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

Indoor Airborne Microbiome and Endotoxin: Meteorological Events and Occupant Characteristics Are Important Determinants

Airborne bacteria and endotoxin may affect asthma and allergies. However, there is limited understanding of the environmental determinants that influence them. This study investigated the airborne microbiomes in the homes of 1038 participants from five cities in Northern Europe: Aarhus, Bergen, Reykjavik, Tartu, and Uppsala. Airborne dust particles were sampled with electrostatic dust fall collectors (EDCs) from the participants' bedrooms. The dust washed from the EDCs' clothes was used to extract DNA and endotoxin. The DNA extracts were used for quantitative polymerase chain (qPCR) measurement and 16S rRNA gene sequencing, while endotoxin was measured using the kinetic chromogenic limulus amoebocyte lysate (LAL) assay. The results showed that households in Tartu and Aarhus had a higher bacterial load and diversity than those in Bergen and Reykjavik, possibly due to elevated concentrations of outdoor bacterial taxa associated with low precipitation and high wind speeds. Bergen-Tartu had the highest difference (ANOSIM R = 0.203) in β diversity. Multivariate regression models showed that α diversity indices and bacterial and endotoxin loads were positively associated with the occupants' age, number of occupants, cleaning frequency, presence of dogs, and age of the house. Further studies are needed to understand how meteorological factors influence the indoor bacterial community in light of climate change.

Volatile organic compounds (VOC) in homes associated with asthma and lung function among adults in Northern Europe

Associations between measured specific VOC reported to be associated with dampness and microbial growth in dwellings and asthma, lung function were investigated in 159 adults (one adult/home) from three North European cities (Reykjavik, Uppsala and Tartu). Spirometry was performed and forced vital capacity (FVC), forced expiratory volume in 1 s (FEV₁) and FEV₁/FVC were measured. Among 159 participants, 58% were females, 24.5% atopics, 25.8% current smokers and 41% reported dampness or mold at home. Dimethyl disulphide (p = 0.004), ethyl isobutyrate (p = 0.021) and ethyl 2-methylbutyrate (p = 0.035) were associated with asthma. Isobutanol (p = 0.043), 3-methyl-1-butanol (p = 0.020), 2-hexanone (p = 0.033), 1-octen-3-ol (p = 0.027), 2-methyl-1-butanol (p = 0.022) and 2-ethyl-1-hexanol (p = 0.045) were associated with lower FEV₁. Isobutanol (p = 0.004), 3-methyl-1-butanol (p = 0.001), 2-heptanone (p = 0.047) and 2-methyl-1-butanol (p = 0.002) were associated with lower FEV₁/FVC. The association between dimethyl disulphide and asthma was more pronounced in females (p for interaction 0.099). The association between 1-butanol and lower FEV₁ was more pronounced in males (p for interaction 0.046). The associations between 3-octanone (p for interaction 0.064), 2-ethyl-1-hexanol (p for interaction 0.049) and lower FEV₁, and between 2-heptanone (p for interaction 0.021), 3-octanone (p for interaction 0.008) and lower FEV₁/FVC were stronger in homes with dampness/mold. Factor analysis identified one VOC factor related to asthma and two VOC factors related to lower lung function. Increased air concentrations of 2-heptanone, ethyl 2-methylbutyrate and ethyl isobutyrate were related to prescence of certain mold species (Aspergillus sp., Cladosporum sp. and Penicillium sp.) or building dampness. Some VOC were associated with type of dwelling, building age and pet keeping. In conclusion, some VOC reported to be associated with dampness and microbial growth can be associated with asthma and lower lung function in adults. Associations between these VOC and respiratory illness can be stronger in homes with dampness/mold. There can be gender differences in respiratory health effects when exposed to indoor VOC.

Moisture damage and fungal contamination in buildings are a massive health threat - a surgeon's perspective

OBJECTIVES

Indoor air toxicity is of major public health concern due to the increase in humidity-induced indoor mould exposure and associated health changes. The objective is to present evidence for the causality of health threats and indoor mould exposure.

METHODS

PubMed search on the following keywords: dampness, mould, indoor air quality, public health, dampness, and mould hypersensitivity syndrome, sick building syndrome, and building-related illness as well as information from the health authorities of Bavaria and North Rhine-Westphalia, the Center of Disease Control (CDC), World Health Organisation (WHO), and guidelines of professional societies.

RESULTS

The guidelines of professional societies published in 2017 are decisive for the assessment of the impact of mould pollution caused by moisture damage on human health and for official regulations in Germany. Until 2017, a causal connection between moisture damage and mould exposure could usually only be established for pulmonary diseases. The health risk of fungal components is apparent as documented in the fungal priority pathogens list (FPPL) of the WHO. Since 2017, studies, especially in Scandinavia, have proved causality between moisture and mould exposure not only for pulmonary diseases but also for extrapulmonary diseases and symptoms. This was made possible by new test methods for determining the toxicity of fungal components in indoor air. Environmental medical syndromes, e.g., dampness and mould hypersensitivity syndrome (DMHS), sick building syndrome (SBS), building-related symptoms (BRS), and building-related illness (BRI), and fungal pathogens, e.g., Aspergillus fumigatus, pose a major threat to public health.

CONCLUSION

There is evidence for the causality of moisture-induced indoor moulds and severe health threats in these buildings. According to these findings, it is no longer justifiable to ignore or trivialize the mould contamination induced by moisture damage and its effects on pulmonary and extrapulmonary diseases. The health and economic implications of these attitudes are clear.

Structural Home Defects Are the Leading Cause of Mold in Buildings: The Housing and Health Service Experience

The study aimed to evaluate the contribution of building problems to mold proliferation in dwellings. We investigated 503 dwellings of patients suffering from respiratory diseases, whose attending physicians had requested a home inspection if the area of mold was equal to at least one square meter. After careful visual evaluation and basic environmental measurements performed by a trained technician, environmental issues were classified into building defects, accidental water damage, and condensation. Data analysis demonstrated that building defects were the pre-eminent cause of mold proliferation. Among the building defects, water infiltration through leaks in roofs or walls was the leading cause. These results highlight the need for health professionals managing patients with respiratory diseases to be able to request a home inspection, and for city health authorities to commission professionals who can focus on building problems and find ways to address them.

Season, Vegetation Proximity and Building Age Shape the Indoor Fungal Communities’ Composition at City-Scale

Exposure to particular microbiome compositions in the built environment can affect human health and well-being. Identifying the drivers of these indoor microbial assemblages is key to controlling the microbiota of the built environment. In the present study, we used culture and metabarcoding of the fungal Internal Transcribed Spacer ribosomal RNA region to assess whether small-scale variation in the built environment influences the diversity, composition and structure of indoor air fungal communities between a heating and an unheated season. Passive dust collectors were used to collect airborne fungi from 259 dwellings representative of three major building periods and five building environments in one city—Lausanne (Vaud, Switzerland)—over a heating and an unheated period. A homogenous population (one or two people with an average age of 75 years) inhabited the households. Geographic information systems were used to assess detailed site characteristics (altitude, proximity to forest, fields and parks, proximity to the lake, and density of buildings and roads) for each building. Our analysis indicated that season was the factor that explained most of the variation in colonies forming unit (CFU) concentration and indoor mycobiome composition, followed by the period of building construction. Fungal assemblages were more diverse during the heating season than during the unheated season. Buildings with effective insulation had distinct mycobiome compositions from those built before 1975 — regardless of whether they were constructed with pre-1945 technology and materials or 1945 — 1974 ones. The urban landscape—as a whole—was a significant predictor of cultivable Penicillium load—the closer the building was to the lake, the higher the Penicillium load—but not of fungal community composition. Nevertheless, the relative abundance of eleven fungal taxa detected by metabarcoding decreased significantly with the urbanization gradient. When urban landscape descriptors were analyzed separately, the explanatory power of proximity to vegetation in shaping fungal assemblages become significant, indicating that land cover type had an influence on fungal community structure that was obscured by the effects of building age and sampling season. In conclusion, indoor mycobiomes are strongly modulated by season, and their assemblages are shaped by the effectiveness of building insulation, but are weakly influenced by the urban landscape.

Characteristics of annual mold variations and association with childhood allergic symptoms/diseases via combining surveys and home visit measurements

The presence of dampness and visible molds leads to concerns of poor indoor air quality which has been consistently linked with increased exacerbation and development of allergy and respiratory diseases. Due to the limitations of epidemiological surveys, the actual fungal exposure characteristics in residences has not been sufficiently understood. This study aimed to characterize household fungal diversity and its annual temporal and spatial variations. We developed combined cross-sectional survey, repeated air sampling around a year, and DNA sequencing methods. The questionnaire survey was conducted in 2019, and 4943 valid cases were received from parents; a follow-up case-control study (11 cases and 12 controls) was designed, and onsite measurements of indoor environments were repeated in typical summer, transient season, and winter; dust from floor and beddings in children's room were collected and ITS based DNA sequencing of totally 68 samples was conducted. Results from 3361 children without changes to their residences since birth verified the significant associations of indoor dampness/mold indicators and prevalence of children-reported diseases, with increased adjusted odd ratios (aORs) >1 for studied asthma, wheeze, allergic rhinitis, and eczema. The airborne fungal concentrations from air sampling were higher than 1000 CFU/m³ in summer, regardless of indoors and outdoors, indicating an intermediate pollution level. The DNA sequencing for dust showed the Aspergillus was the predominant at genus level and the Aspergillus_penicillioides was the most common at species level; while the fungal community and composition varied significantly in different homes and seasons, according to α and β diversity analyses. The comprehensive research methods contribute to a holistic understanding of indoor fungal exposure, including the concentrations, seasonal variations, community, and diversity, and verifies the relations with children's adverse health outcomes. The study further elucidates the role of microbiome in human health, which helps setting health-protective thresholds and managing mold treatments in buildings, to promote indoor air quality and human well-beings.

Prevalence, Risk Factors and Impacts Related to Mould-Affected Housing: An Australian Integrative Review

In response to an Australian governmental inquiry into biotoxin-related illness, the purpose of this integrative review is to bring together the current state of evidence on the prevalence, risk factors and impacts related to mould-affected housing in an Australian context, in order to inform building, housing and health research, practice and policy. The robust integrative review methodology simultaneously sought quantitative and qualitative studies and grey literature from multiple disciplines, identifying only 45 studies directly relating to Australian housing and indoor mould. Twenty-one studies highlight negative health impacts relating to indoor residential mould, with asthma, respiratory, allergy conditions and emerging health concerns for chronic multiple-symptom presentation. The majority of studies reported risk factors for indoor mould including poor housing conditions, poor-quality rental accommodation, socioeconomic circumstance, age-related housing issues and concerns for surface/interstitial condensation and building defects in newer housing. Risks for indoor mould in both older and newer housing raise concerns for the extent of the problem of indoor mould in Australia. Understanding the national prevalence of housing risks and “root cause” associated with indoor mould is not conclusive from the limited existing evidence. Synthesis of this evidence reveals a lack of coverage on: (1) national and geographical representation, (2) climatical coverage, (3) housing typologies, (4) housing defects, (5) maintenance, (6) impact from urbanisation, and (7) occupant’s behaviour. This integrative review was key in identifying emerging housing and health concerns, highlighting gaps in data and implications to be addressed by researchers, practice and policy and acts as a comprehensive holistic review process that can be applied to other countries.

Indoor home environments of Danish children and the socioeconomic position and health of their parents: A descriptive study

BACKGROUND

Housing and indoor home environments are associated with the risk of infections and asthma in children. To better understand the determinants and characteristics of these environments, we aimed to describe the associations between parental health and socioeconomic position and housing and indoor home environments of children in Denmark, and the clustering of the factors within these environments.

METHODS

Offspring in the Danish National Birth Cohort (DNBC) whose parents responded to the 11-year follow-up were eligible for inclusion. We included complete cases only. Data on the indoor and housing environments (i.e. variables on housing, sources of gaseous and particle pollution, mould and moisture, and pets) were collected through an online questionnaire responded to by a parent. Data on socioeconomic position were obtained through linkage with registry data on maternal education at offspring birth and household equivalized income at offspring birth. Data on parental health were obtained by linking self-reported data from the 11-year follow-up for mother and father with administrative registry data for the mother. We present descriptive statistics and exploratory factor analyses.

RESULTS

A total of 42 723 offspring were included for analyses. The distributions of nearly all indoor and housing environments differed according to educational and income strata, with patterns similar for both education and income. Generally, higher parental educational and income strata had more favorable indoor and housing environments (less secondhand smoking, gas stove use, mould and condensation and higher house ownership, detached house dwellings and newer building age). However, candle use was approximately similar between strata, fireplace use among lower educational and income strata tended towards the extremes (none or daily), and water damage was more common among higher educational and income strata. Parental health was strongly associated with housing and indoor home environment factors - especially parental affective disorders was strongly associated with mould. Four factors were extracted from the exploratory factor analyses, relating primarily in order of extraction to: housing ownership, mould and moisture, candle use and household density.

CONCLUSION

Parental health and socioeconomic position are strongly related to housing and indoor home environments. Additionally, several factors in these environments correlate strongly and cluster together. Observational studies on associations and causal effects of factors in the indoor and housing environments of children on their morbidity, must consider both of these conclusions to arrive at valid estimates and effects.

Eczema, facial erythema, and seborrheic dermatitis symptoms among young adults in China in relation to ambient air pollution, climate, and home environment

A questionnaire survey on dermal symptoms and home environment was performed in eight Chinese cities (40 279 participants). Data on city level temperature, precipitation, PM₁₀ , NO_2, and gross domestic product (GDP) per capita were collected. In total, 2.2% had eczema, 2.4% facial erythema (FE) and 2.6% seborrheic dermatitis symptoms (SD). Higher temperature was associated with eczema (OR = 1.09). Higher GDP per capita was related to less SD. Higher PM₁₀ was related to SD. Suburban living was protective for eczema (OR = 0.77) (vs. urban). Living in old buildings (built before 1991) was related to eczema (OR = 1.42). Living near heavily trafficked roads was related to FE (OR = 1.33) and SD (OR = 1.35). Having new furniture was related to all symptoms (OR = 1.26-1.47). Burning mosquito coils (OR = 1.37-1.57) and incense (OR = 1.33-1.37) were associated with eczema, FE, or SD. Presence of cockroaches and rats/mice was associated with FE or SD (OR = 1.31-1.40). Using air conditioner, daily cleaning and frequently exposing bedding to sunshine were protective (OR = 0.60-0.83). In conclusion, higher temperature, higher PM₁₀ , urban living, living near heavily trafficked roads, old buildings, new furniture, burning mosquito coils and incense, and presence of cockroaches/rats/mice increased the risk of eczema, FE, or SD. Higher GDP, air conditioner, daily cleaning, and exposing bedding to sunshine were protective.

The home environment in a nationwide sample of multi-family buildings in Sweden: associations with ocular, nasal, throat and dermal symptoms, headache, and fatigue among adults

Risk factors at home for ocular, nasal, throat and dermal symptoms, headache, and fatigue were studied in a nationwide questionnaire survey in Sweden, the BETSI study in 2006. Totally, 5775 adults from a stratified random sample of multi-family buildings participated. Associations between home environment factors and weekly symptoms were analyzed by multi-level logistic regression. In total, 8.3% had ocular symptoms; 11.9% nasal symptoms; 7.1% throat symptoms; 11.9% dermal symptoms; 8.5% headache and 23.1% fatigue. Subjects in colder climate zones had more mucosal and throat symptoms but less fatigue and ocular symptoms. Rented apartments had poorer indoor environment than self-owned apartments. Those living in buildings constructed from 1961 to 1985 had most symptoms. Building dampness, mold and mold odor were risk factors, especially headache and ocular symptoms. Lack of mechanical ventilation system was another risk factor, especially for headache. Environmental tobacco smoke (ETS), electric radiators, and crowdedness were other risk factors. Oiled wooden floors, recent indoor painting, and new floor materials were negatively associated with symptoms. In conclusion, building dampness, mold, poor ventilation conditions, crowdedness, ETS, and emissions from electric radiators in apartments in Sweden can increase the risk of ocular, nasal, throat and dermal symptoms, headache, and fatigue.

Evaluating the effect of building construction periods on household dampness/mold and childhood diseases corresponding to different energy efficiency design requirements

Despite concerns about building dampness and children' health, few studies have examined the effects of building energy efficiency standards. This study explored the connections between self-reported household dampness and children' adverse health outcomes across buildings corresponding to construction periods (pre-2001, 2001-2010, post-2010). Significant differences of dampness-related indicators were found between buildings; the prevalence was remarkable in pre-2001 buildings. The prevalence of lifetime-ever doctor-diagnosed diseases for children was significantly associated with building dampness (adjust odd ratios > 1), but was not affected by construction periods. The hygrothermal performance for a typical residence was simulated, varying in U-values of envelopes and air change rates. The simulated performance improvement increased indoor temperatures in 2001-2010 and post-2010 buildings. The frequency with higher indoor relative humidity was higher in pre-2001 buildings, leading to the highest values for maximum mold index (M_max ) on wall surface, especially in winter. Compared to buildings in 2001-2010, increased insulation and lower air change rate led to a relatively higher relative humidity in post-2010 buildings, adversely increasing the M_max values. The findings addressed the positive and negative role of building standard development, which help suggesting appropriate environmental and design solutions to trade-off energy savings and dampness/mold risk in residences.

A prospective study on the role of smoking, environmental tobacco smoke, indoor painting and living in old or new buildings on asthma, rhinitis and respiratory symptoms

We studied associations between tobacco smoke, home environment and respiratory health in a 10 year follow up of a cohort of 11,506 adults in Northern Europe. Multilevel logistic regression models were applied to estimate onset and remission of symptoms. Current smokers at baseline developed more respiratory symptoms (OR = 1.39-4.43) and rhinitis symptoms (OR = 1.35). Starting smoking during follow up increased the risk of new respiratory symptoms (OR = 1.54-1.97) and quitting smoking decreased the risk (OR = 0.34-0.60). ETS at baseline increased the risk of wheeze (OR = 1.26). Combined ETS at baseline or follow up increased the risk of wheeze (OR = 1.27) and nocturnal cough (OR = 1.22). Wood painting at baseline reduced remission of asthma (OR 95%CI: 0.61, 0.38-0.99). Floor painting at home increased productive cough (OR 95%CI: 1.64, 1.15-2.34) and decreased remission of wheeze (OR 95%CI: 0.63, 0.40-0.996). Indoor painting (OR 95%CI: 1.43, 1.16-1.75) and floor painting (OR 95%CI: 1.77, 1.11-2.82) increased remission of allergic rhinitis. Living in the oldest buildings (constructed before 1960) was associated with higher onset of nocturnal cough and doctor diagnosed asthma. Living in the newest buildings (constructed 1986-2001) was associated with higher onset of nocturnal breathlessness (OR = 1.39) and rhinitis (OR = 1.34). In conclusion, smoking, ETS and painting indoor can be risk factors for respiratory symptoms. Wood painting and floor painting can reduce remission of respiratory symptoms. Smoking can increase rhinitis. Living in older buildings can be a risk factor for nocturnal cough and doctor diagnosed asthma. Living in new buildings can increase nocturnal dyspnoea and rhinitis.

House characteristics and condition as determinants of visible mold and musty odor: Results from three New Zealand House Condition Surveys in 2005, 2010, and 2015

This study assessed associations between house characteristics and mold and musty odor, using data from three consecutive (2005, 2010, and 2015) New Zealand House Condition Surveys, involving a total of 1616 timber-framed houses. Mold, musty odor, and house characteristics were assessed by independent building inspectors. We used multivariate logistic regression analyses mutually adjusted for other house characteristics for each survey separately. Positive and independent associations were found with tenure, ventilation, insulation, and envelope condition for both mold in living and bedrooms and musty odor. In particular, we found significant dose-response associations with envelope condition, ventilation, and insulation. Odds of mold increased 2.4-15.9 times (across surveys) in houses with the worst building envelope condition (BEC; p < 0.05-0.001 for trend); optimal ventilation reduced the risk of mold by 60% and the risk of musty odor by 70%-90% (p < 0.01 for trend). Other factors associated with mold and musty odor included: tenure, with an approximate doubling of odds of mold across surveys; and insulation with consistent dose-response patterns in all outcomes and surveys tested (p < 0.05 for trend in two surveys with mold and one survey for odor). In conclusion, this study showed the importance of BEC, ventilation, and insulation to avoiding harmful damp-related exposures.

Fungal Contaminants in Energy Efficient Dwellings: Impact of Ventilation Type and Level of Urbanization

The presence of growing fungi in the indoor environment has been associated with the development of respiratory problems such as asthma or allergic rhinitis, as well as the worsening of respiratory pathologies. Their proliferation indoors could be a result of water leakage or inadequate ventilation. Although the factors promoting mould growth have been widely investigated in traditional dwellings, little work has been done in energy efficient dwellings. Here, the effectiveness of ventilation type, i.e., natural or mechanical, in influencing mould development was estimated in 44 recent and 105 retrofitted energy efficient dwellings. Fungi growing on surfaces were investigated in the dwellings situated in rural, peri-urban, and urban regions of Switzerland. The presence of these fungi was also investigated in bedroom settled dust. Information on building characteristics and owners' lifestyle were collected. Significant associations were found with the level of urbanisation, the location of mouldy area in dwellings, and the diversity of fungal taxa. Dwellings in peri-urban zones showed the most frequent fungal contamination in the owners' bedroom and the highest diversity of fungal genera among dwellings. While the urbanisation level or the ventilation type favoured no specific genus, we found marked disparities in the diversity of fungi growing on surfaces in naturally ventilated versus mechanically ventilated dwellings. Aspergillus, in particular, was a frequent surface contaminant in bedrooms with natural ventilation, but not in those mechanically ventilated. We observed a strong association between fungal growth on surfaces and the number of fungal particles counted in the settled dust of owners' bedrooms. These results demonstrate the importance of ventilation systems in energy efficient dwellings in controlling fungal proliferation in living areas.

Associations of household dampness with asthma, allergies, and airway diseases among preschoolers in two cross-sectional studies in Chongqing, China: Repeated surveys in 2010 and 2019

Many studies have investigated the associations between household damp indicators, and allergies and respiratory diseases in childhood. However, the findings are rather inconsistent. In 2010, we conducted a cross-sectional study of preschoolers aged three-six years in three urban districts of Chongqing, China. In 2019, we repeated this cross-sectional study with preschoolers of the same ages and districts. Here, we selected data for 2935 and 2717 preschoolers who did not change residences since birth in the 2010 and 2019 studies, respectively. We investigated associations of household damp indicators with asthma, allergic rhinitis, pneumonia, eczema, wheeze, and rhinitis in childhood in the two studies. The proportions of residences with household damp indicators and the prevalence of the studied diseases (except for allergic rhinitis) were significantly lower in 2019 than in 2010. In the two-level (district-child) logistic regression analyses, household damp exposures that showed by different indicators were significantly associated with the increased odds of lifetime-ever asthma (range of adjusted odds ratio (AOR): 1.69-3.50 in 2019; 1.13-1.90 in 2010), allergic rhinitis (1.14-2.39; 0.67-1.61), pneumonia (1.09-1.64; 1.21-1.59), eczema (0.96-1.83; 0.99-1.56), wheeze (1.64-2.79; 1.18-1.91), rhinitis (1.43-2.71; 1.08-1.58), and current (in the past 12 months before the survey) eczema (0.46-2.08; 0.99-1.48), wheeze (0.97-2.86; 1.26-2.07) and rhinitis (1.34-2.25; 1.09-1.56) in most cases. The increased odds ratios (ORs) of most diseases had exposure-response relationships with the cumulative number (n) of household damp indicators in the current and early residences. Our results indicated household damp exposure could be a risk factor for childhood allergic and respiratory diseases, although the magnitudes of these effects could be different in different studies.

Dampness and mold at home and at work and onset of insomnia symptoms, snoring and excessive daytime sleepiness

AIM

To investigate whether exposure to dampness and mold at home and at work induce sleep disturbances and daytime sleepiness among adults.

MATERIALS AND METHODS

Associations between onset of sleep disturbances and dampness, mold and mold odor at home and at work were investigated in a cohort of 11,318 adults from the population in Iceland, Norway, Sweden, Denmark and Estonia. The participants answered a questionnaire at baseline and 10 years later, with questions on sleep disturbances, including difficulty initiating sleep (DIS), difficulty maintaining sleep (DMS), early morning awakening (EMA), insomnia symptoms, snoring and excessive daytime sleepiness (EDS). Multiple logistic regression models were applied to estimate associations adjusting for potential confounders including gender, age, smoking habit at baseline, change of smoking habit from baseline to follow up, BMI at baseline, change of BMI from baseline to follow up, education level at follow up, allergic rhinitis at baseline, doctor diagnosed asthma at baseline and chronic bronchitis at baseline.

RESULTS

Baseline floor dampness, visible mold and mold odor at home increased onset of DIS, DMS, EMA, insomnia symptoms and snoring during follow up (OR 1.29-1.87). Any sign of dampness at baseline increased onset of DIS (OR 1.28, 95%CI 1.06-1.55), DMS (OR 1.17, 95%CI 1.02-1.34) and insomnia symptoms (OR 1.18, 95%CI 1.03-1.36). Dampness at home during follow up increased onset of DIS, DMS, EMA, insomnia symptoms and EDS (OR 1.17-1.36). Dampness at work during follow up increased onset of DIS, EMA, insomnia symptoms and EDS (OR 1.16-1.34). Combined dampness at home and at work during follow up increased the risk of onset of DIS, DMS, EMA, insomnia symptoms and EDS (OR 1.29-1.74).

CONCLUSIONS

Dampness and mold at home and at work can increase the development of insomnia symptoms, snoring and EDS among adults.

High prevalence of eczema among preschool children related to home renovation in China: A multi-city-based cross-sectional study

We surveyed 40 010 three- to six-year-old children in seven Chinese cities (Beijing, Taiyuan, Urumqi, Shanghai, Nanjing, Changsha, and Chongqing) during 2010-2012 so as to investigate possible links between home renovation and childhood eczema. Their parents responded to questions on home renovation and childhood eczema. Multivariate and two-level (city-child) logistic regression analyses yielding odds ratios with 95% confidence intervals were performed. Sensitivity analyses stratifying data for region, climate, and income level were also performed. The prevalences of childhood eczema in children with different floor and wall covering materials were significantly different and were significantly higher with home renovation during early lifetime. Exposure to synthetic materials significantly increased the risk of childhood eczema by 20%-25%. The risks (AOR, 95% CI) of current eczema among children in families with solid wood flooring and oil paint wall covering were 1.25 (1.04-1.49) and 1.35 (1.14-1.60), respectively. Home renovation during pregnancy was related to children's lifetime and current eczema.

Asthma, allergic rhinitis and eczema among parents of preschool children in relation to climate, and dampness and mold in dwellings in China

The main aim was to study associations between asthma, allergic rhinitis and eczema among adults across China and dampness and mold at home. Young adults (N = 40,279) in eight cities in China answered a questionnaire in 2010-2012 (response rate 75.0%). Data on asthma, allergic rhinitis, eczema and the home environment was assessed by the questionnaire. Climate data was obtained from China Meteorological Administration and the website of Weather Underground. Health associations were analyzed by two-level logistic regression models, adjusting for covariates. Totally 1.6% had asthma, 6.6% allergic rhinitis and 2.2% eczema. Mold odor was associated with asthma (OR = 1.90) and allergic rhinitis (OR = 1.25-1.44). Window pane condensation in winter was associated with asthma (OR = 1.39), allergic rhinitis (OR = 1.26-1.58) and eczema (OR = 1.36-1.77). Presence of mold spots or damp stains was related to asthma (OR = 1.58-2.49), allergic rhinitis (OR = 1.35-1.76) and eczema (OR = 1.47-1.70). Water damage was related to asthma (OR = 1.69-1.82), allergic rhinitis (OR = 1.40-1.45) and eczema (OR = 1.44-1.96). Damp bed clothing was related to asthma (OR = 1.23), allergic rhinitis (OR = 1.23) and eczema (OR = 1.35). A higher dampness score was associated with increased odds ratios for diseases. Those living in older buildings had more asthma (OR = 1.39-1.76) and allergic rhinitis (OR = 1.16-1.21). Those living in suburban or rural areas had less asthma, allergic rhinitis and eczema as compared to those living in urban areas (OR values from 0.24 to 0.66). Stronger health associations with dampness and mold were found in southern China and in newer buildings (constructed after 2005). In conclusion, dampness and mold at home can be risk factors for asthma, allergic rhinitis and eczema among adults in China. Living in older buildings can be risk factors for asthma or allergic rhinitis while living in less urbanized areas can be protective.

[Meteorological variables and air pollution and their association with hospitalizations due to respiratory diseases in children: a case study in São Paulo, Brazil]

Urban climate changes, excessive air pollution, and increasing social inequalities have become determinant factors in the high risk of hospitalizations due to respiratory diseases. The current study thus aimed to understand how meteorological factors (air temperature, relative humidity, and precipitation) and air pollution (particulate matter with aerodynamic diameter less than 10µm - PM10) are related to hospitalizations due to respiratory diseases in children in 14 districts in the city of São Paulo, Brazil. The combination of generalized linear models with a negative binomial distribution and distributed lag non-linear model (DLNM) were used as the statistical method to analyze the relationship between hospitalizations, climatic factors, and pollution from 2003 to 2013. The results show statistically significant association with high relative risk between mean air temperature (17.5ºC to 21ºC, for the total analyzed), relative humidity (84% to 98% for females), precipitation (0mm to 2.3mm for the total and both sexes and > 120mm for females), and PM10 (> 35µg/m³ for the total and for females). These results showed that environmental factors contribute to the high risk of hospitalizations.

Dampness, mould, onset and remission of adult respiratory symptoms, asthma and rhinitis

STUDY QUESTION

Is dampness and indoor mould associated with onset and remission of respiratory symptoms, asthma and rhinitis among adults?

MATERIALS AND METHODS

Associations between dampness, mould and mould odour at home and at work and respiratory health were investigated in a cohort of 11 506 adults from Iceland, Norway, Sweden, Denmark and Estonia. They answered a questionnaire at baseline and 10 years later, with questions on respiratory health, home and work environment.

RESULTS

Baseline water damage, floor dampness, mould and mould odour at home were associated with onset of respiratory symptoms and asthma (OR 1.23-2.24). Dampness at home during follow-up was associated with onset of respiratory symptoms, asthma and rhinitis (OR 1.21-1.52). Dampness at work during follow-up was associated with onset of respiratory symptoms, asthma and rhinitis (OR 1.31-1.50). Combined dampness at home and at work increased the risk of onset of respiratory symptoms and rhinitis. Dampness and mould at home and at work decreased remission of respiratory symptoms and rhinitis.

THE ANSWER TO THE QUESTION

Dampness and mould at home and at work can increase onset of respiratory symptoms, asthma and rhinitis, and decrease remission.

Sources of indoor particulate matter (PM) and outdoor air pollution in China in relation to asthma, wheeze, rhinitis and eczema among pre-school children: Synergistic effects between antibiotics use and PM10 and second hand smoke

We studied indoor sources of indoor particulate matter (PM), outdoor air pollution and antibiotic use in relation to asthma, rhinitis and eczema among pre-school children and investigated synergistic effects between PM and antibiotics use. Children (3-6y) from randomly selected day care centres in seven cities across China were included (n = 39,782). Data on ambient temperature and air pollution were collected from local monitoring stations. Data on indoor PM sources (ETS, burning of incense or mosquito coils and biomass for cooking), antibiotics use and health (doctor diagnosed asthma and rhinitis, lifetime eczema, current wheeze and current rhinitis) were assessed by a parental questionnaire. Associations were calculated by multilevel logistic regression. Asthma diagnosis was associated with outdoor temperature, NO₂ and burning mosquito coils. Rhinitis diagnosis was associated with NO₂, ETS, gas cooking and burning biomass for cooking. Lifetime eczema was associated with temperature, PM_10, NO₂, ETS, biomass cooking and burning mosquito coils. Burning incense was associated with current wheeze and current rhinitis. Children using antibiotics had more asthma, wheeze, rhinitis, and eczema. Excluding children with respiratory infections did not change associations with antibiotics use. Antibiotics use enhanced the effects of ETS and PM₁₀ (a synergistic effect). In conclusion, a warmer climate, outdoor NO₂ and PM_10, ETS, gas cooking and burning biomass, incense and mosquito coils can increase the risk of asthma, wheeze, rhinitis and eczema among pre-school children in China. Antibiotics use is a risk factor for childhood asthma, wheeze, rhinitis and eczema and ETS and outdoor PM₁₀ can enhance the effect.

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.

Asthma and rhinitis among Chinese children - Indoor and outdoor air pollution and indicators of socioeconomic status (SES)

BACKGROUND

Few data exist on asthma and rhinitis across China in relation to indoor and outdoor air pollution, climate and socioeconomic factors. The main aim was to study associations between asthma, rhinitis and current respiratory symptoms among pre-school children across China and selected indoor and outdoor exposure and indicators of socio-economic status (SES) in mutually adjusted models.

METHODS

Chinese children (3-6 yr.) (n = 39,782) were recruited from randomly selected day care centres in seven cities in China. Data on asthma, respiratory symptoms, rhinitis, indoor and outdoor exposure at home and SES were assessed by a parentally administered questionnaire. Lifetime mean ambient temperature, PM₁₀, NO_2, and GDP per capita on city level were calculated.

RESULTS

Totally 7.4% had ever doctors' diagnosed (DD) asthma and 8.7% DD-rhinitis, 19.7% had current wheeze, 45.0% rhinitis and 16.9% cough. DD-asthma was associated with ambient temperature (OR = 1.15, 95% CI 1.11-1.20 per °C), NO₂ (OR = 1.16, 95% CI 1.02-1.33 per 10 μg/m³), indoor mould/dampness (OR = 1.25, 95% CI 1.13-1.39) and living near major roads (OR = 1.13, 95% CI 1.02-1.25). DD-rhinitis was associated with ambient temperature (OR = 1.07, 95% CI 1.05-1.10 per °C), NO₂ (OR = 1.20, 95% CI 1.09-1.32 per 10 μg/m³), GDP (OR = 1.03, 95% CI 1.01-1.06 per 10,000 RenMinBi/year), indoor mould/dampness (OR = 1.23, 95% CI 1.11-1.35), passive smoking (OR = 1.11, 95% CI 1.01-1.21), and living near major roads (OR = 1.14, 95% CI 1.03-1.25). Children in suburban or rural areas, in larger families (≥5 persons) and with prenatal farm exposure had less DD-asthma and DD-rhinitis.

CONCLUSIONS

Economic development level of the city, higher SES, ambient temperature, NO₂, PM₁₀, traffic air pollution and mould/dampness can be risk factors for asthma and rhinitis and respiratory symptoms among pre-school children in China. Breastfeeding, large family size and early-life farm exposure could be protective factors.

Association between Four-Level Categorisation of Indoor Exposure and Perceived Indoor Air Quality

The aim of this study was to develop and test a tool for assessing urgency of indoor air quality (IAQ) measures. The condition of the 27 buildings were investigated and results were categorized. Statistical test studied the differences between the categories and the employees&rsquo; complaints about their work environment. To study the employees&rsquo; experiences of the work premises, a validated indoor air (IA) questionnaire was used. This study reveals a multifaceted problem: many factors affecting IAQ may also affect perceived IAQ, making it difficult to separate the impurity sources and ventilation system deficiencies affecting to employee experiences. An examination of the relationship between the categories and perceived IAQ revealed an association between the mould odour perceived by employees and mould detected by the researcher. A weak link was also found between the assessed categories and environmental complaints. However, we cannot make far-reaching conclusions regarding the assessed probability of abnormal IA exposure in the building on the basis of employee experiences. According to the results, categorising tool can partly support the assessment of the urgency for repairs when several factors that affect IAQ are taken into account.

Common cold among pre-school children in China - associations with ambient PM10 and dampness, mould, cats, dogs, rats and cockroaches in the home environment

BACKGROUND

There is some evidence that dampness, mould and cockroaches can increase the risk of respiratory infections in children but few studies exist from China on this topic. Aim To study associations between domestic early life exposure to biological indoor factors (dampness, mould, cats, dogs, rats, cockroaches), cleaning habits and common cold among pre-school children across China.

METHODS

Children aged 3-6years (n=39,782) were recruited from randomly selected day care centres in seven cities in China. Data on common cold and prenatal and postnatal exposure to dampness, mould, windowpane condensation in wintertime (WPC), cats, dogs, cockroaches and rats were assessed by a parentally administered questionnaire. Data on annual ambient temperature and PM₁₀ was assessed on city level. Associations between high frequency (>5 colds per year) and long duration (≥2weeks) of common colds in the past year and exposure were calculated by multilevel logistic regression.

RESULTS

A total of 9.2% had a high frequency and 11.9% had long duration of common cold. Exposure to mould (OR=1.38, 95% CI 1.24-1.53) and WPC (OR 1.23, 95%CI 1.13-1.33) at birth was associated with frequent common cold. Exposure to dogs at birth was associated with long duration of common cold. (OR=1.22, 95% CI 1.06-1.41). Exposure to mould (OR=1.36, 95% CI 1.22-1.54), WPC (OR=1.27, 95%CI 1.17-1.39) and water leakage (OR 1.34, 95% CI 1.20-1.49) in the current home was associated with frequent common cold. Presence of cockroaches were positively (OR=1.12, 95% CI 1.02-1.24) and presence of rats (OR=0.86, 95% CI 0.77-0.96) negatively associated with high frequency of common cold. Daily cleaning was negatively associated with frequent common cold (OR=0.89, 95% CI 0.81-0.97). Similar associations for mould, WPC, cockroaches and rats were found for long duration. Ambient PM₁₀ (OR=1.21, 95% CI 1.21-1.35 per 10μg/m³) and temperature (OR=1.13, 95% CI 1.06-1.35 °C) on city level were associated with high frequency of common cold. Associations between cat keeping and high frequency of common cold were found only in southern China. Associations with cockroaches were stronger in northern China. Associations with dampness and mould were the same in the north and south.

CONCLUSIONS

Indoor mould, water damage, windowpane condensation, cockroaches and keeping cats or dogs as pets can be risk factors for common cold while daily cleaning can be protective factor. PM₁₀ and a warmer climate zone can be other risk factors for common cold.