Sick Building Syndrome Associated With Fungi

December 7, 2011 (Cancun, Mexico) — In nonsealed buildings in a tropical environment, sick building syndrome (SBS) is associated with the presence of fungi, but not chemical products, mites, or endotoxin, according to research presented here at the World Allergy Organization XXII World Allergy Congress.

SBS is a constellation of symptoms, including cough, irritation of the nose or throat, headache, fatigue, and trouble concentrating. The researchers suspected that the variation in indoor air quality between sealed (climate-controlled) and nonsealed buildings might contribute to SBS.

They compared the incidence of SBS among the occupants of 2 buildings in downtown Rio de Janeiro, Brazil — 1 sealed (160 of 210 full-time employees working in the building for more than 1 year were evaluated) and 1 nonsealed (164 of 186 full-time workers evaluated). SBS was diagnosed with a medical examination and a questionnaire. Participants who indicated on the questionnaire that they had 3 or more symptoms were considered to have SBS. The team used standardized international methodologies to assess the indoor concentration of fungi, mites, and endotoxin.

In the sealed building, 44.8% of occupants had SBS, compared with 48.6% of those in the nonsealed building (P = .48). In the sealed building, the researchers found that none of the occupants had significant exposure to fungi, whereas 35.4% of the occupants in the nonsealed building were exposed.

A multivariate regression analysis of endotoxin, mite, and fungi exposure showed no association with SBS in the sealed building. In the nonsealed building, the analysis revealed that fungi exposure was the unique significant risk factor (odds ratio, 3.11; 95% confidence interval, 1.29 to 7.48; P = .01).

The researchers believe that the association between SBS and fungi growth in the nonsealed building was likely due to a higher relative humidity.

The results are likely applicable to other tropical and subtropical climates, according to José Laerte Boechat, PhD, professor of allergy and immunology at Federal Universidad de Rio de Janeiro, who presented the research. “I think they have similar problems in places like Indonesia, China, and India,” Dr. Boechat told Medscape Medical News.

The results of the study are surprising, said Myron Zitt, MD, clinical associate professor at the State University of New York at Stonybrook, who comoderated the session. “One would anticipate that the group in the sealed building would have more SBS symptoms because they’re sealed in and exposed to higher levels [of environmental contaminants], but that wasn’t the case,” Dr. Zitt told Medscape Medical News.

Dr. Boechat and Dr. Zitt have disclosed no relevant financial relationships.
World Allergy Organization XXII World Allergy Congress (WAC): Abstract 2199. Presented December 6, 2011.

Medscape Medical News from the:
World Allergy Organization XXII World Allergy Congress (WAC)
This coverage is not sanctioned by, nor a part of, the World Allergy Organization.
Jim Kling