Effects of occupant behaviors on perceived dormitory air quality and sick building syndrome symptoms among female college students.

We performed a cross-sectional survey of 2143 female students in a university in Tianjin, China regarding perceived air quality (PAQ) and sick building syndrome (SBS) symptoms in the student dormitory. The prevalence of general, mucosal, and skin symptoms was 22.1%, 21.9%, and 26.3%, respectively. The three most prevalent PAQ complaints were "dry air" (48.9% often), "stuffy odor" (18.2%), and "other unpleasant odors" (5.1%), and they were significant risk factors for 11-12 out of 12 SBS symptoms (adjusted odds ratios [AOR]: 1.6-5.8). Survey data of 1471 undergraduates, whose dorms were of uniform layout and furnishing, were used to further investigate the influences of occupancy level and occupant behaviors on PAQ and SBS symptoms. Frequent use of air freshener/perfume was a significant risk factor for "dry air," less frequent room cleaning and higher occupancy density were significant risk factors for "stuffy odor," and less natural ventilation was a significant risk factor for both "stuffy odor" and "pungent odor." These factors were also significantly associated with some SBS symptoms. In particular, the use of air freshener/perfume exhibited a significant dose-response pattern with "fatigue" (sometimes: AOR 1.3; often: AOR 2.0) and with "irritated, stuffy, or runny nose" (sometimes: AOR 1.6; often: AOR 2.2).

Associations between indoor environment and lifestyles and sick building syndrome symptoms among adults in Taiyuan and Urumqi of China.

The complex and uncertain causes of sick building syndrome (SBS) have become one of the most challenging and hot issues worldwide. Studies on the correlation between indoor environment and SBS based on local characteristics are relatively limited in China. We studied typical SBS risk factors related to the indoor environment and lifestyle in two northern Chinese cities. The study population was drawn from parents of pre-school children in randomized daycare centers in Taiyuan, Shanxi, and Urumqi, Xinjiang, China (N = 6838). Data on SBS and indoor environment were obtained from cross-sectional questionnaires. Odds ratios (OR) were estimated by multilevel logistic regression and adjusted using gender, atopy, own smoking, home size, and dampness index. Results showed that location, homeownership, year of construction completion, changes in the indoor environment (new furniture and decorations), and changes in indoor air (smoking, burning mosquito repellent and incense, cooking fuels including electricity, natural gas, coal, and wood) might contribute to different levels of SBS in Chinese adults, including eye, nasal, throat, dermal symptoms, and headache and tiredness. The results of the subgroup analysis suggest city and gender differences in susceptibility. Daily cleaning, window opening, and improved ventilation effectively improved SBS. People should improve their indoor environment and lifestyles based on sensitivity factors, gender, and geographic characteristics to reduce SBS risks.

A high environmental composite quality factor score was associated with the risk of sick building syndrome among adults in northeast China.

OBJECTIVES: Epidemiological evidence regarding the association between the combination of indoor and outdoor neighborhood pollution and sick building syndrome (SBS) among adults is limited and inconsistent. A cross-sectional study was conducted to investigate the association between the environmental composite quality factor score and SBS among adults. METHODS: This study included 2594 females and 666 males aged 18-77 years enrolled from the Northeast China. The environmental composite quality factor score was computed based on factors potentially associated with SBS risk, including the outdoor neighborhood pollution sources (the housing on the street, the presence of pollutants within 100 m of the house (gutters, garbage stations, noise, chemical pollution, and dust pollution), and the presence of arterial roads, factories, and chimneys) and indoor pollution sources (redecoration, clean fuel used for heating/cooking, cooking oil fume (COF) outside kitchen, using of mosquito coil or repellent, and using of incense). We performed multivariate logistic regression analysis to calculate the odds ratios (ORs) and 95% confidence intervals (95%CIs) between environmental composite quality factor score, indoor pollution composite factor score, outdoor neighborhood pollution composite factor score, and SBS adjustment for covariates. Further, we also did the stratified analysis and constructed a weighted score to verify the results. RESULTS: Compared with the lowest environmental composite quality factor score, the ORs of the highest scores were: 1.58 (95% CI, 1.20-2.27, Ptrend = 0.001) for general symptoms; 1.73 (95% CI, 1.35-2.23, Ptrend < 0.001) for mucosal symptoms and 1.75 (95% CI, 1.34-2.29, Ptrend < 0.001) for dermal symptoms and 1.81 (95% CI, 1.36-2.42, Ptrend < 0.001) for all of the three symptoms. We also observed similar patterns with the using of weighted scores and stratified analysis. CONCLUSION: Higher exposure to indoor pollution sources and outdoor pollution sources near the residence may be associated with a higher risk of SBS in adults in northeast China.

Indoor air quality and sick building syndrome in a university setting: a case study in Greece.

The perceived Indoor Air Quality (IAQ), the prevalence of Sick Building Syndrome (SBS) symptoms and its contributing risk factors were assessed in a university during the period of the economic crisis in Greece. Data was collected from 613 employees via questionnaires. Hierarchical linear regression analysis was performed. The most prevalent perceived IAQ complaints were 'Dust and dirt' (63.2%), 'Room temperature too low' (24.9%) and 'Varying room temperature' (24.4%). The most frequently reported SBS symptom was 'Fatigue' (34.1%). The prevalence of General, Mucosal and Dermal symptoms was 40.8%, 19.8% and 8.1%, respectively. Several contributing risk factors were identified, such as IAQ Discomfort Scale, atopy, sleep problems, female, exposure to biological and chemical agents, PC-use, Psychosocial Work Scale and job satisfaction. Poor perceived IAQ and high prevalence of SBS symptoms were reported from the university staff in a temperate climate country. SBS seemed to be multifactorial.

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.

Evaluation of the relationship between sick building syndrome complaints among hospital employees and indoor environmental quality.

BACKGROUND: Sick building syndrome (SBS) is defined as a condition occurring in people who live or work in a modern building and who suffer from complaints such as headache, fatigue, lack of concentration, and irritation of the skin and mucous membranes. OBJECTIVES: The aim of this study is to examine the complaints associated with SBS in the employees of our hospital and evaluate the relationship between the characteristics of the work environment and the complaints of SBS. METHODS: 890 workers participated in the study. The complaints of the participants were rated and the sum of all complaints was recorded as the Total Complaint Score (TCS). The mean TCS of the participants was compared according to demographic characteristics and work environment characteristics. RESULTS: The most common complaints among the employees were fatigue (40%), and general muscle and joint pain (31.4%). There was a statistically significant difference in TCS according to the position (p < 0.001). The mean TCS was significantly higher in females [13 (0-81)] than in males [6 (0-59)] (p < 0.001). The mean TCS increased with the presence of odor, new wall paint, the presence of fungus/ mold on walls, and the presence of rotting/mold smell (p < 0.001, for all). TCS positively correlated with stress level, social relationship, noise level, comfort, cleanliness, number of employees in the same room, presence of odor, new wall paint, presence of rotting/mold, and use of chemical materials for cleaning in the room (p < 0.001, for all), and negatively correlated with room size and number of windows (p = 0.006, p < 0.001, respectively). DISCUSSION: The present study found that the female gender, a high level of education, a high level of stress, a low level of social relationships and work environment characteristics were associated with the complaints of SBS among the employees. Accordingly, we believe that hospital management should be informed in order for the managers to take precautions and make new regulations.

Lifestyle behaviors and home and school environment in association with sick building syndrome among elementary school children: a cross-sectional study.

BACKGROUND: Sick building syndrome (SBS) refers to the combination of symptoms experienced by occupants of specific building characteristics. This study investigated the associations of children's lifestyle behaviors, allergies, home, and school environment with SBS symptoms. METHODS: A total of 4408 elementary school children living in Sapporo City, Japan participated in this study. SBS was determined on parental answers to MM080 standardized school questionnaires on symptoms that were weekly experienced by these children, and if the symptom is attributed to their home or school environment. The Japanese version of the International Study of Asthma and Allergies in Childhood questionnaire was used to assess wheeze, rhino-conjunctivitis, and eczema. A logistic regression analysis was conducted to evaluate the associations between SBS symptoms and variables by controlling the potential confounders (gender, grade, school, and parental history of allergies). A stepwise backward elimination was conducted to assess independent variables related to SBS. RESULTS: Participants revealed mucosal (6.9%), skin (2.0%), and general (0.8%) symptoms. The presence of one or more allergy was associated with increased mucosal and skin symptoms. Children who skipped breakfast, displayed faddiness (like/dislike of food), had constipation, have insufficient sleep, did not feel refreshed after sleep, and lacked deep sleep showed significantly high odds ratios with SBS symptoms. The stepwise analysis showed faddiness for mucosal symptoms and not feeling refreshed after sleep for mucosal and skin symptoms, whereas constipation and lacking deep sleep for general symptoms were independent variables in increasing the symptoms. We found no significant relationship between SBS in children and schools. Considering children's home, old building, no ventilation, wall-to-wall carpet, and heavy nearby traffic were associated with elevated mucosal symptom, while living in a multifamily home increased general symptoms. Home dampness was an independent variable in increasing all SBS symptoms. CONCLUSIONS: Allergies and lifestyle behaviors were associated with increased SBS in children, including skipping breakfast, displaying faddiness, constipation, insufficient sleep, not feeling refreshed after sleep, and the lack of deep sleep. Further, dampness at home was associated with increase in all SBS symptoms. Lifestyle (e.g., eating and sleeping habits) and home (i.e., dampness) improvements might alleviate SBS symptoms in children.

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.

Sick building syndrome and associated risk factors among the population of Gondar town, northwest Ethiopia.

BACKGROUND: Sick building syndrome (SBS) consists of a group of mucosal, skin, and general symptoms temporally related to residential and office buildings of unclear causes. These symptoms are common in the general population. However, SBS symptoms and their contributing factors are poorly understood, and the community associates it with bad sprits. This community-based cross-sectional study was, therefore, conducted to assess the prevalence and associated factors of SBS in Gondar town. METHODS: A community-based cross-sectional study was conducted from March to April 2017. A total of 3405 study subjects were included using multistage and systematic random sampling techniques. A structured questionnaire and observational checklists were used to collect data. SBS was assessed by 24 building-related symptoms and confirmed by five SBS confirmation criteria. Multivariable binary logistic regression analysis was used to identify factors associated with SBS on the basis of adjusted odds ratio (AOR) with 95% confidence interval (CI) and p < 0.05. The Hosmer and Lemeshow goodness of fit test was used to check model fitness, and variance inflation factor (VIF) was also used to test interactions between variables. RESULTS: The prevalence of SBS in Gondar town was 21.7% (95% CI = 20.3-23.0%). Of this, the mucosal symptoms account for 64%, the general symptoms account for 54%, and the skin symptoms account for 10%. From study participants who reported SBS symptoms, 44% had more than one symptom. Headache (15.7%), asthma (8.3%), rhinitis (8.0%), and dizziness (7.5%) were the commonest reported symptoms. SBS was significantly associated with fungal growth in the building [AOR = 1.25, 95% CI = (1.05, 1.49)], unclean building [AOR = 1.26, 95% CI = (1.03, 1.55)], houses with no functional windows [AOR = 1.35, 95% CI = (1.12, 1.63)], houses with no fan [AOR = 1.90, 95% CI = (1.22, 2.96)], utilization of charcoal as a cooking energy source [AOR = 1.40, 95% CI = (1.02, 1.91)], cooking inside the living quarters [AOR = 1.31, 95% CI = (1.09, 1.58)], and incensing and joss stick use [AOR = 1.48, 95% CI = (1.23, 1.77)]. CONCLUSION: The prevalence of SBS in Gondar town was high, and significant proportion of the population had more than one SBS symptom. Headache, asthma, rhinitis, and dizziness were the commonest reported SBS symptoms. Fungal growth, cleanliness of the building, availability of functional windows, availability of fan in the living quarters, using charcoal as a cooking energy source, cooking inside the quarters, and incensing habit or joss stick use were identified as factors associated with SBS. Improving the sanitation of the living environment and housekeeping practices of the occupants is useful to minimize the prevalence of SBS.

Relationship between sick building syndrome and indoor air quality among hospital staff.

BACKGROUND: Sick building syndrome (SBS) is defined as a condition occurring in those who live or work in a modern building and who suffer from symptoms such as headache, fatigue, lack of concentration and irritation of the skin and mucous membranes. OBJECTIVES: The aim of this study was to evaluate the relationship between personal characteristics, environmental factors and the prevalence of SBS among the secretaries working in a hospital. METHOD: In this cross-sectional study, questionnaires were administered to all secretaries who were working in Kutahya hospital in January and March 2018. The questionnaire used in the study included the sociodemographic characteristics of the participants and the question form "MM 040 NA Hospital" to evaluate SBS symptoms. These symptoms were the clinical symptoms reported by the secretaries as a result of exposure to factors within the hospital. Temperature, humidity, carbon dioxide concentration, light intensity and noise level were measured in the indoor environment of the hospital. Chi square test, Spearman's correlation coefficient and logistic regression models were used in the analysis of data. RESULTS: The study was completed with 177 people, 61.6% women, and the mean age was 30.14±5.7. The prevalence of SBS was found to be 20.9%. The risk of SBS was found to be 2.9 times higher for females, 2.8 times higher for individuals who described the working environment as dusty, 2.6 times higher for subjects complaining of stuffy "bad" air, dry air and an unpleasant odour. All measurements were found to be within acceptable limits. The risk of SBS was found to be 1.2 times higher with increases in the measured noise level, and 2.1 times higher with increased carbon dioxide (CO2) concentrations. CONCLUSION: The factors impacting the risk of experiencing SBS were determined. Bearing these factors in mind, we think that hospital administrations should be informed about arrangements and measures that will improve the quality of the internal environment of the hospital.

Protein profiles of nasal lavage fluid from individuals with work-related upper airway symptoms associated with moldy and damp buildings.

Upper airway irritation is common among individuals working in moldy and damp buildings. The aim of this study was to investigate effects on the protein composition of the nasal lining fluid. The prevalence of symptoms in relation to work environment was examined in 37 individuals working in two damp buildings. Microbial growth was confirmed in one of the buildings. Nasal lavage fluid was collected from 29 of the exposed subjects and 13 controls, not working in a damp building. Protein profiles were investigated with a proteomic approach and evaluated by multivariate statistical models. Subjects from both workplaces reported upper airway and ocular symptoms. Based on protein profiles, symptomatic subjects in the two workplaces were discriminated from each other and separated from healthy controls. The groups differed in proteins involved in inflammation and host defense. Measurements of innate immunity proteins showed a significant increase in protein S100-A8 and decrease in SPLUNC1 in subjects from one workplace, while alpha-1-antitrypsin was elevated in subjects from the other workplace, compared with healthy controls. The results show that protein profiles in nasal lavage fluid can be used to monitor airway mucosal effects in personnel working in damp buildings and indicate that the profile may be separated when the dampness is associated with the presence of molds.

Health Benefits of Green Public Housing: Associations With Asthma Morbidity and Building-Related Symptoms.

OBJECTIVES: We examined associations of several health outcomes with green and conventional low-income housing, where the prevalence of morbidities and environmental pollutants is elevated. METHODS: We used questionnaires and a visual inspection to compare sick building syndrome (SBS) symptoms and asthma-related morbidity among residents in multifamily units in Boston, Massachusetts, between March 2012 and May 2013. Follow-up was approximately 1 year later. RESULTS: Adults living in green units reported 1.35 (95% confidence interval [CI] = 0.66, 2.05) fewer SBS symptoms than those living in conventional (control) homes (P < .001). Furthermore, asthmatic children living in green homes experienced substantially lower risk of asthma symptoms (odds ratio [OR] = 0.34; 95% CI = 0.12, 1.00), asthma attacks (OR = 0.31; 95% CI = 0.11, 0.88), hospital visits (OR = 0.24; 95% CI = 0.06, 0.88), and asthma-related school absences (OR = 0.21; 95% CI = 0.06, 0.74) than children living in conventional public housing. CONCLUSIONS: Participants living in green homes had improved health outcomes, which remained consistent over the study period. Green housing may provide a significant value in resource-poor settings where green construction or renovation could simultaneously reduce harmful indoor exposures, promote resident health, and reduce operational costs.

Prevalence and risk factors associated with nonspecific building-related symptoms in office employees in Japan: relationships between work environment, Indoor Air Quality, and occupational stress.

A nationwide cross-sectional study of 3335 employees was conducted in 320 offices in Japan to estimate the prevalence of building-related symptoms (BRSs) and determine the risk factors related to work environment, Indoor Air Quality, and occupational stress. Data were collected through self-administered questionnaires. The prevalences of general symptoms, eye irritation, and upper respiratory symptoms were 14.4%, 12.1%, and 8.9%, respectively. Multiple logistic regression analyses revealed that eye irritation was significantly associated with carpeting [odds ratio (OR), 1.73; 95% confidence interval (CI), 1.24-2.41], coldness perception (OR, 1.28; 95% CI, 1.13-1.45), and air dryness perception (OR, 1.61; 95% CI, 1.42-1.82). General symptoms were significantly associated with unpleasant odors (OR, 1.37; 95% CI, 1.13-1.65), amount of work (OR, 1.24; 95% CI, 1.06-1.45), and interpersonal conflicts (OR, 1.44; 95% CI, 1.23-1.69). Upper respiratory symptoms were significantly associated with crowded workspaces (OR, 1.36; 95% CI, 1.13-1.63), air dryness perception (OR, 2.07; 95% CI, 1.79-2.38), and reported dustiness on the floor (OR, 1.39; 95% CI, 1.16-1.67). Although psychosocial support is important to reduce and control BRSs, maintaining appropriate air-conditioning and a clean and uncrowded workspace is of equal importance.

Exposure to formaldehyde, nitrogen dioxide, ozone, and terpenes among office workers and associations with reported symptoms.

PURPOSE: To compare exposure to formaldehyde, nitrogen dioxide, ozone and terpenes among office workers with and without sick building syndrome and the odds ratio for exposure. Are there significant differences? METHODS: In this cross-sectional study of office workers, we investigated the associations between exposure to formaldehyde, nitrogen dioxide, ozone, α-pinene, and D-limonene using a case-control analysis. Data on perceived general, mucosal, and skin symptoms were obtained by questionnaires. Personal exposure measurements of the compounds were performed among cases and controls, and the odds ratios for exposures to the substances, both singly and in combination, were investigated. RESULTS: Exposures varied for formaldehyde between 0.23 and 45 µg/m(3), nitrogen dioxide between 0.26 and 110 µg/m(3), ozone between <16 and 165 µg/m(3), α-pinene between 0.2 and 170 µg/m(3), and D-limonene between 0.8 and 1,400 µg/m(3). No consistent differences in exposure odds ratios were found between cases and controls or for individual symptoms.

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.

Use of personalized ventilation for improving health, comfort, and performance at high room temperature and humidity.

UNLABELLED: The effect of personalized ventilation (PV) on people's health, comfort, and performance in a warm and humid environment (26 and 28°C at 70% relative humidity) was studied and compared with their responses in a comfortable environment (23°C and 40% relative humidity). Thirty subjects participated in five 4-h experiments in a climate chamber. Under the conditions with PV, the subjects were able to control the rate and direction of the supplied personalized flow of clean air. Subjective responses were collected through questionnaires. During all exposures, the subjects were occupied with tasks used to assess their performance. Objective measures of tear film stability, concentration of stress biomarkers in saliva, and eye blinking rate were taken. Using PV significantly improved the perceived air quality (PAQ) and thermal sensation and decreased the intensity of Sick Building Syndrome (SBS) symptoms to those prevailing in a comfortable room environment without PV. Self-estimated and objectively measured performance was improved. Increasing the temperature and relative humidity, but not the use of PV, significantly decreased tear film quality and the concentration of salivary alpha-amylase, indicating lower mental arousal and alertness. The use of PV improved tear film stability as compared to that in a warm environment without PV. PRACTICAL IMPLICATIONS: In practice, the supply of clean, cool, and less humid air by PV at each workstation will make it possible to raise room temperatures above the upper comfortable limit suggested in the present standards without adversely affecting the occupants' health [Sick Building Syndrome (SBS) symptoms], comfort (thermal and perceived air quality), and performance. This may lead to energy savings.

Onset of mucosal, dermal, and general symptoms in relation to biomarkers and exposures in the dwelling: a cohort study from 1992 to 2002.

UNLABELLED: We examined the associations between biomarkers of allergy and inflammation, indoor environment in dwellings, and incidence and remission of symptoms included in the sick building syndrome (SBS) and changes in the home environment of 452 adults who were followed from 1992 to 2002 within the Uppsala part of the European Community Respiratory Health Survey (ECRHS). The 10-year incidence (onset) of general, mucosal, and dermal symptoms was 8.5%, 12.7%, and 6.8%, respectively. Dampness or indoor molds at baseline was a predictor of incidence of general (relative risk [RR] = 1.98), mucosal (RR = 2.28), and dermal symptoms (RR = 1.91). Women had higher incidence of general (RR = 1.74) and mucosal symptoms (RR = 1.71). Indoor painting increased the incidence of general symptoms (RR = 1.62). Bronchial responsiveness (BR), eosinophil counts in blood, total IgE and eosinophilic cationic protein (ECP) in serum at baseline were predictors of incidence of SBS. At follow-up, BR, total IgE, and C-reactive protein (CRP ) were associated with increased incidence of SBS. Moreover, subjects with doctor-diagnosed asthma at baseline had a higher incidence of general (RR = 1.65) and mucosal symptoms (RR = 1.97). In conclusion, female gender, dampness or indoor molds, indoor painting, and biomarkers of allergy and inflammation were associated with a higher incidence of SBS symptoms, in particular mucosal symptoms. PRACTICAL IMPLICATIONS: The focus in Sweden on indoor environment issues over the last few decades has resulted in improvements in dwellings, and reduced tobacco smoking, which could be beneficial for public health. Reducing dampness and molds in the dwelling place is another important way of reducing occurrence of SBS symptoms in the general adult population. The association between the incidence of SBS symptoms and clinical biomarkers of allergy and inflammation suggests a common etiology between inflammatory diseases, including asthma, rhinitis, and SBS. Lastly, good agreement between self-reported and clinically diagnosed atopy indicates that questionnaire data on atopy can be used in epidemiological studies.

Size-resolved emission rates of airborne bacteria and fungi in an occupied classroom.

UNLABELLED: The role of human occupancy as a source of indoor biological aerosols is poorly understood. Size-resolved concentrations of total and biological particles in indoor air were quantified in a classroom under occupied and vacant conditions. Per-occupant emission rates were estimated through a mass-balance modeling approach, and the microbial diversity of indoor and outdoor air during occupancy was determined via rDNA gene sequence analysis. Significant increases of total particle mass and bacterial genome concentrations were observed during the occupied period compared to the vacant case. These increases varied in magnitude with the particle size and ranged from 3 to 68 times for total mass, 12-2700 times for bacterial genomes, and 1.5-5.2 times for fungal genomes. Emission rates per person-hour because of occupancy were 31 mg, 37 × 10(6) genome copies, and 7.3 × 10(6) genome copies for total particle mass, bacteria, and fungi, respectively. Of the bacterial emissions, ∼18% are from taxa that are closely associated with the human skin microbiome. This analysis provides size-resolved, per person-hour emission rates for these biological particles and illustrates the extent to which being in an occupied room results in exposure to bacteria that are associated with previous or current human occupants. PRACTICAL IMPLICATIONS: Presented here are the first size-resolved, per person emission rate estimates of bacterial and fungal genomes for a common occupied indoor space. The marked differences observed between total particle and bacterial size distributions suggest that size-dependent aerosol models that use total particles as a surrogate for microbial particles incorrectly assess the fate of and human exposure to airborne bacteria. The strong signal of human microbiota in airborne particulate matter in an occupied setting demonstrates that the aerosol route can be a source of exposure to microorganisms emitted from the skin, hair, nostrils, and mouths of other occupants.

Antimicrobial efficacy and longevity of silver+zeolite incorporating preinsulated ducts installed in real healthcare settings.

OBJECTIVE: The values of microbial growth in the air exiting from the heating, ventilation and air conditioning (HVAC) ducts treated with silver/zeolite have been shown to be lower than those in the air coming out the traditional metal ones. This study aims to verify how long this antimicrobial activity lasts. METHODS: All the tests were performed according to US ASTM E2180-01 and ISO-JIZ 22196 standards. Samples of aluminum cladding panels of different thickness and incorporating silver-zeolite were tested in order to verify their thickness depending antibacterial activity. The same kind of linings samples were analyzed after a simulated and accelerated ageing process. Ag-zeolite incorporating HVAC duct panels linings were tested after years from their installation, in order to verify the maintenance of their bactericidal power during time. RESULTS AND CONCLUSIONS: For laminates containing different amounts of silver+Zeolite it was shown that also in panels with minimum thickness tested, the lowest germicidal effect (GE) found was still very good (GE of 5,76 ULog10). After their wearing and tearing the antimicrobial activity tended to increase passing from 7.2081 to 8.29922 LogUnits in panels 80 microns thick. For still hospital working aluminium foils incorporating Silver/Zeolite on panels installed through 2006 and 2008, the antimicrobial action of zeolite was still firmly present even after two years and three years.The germicidal effect standards were maintained even during time on constant values between 7.477 and 7.086 LogUnits. The persistence of bactericidal efficacy of Ag+zeolite treatment in all the materials used for the construction of HVAC ductworks can be confirmed.

Moldy buildings, health of their occupants and fungal prevention.

Microscopic fungi are important biological pollutants in the indoor environment, they are spread generally: on building materials, carpets, ceiling tiles, insulations, any surfaces, wallpapers, or in heating, ventilation, and air conditioning systems. Molds are able to grow on any materials, as long as moisture and oxygen are available. Exposure to fungi in indoor environments (esp. in water-damaged buildings) can cause adverse health effects, such as allergy, asthma, hypersensitivity pneumonia, mucous membrane irritation, different toxic effects, or even mycoses (in immunocompromised individuals) - alone or in combination. As serious adverse health effects could be caused antifungal prevention is an absolute need.This review article summarizes the occurrence of fungi in the indoor environment of buildings and their contribution to occupants´ health problems, and preventive measures against molds (Tab. 1, Fig. 1, Ref. 48).