Sick building syndrome: psychological, somatic, and environmental determinants

Patient barriers and facilitators for making environmental and behavioral modifications for dry eye in the United States

BACKGROUND

Managing dry eye disease (DED) is expensive. Often, prescribed treatments improve clinical signs but not patient-reported symptoms. In large surveys, clinicians and patients ranked environmental and behavioral modifications among the most important DED-related research priorities. Our purpose was to investigate the barriers to and facilitators of use of these modifications by patients with DED in the United States and how their use may be impacted by socioeconomic status (SES).

METHODS

Using Qualtrics, we conducted an anonymous online survey of adults with DED living in the United States in August to September 2022. Patients were identified through the Dry Eye Foundation, Sjögren's Foundation, and a DED clinic in Colorado. We used an established index for classifying respondent SES based on education, household income, and employment. Outcomes included use of environmental and behavioral modifications and barriers to and facilitators of their use.

RESULTS

We included 754 respondents (SES: 382 low, 275 high, and 97 unclear). Most were aged 18 to 49 years (67%), female (68%), and White (76%) and reported dealing with DED for ≤5 years (67%). The most frequent modifications were taking breaks to rest eyes (68%), increasing water intake (68%), and using hot/cold compresses (52%). For these three, the biggest facilitators were as follows: belief that the modification works (27 to 37%), being recommended it (24 to 26%), and ease of use/performance (21 to 32%). Across modifications, the biggest barriers were difficulty of use (55%), lack of family/employer/social/community support (33%), and lack of awareness (32%). The data do not suggest discernible patterns of differences in barriers or facilitators by SES.

CONCLUSIONS

Greater emphasis should be placed on explaining to patients how environmental and behavioral modifications might mitigate DED. Employers and members of patients' support systems should be guided regarding how best to support patients in managing DED symptoms.

Prevalence of sick building syndrome in hospital staff and its relationship with indoor environmental quality

The aim of this study was to determine the prevalence of sick building syndrome (SBS), and its relationship with indoor environmental quality in hospital settings. This cross-sectional study was carried out on 300 hospital staff in Sivas. MM 040 NA Hospital questionnaire was applied. In the hospital indoor environments, air quality (carbon monoxide (CO), carbon dioxide (CO₂), oxygen (O₂), methane (CH₄), hydrogen sulfide (H₂S), nitrogen oxides (NO_x)), lighting, noise, respirable dust and thermal comfort measurements were made. The prevalence of SBS was determined as 64.7-74.1% in the hospitals. It was found that the risk of SBS was 4.31 times higher for those who complained about variable room temperature and 3.11 times higher for those who complained about noise, and decreased 1.01 times with the increase in lighting level. In order to minimize the risk of SBS, it is thought that all healthcare administrators should be informed about SBS.

Exposures, Symptoms and Risk Perception among Office Workers in Relation to Nanoparticles in the Work Environment

Submicroscopic nanoparticles (NPs) in air have received much attention due to their possible effects on health and wellbeing. Adverse health impacts of air pollution may not only be associated with level of exposure, but also mediated by the perception of the pollution and by beliefs of the exposure being hazardous. The aim of this study was to test a model that describes interrelations between NP pollution, perceived air quality, health risk perception, stress, and sick building syndrome. In the NanoOffice study, the level of NPs was measured and a survey on health risk perception was conducted among 260 employees in twelve office buildings in northern Sweden. Path analyses were performed to test the validity of the model. The data refute the model proposing that the NP exposure level significantly influences stress, chronic diseases, or SBS symptoms. Instead, the perceived exposure influences the perceived risk of NP, and the effect of perceived exposure on SBS and chronic disease is mediated by stress. There was little concern about nanoparticles, despite relatively high levels in some facilities. Perceived pollution and health risk perception may explain a large part of the environmentally induced symptoms and diseases, particularly in relatively low levels of pollution. The research results raise important questions on the physiologically or psychologically mediated health effects of air pollution.

Psychosocial factors and indoor environmental quality in respiratory symptom reports of pupils: a cross-sectional study in Finnish schools

OBJECTIVES

Poor indoor environmental quality (IEQ) in schools is related to higher respiratory symptoms of pupils, but little is known about the importance of other factors. This study examined the associations between different psychosocial factors and other pupils' individual and allergic characteristics, beyond school IEQ, and reporting of respiratory symptoms in pupil-administered and parent-administered questionnaires.

SETTING

All primary and secondary schools in two areas of Helsinki, Finland.

PARTICIPANTS

Primary school pupils (grade 3-6, n=8775, 99 school buildings) and secondary school pupils (grade 7-9, n=3410, 30 school buildings) reported their respiratory symptoms, as well as psychosocial factors and individual characteristics. Parents of primary school pupils (grade 1-6, n=3540, 88 school buildings) also filled in questionnaires, but the response rate was low (20% in 2017 and 13% in 2018).

MAIN OUTCOME MEASURE

Respiratory symptoms were reported in relation to the school environment and in general (without such relation) by pupils or parents.

RESULTS

Worry about IEQ and low school satisfaction, and asthma and hay fever were related to higher reporting of respiratory symptoms in three samples. The variance between schools in respiratory symptoms was low (intraclass correlation=0.6%-2.4%). Psychosocial factors, especially worry about school's IEQ, explained more of the variance between schools in symptoms than IEQ among secondary school pupils and parents, but not among primary school pupils for symptoms in general. Worry about IEQ also modified the associations between IEQ and respiratory symptoms, but only in parental reports.

CONCLUSION

In addition to IEQ, psychosocial factors and pupils' individual and allergic characteristics were related to higher reporting of respiratory symptoms in all three samples. Psychosocial factors explained more variance between schools than IEQ, although it was 2.4% at most. Other factors beyond IEQ should be considered when interpreting symptom reporting in indoor air questionnaires.

Prevalence of sick building syndrome symptoms and its associated factors among bank employees in Pokhara Metropolitan, Nepal

A cross-sectional study was conducted to assess the prevalence of sick building syndrome symptoms and its associated factors among bank employees. Data were collected through a self-administered MM040NA questionnaire among 234 employees of commercial banks in Pokhara Metropolitan, Nepal. The prevalence of general, ocular, respiratory, and dermal sick building syndrome symptoms was 47.6%, 11.9%, 11.9%, and 8.1%, respectively. The perceived indoor physical environment was a significant predictor of sick building syndrome symptoms. Besides this, age, disturbance from temperature and work pressure were significantly associated with general symptoms. Ocular symptoms were significantly associated with disturbance from noise at their workplaces and support from fellow workers. Respiratory symptoms were significantly associated with the time spent working with a photocopy machine. Proper maintenance of room temperature, noise control, good ventilation system, and promotion of supportive psychosocial working environment at banks is important to prevent and control the suffering of employees from SBS symptoms.

Psychosocial treatments for employees with non-specific and persistent physical symptoms associated with indoor air: A randomised controlled trial with a one-year follow-up

OBJECTIVE

Persistent physical symptoms (PPS) associated with indoor air without an adequate pathophysiological- or environmental-related explanation may lead to work disability and decreased health-related quality of life (HRQoL). We attempted to assess the effect of cognitive behavioural therapy (CBT) for PPS and also psychoeducation (PE) on these symptoms involving disability.

METHOD

The intention-to-treat (ITT) sample included 52 employees recruited from an occupational healthcare service randomised as either controls undergoing treatment as usual (TAU) or TAU enhanced with CBT or PE. The primary outcome was HRQoL measuring the severity of symptoms and restrictions in everyday life caused by them. Secondary outcomes included depressive, anxiety and insomnia symptoms, and intolerance to environmental factors, assessed at baseline and at 3-, 6- and 12-month follow-ups.

RESULTS

At the 12-month follow-up assessment point, no statistically significant differences between treatments emerged following adjustment for gender, age, and HRQoL before the waiting period in the ITT analysis [F(2,46)=2.89, p=.07]. The secondary analysis revealed a significant improvement in HRQoL in the combined intervention group as compared with controls [F(1,47)=5.06, p=.03, g=0.41]. In total, 15% of participants dropped out during follow-up.

CONCLUSIONS

The results suggest that CBT for PPS or PE might not have a robust effect on HRQoL in PPS associated with indoor air, but the study did not achieve the planned power. Despite difficulties during the recruitment process, the final dropout rates remained low, and participants positively evaluated CBT, suggesting that it represents an acceptable treatment to them. Trial status This study was registered at the ClinicalTrials.gov registry (NCT02069002).

Prevalence and risk factors of pre-sick building syndrome: characteristics of indoor environmental and individual factors

BACKGROUND

With the aim to prevent sick building syndrome and worsening of allergic symptoms, primarily resulting from the indoor environment, the relationships among people's residential environment in recent years, their lifestyle habits, their awareness, and their symptoms were investigated using an online survey.

METHODS

In the survey, respondents experiencing symptoms specific to sick building syndrome, although they were not diagnosed with sick building syndrome, were categorized in the pre-sick building syndrome group. The relationships among individual characteristics, residential environment, and individual awareness were analyzed.

RESULTS

Results showed that the prevalence of pre-sick building syndrome was high among young (aged 20-29 years) population of both sexes. In addition, "condensation," "moisture," "musty odors" in the house, and the "use of deodorant and fragrance" were all significantly associated with pre-sick building syndrome. Conversely, there was no significant association with recently built "wooden" houses that are highly airtight and have thermal insulation.

CONCLUSIONS

Efficient "ventilation" plans and "ventilation" improvement and air conditioning systems to prevent mold and condensation in rooms are necessary to maintain a good, indoor environment that is beneficial for health. Efforts should also be made to encourage individuals to regularly clean and effectively ventilate their homes.

Health-related quality among life of employees with persistent nonspecific indoor-air-associated health complaints

OBJECTIVE

Nonspecific health complaints associated with indoor air are common in work environments. In some individuals, symptoms become persistent without an adequate explanation. The aim was to study factors that associate with the health-related quality of life (HRQoL) of employees with persistent, nonspecific indoor-air-related symptomatology.

METHODS

We present baseline results of a randomized controlled trial of interventions targeted on the HRQoL of the employees with indoor-air-associated nonspecific symptoms. The main participant-inclusion criterion was the presence of persistent indoor-air-related multiorgan symptoms with no known pathophysiological or environment-related explanation. As a comparison for participants´ HRQoL (n = 52) we used data from the general-population Health 2011 study (BRIF8901) including information on subjects matched to the participants´ working status and age and subjects with asthma, anxiety or depressive disorder, or other chronic conditions with work disability.

RESULTS

The participants showed greater and a clinically significant impairment of HRQoL [M = 0.83, SE = 0.013] than individuals from the general population [M = 0.95, SE = 0.001, p < .001, Hedges´ g = 2.33] and those with asthma [M = 0.93, SE = 0.005, p < .001, Hedges´ g = 1.46], anxiety and depressive disorder [M = 0.89, SE = 0.006, p < .001, Hedges´ g = 0.73], or a chronic condition with work disability [M = 0.91, SE = 0.003, p < .001, Hedges´ g = 1.11]. Prevalent symptoms of depression, anxiety, and insomnia and poor recovery from work were associated with a poor HRQoL.

CONCLUSIONS

Individuals with nonspecific indoor-air-associated symptoms have a poorer HRQoL than individuals in the general population with a globally burdensome disease. Psychological distress associated with a poor HRQoL should be considered in the making of decisions about the treatment of these patients.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02069002.

Building-Related Environmental Intolerance and Associated Health in the General Population

People frequently attribute adverse symptoms to particular buildings when exposure to pollutants is low, within nonhazardous levels. Our aim was to characterize building-related intolerance (BRI) in the general population. Data were derived from two population-based questionnaire surveys, the Västerbotten and Österbotten Environmental Health Study. We identified cases of BRI if respondents reported symptoms emerging from residing in certain buildings, when most other people had none. The questionnaires covered lifestyle factors, perceived general health, BRI duration and symptom frequency, the emotional and behavioral impact of BRI, coping strategies, and physician-diagnosed diseases. From the total of 4941 participants, we formed two case groups, 275 (5.6%) fulfilled criteria for self-reported BRI, and 123 (2.5%) for BRI with wide-ranging symptoms. Individuals in both case groups were significantly more often female, single, and perceived their general health as poorer than the referents, i.e., those reporting no BRI symptoms. The mean duration of BRI was 12 years. In both case groups, avoidance behavior was found in over 60%, and nearly half of the sample had sought medical care. BRI with wide-ranging symptoms was associated with elevated odds for all studied comorbidities (somatic and psychiatric diseases and functional somatic syndromes). The perceived health of individuals with BRI is poorer and comorbidities are more frequent than among referents. BRI seems to be similar to other environmental intolerances and shares features with functional somatic syndromes.

Outdoor air pollution, meteorological conditions and indoor factors in dwellings in relation to sick building syndrome (SBS) among adults in China

Indoor environment is associated with the sick building syndrome (SBS), but little is known about the contribution of outdoor air pollution and meteorological conditions to SBS. We studied associations between outdoor air pollution, meteorological parameters and selected indoor exposure and building characteristics at home and weekly SBS symptoms in a standardized questionnaire study among 3485 randomly selected adults in China. Outdoor factors included particulate matters with diameter <10μm (PM10), sulfur dioxide (SO2), nitrogen dioxide (NO2), outdoor temperature (T), relative air humidity (RH), and wind speed (WS) during last three months. Multiple logistic regression was applied calculating odds ratios (OR) with 95% confidence interval (95% CI). Asthma or allergic rhinitis (atopy) was associated with all types of SBS symptoms except fatigue. Indoor factors played a major role in SBS symptoms. Mold/dampness on the floor/ceiling was associated with fatigue OR=1.60 (1.11-2.30) and headache OR=1.80 (1.07-3.04). Moldy odor was associated with fatigue OR=1.59 (1.07-2.37) and dermal symptoms OR=1.91 (1.21-3.02). Window pane condensation in winter was associated with fatigue OR=1.73 (1.30-2.31) and throat symptoms OR=1.53 (1.01-2.31). Damp bed clothing was related with throat symptom OR=1.62 (1.09-2.40). Home redecoration was associated with fatigue OR=1.49 (1.07-2.06). Frequent window opening was associated with less nose symptoms OR=0.54 (0.36-0.82) and mechanical ventilation in the bathroom reduced dermal symptoms OR=0.66 (0.44-0.99). Females were more susceptible to redecoration and window pane condensation than men. No associations with SBS were observed for outdoor air pollutants or meteorological parameters in the final models combining indoor and outdoor factors, although SO2, T, and RH were associated with some SBS symptoms (fatigue, eyes and nose symptoms) in the separate outdoor models. In conclusion, indoor mold/dampness, air pollution from redecoration and poorer ventilation conditions in dwellings can be risk factors for SBS symptoms in an adult Chinese population, especially among females.

Prevalence and risk factors of sick building syndrome among office workers

BACKGROUND

Sick building syndrome (SBS) is a group of symptoms relatively common among office workers; such symptoms could have an impact on the workers' productivity. The aim of this study is to measure the prevalence of SBS symptoms among office workers in the Faculty of Medicine, Ain Shams University, Cairo, Egypt, and to determine the possible risk factors.

PARTICIPANTS AND METHODS

A cross-sectional study was carried out at the Ain Shams Faculty of Medicine including 826 workers. Data were collected through a self-administered questionnaire that included sociodemographic and occupational histories, work environment, and symptoms related to SBS.

RESULTS

Fatigue and headache were the most prevalent symptoms (76.9 and 74.7%, respectively). Using univariate analysis, poor lighting, poor ventilation, lack of sunlight, absence of air currents, high noise, temperature, humidity, environmental tobacco smoke, use of photocopiers, and inadequate office cleaning were associated statistically with SBS symptoms (P<0.05). High work load and poor job satisfaction were also associated significantly with SBS symptoms (P<0.05). Logistic regression analysis showed that poor ventilation, poor lighting, environmental tobacco smoke, high temperature, poor job satisfaction, and inadequate office cleaning were the risk factors of SBS.

CONCLUSION AND RECOMMENDATIONS

SBS was highly prevalent among office workers and was influenced by physical and psychosocial working conditions. Good ventilation, reducing room temperature, effective cleaning routines, providing proper lighting, restricting smoking in the workplace, and improving psychosocial working conditions are important ways to reduce SBS symptoms.

Gaseous chemical compounds in indoor and outdoor air of 602 houses throughout Japan in winter and summer

A nationwide survey of indoor air quality in Japan was conducted using four types of diffusive samplers. Gaseous chemical compounds such as carbonyls, volatile organic compounds (VOC), acid gases, basic gases, and ozone were measured in indoor and outdoor air of 602 houses throughout Japan in winter and summer. Four kinds of diffusive samplers were used in this study: DSD-BPE/DNPH packed with 2,4-dinitrophenyl hydrazine and trans-1,2-bis(2-pyridyl)ethylene coated silica for ozone and carbonyls; VOC-SD packed with Carboxen 564 particles for volatile organic compounds; DSD-TEA packed with triethanolamine impregnated silica for acid gases; and DSD-NH3 packed with phosphoric acid impregnated silica for basic gases. These samplers are small and lightweight and do not require a power source, hence, it was possible to obtain a large number of air samples via mail from throughout Japan. Almost all compounds in indoor air were present at higher levels in summer than in winter. In particular, formaldehyde, toluene, and ammonia were strongly dependent on temperature, and their levels increased with temperature. The nitrogen dioxide concentration in indoor air particularly increased only during winter and was well correlated with the formic acid concentration (correlation coefficient=0.959). Ozone concentrations in indoor air were extremely low compared with the outdoor concentrations. Ozone flowing from outdoor air may be decomposed quickly by chemical compounds in indoor air; therefore, it is suggested that the indoor/outdoor ratio of ozone represents the ventilation of the indoor environment.

Social determinants of the sick building syndrome: exploring the interrelated effects of social position and psychosocial situation

This paper examines the importance of various social factors for the prevalence of "sick building syndrome" (SBS) in residential buildings. A survey has been conducted in Malmö, Sweden, resulting in 1131 randomly selected residents participating in the study (response rate 57 %). Two clusters of social factors were examined: the socio-structural position of the individual and psychosocial aspects of the housing situation. The results show that country of birth, in particular, and also education and employment status are important predictors of "domestic SBS". "Housing satisfaction" turns out to be an important psychosocial predictor of SBS, explaining, for example, why immigrants report more symptoms than natives.

Allostatic load model associated with indoor environmental quality and sick building syndrome among office workers

This study investigates whether indoor environmental quality (IEQ) influences allostatic load (AL) and whether AL can be a predictor for sick building syndrome (SBS). We also assessed and compared the associations between AL and SBS versus 8-hydroxydeoxyguanosine (8-OHdG) and SBS. A total of 115 office workers from 21 offices completed self-reported SBS questionnaires, and provided 11 biomarkers for their AL. Multiple linear regressions and logistic regression analysis were applied to examine the correlations between IEQ and AL or 8-OHdG and between AL or 8-OHdG and SBS, respectively. Our data revealed that the neuroendocrine system was correlated with CO₂, the difference between indoor and outdoor CO₂ levels (dCO₂), and the indoor-outdoor ratio of CO₂ (CO₂ I/O). Metabolic system effects were associated with illumination. The relationships between illumination, CO₂, dCO₂, CO₂ I/O and 8-OHdG were consistent with those and AL in specific systems. Furthermore, we found that risks for SBS syndromes were related with neuroendocrine and metabolic system of the AL. 8-OHdG was associated with eye dryness or irritation, eye tiredness and vomiting. We conclude that IEQ significantly influences AL and that AL can be a predictor for reporting SBS with information on system-specific effects.

Asthma related to workplace dampness and impaired work ability

PURPOSE

To examine the long-term effects on work ability among patients previously diagnosed with occupational asthma (OA) or work-exacerbated asthma (WEA) or symptoms in relation to workplace dampness.

METHODS

A questionnaire follow-up was used to study 1,098 patients (of whom 87 % were female) examined because of a suspected occupational respiratory disease caused by building dampness and mold. Self-rated work ability and early withdrawal from work were the two outcomes of the study. As determinants, we investigated the influence of the asthma diagnosis given in the initial examinations (OA or WEA), the number of persistent indoor air symptoms, and the psychosocial factors at work.

RESULTS

With a mean follow-up of 7.8 years, 40 % of the OA patients, under 65 years of age, were outside worklife versus 23 % of the WEA patients and 15 % of the patients with only upper respiratory symptoms at baseline. The diagnosis of OA was associated with a nearly sixfold risk for early withdrawal from work in a comparison with a reference group with upper respiratory symptoms. A perceived poor social climate at work and poor experiences with supervisory co-operation were associated with impaired work ability outcomes. Those with multiple, long-term indoor air symptoms considerably more often perceived their work ability to be poor when compared with those with less significant symptoms.

CONCLUSIONS

Adverse work ability outcomes are associated with asthma in relation to workplace dampness. The study raises the need for effective preventive measures in order to help workers with indoor air symptoms sustain their work ability.

Risk factors for the onset of nonspecific low back pain in office workers: a systematic review of prospective cohort studies

OBJECTIVE

The purpose of this study was to systematically review prospective cohort studies to identify risk factors for the onset of low back pain (LBP) in office workers.

METHODS

Online searches were conducted on PubMed, CINAHL Plus with full text, ScienceDirect, PEDro, ProQuest, and Scopus databases from 1980 to November 2011 using the following keywords: low back pain paired with risk or prognostic factors and office or computer or visual display unit (VDU) or visual display terminal (VDT). The methodological quality of each study was assessed using a 21-item checklist, which was divided into 2 parts: the internal validity (11 items) and descriptive quality (10 items) of studies. Strength of evidence for risk factors associated with the development of nonspecific LBP was assessed by defining 5 levels of evidence based on the number of studies and the quality score of studies.

RESULTS

Eighteen full-text articles were identified, and 15 were excluded. A total of 3 articles were judged to meet the selection criteria and were included in the methodological quality assessment. Risk factors were divided into 3 groups: individual, work-related physical, and work-related psychosocial risk factors. There was strong evidence that history of LBP is a predictor of the onset of LBP. Limited evidence was found that the combination of postural risk factors and job strain is associated with the onset of LBP.

CONCLUSION

After review of 3 high-quality prospective studies on the association between risk factors and the onset of nonspecific LBP in office workers, few risk factors were found to predict the onset of LBP in office workers.

Subjective Estimation of the Quality of Life in Relation to Neuroticism

It is generally agreed that personality variables have a relatively consistent influence on the subjective estimation of different situations in everyday life and the way people react to them. The aim of this review was to summarise our previously published findings on the relationship between subjective estimation of one's quality of life and the personality trait neuroticism-emotional stability. We used theWHO Quality of Life - BREFor SF-36 questionnaires for the assessment of the quality of life, Cornell Index for the assessment of neuroticism, and The Social Readjustment Rating Scale for the evaluation of common stressors. Our results have shown that more emotionally stable participants (lower neuroticism) perceive their life better in quality and are more satisfied with their work environment. In addition, our results support the findings from other studies that women have higher neuroticism and lower quality of life scores than men.

Upper respiratory impairment in restorers of cultural heritage

BACKGROUND

There is a paucity of data regarding respiratory health in restorers of cultural heritage or similar occupations, such as visual artists or museum workers, although they are exposed to a complex mixture of various respiratory hazards.

AIMS

To evaluate atopy and respiratory health parameters, including bronchial and nasal non-specific reactivity, in restorers and conservators of cultural heritage (restorers).

METHODS

Fifty-six restorers and 62 controls provided general data and data on ever experienced rhinitic or asthma-like symptoms, spirometry, non-specific bronchial and nasal responsiveness to histamine, skin prick testing to common inhalational allergens and serum total IgE levels.

RESULTS

Spirometry values were in the range of normal values in 55 of 56 restorers and did not differ significantly from those in control subjects. However, restorers had more than two times higher prevalence of nasal hyper-responsiveness (NHR), with 2.3 times higher risk of NHR compared to controls [95% confidence interval (CI): 1.4-3.6, P < 0.001]. The risk of NHR was slightly reduced by increasing age (odds ratio 0.95, 95% CI: 0.91-0.99, P < 0.05). NHR was not associated with gender, smoking status, bronchial hyperresponsiveness (BHR), upper or lower respiratory symptoms or atopy status.

CONCLUSIONS

Compared with controls, the studied group of workers occupationally exposed to respiratory hazards during restoration/conservation activities had no deterioration of lung function but had an increased non-specific nasal responsiveness that was not correlated with upper and lower respiratory symptoms, BHR or atopy. The relationship of this finding to future clinical outcome should be investigated in a longitudinal study.

Symptoms prevalence among office workers of a sealed versus a non-sealed building: associations to indoor air quality

OBJECTIVES

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.