Paris - Churchgoing may be good for the soul but it could also be dangerous for the lungs, according to a study published on Friday in the specialist European Respiratory Journal.
University of Maastricht researcher Theo de Kok and colleagues measured levels of fine particulates in the air of a small chapel and a local basilica after experiments in which they burned candles for nine hours and simulated a service in which incense was burned.
Fine particulate matter - defined as solid particles with a diameter of 10 microns or less - is a devil among air pollutants.
These particles are so small that they can reach very deep into the lungs and, as they often comprise soot, metals or carcinogens, can cause a range of problems ranging from cancer to heart disease.
De Kok's team were astonished to find that, after the usual nine hours of candle-burning, church air had between 600 to 1 000 microgrammes of fine particulate matter per cubic metre.
This is 20 times the European Union (EU) limits for average concentrations of indoor air, as measured over 24 hours.
The news about incense was similarly grim.
"We also found very high concentrations of polycyclic aromatic hydrocarbons, well known to be carcinogenic, as well as various types of free radicals, including some previously undocumented ones," said De Kok.
Free radicals are rogue molecules blamed for damaging lung tissue and triggering a range of inflammatory reactions, such as asthma and chronic bronchitis.
De Kok says further work is needed to verify these findings.
He believes the discovery is "very worrying," for it implies that priests and churchworkers - and even devout worshippers who spend several hours each day in church - face the risk of respiratory damage. - Sapa-AFP