In 2010, air pollution killed nearly 600,000 people in India, according to the World Health Organisation (WHO). The situation has not changed in the last five years. A recent study shows that a significant population of Indian subcontinent breathes air with much higher particulate matter that is lesser than 2.5 micrometre (PM2.5) in size than the limit set by the WHO. Outdoor air pollution as a whole, especially the particulate matter, has been declared as class-1 cancer-causing agent (carcinogen) in 2013 by the International Agency for Research on Cancer (IARC), which is part of the WHO. Besides, it causes other respiratory and heart diseases.
The PM2.5 is particularly dangerous and can cause adverse health effects owing to its greater penetrability into the human respiratory system and eventual accumulation in human organs and blood. Rural women, children and elderly population are more prone to diseases caused by air pollution. Rural women, in particular, face a greater risk from indoor pollution — locally made mud stoves fuelled by solid biofuel emit a far greater amount of finer particulate matter.
Air quality of any area depends on local emissions, long-range transport, local and regional weather patterns, and to some extent the topography of the region. Due to increased buoyancy and efficient ventilation in summer, pollution plumes rise effortlessly to the free atmosphere. This leads to a reduced level of surface level PM2.5 concentration in our breathing zone. The problem gets aggravated during winter. Adverse conditions during winter help trapping of pollution leading to elevated level of surface PM concentration.
Source : The Hindu ,7 May 2015