A recent study led by Chinese scientists shows a strong link between smaller air pollution particles and a range of serious health conditions.

Scientists said the smaller the airborne particles, the more likely they are to cause illness, suggesting the need for monitoring of particulate matter of 1 micron or less in diameter — a category of pollution rarely monitored.

In recent years, many locations across the country have been blanketed with heavy air pollution, raising concerns for public health. Among the main categories of pollutant measured is PM2.5, which can enter the respiratory system and contribute to a range of illnesses, including cardiovascular disease.

Now, in a new study published in the public health journal Environmental Health Perspectives, researchers from the School of Public Health at Fudan University in Shanghai have demonstrated correlations between PM2.5 pollution and the incidence of particular illnesses.

Researchers spent about two years collecting data in a medium-sized city in northern China, measuring the levels of particulate matter in 23 size categories ranging from 0.25 microns to 10 microns. They then plotted the health conditions of residents in the city against the concentrations of particles of different sizes found in their locations.

Among the key findings was that those areas with larger concentrations of smaller particles showed higher incidences of particular illnesses.

"Our study, based on epidemiological investigation, showed that fine particles in the air measuring between 0.25 to 0.5 microns in diameter have a closer relationship to human health, especially an increased risk of cardiovascular diseases," said Kan Haidong, a professor at the School of Public Health at Fudan University.