cancers. Pollution is also associated with heart attacks, strokes and hypertension.
The brain and its cognitive functions are affected and this can lead to dementia. During pregnancy, pollution can contribute to preterm births and low birth weight, while neurological development in babies can be hindered. Infants, children, adults and the elderly are affected, as are pregnant women.
Pollution produces inflammation, irritation, oxidative stress and immunosuppression. It can also cause mutagenic damage to the DNA of cells. Irritation of the eyes, coughing, sneezing, sore throat, headache and fibrosis can occur. The brain, liver, kidneys, skin and immune system are affected. Pollution can also cause cataracts.
It can cause chromosomal breakage, shortening of telomeres and diabetes and can affect its control. Chronic inflammation is another consequence.
Pollution is not seasonal but occurs throughout the year. It is aggravated by smoking, allergies, asthma and pigeon droppings. Its effects extend beyond human health. Forests, fields, plants and animals are affected, while water, soil, plants and vegetation are also polluted.
Pollution damages crops and is a source of economic loss. It can also contribute to migration of people. There is loss of biodiversity. Global warming, acid rain and desert storms aggravate the problem.
The effects begin with irritation and inflammation and extend to oxidative stress, immunosuppression and damage to cellular DNA. These changes affect organs including the lungs, heart, brain, liver, kidneys. Pollution also affects the immune system and influence chronic inflammation, diabetes and its control. Damage is not confined to the respiratory tract. The presence of pollutants in air, water and soil means exposure can involve pathways and affect human health as well as wider ecosystem.
Pollution therefore represents a health crisis and a health emergency. It must be tackled at the earliest. The experience of Beijing and China shows that pollution can be addressed.
Reducing pollution requires attention to its many sources, from vehicles and industries to waste disposal, fossil fuels, agricultural practices and other environmental exposures. Since pollution affects people across all age groups and affects multiple organs and systems, its impact cannot be viewed as limited to one disease or one part of the body.
The continuing exposure of populations to polluted air and other environmental pollutants makes pollution an important health issue throughout the year. Its effects on humans, animals, plants, forests, fields, water and soil demonstrate the broad consequences of environmental pollution. Addressing this health emergency at the earliest is essential.
(The writer is a Professor of Pathology, former Head of Department at Goa Medical College, former Dean of Goa University, and the current President of the Asian Society of Cytopathology)
