Health and Indoor Climate Complaints of 7043 office Workers in 61 Buildings in the Netherlands

During the winter of 1988/1989, the relationships between the prevalence of work-related health and indoor climate complaints and a number of building, management, workplace and personal characteristics have been investigated in a study in more than 60 office buildings located throughout the Netherlands. To collect the information, a questionnaire was prepared on health and indoor climate complaints and personal and workplace characteristics. A checklist was used to obtain information on building characteristics More than 7000 questionnaires were completed by the regular users of the buildings investigated. The results showed that the prevalence of symptoms was higher in air-conditioned buildings than in naturally or mechanically ventilated buildings. some other variables were also related with most work-related complaints after adjustment for selected management, personal, workplace and job characteristics. These included gender, work satisfaction in general, presence of allergies and/or respiratory symptoms, and personal control over temperature at the workplace. No differences were found in symptom prevalences between buildings with spray and steam humidification. The combination of air-conditioning and humidification did not lead to further increases in the prevalence of complaints as compared to buildings with only airconditioning or only humidification.     

Association of subjective health symptoms with indoor air quality in European office buildings: The OFFICAIR project

The aim of this study was to explore the association between the building-related occupants’ reported health symptoms and the indoor pollutant concentrations in a sample of 148 office rooms, within the framework of the European OFFICAIR research project. A large field campaign was performed in 37 office buildings among eight countries, which included (a) 5-day air sampling of volatile organic compounds (VOCs), aldehydes, ozone, and NO₂ (b) collection of information from 1299 participants regarding their personal characteristics and health perception at workplace using online questionnaires. Stepwise and multilevel logistic regressions were applied to investigate associations between health symptoms and pollutant concentrations considering personal characteristics as confounders. Occupants of offices with higher pollutant concentrations were more likely to report health symptoms. Among the studied VOCs, xylenes were associated with general (such as headache and tiredness) and skin symptoms, ethylbenzene with eye irritation and respiratory symptoms, a-pinene with respiratory and heart symptoms, d-limonene with general symptoms, and styrene with skin symptoms. Among aldehydes, formaldehyde was associated with respiratory and general symptoms, acrolein with respiratory symptoms, propionaldehyde with respiratory, general, and heart symptoms, and hexanal with general SBS. Ozone was associated with almost all symptom groups.     

Associations between indoor environment in residential buildings in wet and dry seasons and health of students in upper northern Thailand

We performed a repeated questionnaire study on home environment and health (six medical symptoms) in 1159 junior high school students (age 12.8 ± 0.7 years) in upper northern Thailand in wet and dry seasons. Data on outdoor temperature, relative humidity (RH), and air pollution were collected from nearest monitoring station. Odds ratios (OR) were calculated by multi-level logistic regression. Most common symptoms were rhinitis (62.5%), headache (49.8%), throat (42.8%), and ocular symptoms (42.5%). Ocular symptoms were more common at lower RH and rhinitis more common in dry season. Water leakage (28.2%), indoor mold (7.1%), mold odor (4.1%), and windowpane condensation (13.6%) were associated with all six symptoms (ORs: 1.3–3.5). Other risk factors included cat keeping, environmental tobacco smoke (ETS), other odor than mold odor, gas cooking, and cooking with biomass fire. Biomass burning inside and outside the home for other reasons than cooking was associated with all six symptoms (ORs: 1.5–2.6). Associations between home environment exposure and rhinitis were stronger in wet season. In conclusion, dampness-related exposure, windowpane condensation, cat keeping, ETS, gas cooking, and biomass burning can impair adolescent health in upper northern Thailand. In subtropical areas, environmental health effects should be investigated in wet and dry seasons.     

Phase 1 of the California Healthy Building Study: A Summary

Twelve public office buildings were selected for a study of relationships between worker's health symptoms and a number of building, workspace, job, and personal factors. Three buildings were naturally ventilated, three were mechanically ventilated, and six were air conditioned. Information on the prevalences of work-related symptoms, demographics, and job and personal factors were determined via a questionnaire completed by 880 occupants. Several indoor environmental parameters were measured. Logistic regression models were used to evaluate associations between symptom prevalences and features of the buildings, indoor environments, jobs, and personal factors. A substantial fraction of the occupants in these typical office buildings reported frequent work-related symptoms. The occupants of the mechanically ventilated and air conditioned buildings had sipifcantly more symptoms than occupants of the naturally ventilated buildings after adjustment for confounding factors. Increased prevalences of some symptoms were associated with several job and workspace factors including: presence of carpet, increased use of carbonless copy paper and photocopiers, space sharing, and distance from a window     

Dust exposure and lung function of workers in the brick and clay pottery factories in the Northeast of Thailand

This study aimed to determine the particulate matter concentrations (PM10) in workplace air and personal dust, and their effects on the respiratory health of exposed workers. The lung function of 449 exposed workers was examined. The concentration of PM10 in workplace air and personal dust exposure was measured. Spirometry was used to evaluate the lung function capacity included forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), forced expiratory volume ratio (FEV%) and peak expiratory flow rate (PEF). The forced expiratory flow at 25% to 75% of the FVC (FEF 25-75%) was determined. The PM10 concentration in workplace air (6 study sites) and personal dust (4 study sites) exceeded the standard (REL) of 0.12 mg/m3. The results of this study showed a decrease in the mean values and percent predicted value of FVC, FEV1, FEV1%, PEF and FEF 25-75%. The lung capacity of participants revealed that 24.50%, 4.45% and 7.13% had mildly, moderately restrictive and small airway disease. The respiratory symptoms were dyspnoea (22.49%), wheezing (10.69%), chest pain (10.69%) and chronic cough (2.90%). Factors influencing lung capacity included mask usage (Adj.OR: 0.44 CI: 0.25-0.79 p-value: 0.006) and chest pain (Adj.OR: 2.68 CI: 1.14-6.30 p-value: 0.024).     

Respiratory Symptoms and Housing Characteristics

A health and housing questionnaire was administered to children, ages 9-11, living in 24 communities in the United States and Canada. Logistic regression analysis examined the relationship between respiratory health symptoms (bronchitic, asthmatic and lower respiratory) and housing factors. The health risks (expressed as relative odds) were controlled for gender, parental asthma, parental chronic obstructive pulmonary disease and parental education, as well as between-city differences. Lower respiratory symptoms had significantly higher odds ratios reported in older homes (1.12), homes with smokers (1.24), air conditioners (1.14), air cleaners (1.37), and humidifiers (1.47). Home dampness (1.48) and the individual mold and water variables were all significantly associated with increased symptoms. Similar results were reported for bronchitic and asthmatic symptoms. While air conditioners and air cleaners were confounded with symptoms, humidifiers remained significant after controlling for childhood atopy.     

Personal Risk Factors Associated with Mucosal Symptom Prevalence in Office Workers

In 1989 the Madison Building of the Library of Congress was investigated to determine the source of occupant complaints about health symptoms and the indoor air quality. Questionnaires, distributed to all 3176 building occupants, assessed information on workstation characteristics, symptom occurrence, odors, thermal comfort, and demographic and health factors. Multivariate logistic regression analyses were conducted to assess personal risk factors associated with mucosal symptom reporting and reported sensitivity to irritants. Symptom prevalence was higher for women (odds ratio (OR) = 1.72, 95% confidence interval (CI) 1.40-2.10), those who reported being especially sensitive to irritants (OR = 1.57, 95% CI1.27-1.93), those with self-reported allergies, flu, or chest illness, and those who took frequent fresh air breaks. It was found that females and non-smokers and those reporting other adverse health effects tended to report sensitivity to irritants more frequently.     

Associations of perceived indoor environmental quality with stress in the workplace

Indoor environmental quality (IEQ) is a general indicator of the quality of conditions inside a building. We investigated associations of perceived IEQ including air quality, thermal comfort, noise, and light quality with stress at work and the extent to which workplace location modifies these associations. We recruited 464 full-time workers from four companies in Singapore. Data on socio-demographic characteristics, lifestyle/health-related factors, and workplace factors were collected through self-administered questionnaires. Perceived IEQ satisfaction scores of all four factors were collected using the validated OFFICAIR questionnaire. We fitted a logistic regression model to assess associations between each perceived IEQ score and stress at work, adjusting for potential confounders. The odds ratio for stress at work associated with a 1-unit increase in perceived air quality score was 0.88 (0.82-0.94), 0.89 (0.82-0.97) for thermal comfort, 0.93 (0.87-0.98) for noise, and 0.88 (0.82-0.94) for light quality. Significant associations were found in office and control rooms for all four perceived IEQ, except for thermal comfort in office rooms. Higher satisfaction levels of perceived air quality, thermal comfort, noise, and lighting, were significantly associated with a reduction in stress at work. Our findings could potentially provide a useful tool for environmental health impact assessment for buildings.     

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.     

Investigation of indoor chemical pollutants and perceived odor in an area with complaints of unpleasant odors

An uncomfortable smell was reported by employees of an IT office (information technological office) in a medical center. This problem started two years ago when the office was refurbished. The objectives of this study are to characterize the indoor air quality of this complaint area in terms of chemical pollutants and odor characteristics, and identify possible sources of this foul smell. Carbonyl chemicals and volatile organic compounds (VOCs) were investigated in this study, since these two groups are associated with odors and health effects. Additionally, the odor was evaluated by odor assessors (non-smokers) who recorded odor characters that appeared in offices. By comparing chemical measurements between complaint and non-complaint areas, calculating odor indices, and correlating odor and chemical measurements, we got results showing that a higher correlation coefficient is found between odor presence frequencies and VOC concentrations. Further investigating found nonanal and decanal are possible chemicals for malodors. The concentration levels of these two chemicals in the complaint area are higher than those in the non-complaint areas and exceeding odor thresholds. Possible sources of these long-chain aldehydes are formed during the oxidation degradations of fatty acids like linoleic acid, linolenic acid and oleic acid which are ingredients for many building products like linoleum and surface coating. In order to mitigate this malodor problem, extra and effective ventilation flow rate should be provided to reduce the concentrations of odorous chemicals and the precursors for these odorous chemicals.     

Molds in floor dust and building-related symptoms in adolescent school children

This stratified cross-sectional epidemiological study included 1053 school children aged 13-17 years. All pupils filled in a questionnaire on building-related symptoms and other relevant health aspects. The following exposure measurements were carried out: room temperature, CO2 level, and relative humidity; building characteristics including mold infestation were assessed, and dust was collected from floors, air, and ventilation ducts during a working day. Dust was examined for endotoxin level, and cultivated for viable molds. We did not find a positive association between building-related symptoms and extent of moisture and mold growth in the school buildings. Five of eight building-related symptoms were significantly and positively associated with the concentration of colony forming units of molds in floor dust: eye irritation, throat irritation, headache, concentration problems, and dizziness. After adjusting for different potentially confounding factors in separate analyses of each symptom, the above-mentioned associations between molds in dust and symptoms were still present, except for concentration problems. However, in none of the analyses was mold exposure the strongest covariate, being secondary to either asthma, hay fever, recent airway infection, or psychosocial factors.     

Effects of pollution from personal computers on perceived air quality, SBS symptoms and productivity in offices

In groups of six, 30 female subjects were exposed for 4.8 h in a low-polluting office to each of two conditions--the presence or absence of 3-month-old personal computers (PCs). These PCs were placed behind a screen so that they were not visible to the subjects. Throughout the exposure the outdoor air supply was maintained at 10 l/s per person. Under each of the two conditions the subjects performed simulated office work using old low-polluting PCs. They also evaluated the air quality and reported Sick Building Syndrome (SBS) symptoms. The PCs were found to be strong indoor pollution sources, even after they had been in service for 3 months. The sensory pollution load of each PC was 3.4 olf, more than three times the pollution of a standard person. The presence of PCs increased the percentage of people dissatisfied with the perceived air quality from 13 to 41% and increased by 9% the time required for text processing. Chemical analyses were performed to determine the pollutants emitted by the PCs. The most significant chemicals detected included phenol, toluene, 2-ethylhexanol, formaldehyde, and styrene. The identified compounds were, however, insufficient in concentration and kind to explain the observed adverse effects. This suggests that chemicals other than those detected, so-called 'stealth chemicals', may contribute to the negative effects. PRACTICAL IMPLICATIONS: PCs are an important, but hitherto overlooked, source of pollution indoors. They can decrease the perceived air quality, increase SBS symptoms and decrease office productivity. The ventilation rate in an office with a 3-month-old PC would need to be increased several times to achieve the same perceived air quality as in a low-polluting office with the PC absent. Pollution from PCs has an important negative impact on the air quality, not only in offices but also in many other spaces, including homes. PCs may have played a role in previously published studies on SBS and perceived air quality, where PCs were overlooked as a possible pollution source in the indoor environment. The fact that the chemicals identified in the office air and in the chamber experiments were insufficient to explain the adverse effects observed during human exposures illustrates the inadequacy of the analytical chemical methods commonly used in indoor air quality investigations. For certain chemicals the human senses are much more sensitive than the chemical methods routinely used in indoor air quality investigations. The adverse effects of PC-generated air pollutants could be reduced by modifications in the manufacturing process, increased ventilation, localized PC exhaust, or personalized ventilation systems.     

Associations of indoor carbon dioxide concentrations,air temperature,and humidity with perceived air quality and sick building syndrome symptoms in Chinese homes

The indoor environment influences occupants’ health. From March 1, 2018, to February 28, 2019, we continuously monitored indoor temperature (T), relative humidity (RH), and CO₂ concentration in bedrooms via an online system in 165 residences that covered all five climate zones of China. Meanwhile, we asked one specific occupant in each home to complete questionnaires about perceived air quality and sick building syndrome (SBS) symptoms at the end of each month. Higher CO₂ concentration was significantly associated with a higher percentage of perceived stuffy odor and skin SBS symptoms. Higher relative humidity was associated with higher percentage of perceived moldy odor and humid air, while lower RH was associated with a higher percentage of perceived dry air. Occupants who lived in residences with high RH were less likely to have mucosal and skin SBS symptoms (adjusted odds ratio (AOR): 0.73–0.78). However, the benefit of high humidity for perceived dry air and skin dryness symptoms is weaker if there is a high CO₂ concentration level.     

Dampness and mold in homes across China: Associations with rhinitis,ocular, throat and dermal symptoms,headache and fatigue among adults

We studied dampness and mold in China in relation to rhinitis, ocular, throat and dermal symptoms, headache and fatigue. A questionnaire study was performed in six cities including 36 541 randomized parents of young children. Seven self‐reported signs of dampness were evaluated. Multilevel logistic regression models were used to calculate odds ratios (ORs). Totally, 3.1% had weekly rhinitis, 2.8% eye, 4.1% throat and 4.8% skin symptoms, 3.0% headache and 13.9% fatigue. Overall, 6.3% of the homes had mold, 11.1% damp stains, 35.3% damp bed clothing, 12.8% water damage, 45.4% window pane condensation, 11.1% mold odor, and 37.5% humid air. All dampness signs were associated with symptoms (ORs from 1.2 to 4.6; P < 0.001), including rhinitis (ORs from 1.4 to 3.2; P < 0.001), and ORs increased by number of dampness signs. The strongest associations were for mold odor (ORs from 2.3 to 4.6) and humid air (ORs from 2.8 to 4.8). Associations were stronger among men and stronger in Beijing as compared to south China. In conclusion, dampness and mold are common in Chinese homes and associated with rhinitis and ocular, throat and dermal symptoms, headache and fatigue. Men can be more sensitive to dampness and health effects of dampness can be stronger in northern China.     

Allergic and Non-allergic Students' Perception of the Same High School Environment

Abstract The aim of the study was to describe how allergies and non-allergies perceive the same environment. All high school students in a town in southern Sweden were invited to answer a questionnaire concerning allergy, subjective symptoms, annoyance reactions and perception of the environment (response rate: 81%). The results show that only 45% of the students were non-allergic (n = 1,715). Since the symptom frequency among non-allergic students was normal, the schools were classified as healthy. However, compared to the non-allergic students, a higher percentage among the allergies suffered from symptoms every week, a lower percentage was satisfied with the air quality and the cleaning, and a higher percentage was bothered every week by temperature, stuffy/stale air, bad odor, passive smoke, bad lighting, noise, dust and dirt (ANOVA, P < 0.05). The findings could indicate that allergies note discomfort earlier than non-allergies by being more critical in general and especially critical to factors that could effect their health. The findings could also indicate that awareness of ones own sensitivity could lead to attention to different risk factors, which in turn could lead to stress/anxiety, which could make symptoms worse. The conclusion is that it is important to take allergy into consideration when the environment is assessed.     

A Prevalence Study Of The Sick Building Syndrome (SBS) And Facial Skin Symptoms In Office Workers

The prevalence of symptoms compatible with the Sick Building Syndrome (SBS) was measured in a questionnaire study among 4 943 office workers. An assessment of the relation between SBS symptoms and personal, physical and psychosocial exposure factors was made. In contrast to males, the majority of females were lower-grade staff Females reported annoyance from physical climate factors more often, both at work and at home. Males reported a better psychosocial situation than females. Female gender, asthmalrhinitis, paper and VDT work were related to an increased prevalence of SBS symptoms. The prevalence of facial skin symptoms increased markedly with the amount of VDT work. Psychosocial workload intensifid this relation. Inequalities in physical climate and psychosocial conditions associated with different positions held in the offices can be of importance for the increased occurrence of symptoms among females.     

Chloroanisoles may explain mold odor and represent a major indoor environment problem in Sweden

Indoor mold odor is associated with adverse health effects, but the microbial volatiles underlying mold odor are poorly described. Here, chloroanisoles were studied as potential key players, being formed by microbial metabolism of chlorophenols in wood preservatives. Using a three‐stage approach, we (i) investigated the occurrence of chloroanisoles in buildings with indoor air quality problems, (ii) estimated their frequency in Sweden, and (iii) evaluated the toxicological risk of observed chloroanisole concentrations. Analyses of 499 building materials revealed several chloroanisole congeners in various types of buildings from the 1950s to 1970s. Evaluation of Swedish records from this time period revealed three coinciding factors, namely an unprecedented nationwide building boom, national regulations promoting wood preservatives instead of moisture prevention, and use of chlorophenols in these preservatives. Chlorophenols were banned in 1978, yet analysis of 457 indoor air samples revealed several chloroanisole congeners, but at median air levels generally below 15 ng/m³. Our toxicological evaluation suggests that these concentrations are not detrimental to human health per se, but sufficiently high to cause malodor. Thereby, one may speculate that chloroanisoles in buildings contribute to adverse health effects by evoking odor which, enhanced by belief of the exposure being hazardous, induces stress‐related and inflammatory symptoms.     

The effect of housing characteristics and occupant activities on the respiratory health of women and children in Lao PDR

The paper presents the results of a study conducted into the relationship between dwelling characteristics and occupant activities with the respiratory health of resident women and children in Lao People's Democratic Republic (PDR). Lao is one of the least developed countries in south-east Asia with poor life expectancies and mortality rates. The study, commissioned by the World Health Organisation, included questionnaires delivered to residents of 356 dwellings in nine Districts in Lao PDR over a five month period (December 2005-April 2006), with the aim of identifying the association between respiratory health and indoor air pollution, in particular exposures related to indoor biomass burning. Adjusted odds ratios were calculated for each health outcome separately using binary logistic regression. After adjusting for age, a wide range of symptoms of respiratory illness in women and children aged 1-4 years were positively associated with a range of indoor exposures related to indoor cooking, including exposure to a fire and location of the cooking place. Among women, “dust always inside the house” and smoking were also identified as strong risk factors for respiratory illness. Other strong risk factors for children, after adjusting for age and gender, included dust and drying clothes inside. This analysis confirms the role of indoor air pollution in the burden of disease among women and children in Lao PDR.     

Risk factors for dissatisfaction with the indoor environment in open-plan offices: an analysis of COPE field study data

We applied binary logistic regression techniques to data collected from 779 participants in a field study of open-plan ('cubicle') offices conducted in nine buildings. Independent variables were physical conditions in the workplace, and dependent variables were derived from occupant satisfaction measures; personal characteristics were included as covariates. There was a significantly higher risk of dissatisfaction with privacy and acoustics (defined as being below the 20th percentile as opposed to being above the 80th percentile) associated with being in a small workstation, or being seated next to a window. A higher risk of dissatisfaction with ventilation was associated with being seated next to a window, temperatures substantially higher than the average neutral temperature, and a carbon dioxide concentration greater than 650 ppm. A higher risk of dissatisfaction with lighting was associated with panel heights greater than 66 inches (1.7 m), high reflected glare on computer screens, desktop illuminances outside 300-500 lux, desktop illuminance uniformity (min/max ratio) less than 0.5, and being in a workstation distant from a window. PRACTICAL IMPLICATIONS: We have demonstrated statistically significant relationships between indoor environment conditions in office spaces and environmental dissatisfaction risk. Although generally supported by prior research, not all of these risk factors are reflected in existing recommended practice documents for office design. Consideration of these findings in future revisions of such documents may be warranted.     

Multivariate evaluation of VOCs in buildings where people with non-specific building-related symptoms perceive health problems and in buildings where they do not

Volatile organic compounds (VOCs) were sampled in buildings where people with non-specific building-related symptoms perceive health problems and in buildings where they do not. In total, nine persons and 34 buildings were included in the study. The obtained VOC data was evaluated using multivariate methods, to investigate possible systematic differences in air quality of 'problem' and 'non-problem' buildings. All individual compounds were included as variables in a multivariate partial least squares (PLS) data analysis. 'Problem' and 'non-problem' buildings separated into two distinct groups, showing that air samples of the two groups of building were chemically different. PRACTICAL IMPLICATIONS: The study showed that there was an identifiable systematic difference in the collected VOC data between buildings causing and not causing problems for people with non-specific building-related symptoms (also called sick building syndrome, SBS). This is an important indication that even such volatile organic compounds that can be sampled by commonly used adsorbents are of importance for the presence of such symptoms. By coordination of procedures for sampling and analysis of VOCs in buildings between laboratories, to get large datasets and more general models, the method can become a useful diagnostic measure in evaluating indoor air and to identify chemical compounds and sources that contribute to SBS problems.