New Delhi,  A team of Indian-origin researchers has found that the impact of breathing diesel exhaust fumes may be more severe for women than men.

Dr Hemshekhar Mahadevappa and Professor Neeloffer Mookherjee from the University of Manitoba in Winnipeg, Canada looked for changes in people's blood brought about by exposure to diesel exhaust.

In both females and males, they found changes in components of the blood related to inflammation, infection and cardiovascular disease, but they found more changes in females than males.

The research by Mahadevappa, Mookherjee and Chris Carlsten at the University of British Columbia, Vancouver, Canada will be presented at the European Respiratory Society International Congress in Barcelona, Spain, next week.

"We already know that there are sex differences in lung diseases such as asthma and respiratory infections. Our previous research showed that breathing diesel exhaust creates inflammation in the lungs and has an impact on how the body deals with respiratory infections," said Mahadevappa.

The new study involved 10 volunteers, five female and five male, who were all healthy non-smokers.

Each volunteer spent four hours breathing filtered air and four hours breathing air containing diesel exhaust fumes at three different concentrations, with a four-week break in between each exposure.

Volunteers donated blood samples 24 hours after each exposure and the researchers made detailed examinations of the volunteers' blood plasma.

Among the proteins that differed between females and males, were some that are known to play a role in inflammation, damage repair, blood clotting, cardiovascular disease and the immune system.

Some of these differences became clearer when volunteers were exposed to the higher levels of diesel exhaust.

"These are preliminary findings, however they show that exposure to diesel exhaust has different effects in female bodies compared to male and that could indicate that air pollution is more dangerous for females than males," said Mookherjee.

This is important as respiratory diseases such as asthma are known to affect females and males differently, with females more likely to suffer severe asthma that does not respond to treatments.

"Therefore, we need to know a lot more about how females and males respond to air pollution and what this means for preventing, diagnosing and treating their respiratory disease," said Mookherjee.

Professor Zorana Andersen from the University of Copenhagen, Denmark, said, "We also need to understand how and why air pollution contributes to poor health."

"This study offers some important insight into how the body reacts to diesel exhaust and how that may differ between females and males," said Andersen, Chair of the European Respiratory Society Environment and Health Committee, who was not involved in the research.