Cinema seats could trigger wheezing in asthma sufferers because they are packed with allergens spread from cat fur, a study suggests.
The problem may be linked to the way cats lick themselves
Tests revealed they contain high levels of allergens thought to have come off the clothes of cinema-going cat lovers.
The findings, presented at the European Academy of Allergology and Clinical Immunology annual meeting in Paris, suggest a trip to the movies could be potentially hazardous for asthma sufferers who are allergic to cat fur.
They also back earlier studies from New Zealand, which showed both cinema seats, and aircraft seats, were contaminated with dangerously high levels of cat allergens.
However, the latest research, carried out by experts at the Scientific Institute of Public Health in Brussels, shows there is little or no health risk from carpets in cinemas as they contain relatively low levels of bacteria, moulds, toxins and allergens.
'Spread by clothes'
"The contamination of carpets by micro-organisms and endotoxins was inferior to the mean rates detected in domestic dusts," said Dr Nicole Nolard, who led the research.
"But the concentrations of cat allergens were moderate in carpets and high in seats. These allergens were mainly carried and spread with clothes. Spectators are contaminating cinema seats."
It is easy to see how cat owners drag it into cinemas on their clothes.
Dr Chris Corrigan, Guy's and St Thomas's Hospital
For years, allergy experts have been studying the levels of domestic allergens in public buildings and transport systems, in a bid to assess the risk to sufferers outside of the home.
The latest study looked at six giant entertainment theatres in Belgium. Over a two-year period, scientists investigated 35 cinemas, taking dust samples from carpets and seats. Air samples were also taken.
The results showed very low levels of mould - less than would be found in most home carpets - and 'rather low' levels of bacteria.
Contamination by house dust mite and potentially harmful toxins was also within safe levels.
But the quantities of a common cat allergen known as Fel d1 were 'moderately' high in carpets and 'very high' in seats.
Dr Chris Corrigan, a specialist in allergies at Guy's and St Thomas' Hospital in London, said cat allergen may be a particular problem because of the way cats clean themselves.
"Fel d1 is a gut enzyme, present on fur only because cats lick themselves clean so frequently. I suppose the combined stickiness of saliva and the frequency with which cats lick themselves explains a lot of it. It is easy to see how cat owners drag it into cinemas on their clothes.
"I have certainly treated patients who experience significant, acute symptoms even when entering a room where a cat had been prowling around, sometimes days or weeks previously. In that sense, cat allergen in cinemas could pose a health risk to some patients."
Dr Corrigan said other studies due to be published shortly show cat allergens are even present in homes where cats have never been kept.
"This suggests it may soon become an ubiquitous allergen like pollen, fungal spores and dust mite."