UK's most polluted towns and cities revealed

A polluted day in Ulaanbaatar Mongolia. Asia has some of the highest pollution levels worldwide

A polluted day in Ulaanbaatar Mongolia. Asia has some of the highest pollution levels worldwide. Credit BYAMBASUREN BYAMBA-OCHIR AFP

The Centre has made "serious" efforts to fight air pollution and the 2017 air quality data for fine particulate matter PM2.5 has shown improvement over the previous year, the environment ministry said on Wednesday, after a WHO report listed 14 Indian cities among the world's 20 most polluted.

More than 90% of air pollution-related deaths happen there, but cities in the Americas, Europe, and the Eastern Mediterranean also have air pollution levels that are beyond what the World Health Organization considers healthy.

If ambient air pollution (road, rail, river) alone is responsible for about 4.2 million deaths in 2016, indoor air pollution (fuels and polluting technologies) has caused about 3.8 million deaths that same year.

Risky for the lungs, heart, arteries or mucous membranes, overexposure to fine particles causes diseases such as strokes, heart disease, lung cancer, chronic obstructive pulmonary disease and respiratory infections.

Dr Gufran Beig, Project Director of the System of Air Quality Weather Forecasting and Research (SAFAR), which generates Air Quality Index (AQI) profile for Delhi, Mumbai, Pune and Ahmedabad expressed that he had his reservations in accepting the conclusions of the World Health Organization report, particularly about Indian cities and the authenticity of their data base.

A big issue in these regions is the lack of access to clean cooking fuels and technologies in their homes, which leads to air pollution inside of homes.

In a statement, the ministry said as most of the polluted cities lie around Delhi and along the Indo-Gangetic plain, it is critical that the governments of Uttar Pradesh, Bihar and West Bengal are sensitised to take up urgent action on cleaning air. About 3 billion people are breathing deadly fumes from domestic cooking stoves and fires, according to the Geneva-based agency. Besides the 14 Indian cities, the list has Kuwait's Ali Subah Al-Salem at the 15th spot with a PM 2.5 concentration of 94 micrograms per cubic meter.

The WHO report states that Kanpur is the most-polluted in the world with an annual PM2.5 average of 173 micrograms per cubic metre (µg/m3) and an annual PM10 (particulate matter of 10 micrometres or less in diametre) average of 319 (µg/m3).

Countries that are taking measures to reduce air pollution include India, WHO says, where one new scheme has provided free gas connections for more than 37 million women, to help them make the switch to clean energy use in the home.

Additional coverage of the WHO Global Urban Ambient Air Pollution Database is available from BBC News, CBS News, The Guardian, Healio, The Hill, and Xinhua News.

Latest figures in the report relating to the United Kingdom date from 2015 and are taken from readings from the Automatic Urban and Rural Network (AURN) of air pollution sensors.

To monitor the threat to public health posed by ambient air pollution, the WHO maintains a comprehensive, globally-focused database.

On some days, the air pollution in Srinagar is worse than that of Delhi and overall as bad as Kolkata.

In the fall, WHO will host the first Global Conference on Air Pollution and Health, aiming to bring governments and other entities together to improve air quality and address climate change.

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