Is your car’s air con home to a potential health hazard?

MOTORISTS are being urged to clean the air conditioning units in their cars after researchers found potentially dangerous bacteria living and breeding in systems.

With the weather warming up, the study shows drivers may be putting their health at risk when they reach for the cool switch.

Bacteria associated with meningitis, urinary tract infections and septic arthritis were among the varieties discovered in air conditioning filters.

Swabs of 15 air conditioning filters were taken from cars across the UK and sent for laboratory analysis. Micro-organisms were detected in all of the filters tested at London Metropolitan University.

The most common was Bacillus licheniformis, a bacteria most commonly associated with birds and soil. Eight out of 15 of the filters tested positive for this micro-organism, which is among a type of bacteria known to cause food poisoning.

Bacillus subtilis and Bacillus were the second most common microorganisms found. Bacillus subtilis are normally found in the gastrointestinal tract of humans and some mammals. They generally do not cause disease but have been known to cause septicaemia in a patient with leukaemia. Bacillus has links with a wide range of infections including meningitis and septicaemia.

A car’s air con works by mixing fresh air from outside with a refrigerant and the mixture turns into liquid as it is cooled. It is then turned into vapour that’s blown into the cabin as cool air. The evaporator provides perfect conditions for bacteri to build up and thrive. A filter will prevent many pollutants entering the passenger compartment – but not all micro-organisms.

Dr Paul Matewele, a senior lecturer in microbiology at London Metropolitan, said: ‘The study underlines the importance of cleaning and replacing filters.’