A study carried out in 1996 by a team headed by Dr S K Chhabra of the Vallabhbhai Patel Chest Institute revealed that nine out of the 56 policemen observed (16 per cent) had chronic chest symptoms. Out of 32 subjects on whom bronchial provocation tests were carried out, 22 were found to be hyperactive. While 20 per cent of policemen after one year in service suffer from chronic bronchitis, irritation of eyes, nose and throat are the most common problems.