High levels of pollution mainly caused by India are severely affecting parts of Pakistan as the life expectancy of Pakistanis reduce by around four years.

India is responsible for about 59% of the world’s increase in pollution since 2013, as hazardous air threatens to shorten lives further in some of the country’s more polluted regions, the University of Chicago’s Energy Policy Institute said in its latest Air Quality Life Index.

An average Pakistani resident would gain three years and nine months after meeting the World Health Organization (WHO) guidelines of limiting average annual particulate matter 2.5 concentration to 5 microgrammes per cubic metre, while someone in Nepal would live 4.6 years longer if the guideline was met, according to the report.

Amid increasing population, the average life span is down by more than 10 years in the densely populated New Delhi, the world’s most polluted mega-city.

South Asia region is one of the world’s most polluted regions where rising air pollution can cut life expectancy by more than five years per person , according to the report, which flagged the growing burden of hazardous air on health.

The region, home to the world’s most polluted countries of Bangladesh, India, Nepal and Pakistan, accounts for more than half of the total life years lost globally to pollution.

Rapid industrialisation and population growth have contributed to declining air quality in South Asia, where particulate pollution levels are currently more than 50% higher than at the start of the century and now overshadow dangers posed by larger health threats.

People in Bangladesh, the world’s most polluted country, stands to lose 6.8 years of life on average per person, compared to 3.6 months in the United States, according to the study, which uses satellite data to calculate the impact of an increase in airborne fine particles on life expectancy.

Reducing global levels of lung-damaging airborne particles, known as PM 2.5, to levels recommended by the WHO could raise average life expectancy by 2.3 years, or a combined 17.8 billion life years, the report said.

China, meanwhile, has worked to reduce pollution by 42.3% between 2013 and 2021, the report said, highlighting the need for governments to generate accessible air quality data to help bridge global inequalities in accessing tools to combat pollution.