Symptoms prevalence among office workers of a sealed versus a non-sealed building: associations to indoor air quality.
OBJECTIVE
An increasing number of complaints related to time spent in artificially ventilated buildings have been progressively reported and attributed, at least in part, to physical and chemical exposures in the office environment. The objective of this research was to investigate the association between the prevalence of work-related symptoms and the indoor air quality, comparing a sealed office building with a naturally ventilated one, considering, specially, the indoor concentration of TPM, TVOCs and the main individual VOCs.


METHODS
A cross-sectional study was performed to compare the prevalence of sick building syndrome (SBS) symptoms among 1736 office workers of a sealed office building and 950 of a non-sealed one, both in Rio de Janeiro's downtown. The prevalence of symptoms was obtained by a SBS standardized questionnaire. The IAQ of the buildings was evaluated through specific methods, to determine the temperature, humidity, particulate matter and volatile organic compound (VOC) concentrations.


RESULTS
Upper airways and ophthalmic symptoms, tiredness and headache were highly prevalent in both buildings. Some symptoms were more prevalent in the sealed building: "eye dryness" 33.3% and 27.1% (p: 0.01); "runny nose" 37.3% and 31.3% (p: 0.03); "dry throat" 42% and 36% (p: 0.02); and "lethargy" 58.5% and 50.5% (p: 0.03) respectively. However, relative humidity and indoor total particulate matter (TPM) concentration as well as total volatile organic compounds (TVOCs) were paradoxically greater in the non-sealed building, in which aromatic compounds had higher concentration, especially benzene. The analysis between measured exposure levels and resulting symptoms showed no association among its prevalence and TPM, TVOCs, benzene or toluene concentration in none of the buildings.


CONCLUSIONS
Other disregarded factors, like undetected VOCs, mites, molds and endotoxin concentrations, may be associated to the greater prevalence of symptoms in the sealed building.
Rios
José Luiz de Magalhães
JL
Federal University of Rio de Janeiro, Brazil. Clementino Fraga Filho University Hospital, Institute of Thoracic Diseases. jlrios@globo.com
Boechat
José Laerte
JL
Gioda
Adriana
A
dos Santos
Celeste Yara
CY
de Aquino Neto
Francisco Radler
FR
Lapa e Silva
José Roberto
JR
D000395:Air Pollutants, Occupational / Q000032:analysis*; D016902:Air Pollution, Indoor / Q000032:analysis*; D004784:Environmental Monitoring; D062665:Epidemiological Monitoring; D006306:Health Surveys; D006813:Humidity; D019570:Inhalation Exposure / Q000032:analysis*; D009784:Occupational Diseases / Q000453:epidemiology*; D052638:Particulate Matter / Q000032:analysis; D015995:Prevalence; D018877:Sick Building Syndrome; D013696:Temperature; D014691:Ventilation; D055549:Volatile Organic Compounds / Q000032:analysis
D000395:Air Pollutants, Occupational; D052638:Particulate Matter; D055549:Volatile Organic Compounds