After taking into account patient risk factors including age, diabetes and hypertension, the investigators found a link between the prevalence of chronic kidney disease (CKD) and the increasing level of particulate matter (PM) in some areas in the United States.

An elevated prevalence of CKD was observed when particulate matter levels were as low as 8.4 microgram per cubic metre - which is much lower than levels typically considered to be unhealthy for sensitive groups such as the elderly (40 microgram per cubic metre).

"If air pollution is a risk factor for CKD, the impact is likely to be even greater in countries where pollution levels are much higher than in the US," said lead study author Jennifer L. Bragg-Gresham from the University of Michigan in the US.

In October, the US embassy's pollution monitor in New Delhi labelled its air quality as "very unhealthy" - at 248 microgram per cubic metre.

"Future investigations should include lab-based diagnosis of CKD, longitudinal data, measures of multiple air pollutants and individual exposure," Bragg-Gresham added.

The findings was presented at the "ASN Kidney Week 2014" at the Pennsylvania Convention Center in Philadelphia.