Sick Building Symptoms Research Articles

Indoor air quality and sick-building syndrome at a metro station in Tianjin, China

Metro systems play a crucial role in public transportation worldwide. Given that metro stations are unique built environments with a significant volume of daily commuters, ensuring a satisfactory air quality in these spaces becomes paramount. This study involved measurements of indoor air quality (IAQ), staff satisfaction, particulate matter (PM) chemical composition, and heavy metal health risks at a typical metro station in Tianjin over two seasons. Although the air exchange rate was sufficient to maintain a CO2 concentration less than 1000ppm, the proportion of staff reporting no sick-building symptoms decreased from 83% in spring to 25% in winter. An average mass concentration of PM with an aerodynamic diameter smaller than 2.5μm (PM2.5) of 68.0±42.2μg/m3 and an average PM1 mass concentration of 51.8±33.3μg/m3 were observed on the platform in winter. PM2.5 contained more metal in winter than in spring. PM2.5 in winter contained more metal in winter than in spring. With a lower relative humidity in winter, the coefficient of friction between railway wheels and rails increased, thus increasing particle emission. The carcinogenic risk of Cr on the platform was unacceptable. Moreover, the health risks induced by Ba should be investigated. The findings indicate that PM control at metro stationss, particularly on platforms in winter, should be emphasized.

Indoor PM2.5, home environmental factors and lifestyles are related to sick building syndrome among residents in Nanjing, China

Indoor PM2.5, home environmental factors and lifestyles are related to sick building syndrome among residents in Nanjing, China

Classroom microbiome, functional pathways and sick-building syndrome (SBS) in urban and rural schools - Potential roles of indoor microbial amino acids and vitamin metabolites

Sick building symptoms (SBS) are defined as non-specific symptoms related to indoor exposures, including mucosal symptoms in eye, nose, throat, and skin, and general symptoms as headache and tiredness. Indoor microbial composition is associated with SBS symptoms, but the impact of microbial functional genes and potential metabolic products has not been characterized. We conducted a shotgun microbial metagenomic sequencing for vacuum dust collected in urban and rural schools in Shanxi province, China. SBS symptoms in students were surveyed, and microbial taxa and functional pathways related to the symptoms were identified using a multi-level linear regression model. SBS symptoms were common in students, and the prevalence of ocular and throat symptoms, headache, and tiredness was higher in urban than in rural areas (p < 0.05). A significant higher microbial α-diversity was found in rural areas than in urban areas (Chao1, p = 0.001; ACE, p = 0.002). Also, significant variation in microbial taxonomic and functional composition (β-diversity) was observed between urban and rural areas (p < 0.005). Five potential risk Actinobacteria species were associated with SBS symptoms (p < 0.01); students in the classrooms with a higher abundance of an unclassified Geodermatophilaceae, Geodermatophilus, Fridmanniella luteola, Microlunatus phosphovorus and Mycetocola reported more nasal and throat symptoms and tiredness. Students with a higher abundance of an unclassified flavobacteriaceae reported fewer throat symptoms and tiredness. The abundance of microbial metabolic pathways related to the synthesis of B vitamins (biotin and folate), gamma-aminobutyric acid (GABA), short-chain fatty acids (SCFAs), and peptidoglycan and were protectively (negatively) associated with SBS symptoms (FDR < 0.05). The result is consistent with human microbiota studies, which reported that these microbial products are extensively involved in immunological processes and anti-inflammatory effects. This is the first study to report the functional potential of the indoor microbiome and the occurrence of SBS, providing new insights into the potential etiologic mechanisms in chronic inflammatory diseases.

Towards a holistic approach for assessing the impact of IEQ on satisfaction, health, and productivity

ABSTRACT While there is broad evidence of the impact of tangible factors (i.e. room temperature, indoor air quality) on work well-being and productivity, the objective measurement of intangible factors (i.e. ergonomics and privacy) is still an under-researched subject. A holistic approach to indoor environmental quality (IEQ) has been developed in this study by combining the research dimensions of IEQ factors (tangible vs. intangible), outcome (workplace satisfaction, health, productivity), method (subjective vs. objective assessment) and impact (direct vs. indirect effects), and it has been tested in a laboratory (n = 180). The main findings are that (i) workplace satisfaction, health and productivity are more strongly affected by intangible factors than by tangible ones, (ii) impaired privacy leads to sick building symptoms and less creativity, (iii) negative self-assessment impairs objective performance in the form of a self-fulfilling prophecy, while (iv) personality traits correlate differently with ergonomics and privacy. Hence, a holistic IEQ approach that also considers interrelations between the research dimensions is beneficial for creating supportive workplace designs.

Working Conditions and Sick Building Syndrome among Health Care Workers in Vietnam.

Background: Little is known about risk factors for sick building symptoms (SBS) among health care workers (HCWs) who often face the workload, exposure to chemicals, and biological contaminants in the workplace. This study aims to evaluate the correlation between SBS and the symptoms among HCWs. Methods: A total of 207 HCWs were recruited in a large hospital-based cross-sectional survey between March and June 2017, southern Vietnam. Face-to-face interviews were conducted for collecting data on demographics, SBS-related symptoms, working environments, and conditions. Indoor environmental conditions were measured. SBS scores, ranging from 0 to 24, were determined by a sum of the scores of general symptoms, mucosal irritation, and skin symptoms; multivariate regression analyses and the Lindeman, Merenda, and Gold (LMG) test were used to investigate the predictors and its impact on the SBS. Results: A mean SBS score was 9.7 (range: 1–21). Compared with males, females were more likely to report higher SBS scores (10.2 vs. 7.9, p < 0.001). Being female, atopy, varying temperature room, stuffy “bad” air dust, and dirt had higher SBS scores of 2.0; 1.8; 1.7; 1.9; 3.8, respectively. LMG test showed that dust and dirt, and stuffy “bad” air were the predominant risk factors for SBS. Conclusions: Our study reveals that working conditions are important and significantly associated with SBS. Taken together with our findings, the working condition criteria approach trained for architects, builders, owners, and maintenance of the building is highly recommended for indoor air quality improvement. Furthermore, larger-sample studies about working condition are urgently needed to better manage SBS.

Sick building symptoms among hospital workers associated with indoor air quality and personal factors

This study assesses the interior air quality and infective factors in a hospital in Turkey to provide data about air quality to protect hospital workers. This study measured indoor air quality in eight different locations in a hospital, including particulate matter (PM2.5 and PM1), carbon dioxide, carbon monoxide, temperature, humidity and microbiological matter. The highest PM2.5 and PM1 concentrations were in emergency service, and the highest CO2 was measured in the paediatric clinic. The poor interior air quality results are the most important cross-sectional data. For all participants, the prevalence of eye, upper respiratory tract, lower respiratory tract, skin and non-specific sick building syndrome symptoms were 23.0%, 40.7%, 22.5%, 36.3% and 63.7%, respectively. When sick building syndrome symptoms and environmental factors were investigated, skin symptoms increased 1.82 times in areas with stagnant air flow (p = 0.046; OR = 1.823; 95% CI: 1.010–3.290). Non-specific symptoms increased 2.17 times in locations with dry indoor air (p = 0.039; OR = 2.176; 95% CI: 1.041–4.549). Hospital workers are exposed to conditions that may increase the risk of a variety of sick building syndrome symptoms. Although the air quality measurements were not above the recommended limits in the hospital, long-term exposures should be considered for those experiencing sick building syndrome-related symptoms.

The impact of working in a green certified building on cognitive function and health

Thirty years of public health research have demonstrated that improved indoor environmental quality is associated with better health outcomes. Recent research has demonstrated an impact of the indoor environment on cognitive function. We recruited 109 participants from 10 high-performing buildings (i.e. buildings surpassing the ASHRAE Standard 62.1-2010 ventilation requirement and with low total volatile organic compound concentrations) in five U.S. cities. In each city, buildings were matched by week of assessment, tenant, type of worker and work functions. A key distinction between the matched buildings was whether they had achieved green certification. Workers were administered a cognitive function test of higher order decision-making performance twice during the same week while indoor environmental quality parameters were monitored. Workers in green certified buildings scored 26.4% (95% CI: [12.8%, 39.7%]) higher on cognitive function tests, controlling for annual earnings, job category and level of schooling, and had 30% fewer sick building symptoms than those in non-certified buildings. These outcomes may be partially explained by IEQ factors, including thermal conditions and lighting, but the findings suggest that the benefits of green certification standards go beyond measureable IEQ factors. We describe a holistic "buildingomics" approach for examining the complexity of factors in a building that influence human health.

BARRIER OF VENTILATION MODES TO ACHIEVE A BALANCE ENVIRONMENT IN REFURBISHED PRESCHOOLS

The preschool education is compulsory to children in Malaysia. This regulation has encouraged more premises to be refurbished as a preschool building. This paper examines the pupils’ absenteeism and the prevalence of Sick Building Symptoms (SBS) initiated in congested private preschool with different ventilation. The study analysed data from the attendance record of 10 classrooms and the questionnaire surveys administered to 151 parents about their children health symptoms once they were leaving the schools building. Indoor Carbon Dioxide (CO2) measured as indicator of the problems. Questions on SBS used 5-point likert scale with symptoms concern on nose, eye, head, throat, skin, breath and tiredness. The descriptive and chi-square test applied to obtain the association of SBS and ventilation strategies in the classrooms. With quantitative and qualitative explanation, the unhealthy environment in refurbished pre-schools explained respiratory symptoms and higher rates of absenteeism frequently reported in air-conditioning (AC) classrooms due to concentrations of CO2 exceeded 1000 ppm. These symptoms show there were weaknesses in ventilation performance and environment in the selected preschools. Further analyses on objective measurements in future research are strongly recommended.

The Prevelence of SBS and Absenteeism among Children in Urban Refurbished Private Preshools

The preschool education is compulsory to children in Malaysia. This regulation has encouraged more premises to be refurbished as a pre-school building. This paper examines the pupils’ absenteeism and the prevalence of Sick Building Symptoms (SBS) initiated in congested private preschool with different ventilation strategies. The study analysed data from the attendance record of 10 classrooms and the questionnaire surveys administered to 151 parents about their children health symptoms once they were leaving the schools building. Questions on SBS used 5-point likert scale with symptoms concern on nose, eye, head, throat, skin, breath and tiredness. The descriptive and chi-square test applied to obtain the association of SBS and ventilation strategies in the classrooms. With quantitative and qualitative explanation, the unhealthy environment in refurbished pre-schools explained. Running nose, coughing and sore throat frequently reported in air-conditioning (AC) classrooms. The higher absent rate found in AC classrooms. These symptoms show there were weaknesses in ventilation performance and environment in the selected preschools. Further analyses on objective measurements in future research are strongly recommended.

Organophosphate and phthalate esters in indoor air: a comparison between multi-storey buildings with high and low prevalence of sick building symptoms

An extensive study has been conducted on the prevalence of organophosphorous flame retardants/plasticizers and phthalate ester plasticizers in indoor air. The targeted substances were measured in 45 multi-storey apartment buildings in Stockholm, Sweden. The apartment buildings were classified as high or low risk with regard to the reporting of sick building symptoms (SBS) within the project Healthy Sustainable Houses in Stockholm (3H). Air samples were taken from two to four apartments per building (in total 169 apartments) to facilitate comparison within and between buildings. Association with building characteristics has been examined as well as association with specific sources by combining chemical analysis and exploratory uni- and multivariate data analysis. The study contributes to the overall perspective of levels of organophosphate and phthalate ester in indoor air enabling comparison with other studies. The results indicated little or no difference in the concentrations of the target substances between the two risk classifications of the buildings. The differences between the apartments sampled within (intra) buildings were greater than the differences between (inter) buildings. The concentrations measured in air ranged up to 1200 ng m(-3) for organophosphate esters and up to 11 000 ng m(-3) for phthalate esters. Results in terms of sources were discerned e.g. PVC flooring is a major source of benzylbutyl phthalate in indoor air.

A new multiple regression model to identify multi-family houses with a high prevalence of sick building symptoms “SBS”, within the healthy sustainable house study in Stockholm (3H)

The aim was to develop a new model to identify residential buildings with higher frequencies of "SBS" than expected, "risk buildings". In 2005, 481 multi-family buildings with 10,506 dwellings in Stockholm were studied by a new stratified random sampling. A standardised self-administered questionnaire was used to assess "SBS", atopy and personal factors. The response rate was 73%. Statistical analysis was performed by multiple logistic regressions. Dwellers owning their building reported less "SBS" than those renting. There was a strong relationship between socio-economic factors and ownership. The regression model, ended up with high explanatory values for age, gender, atopy and ownership. Applying our model, 9% of all residential buildings in Stockholm were classified as "risk buildings" with the highest proportion in houses built 1961-1975 (26%) and lowest in houses built 1985-1990 (4%). To identify "risk buildings", it is necessary to adjust for ownership and population characteristics.

Annual transition and seasonal variation of indoor air pollution levels of 2-ethyl-1-hexanol in large-scale buildings in Nagoya, Japan

2-Ethyl-1-hexanol (2E1H) is a possible causative chemical for sick building symptoms; however, thus far, we do not have a clear understanding of the indoor air pollution levels caused by it. In this study, first, airborne 2E1H concentrations were measured during summer and winter from 2004 to 2007 in 67 rooms of 56 large-scale buildings in Nagoya, Japan, in order to show the seasonal variation of indoor air pollution levels of 2E1H. Then, a follow-up survey was conducted in five rooms of five buildings for more than 2 years in order to establish the annual transition of their 2E1H indoor air pollution levels. 2E1H was found to be one of the predominant volatile organic compounds in the indoor air of large-scale buildings. Its geometric mean concentration was significantly higher during summer (55.4 microg/m3) than during winter (13.7 microg/m3) (p < 0.01), although there was a significant difference in the concentrations among the buildings. High 2E1H concentrations may have been caused by high emission rates of 2E1H from floors, because of the hydrolysis of di(2-ethylhexyl) phthalate in polyvinyl chloride flooring materials or of adhesives containing 2-ethylhexyl moieties. Follow-up observations showed little decrease in the indoor air 2E1H concentrations from one year to the next, although they did show seasonal fluctuations, with an evident increase in concentrations during summer and an evident decrease during winter.

Development of Competition Enzyme-Linked Immunosorbent Assay for Determination of Formaldehyde in Serum

Sick-building symptoms associated with indoor air volatile organic compounds, including formaldehyde in new or newly remodeled houses, have been increasingly highlighted, and are known as sick house syndrome in Japan. We developed a competition enzyme-linked immunosorbent assay for measuring formaldehyde in serum. The specificity of the antiserum generated with formaldehyde-rabbit serum albumin conjugates and the application to the detection of formaldehyde in serum were evaluated. The antiserum selectively reacted with formaldehyde conjugated to rabbit, human, rat and bovine-serum albumins, but not with unconjugated albumins. The quantitative working range of formaldehyde-human serum albumin conjugates was from 0.5 to 500 ng/well.

Indoor air pollution by 2-ethyl-1-hexanol in non-domestic buildings in Nagoya, Japan

2-Ethyl-1-hexanol is a possibly causative chemical in sick building symptoms, although 2-ethyl-1-hexanol has received little attention as a hazardous substance in studies on indoor air pollution. Airborne 2-ethyl-1-hexanol concentrations were measured from 2002 to 2004 in 99 rooms of 42 non-domestic buildings in Nagoya, Japan. The diffusive sampling method is effective for the measurement of a low level of 2-ethyl-1-hexanol in indoor air. The geometric mean (geometric standard deviation) of 2-ethyl-1-hexanol concentrations was 16.5 (5.4) microg m(-3) in indoor air and 1.9 (2.2) microg m(-3) in outdoor air. The maximum concentration of 2-ethyl-1-hexanol in indoor air and outdoor air was 2709 microg m(-3) and 12.4 microg m(-3), respectively. Fewer rooms in a small number of new buildings showed high concentrations of 2-ethyl-1-hexanol, while low concentrations were observed in many rooms of these buildings as well as the other new buildings. The room-to-room concentrations of 2-ethyl-1-hexanol in each building exhibited a wide variation. The geometric mean of the 2-ethyl-1-hexanol concentrations was significantly higher for indoor air than for outdoor air (p < 0.01). The correlation of the 2-ethyl-1-hexanol concentrations between indoor and outdoor air was not significant. Mechanical ventilation was effective in the temporary reduction of indoor 2-ethyl-1-hexanol level. These results suggest that the predominant source of 2-ethyl-1-hexanol was indoor areas.

Meeting Report: Investigating Indoor Air

Americans spend about 85–95% of their time indoors, and in recent years, the indoor environment and its potential effects on health have become the subject of increasing research attention. Seeking to explore the existing knowledge and stimulate new ideas for action, the nation’s top public health officer convened a gathering of more than 300 experts from government, academia, the building materials and design industries, and public interest groups for a two-day conference in January 2005. The Surgeon General’s Workshop on Healthy Indoor Environment began with presentations of the scientific evidence that exposure to polluted indoor air is making many people sick. Those exposures include chemicals (such as volatile organic compounds and pesticides), biological agents, other particulates, environmental tobacco smoke, excessive dampness, and poor ergonomic, noise, thermal, and lighting conditions. Eileen Storey, director of the University of Connecticut Center for Indoor Environments, said surveys indicate that on average 40–55% of office occupants experience some degree of so-called sick building symptoms (such as headache, cough, wheezing, and fatigue) on a weekly basis. Speakers discussed the 2004 Institute of Medicine report Damp Indoor Spaces and Health, an exhaustive literature review which concluded that excessive indoor dampness and fungal growth are consistently and convincingly associated with respiratory health effects, including asthma. The report delineated research needs in the area, including reproducible, validated measurement and risk assessment methods. Peyton Eggleston, a professor of pediatrics and immunology at the Johns Hopkins School of Medicine, said, “We [also] need an intervention study that will take a damp building, remediate it, and show in a rigorous scientific way that there is both a measurable environmental impact and a measurable health impact.” There was also a consistent call to implement good practices based on current knowledge, and to express the benefits of improving indoor air quality in terms of economic value, so building owners, operators, and occupants can appreciate that such investments make bottom-line sense. Storey presented estimates from the September 2002 American Journal of Public Health that improving indoor air may save businesses $5–75 billion annually through fewer sick building symptoms, communicable respiratory diseases, allergies, and asthma attacks, with concomitant gains in productivity. “If we calculate it in those ways,” said Storey, “people will immediately say, ‘It’s worth it to run my building in a way that people are not going to get sick.’” Several participants cited the need for well-defined standards of what constitutes a healthy indoor environment, perhaps including a building rating system. Several government agencies represented at the workshop currently have research initiatives involving the indoor environment. Surgeon general Richard Carmona urged more collaboration, not only among federal agencies, but also in research and intervention partnerships with academia and the building professions. “The issue of a healthy indoor environment is key to improving the health of the American people,” he said. “Clearly the time has come for action in this area.”

2‐Ethyl‐1‐hexanol in Indoor Air as a Possible Cause of Sick Building Symptoms

Journal of Occupational HealthVolume 44, Issue 3 p. 186-191 Case StudyFree Access 2-Ethyl-1-hexanol in Indoor Air as a Possible Cause of Sick Building Symptoms Michihiro Kamijima, Michihiro Kamijima Department of Occupational and Environmental Health, Nagoya University Graduate School of MedicineSearch for more papers by this authorKiyoshi Sakai, Kiyoshi Sakai Nagoya City Public Health Research InstituteSearch for more papers by this authorEiji Shibata, Eiji Shibata Department of Medical Technology, Nagoya University School of Health SciencesSearch for more papers by this authorTetsuya Yamada, Tetsuya Yamada Department of Occupational and Environmental Health, Nagoya University Graduate School of MedicineSearch for more papers by this authorSeiichiro Itohara, Seiichiro Itohara Department of Occupational and Environmental Health, Nagoya University Graduate School of MedicineSearch for more papers by this authorHiroyuki Ohno, Hiroyuki Ohno Nagoya City Public Health Research InstituteSearch for more papers by this authorRitsuko Hayakawa, Ritsuko Hayakawa Department of Environmental Dermatology, Nagoya University School of MedicineSearch for more papers by this authorMariko Sugiura, Mariko Sugiura Department of Environmental Dermatology, Nagoya University School of MedicineSearch for more papers by this authorKenichi Yamaki, Kenichi Yamaki Second Department of Internal Medicine, Nagoya University School of MedicineSearch for more papers by this authorYasuhiro Takeuchi, Yasuhiro Takeuchi Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine Research Center for Radiation Emergency Medicine, National Institute of Radiological Sciences, JapanSearch for more papers by this author Michihiro Kamijima, Michihiro Kamijima Department of Occupational and Environmental Health, Nagoya University Graduate School of MedicineSearch for more papers by this authorKiyoshi Sakai, Kiyoshi Sakai Nagoya City Public Health Research InstituteSearch for more papers by this authorEiji Shibata, Eiji Shibata Department of Medical Technology, Nagoya University School of Health SciencesSearch for more papers by this authorTetsuya Yamada, Tetsuya Yamada Department of Occupational and Environmental Health, Nagoya University Graduate School of MedicineSearch for more papers by this authorSeiichiro Itohara, Seiichiro Itohara Department of Occupational and Environmental Health, Nagoya University Graduate School of MedicineSearch for more papers by this authorHiroyuki Ohno, Hiroyuki Ohno Nagoya City Public Health Research InstituteSearch for more papers by this authorRitsuko Hayakawa, Ritsuko Hayakawa Department of Environmental Dermatology, Nagoya University School of MedicineSearch for more papers by this authorMariko Sugiura, Mariko Sugiura Department of Environmental Dermatology, Nagoya University School of MedicineSearch for more papers by this authorKenichi Yamaki, Kenichi Yamaki Second Department of Internal Medicine, Nagoya University School of MedicineSearch for more papers by this authorYasuhiro Takeuchi, Yasuhiro Takeuchi Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine Research Center for Radiation Emergency Medicine, National Institute of Radiological Sciences, JapanSearch for more papers by this author First published: 29 November 2002 https://doi.org/10.1539/joh.44.186Citations: 38 Correspondence to: M. Kamijima, Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume44, Issue3May 2002Pages 186-191 ReferencesRelatedInformation

HEALTH AND PRODUCTIVITY GAINS FROM BETTER INDOOR ENVIRONMENTS AND THEIR RELATIONSHIP WITH BUILDING ENERGY EFFICIENCY

▪ Abstract Theoretical considerations and empirical data suggest that existing technologies and procedures can improve indoor environments in a manner that significantly increases productivity and health. The existing literature contains moderate to strong evidence that characteristics of buildings and indoor environments significantly influence rates of communicable respiratory illness, allergy and asthma symptoms, sick building symptoms, and worker performance. Whereas there is considerable uncertainty in the estimates of the magnitudes of productivity gains that may be obtained by providing better indoor environments, the projected gains are very large. For the United States, the estimated potential annual savings and productivity gains are $6 to $14 billion from reduced respiratory disease, $1 to $4 billion from reduced allergies and asthma, $10 to $30 billion from reduced sick building syndrome symptoms, and $20 to $160 billion from direct improvements in worker performance that are unrelated to health. Productivity gains that are quantified and demonstrated could serve as a strong stimulus for energy efficiency measures that simultaneously improve the indoor environment.

Relating Sick Building Symptoms to Environmental Conditions and Worker Characteristics

Abstract Recent concern has centered on “sick buildings” in which there has been an unusually high percentage of health complaints by the building's occupants. Typically, these symptoms are thought to be tied to indoor air quality characteristics, such as high levels of respirable particles or volatiles, thermal conditions, etc. In addition, recent studies have drawn connections between “sick building syndrome” (SBS) symptoms and non-environmental variables, i.e., personal and occupational factors. This paper presents a brief review of a study by Hedge et al. (1995) and additional analyses of their data. In a study of 27 air-conditioned office buildings, Hedge et al. measured nine indoor environmental conditions at various locations within each building and concurrently questioned workers on sixteen SBS symptoms and a number of other personal factors. The additional analyses presented in this paper attempt to draw formal statistical connections between SBS symptoms and both personal worker characteristics and indoor air pollutants simultaneously. The analyses were based on symptom severity response variables whic include information not only on the frequency with which an individual experienced a symptom, but also on how much the symptom disrupted the individual's work. Results from sixteen linear mixed effects models indicate that significant predictors are primarily personal and occupational in nature rather than environmental. For a number of the symptoms, additional variability attributable to buildings exists. However, any physical explanation of this variability remains unclear.

Sick-building symptoms in office workers in northeastern France: a pilot study.

To verify that sick building symptoms are present in north-eastern France office workers; to try to identify new confounding factors. The design was that of a cross-sectional study with control group. We studied with the same methods the personnel of an air-conditioned building (n=425), and of a naturally ventilated building (n=351). Air temperature and humidity, bacterial and fungal densities were measured by the same technical staff in the two buildings. A standard questionnaire on irritative and respiratory symptoms, personal and family history, and lifestyle was completed by the participants. In univariate analysis, exposure to air-conditioning was associated with an increased prevalence of symptoms (odds ratios-OR-between 1.54 and 2.84). A significant increase in sickness absence was also found among subjects working in air-conditioned offices. As a series of factors were suspected to interfere with these associations, logistic regression was applied. This method confirmed exposure to be an independent determinant of 7 symptoms, and also identified two determinants not previously described: a family history of respiratory diseases and "do-it-yourself' activities. we found the sick building symptoms to be present in a group of French office workers exposed to air-conditioning. We confirmed the influence of a number of confounding factors and described two further confounders - do-it-yourself activities at home and a history of familial respiratory disease.

$30 Billion Per Year Saved Through Increased Worker Productivity

There is strong evidence that characteristics of buildings and indoor environments significantly influence rates of respiratory disease, allergy and asthma symptoms, sick building symptoms, and worker performance. Theoretical considerations, and limited empirical data, suggest that existing technologies and procedures can improve indoor environments in a manner that significantly increases health and productivity. At present, one can develop only crude estimates of the magnitude of productivity gains that may be obtained by providing better indoor environments; however, the projected gains are very large.