Long-term exposure to air pollution increases the risk of diabetes, according to a recent Chinese study.

Diabetes causes substantial economic and health burdens worldwide. China has the highest number of diabetic cases in the world.

However, the association between air pollution and diabetes incidence is rarely reported in developing countries, especially in China which has a relatively high PM 2.5 concentrations, state-run Xinhua news agency reported quoting the study.

PM 2.5 or fine particulate matter is an air pollutant that is a concern for people's health when levels in air are high. PM 2.5 are tiny particles in the air that reduce visibility and cause the air to appear hazy when levels are elevated.

Researchers from Chinese Academy of Medical Sciences' Fuwai Hospital  in collaboration with US-based Emory University evaluated the association between long-term exposure to PM 2.5 and diabetes cases based on data collected from over 88,000 Chinese adults.

The research team used satellite-based PM 2.5 concentrations to assess its exposure for each subject during the period 2004-2015.

Results showed that the risk of diabetes increased by 15.7 per cent for an increase of 10 micrograms per cubic meter of long-term PM 2.5 concentration.

The adverse effects of PM 2.5 were higher among young to middle-aged subjects, females, non-smokers and subjects with lower body mass index, the Xinhua report said.

The study, which was published in the Environment International journal, revealed that PM 2.5 was an important risk factor for diabetes in China and sustained improvement of air quality will help decrease the diabetes epidemic in the country.

Lu Xiangfeng, one of the researchers, said the study would benefit policy making and intervention design in diabetes prevention.

"Our future work will focus on introducing spatiotemporal data of PM 2.5 at higher resolution and indoor source of exposures to further detect the health effects of long-term exposure to PM 2.5," Lu said.