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.     

Ocular,nasal, dermal and respiratory symptoms in relation to heating,ventilation, energy conservation,and reconstruction of older multi-family houses

The aim was to study relationships between symptoms compatible with the sick building syndrome, type of heating and ventilation system, energy saving, and reconstruction in older dwellings. In Stockholm, 4815 inhabitants in 231 multi-family buildings built before 1961 were randomly selected, of whom 3241 participated (77%). Symptoms and personal factors were assessed by a postal questionnaire. Independent information on building characteristics, and energy saving measures was gathered from the building owners. Multiple logistic regression analysis was applied to calculate odds ratios (OR) adjusting for age, gender, hay fever, current smoking, population density, type of ventilation, type of heating system, and ownership of the building. Subjects in buildings with a mechanical ventilation system had less ocular and nasal symptoms (OR = 0.29-0.85). Heating by electric radiators, and wood heating was associated with an increase of most symptoms (OR = 1.18-1.74). In total, 48% lived in buildings that had gone through at least one type of reconstruction or energy saving remedies during the latest 10 years, including exchange of heating or ventilation system, and sealing measures (exchange of windows, sealing of window frames, roof/attic insulation, and phasade insulation). Energy saving was associated with both a decrease and increase of different symptoms. Major reconstruction of the interior of the building was associated with an increase of most symptoms (OR = 1.09-1.90), and buildings with more than one sealing measure had an increase of ocular, nasal symptoms, headache and tiredness (OR = 1.22-2.49). In conclusion, major reconstruction of the interior, direct heated electric radiators, wood heating, and multiple sealing of buildings were associated with an increase of some symptoms. The study supports the view that mechanical ventilation in dwellings is beneficial from a health point of view.     

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.     

Symptoms and Perceived Indoor Air Quality among Occupants of Houses and Apartments with Different Ventilation Systems

The purpose of the study was to evaluate the occurrence of symptoms and the perception of poor indoor air quality among the occupants of houses and apartments with different ventilation systems. The study population consisted of the 473 occupants of 242 dwellings in the Helsinki metropolitan area who responded to a self-administered questionnaire (response rate 93.1%) after a two-week period of indoor air quality measurements. The symptoms of interest were those often related to poor indoor air quality including dryness or itching of the skin; dryness, irritation or itching of the eyes; nasal congestion (“blocked nose”) nasal dry-ness; nasal discharge (“runny nose”); sneezing; cough; breathlessness; headache or migraine; and lethargy, weakness or nausea. Perception of coldness; warm-ness; draught; dryness; stuffiness; and sufficiency of air exchange was also requested. The age-standardized period prevalences of the symptoms and complaints were systematically more common among the occupants of the apartments than those of the houses. The occupants of the houses with natural ventilation seemed to have more symptoms and complaints than those with balanced ventilation. However, in the apartments with balanced ventilation the occupants reported, in general, more symptoms and complaints than those with natural ventilation.     

Pet keeping and dampness in the dwelling: associations with airway infections, symptoms, and physiological signs from the ocular and nasal mucosa

The aim was to utilize data from a study of occupational indoor environments to analyze symptoms and physiological signs in relation to the home environment. A medical investigation was performed at the workplace among university staff (n = 173) from four university buildings in Bergen, in March 2004. Tear film break up time (BUT) was measured by two methods. Nasal patency was measured by acoustic rhinometry. Nasal lavage fluid analysis (NAL) included eosinophilic cationic protein (ECP); myeloperoxidase (MPO), lysozyme and albumin. Atopy was assessed by total serum IgE and specific IgE (Phadiatop). Totally 21%, 21%, 18%, 11%, and 27% had weekly ocular, nasal, facial dermal symptoms, headache and tiredness, respectively, 15% had a damp dwelling, and 20% had a cat or dog. Multiple linear or logistic regressions were applied, controlling for age gender, smoking, and environmental factors. Building dampness was associated with increased NAL-lysozyme (P = 0.02) and an increase of airway infections [odd ratio (OR) = 3.14, P = 0.04]. Pet keeping was associated with difficulties to concentrate (OR = 5.10, P = 0.001), heavy headedness (OR = 4.35, P = 0.004), four more days with tiredness per month (P = 0.04), and less airway infections (OR = 0.32; P = 0.02). In conclusion, pet keeping was associated with more central nervous system (CNS)-symptoms but less airway infections. Dampness in the dwelling may have inflammatory effects on the airway mucosa, possibly mediated via increased infection proneness. PRACTICAL IMPLICATIONS: The main health focus on pet keeping has been allergen exposure. Our study indicates that effects on airway infections and other types of symptoms should also be considered. The findings support the view that measures should be taken to reduce building dampness in dwellings.     

Changes of symptoms, tear film stability and eosinophilic cationic protein in nasal lavage fluid after re-exposure to a damp office building with a history of flooding

The aim was to study health effects in office workers (N = 18) in a medical case book archive with dampness caused by flooding. They were first investigated in a building without dampness (exposure free for 10 days). Then all returned to the damp building, and were re-investigated after 2 days. We measured tear film break up time (BUT), nasal patency, biomarkers in nasal lavage (NAL), and dynamic spirometry. Both buildings had low CO(2) (380-600 ppm), low levels of respirable particles (8-10 microg/m(3)), and formaldehyde (5-7 microg/m(3)). The flooded building had slightly higher (149 ng/m(3) vs. 94 ng/m(3)) levels of microbial volatile organic compounds (MVOC). After 2 days of re-exposure, there was an increase of ocular (P < 0.001), nasal (P = 0.002), and throat symptoms (P < 0.001), dyspnea (P = 0.006), headache (P = 0.002), nausea (P = 0.04), and tiredness (P = 0.01). The median BUT decreased from 16 to 8 s (P = 0.003), and eosinophilic cationic protein (ECP) in NAL increased slightly (P = 0.04). A separate test of the weekday effect showed slight improvements, or no change of symptoms and signs from Monday to Wednesday. In conclusion, subjects previously exposed to building dampness had an increase of symptoms, reduced tear film stability, and signs of eosinophilic inflammation in the nasal mucosa after 2 days of re-exposure. PRACTICAL IMPLICATIONS: The study is in agreement with previous cross-sectional studies, suggesting that building dampness may cause mucosal irritation, general symptoms such as headache and tiredness, impaired tear film stability, and eosinophilic inflammation in the airway mucosa. From a preventive point of view, health consequences of water leakage and flooding should not be neglected. The measurements of molds and microbial volatile organic compounds could not identify any obvious exposure contrast between the damp building and the dry control building. This illustrates the limitations of air measurements of microbial exposures in damp buildings.     

Presence and variability of culturable bioaerosols in three multi-family apartment buildings with different ventilation systems in the Northeastern US

Bioaerosol concentrations in residential buildings located in the Northeastern US have not been widely studied. Here, in 2011-2015, we studied the presence and seasonal variability of culturable fungi and bacteria in three multi-family apartment buildings and correlated the bioaerosol concentrations with building ventilation system types and environmental parameters. A total of 409 indoor and 86 outdoor samples were taken. Eighty-five percent of investigated apartments had indoor-outdoor (I/O) ratios of culturable fungi below 1, suggesting minimal indoor sources of fungi. In contrast, 56% of the apartments had I/O ratios for culturable bacteria above 1, indicating the prominence of indoor sources of bacteria. Culturable fungi I/O ratios in apartments serviced by central heating, ventilation, and air-conditioning (HVAC) system were lower than those in apartments with window AC. The type of ventilation system did not have a significant effect on the presence of indoor culturable bacteria. A significant positive association was determined between indoor dew point (DP) levels and indoor culturable fungi (P < .001) and bacteria (P < .001), regardless of ventilation type. Also, residents in apartments with central HVAC did not experience extreme DP values. We conclude that building ventilation systems, seasonality, and indoor sources are major factors affecting indoor bioaerosol levels in residential buildings.     

Building-related respiratory symptoms can be predicted with semi-quantitative indices of exposure to dampness and mold

Using a semi-quantitative mold exposure index, the National Institute for Occupational Safety and Health (NIOSH) investigated 13 college buildings to examine whether building-related respiratory symptoms among employees are associated with environmental exposure to mold and dampness in buildings. We collected data on upper and lower respiratory symptoms and their building-relatedness, and time spent in specific rooms with a self-administered questionnaires. Trained NIOSH industrial hygienists classified rooms for water stains, visible mold, mold odor, and moisture using semi-quantitative scales and then estimated individual exposure indices weighted by the time spent in specific rooms. The semi-quantitative exposure indices significantly predicted building-related respiratory symptoms, including wheeze [odds ratio (OR) = 2.3; 95% confidence interval (CI) = 1.1-4.5], chest tightness (OR = 2.2; 95% CI = 1.1-4.6), shortness of breath (OR = 2.7; 95% CI = 1.2-6.1), nasal (OR = 2.5; 95% CI = 1.3-4.7) and sinus (OR = 2.2; 95% CI = 1.2-4.1) symptoms, with exposure-response relationships. We found that conditions suggestive of indoor mold exposure at work were associated with building-related respiratory symptoms. Our findings suggest that observational semi-quantitative indices of exposure to dampness and mold can support action to prevent building-related respiratory diseases. PRACTICAL IMPLICATIONS: Current air sampling methods have major limitations in assessing exposure to mold and other biological agents that may prevent the demonstration of associations of bioaerosol exposure with health. Our study demonstrates that semi-quantitative dampness/mold exposure indices, based solely on visual and olfactory observation and weighted by time spent in specific rooms, can predict existence of excessive building-related respiratory symptoms and diseases. Relative extent of water stains, visible mold, mold odor, or moisture can be used to prioritize remediation to reduce potential risk of building-related respiratory diseases. From a public health perspective, these observational findings justify action to correct water leaks and repair water damage in order to prevent building-related respiratory diseases. This approach can also be a basis for developing practical building-diagnostic tools for water-incursion.     

Building dampness and mold in European homes in relation to climate,building characteristics and socio‐economic status: The European Community Respiratory Health Survey ECRHS II

We studied dampness and mold in homes in relation to climate, building characteristics and socio‐economic status (SES) across Europe, for 7127 homes in 22 centers. A subsample of 3118 homes was inspected. Multilevel analysis was applied, including age, gender, center, SES, climate, and building factors. Self‐reported water damage (10%), damp spots (21%), and mold (16%) in past year were similar as observed data (19% dampness and 14% mold). Ambient temperature was associated with self‐reported water damage (OR=1.63 per 10°C; 95% CI 1.02‐2.63), damp spots (OR=2.95; 95% CI 1.98‐4.39), and mold (OR=2.28; 95% CI 1.04‐4.67). Precipitation was associated with water damage (OR=1.12 per 100 mm; 95% CI 1.02‐1.23) and damp spots (OR=1.11; 95% CI 1.02‐1.20). Ambient relative air humidity was not associated with indoor dampness and mold. Older buildings had more dampness and mold (P<.001). Manual workers reported less water damage (OR=0.69; 95% CI 0.53‐0.89) but more mold (OR=1.27; 95% CI 1.03‐1.55) as compared to managerial/professional workers. There were correlations between reported and observed data at center level (Spearman rho 0.61 for dampness and 0.73 for mold). In conclusion, high ambient temperature and precipitation and high building age can be risk factors for dampness and mold in homes in Europe.     

Microbial Cell Wall Constituents in Indoor Air and their Relation to Disease

Abstract This presentation reviews the relation between damp buildings, mold growth and symptoms and disease among persons living or working in such buildings. Epidemiological studies on these relationships date back to 1924 and at present there are almost 30 large-scale investigations. There is an almost general concordance between studies on the relation between damp buildings and symptoms of the airways. Most of the studies show also a relation between symptoms and reported or measured mold growth. The symptoms reported are remarkably similar in the different studies: nose or throat irritation, wheezing, dry cough and fatigue. It is suggested that this symptom profile reflects a non-specific airways inflammation and that antigen-mediated allergy is rare. Regarding agents capable of inducing airways inflammation, data on bacterial endotoxin demonstrate a causal relationship, whereas information on another microbial wall agent - (1→3)-β-D-glucan - is suggestive but not conclusive of a causal relationship. From a practical point of view, dampness and previous mold growth represent conditions in buildings where renovation should be undertaken, particularly if there are symptoms of airways inflammation among the occupants.     

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

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.     

Air filter materials, outdoor ozone and building-related symptoms in the BASE study

Used ventilation air filters have been shown to reduce indoor environmental quality and worker performance and increase symptoms, with effects stronger after reaction of filters with ozone. We analyzed data from the US EPA Building Assessment Survey and Evaluation (BASE) study to determine if ozone and specific filter media have interactive effects on building-related symptoms (BRS). We analyzed a subset of 34 buildings from the BASE study of 100 US office buildings to determine the separate and joint associations of filter medium [polyester/synthetic (PS) or fiberglass (FG)] and outdoor ozone concentration (above/below the median, 67.6 microg/m(3)) with BRS. Using logistic regression models and general estimating equations, we estimated odds ratios (ORs) and 95% confidence intervals for the association of filter medium, ozone, and filter medium x ozone with BRS. Relative to FG + low ozone, PS alone or high ozone alone, were each significantly (P < 0.05) associated only with fatigue/difficulty concentrating (ORs = 1.93 and 1.54, respectively). However, joint exposure to both PS + high ozone, relative to FG + low ozone, had significant associations with lower and upper respiratory, cough, eye, fatigue, and headache BRS (ORs ranged from 2.26 to 5.90). Joint ORs for PS + high ozone for lower and upper respiratory and headache BRS were much greater than multiplicative, with interaction P-values <0.10. Attributable risk proportion (ARP) estimates indicate that removing both risk factors might, given certain assumptions, reduce BRS by 26-62%. These findings suggest possible adverse health consequences from chemical interactions between outdoor ozone and PS filters in buildings. Results need confirmation before recommending changes in building operation. However, if additional research confirms causal relationships, ARP estimates indicate that appropriate filter selection may substantially reduce BRS in buildings, especially in high-ozone areas. PRACTICAL IMPLICATIONS: The results indicate that a better understanding of how filters interact with their environment is needed. While the mechanism is unknown and these findings need to be replicated, they indicate that the joint risk of BRS from polyester/synthetic filters and outdoor ozone above 67.6 microg/m(3) is much greater than the risk from each alone. These findings suggest potential reductions in BRS from appropriate selection of ventilation filter media or implementing strategies to reduce ozone entrained in building ventilation systems. If the relationships were found to be causal, filter replacement and ozone abatement should be undertaken.     

Two Moldy Day-care Centers: a Follow-up Study of Respiratory Symptoms and Infections

Abstract The aim was to study the respiratory symptoms among children exposed to indoor air molds in a day-care environment in Finland. Two day-care centers with a mold problem and two reference day-care centers were included in the study and the health data of the children were collected with a follow-up study of two periods. A total of 229 children 3-7 years old attended the day-care centers. During the first follow-up period, the children in the two day-care centers with mold problems had a significantly increased risk of sore throat, purulent and non-purulent nasal discharge, nasal congestion, hoarseness and common cold. During the second follow-up period, a significantly increased risk of purulent nasal discharge, nasal congestion, hoarseness and cough was observed. Upper respiratory tract symptoms, at least once during the study period, were more prevalent among the children attending mold-problem day-care centers. The mold-exposed children had such symptoms repeatedly or the symptoms were prolonged. In conclusion, in the mold-problem day-care centers, overall morbidity for respiratory symptoms and for common cold increased in comparison with the reference day-care centers.     

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.     

Dampness in buildings and health. Nordic interdisciplinary review of the scientific evidence on associations between exposure to "dampness" in buildings and health effects (NORDDAMP)

Several epidemiological investigations concerning indoor environments have indicated that "dampness" in buildings is associated to health effects such as respiratory symptoms, asthma and allergy. The aim of the present interdisciplinary review is to evaluate this association as shown in the epidemiological literature. A literature search identified 590 peer-reviewed articles of which 61 have been the foundation for this review. The review shows that "dampness" in buildings appears to increase the risk for health effects in the airways, such as cough, wheeze and asthma. Relative risks are in the range of OR 1.4-2.2. There also seems to be an association between "dampness" and other symptoms such as tiredness, headache and airways infections. It is concluded that the evidence for a causal association between "dampness" and health effects is strong. However, the mechanisms are unknown. Several definitions of dampness have been used in the studies, but all seems to be associated with health problems. Sensitisation to mites may be one but obviously not the only mechanism. Even if the mechanisms are unknown, there is sufficient evidence to take preventive measures against dampness in buildings.     

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

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

Indoor molds, bacteria, microbial volatile organic compounds and plasticizers in schools--associations with asthma and respiratory symptoms in pupils

We investigated asthma and atopy in relation to microbial and plasticizer exposure. Pupils in eight primary schools in Uppsala (Sweden) answered a questionnaire, 1014 (68%) participated. Totally, 7.7% reported doctor-diagnosed asthma, 5.9% current asthma, and 12.2% allergy to pollen/pets. Wheeze was reported by 7.8%, 4.5% reported daytime breathlessness, and 2.0% nocturnal breathlessness. Measurements were performed in 23 classrooms (May-June), 74% had <1000 ppm CO(2) indoors. None had visible mold growth or dampness. Mean total microbial volatile organic compound (MVOC) concentration was 423 ng/m(3) indoors and 123 ng/m(3) outdoors. Indoor concentration of TMPD-MIB (2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, Texanol) and TMPD-DIB (2,2,4-trimethyl-1,3-pentanediol diisobutyrate, TXIB), two common plasticizers, were 0.89 and 1.64 microg/m(3), respectively. MVOC and plasticizer concentration were correlated (r = 0.5; P < 0.01). Mold concentration was 360 cfu/m(3) indoors and 980 cfu/m(3) outdoors. At higher indoor concentrations of total MVOC, nocturnal breathlessness (P < 0.01) and doctor-diagnosed asthma (P < 0.05) were more common. Moreover, there were positive associations between nocturnal breathlessness and 3-methylfuran (P < 0.01), 3-methyl-1-butanol (P < 0.05), dimethyldisulfide (P < 0.01), 2-heptanone (P < 0.01), 1-octen-3-ol (P < 0.05), 3-octanone (P < 0.05), TMPD-MIB (P < 0.05), and TMPD-DIB (P < 0.01). TMPD-DIB was positively associated with wheeze (P < 0.05), daytime breathlessness (P < 0.05), doctor-diagnosed asthma (P < 0.05), and current asthma (P < 0.05). In conclusion, exposure to MVOC and plasticizers at school may be a risk factor for asthmatic symptoms in children. PRACTICAL IMPLICATIONS: Despite generally good ventilation and lack of visible signs of mold growth, we found an association between respiratory symptoms and indoor MVOC concentration. In addition, we found associations between asthmatic symptoms and two common plasticizers. The highest levels of MVOC, TMPD-MIB, and TMPD-DIB were found in two new buildings, suggesting that material emissions should be better controlled. As MVOC and plasticizers concentrations were positively correlated, while indoor viable molds and bacteria were negatively correlated, it is unclear if indoor MVOC is an indicator of microbial exposure. Further studies focusing on health effects of chemical emissions from indoor plastic materials, including PVC-floor coatings, are needed.     

Public health and economic impact of dampness and mold

The public health risk and economic impact of dampness and mold exposures was assessed using current asthma as a health endpoint. Individual risk of current asthma from exposure to dampness and mold in homes from W.J. Fisk, Q. Lei-Gomez & M.J. Mendell [(2007) Indoor Air, [corrected] 17, 284-296], and [corrected] asthma risks calculated from additional studies that reported the prevalence of dampness and mold in homes were used to estimate the proportion of US current asthma cases that are attributable to dampness and mold exposure at 21% (95% confidence internal 12-29%). An examination of the literature covering dampness and mold in schools, offices, and institutional buildings, which is summarized in the Appendix, suggests that risks from exposure in these buildings are similar to risks from exposures in homes. Of the 21.8 million people reported to have asthma in the USA, approximately 4.6 (2.7-6.3) million cases are estimated to be attributable to dampness and mold exposure in the home. Estimates of the national cost of asthma from two prior studies were updated to 2004 and used to estimate the economic impact of dampness and mold exposures. By applying the attributable fraction to the updated national annual cost of asthma, the national annual cost of asthma that is attributable to dampness and mold exposure in the home is estimated to be $3.5 billion ($2.1-4.8 billion). Analysis indicates that exposure to dampness and mold in buildings poses significant public health and economic risks in the USA. These findings are compatible with public policies and programs that help control moisture and mold in buildings. PRACTICAL IMPLICATIONS: There is a need to control moisture in both new and existing construction because of the significant health consequences that can result from dampness and mold. This paper demonstrates that dampness and mold in buildings is a significant public health problem with substantial economic impact.     

Symptoms, complaints, ocular and nasal physiological signs in university staff in relation to indoor environment - temperature and gender interactions

Symptoms, signs, perceptions, and objective measures were studied in university buildings. Two problem buildings with a history of dampness and complaints were compared with two control buildings. Health investigations among university staff were performed at the workplace (n = 173) including tear film stability [non-invasive break-up time (NIBUT) and self-reported break-up time (SBUT)], nasal patency (acoustic rhinometry), nasal lavage fluid analysis [NAL: eosinophil cationic protein (ECP), myeloperoxidase (MPO), lysozyme and albumin] and atopy by total serum IgE and IgE antibodies (Phadiatop). Exposure assessment included inspections, thermal and atmospheric climate at 56 points modelled for all work sites. Multiple regressions were applied, controlling for age and gender. Exposure differences between problem buildings and controls were small, and variations between rooms were greater. Workers in the problem buildings had more general and dermal symptoms, but not more objective signs than the others. Adjusted day NIBUT and SBUT increased at higher night air temperatures, with B (95% CI) 0.6 (0.04-1.2) and 1.3 (-0.02 to 2.5), respectively. Higher relative humidity at mean day air temperature <22.1 degrees C was associated with adjusted NIBUT and SBUT, with B (95% CI) 0.16 (0.03-0.29) and 0.37 (-0.01 to 0.75), respectively. Air velocity below recommended winter values and reduced relative humidity in the range of 15-30% were associated with dry air and too low temperature. PRACTICAL IMPLICATIONS: Thermal climate in university buildings may be associated with both perceptions and physiological signs. Reduced night time air temperature, increased difference in air temperature between day and night, and fast changes in air temperature might impair indoor environment. This may have implication for energy-saving policies. It might be difficult to identify the exposure behind, and find the reason why, some buildings are defined as 'problem buildings'.