Air pollution was the number five cause of death in 2015, claiming 4.2 million lives globally, according to new research out of Australia and New Zealand published in The Lancet.
The study found that deaths caused by particulate matter with an aerodynamic diameter less than 2.5µm (PM2.5) had increased from 3.5 million in 1990, and now represented 7.6 per cent of all deaths globally, with 59 per cent of deaths located in east and south Asia.
The research also found that air pollution led to 103.1 million lost years of healthy life in 2015.
The increase in death rates were related to population ageing, changes in non-communicable disease rates and increasing air pollution in low- and middle-income countries, the researchers found. Deaths were related to increases in ischaemic heart disease, cerebrovascular disease, chronic obstructive pulmonary disease, lung cancer and lower respiratory tract infection.
“Although global rates of mortality due to PM2.5 exposure decreased from 1990 to 2015 as a result of improved air quality in high-income countries and declining mortality rates for cardiovascular diseases, the absolute numbers of attributable deaths and [disability-adjusted life years] increased as a result of increases in pollution and the absolute numbers of deaths from non-communicable diseases, especially in China and India, where populations are both growing and ageing,” the study found.
“Household air pollution from the burning of solid fuels is also a major cause of mortality in low- income and middle-income countries, and together with ambient air pollution poses a substantial public health challenge.
While the figures are shocking, the authors said they had probably underestimated the complete burden of disease attributable to air pollution.
“Although the causes of mortality we included make up four of the five leading global causes of death in 2015, findings from systematic reviews in the past 10 years have shown that PM2.5 exposure is also associated with low birthweight and preterm birth, asthma and type 2 diabetes.”
The authors said “aggressive air quality management programs” could lead to “increased life expectancy over short timeframes”. This included targeting major sources of air pollution such as coal combustion, household burning of solid fuels and road transport.