Epidemiological Investigations into an Outbreak of Building-Associated Illness in Singapore

Abstract

In August 1991, the Ministry of the Environment was informed of the occurrence of illnesses suspected to be related to a modern, multi-story of fice building. Investigations revealed that 34 of the occupants on two floors of the building had non-specific ailments such as eye, throat or skin irritation which caused acute discomfort but resolved upon leaving the premises. Case-control study identified a number of factors significantly associated with the illness; viz. a personal history of allergy, asthma or sinusitis; a high level of work-related stress; and a lack of thermal comfort. One feature of the affected of fices was the numerous high partitions which tended to obstruct air movement. Adjustments of central temperature to compensate for complaints of “stuffiness” had resulted in wide fluctuations of temperature and relative humidity. Indoor air quality measurements also revealed high bacterial counts, a condition aggravated by the raised relative humidity and inadequate air movement. The problems gradually resolved following major modifications at the of fices and air-handling units. This episode confirmed the need for further studies of building-associated illness in the tropics. Asia Pac J Public Health1994;7(4):201-5.