Advertisement

Indoor molds and lung function in healthy adults

  • Samu Hernberg
    Affiliations
    Center for Environmental and Respiratory Health Research, University of Oulu, Oulu, Finland

    Respiratory Medicine Unit, Institute of Clinical Medicine, University of Oulu, Oulu, Finland

    Respiratory Medicine Unit, Oulu University Hospital, Oulu, Finland
    Search for articles by this author
  • Penpatra Sripaiboonkij
    Affiliations
    Center for Environmental and Respiratory Health Research, University of Oulu, Oulu, Finland

    Faculty of Public Health, Thammasat University, Thailand
    Search for articles by this author
  • Reginald Quansah
    Affiliations
    Center for Environmental and Respiratory Health Research, University of Oulu, Oulu, Finland
    Search for articles by this author
  • Jouni J.K. Jaakkola
    Correspondence
    Corresponding author. Center for Environmental and Respiratory Health Research, University of Oulu, P.O. Box 5000, 90014 Oulu, Finland. Tel.: +358 40 672 0927; fax: +358 8 5375661.
    Affiliations
    Center for Environmental and Respiratory Health Research, University of Oulu, Oulu, Finland

    Respiratory Medicine Unit, Oulu University Hospital, Oulu, Finland

    Public Health, Institute of Health Sciences, University of Oulu, Oulu, Finland
    Search for articles by this author
  • Maritta S. Jaakkola
    Affiliations
    Center for Environmental and Respiratory Health Research, University of Oulu, Oulu, Finland

    Respiratory Medicine Unit, Institute of Clinical Medicine, University of Oulu, Oulu, Finland

    Respiratory Medicine Unit, Oulu University Hospital, Oulu, Finland
    Search for articles by this author
Open ArchivePublished:March 20, 2014DOI:https://doi.org/10.1016/j.rmed.2014.03.004

      Summary

      Background

      Indoor mold exposure is common worldwide and constitutes an important health problem. There are very few studies assessing the relation between mold exposure and lung function levels among non-asthmatic adults. Our objective was to assess the relations between dampness and mold exposures at home and at work and lung function. In particular, we elaborated the importance of different exposure indicators.

      Methods

      In a population-based study, 269 non-asthmatic adults from South Finland answered a questionnaire on indoor dampness and mold exposures at home or at work and other factors potentially influencing lung function, and performed spirometry. Multiple linear regression model was applied to study the relations between exposures and spirometric lung function levels.

      Results

      In linear regression adjusting for confounding, FEV1 level was reduced on average 200 ml related to mold odor at home (effect estimate −0.20, 95% CI −0.60 to 0.21) and FVC level was reduced on average 460 ml (−0.46, −0.95 to 0.03) respectively. Exposure to mold odor at home or at work or both was related to reduced FEV1 (−0.15, −0.42 to 0.12) and FVC (−0.22, −0.55 to 0.11) levels. Women had on average 510 ml reduced FEV1 levels (−0.51, −1.0 to 0.03) and 820 ml reduced FVC levels (−0.82, −1.4 to −0.20) related to mold odor exposure at home.

      Conclusions

      Mold odor exposure was related to lower lung function levels among non-asthmatic adults, especially among women.

      Keywords

      Introduction

      Indoor dampness and molds are common worldwide [
      • World Health Organization (WHO) Europe
      Guidelines for indoor air quality: dampness and mold.
      ]. At least 20% of buildings in North America and Europe have one or more signs of dampness [
      • Institute of Medicine
      Damp indoor spaces and health.
      ]. In cold climate the prevalence of water damage and dampness problems is estimated at 5%–30% and in moderate and warm climates at 10%–60% [
      • Jaakkola M.S.
      • Haverinen-Shaugnessy U.
      • Douwes J.
      • Nevalainen A.
      Indoor dampness and mold problems in homes and asthma onset in children.
      ,
      • Haverinen-Shaugnessy U.
      Prevalence of dampness and mold in European housing stock.
      ]. Thus, indoor dampness-related exposures constitute an important public health problem globally.
      In a recent meta-analysis, the risk of developing asthma was significantly elevated in relation to dampness (effect estimate (EE) 1.33, 95% CI 1.12–1.56), visible mold (EE 1.29, 95% CI 1.04–1.60), and mold odor (EE 1.73, 95% CI 1.19–2.50), but not in relation to water damage (EE 1.12, 95% CI 0.98–1.27) [
      • Quansah R.
      • Jaakkola M.S.
      • Hugg T.T.
      • Heikkinen S.A.M.
      • Jaakkola J.J.K.
      Residential dampness and molds and the risk of developing asthma: a systematic review and meta-analysis.
      ]. Thus, the evidence indicated that dampness and molds in the home are determinants of asthma onset. Another meta-analyses provided evidence that dampness and mold problems increase the risk of allergic (AR) and non-allergic rhinitis: the largest risk was observed in relation to mold odor (rhinitis: 2.18 [95% CI, 1.76–2.71]; AR: 1.87 [95% CI, 0.95–3.68]). The risk related to visible mold was also consistently increased (rhinitis: 1.82 [95% CI, 1.56–2.12]; AR: 1.51 [95% CI, 1.39–1.64]; rhinoconjunctivitis: 1.66 [95% CI, 1.27–2.18]) In addition, exposure to dampness was related to increased risk of all types of rhinitis [
      • Jaakkola M.S.
      • Quansah R.
      • Hugg T.T.
      • Heikkinen S.A.M.
      • Jaakkola J.J.K.
      Association of indoor dampness and molds with rhinitis risk: a systematic review and meta-analysis.
      ].
      On the basis of the evidence on these adverse respiratory effects, lung function is a plausible target for adverse effects of dampness and mold problems. Our systematic literature search identified only four previous studies assessing the association between mold or dampness exposure and lung function levels in adults with no lung diseases [
      • Vojdani A.
      • Campbell A.W.
      • Kashanian A.
      • Vojdani E.
      Antibodies against molds and mycotoxins following exposure to toxigenic fungi in a water-damaged building.
      ,
      • Stark H.J.
      • Randell J.T.
      • Hirvonen M.-R.
      • Purokivi M.K.
      • Roponen M.H.
      • Tukiainen H.O.
      The effects of Aspergillus fumigatus challenge on exhaled and nasal NO levels.
      ,
      • Kilburn K.
      Neurobehavioral and pulmonary impairment in 105 adults with indoor exposure to molds compared to 100 exposed to chemicals.
      ,
      • Norbäck D.
      • Zock J.-P.
      • Plana E.
      • Heinrich J.
      • Svanes C.
      • Sunyer J.
      • et al.
      Lung function decline in relation to mould and dampness in the home: the longitudinal European Community Respiratory Health Survey ECRHS II.
      ]. All studies provided suggestive evidence of some reduction in lung function in individuals exposed to molds or dampness. One study presented some result separately for men and women [
      • Norbäck D.
      • Zock J.-P.
      • Plana E.
      • Heinrich J.
      • Svanes C.
      • Sunyer J.
      • et al.
      Lung function decline in relation to mould and dampness in the home: the longitudinal European Community Respiratory Health Survey ECRHS II.
      ]. Two of them focused on work exposure [
      • Vojdani A.
      • Campbell A.W.
      • Kashanian A.
      • Vojdani E.
      Antibodies against molds and mycotoxins following exposure to toxigenic fungi in a water-damaged building.
      ,
      • Stark H.J.
      • Randell J.T.
      • Hirvonen M.-R.
      • Purokivi M.K.
      • Roponen M.H.
      • Tukiainen H.O.
      The effects of Aspergillus fumigatus challenge on exhaled and nasal NO levels.
      ] and two on home exposure [
      • Kilburn K.
      Neurobehavioral and pulmonary impairment in 105 adults with indoor exposure to molds compared to 100 exposed to chemicals.
      ,
      • Norbäck D.
      • Zock J.-P.
      • Plana E.
      • Heinrich J.
      • Svanes C.
      • Sunyer J.
      • et al.
      Lung function decline in relation to mould and dampness in the home: the longitudinal European Community Respiratory Health Survey ECRHS II.
      ]. Our knowledge of the effect of mold and/or dampness on lung function among non-asthmatic adults is therefore limited.
      Our objective was to assess the relations between dampness and mold exposures at home and at work and lung function among working aged adults without current or previous asthma. In particular, we elaborated the importance of different exposure indicators that have been found relevant in the studies on asthma and allergic rhinitis.

      Methods

      Study population

      We conducted a population-based cross-sectional study of working aged non-asthmatic adults in a geographically defined area in Finland. The study population served as controls in the Finnish Environment and Asthma Study (FEAS), a population-based study on incident asthma [
      • Jaakkola M.S.
      • Nordman H.
      • Piipari R.
      • Uitti J.
      • Laitinen J.
      • Karjalainen A.
      • et al.
      Indoor dampness and molds and development of adult-onset asthma: a population-based incident case–control study.
      ,
      • Jaakkola J.J.K.
      • Jaakkola N.
      • Piipari R.
      • Jaakkola M.S.
      Pets, parental atopy, and asthma in adults.
      ,
      • Jaakkola M.S.
      • Piipari R.
      • Jaakkola N.
      • Jaakkola J.J.K.
      Environmental tobacco smoke and adult onset-asthma: a population-based incident case-control study.
      ,
      • Jaakkola J.J.K.
      • Piipari R.
      • Jaakkola M.S.
      Occupation and asthma: a population-based incident case-control study.
      ,
      • Jaakkola M.S.
      • Ieromnimon A.
      • Jaakkola J.J.K.
      Are atopy and specific IgE to mites and molds important for adult asthma?.
      ,
      • Jaakkola J.J.K.
      • Ieromnimon A.
      • Jaakkola M.S.
      Interior surface materials and asthma in adults: a population-based incident case-control study.
      ,
      • Jaakkola M.S.
      • Jaakkola J.J.K.
      Office work exposures and adult-onset asthma.
      ,
      • Rantala A.
      • Jaakkola J.J.K.
      • Jaakkola M.S.
      Respiratory infections precede adult-onset asthma.
      ,
      • Lajunen T.K.
      • Jaakkola J.J.K.
      • Jaakkola M.S.
      Influence of heredity on asthma continues into adulthood.
      ].
      The study population was derived from a source population consisting of adults 21–63 years old living in the Pirkanmaa Hospital district, in South Finland identified from the national population registry, which has full coverage of the population. All together there were 1016 (response rate 67%) controls of which 299 performed spirometry. After excluding 21 people diagnosed with asthma, two who were over 64 years old, three without questionnaire data and 4 duplicates, the study population constituted 269 adults with spirometric lung functions and exposure data.

      Exposure assessment

      Exposure was assessed based on questionnaire information on indoor water damage, damp stains and other marks of structural dampness, visible mold, and mold odor, both at home and at work [
      • Jaakkola M.S.
      • Nordman H.
      • Piipari R.
      • Uitti J.
      • Laitinen J.
      • Karjalainen A.
      • et al.
      Indoor dampness and molds and development of adult-onset asthma: a population-based incident case–control study.
      ,
      • Jaakkola J.J.K.
      • Jaakkola N.
      • Ruotsalainen R.
      Home dampness and molds as determinants of respiratory symptoms and asthma in pre-school children.
      ,
      • Ruotsalainen R.
      • Jaakkola N.
      • Jaakkola J.J.K.
      Dampness and molds in day-care centers as an occupational health problem.
      ,
      • Jaakkola J.J.K.
      • Hwang B.F.
      • Jaakkola M.S.
      Home dampness and molds as determinants of allergic rhinitis in childhood: a 6-year, population-based cohort study.
      ]. For water damage, damp stains, and visible mold, we asked information about their occurrence during the past year, 1–3 years before, or >3 years ago. For mold odor, we asked about occurrence during the past 12 months and inquired if such odor appeared almost daily, 1–3 days a week, 1–3 days a month, <1 day a month, or never.

      Measurement methods

      Questionnaire

      The self-administered questionnaire has been described in detail elsewhere [
      • Jaakkola M.S.
      • Nordman H.
      • Piipari R.
      • Uitti J.
      • Laitinen J.
      • Karjalainen A.
      • et al.
      Indoor dampness and molds and development of adult-onset asthma: a population-based incident case–control study.
      ,
      • Jaakkola J.J.K.
      • Jaakkola N.
      • Piipari R.
      • Jaakkola M.S.
      Pets, parental atopy, and asthma in adults.
      ,
      • Jaakkola M.S.
      • Piipari R.
      • Jaakkola N.
      • Jaakkola J.J.K.
      Environmental tobacco smoke and adult onset-asthma: a population-based incident case-control study.
      ,
      • Jaakkola J.J.K.
      • Piipari R.
      • Jaakkola M.S.
      Occupation and asthma: a population-based incident case-control study.
      ,
      • Jaakkola M.S.
      • Ieromnimon A.
      • Jaakkola J.J.K.
      Are atopy and specific IgE to mites and molds important for adult asthma?.
      ,
      • Jaakkola J.J.K.
      • Ieromnimon A.
      • Jaakkola M.S.
      Interior surface materials and asthma in adults: a population-based incident case-control study.
      ,
      • Jaakkola M.S.
      • Jaakkola J.J.K.
      Office work exposures and adult-onset asthma.
      ,
      • Rantala A.
      • Jaakkola J.J.K.
      • Jaakkola M.S.
      Respiratory infections precede adult-onset asthma.
      ,
      • Lajunen T.K.
      • Jaakkola J.J.K.
      • Jaakkola M.S.
      Influence of heredity on asthma continues into adulthood.
      ].

      Lung function measurements

      We conducted a baseline spirometry with a pneumotachygraph spirometer connected to a computer using a disposable flow transducer (Medikro 905; Medikro Ltd., Kuopio, Finland). Measurements were conducted according to the standards of the American Thoracic Society [
      • American Thoracic Society
      Standardization of spirometry, 1994 update.
      ]. We judged the presence of obstruction using the reference values derived from the Finnish population [
      • Viljanen A.A.
      • Halttunen P.K.
      • Kreus K.-E.
      • Viljanen B.C.
      Spirometric studies in non-smoking, healthy adults.
      ].

      Statistical methods

      Our outcome of interest was spirometric lung function at baseline, i.e. FEV1 and forced vital capacity (FVC) measured before the bronchodilation test. We applied multiple linear regression to estimate the relations between the dampness and mold exposure indicators and the lung function levels. First, we adjusted for three core covariates: age, sex and height. We built the full model by adding into the model current and previous smoking, exposure to second-hand smoking, and education as an indicator of socio-economic status, in addition to the three core covariates. We have previously described the variables for smoking [
      • Piipari R.
      • Jaakkola J.J.K.
      • Jaakkola N.
      • Jaakkola M.S.
      Smoking and asthma in adults.
      ] and second-hand smoking in detail [
      • Jaakkola M.S.
      • Piipari R.
      • Jaakkola N.
      • Jaakkola J.J.K.
      Environmental tobacco smoke and adult onset-asthma: a population-based incident case-control study.
      ]. We fitted a model with four exposure indicators (i.e. water damage, dampness, visible mold, each at any time, and mold odor in the last 12 months) at home and the corresponding four exposure indicators at work, so altogether eight exposure indicators. We also fitted a model including these four exposure indicators describing exposure at home and/or at work combined. In both analyses the reference category consisted of those with no dampness or mold exposure at home or at work. We estimated the relations of interest separately for men and women. Exposure to mold odor in the past 12 months was further categorized into no mold odor exposure, low exposure (reported mold odor 1–3 times a month or less frequently), and high exposure (reported mold odor 1–3 times a week or daily). The model assessing potential exposure-response relation included indicator variables for low and high exposure. The analysis was performed with SAS statistical software package (SAS, version 9.3, SAS Institute, Cary, NC).

      Results

      Characteristics of the study population and exposures

      The characteristics of the study population of non-asthmatics are displayed according to gender in Table 1. Of the 269 adults, 122 were men (45.4%) and 147 women (54.6%). Table 2 shows dampness and mold exposures of the study population. A total of 126 subjects (46.8%) reported the presence of at least one of the exposure indicators either at work or home. The most common exposure indicator was dampness at home (24.2%, n = 65), followed by dampness at work (18.2%, n = 49) and water damage at home (16.0%, n = 43). Of these 65 (24.2%) individuals reported some exposure at work and 86 (32.0%) at home. The prevalence of exposure was similar between men and women: 8.8% (N = 13) of women and 7.3% (n = 9) of men had exposure to mold odor at home.
      Table 1Characteristics of the study population (N = 269).
      CharacteristicMen (N = 122)Women (N = 147)Total (N = 269)
      n%N%n%
      Age (years)21–2975.82114.32810.4
      30–392218.03624.35821.6
      40–493226.24732.07929.4
      50–594234.43423.17628.2
      60–641915.696.12810.4
      EducationNo vocational schooling1613.12215.03814.1
      Vocational course1411.51610.93011.1
      Vocational institution3730.33423.17126.4
      College-level education3629.54732.08330.9
      University or corresponding1915.62819.04717.5
      SmokingNo4940.19162.014052.0
      Ex4436.12819.07226.8
      Current2923.82819.05721.2
      SHS in the workplace
       Yes2318.996.13211.9
      SHS at home
       Yes54.153.4103.7
      SHS = second hand smoking.
      Table 2Distribution of exposure indicators, Finnish Environment and Asthma Study (FEAS) 1997–2000 (n = 269).
      Exposure indicatorAll (N)%Men (N = 122)%Women (N = 147)%
      Workplace
      Water damage
       No23587.410686.912987.8
       Yes, during past 12 months207.4129.985.4
       Yes, 1–3 years ago83.021.664.1
       Yes, >3 years ago62.221.642.7
       Yes, any time3412.61613.11812.2
      Dampness
       No22081.89779.512383.7
       Yes, during past 12 months3713.71713.92013.6
       Yes, 1–3 years ago41.532.510.7
       Yes, >3 years ago83.054.132.0
       Yes, any time4918.22520.52416.3
      Visible mold
       No25895.911795.914195.9
       Yes, during past 12 months83.032.553.4
       Yes, 1–3 years ago31.121.610.7
       Yes, >3 years ago000000
       Yes, any time114.154.164.1
      Mold odor (in the past 12 months)
       No24992.611493.513591.8
       Yes, almost daily114.154.164.0
       Yes, 1–3 days a week31.110.821.4
       Yes, 1–3 days a month20.70021.4
       Yes, less often41.521.621.4
       Any exposure
      Exposure to mold odor at any frequency (almost daily, 1–3 days a week, 1–3 days a month, less often).
      207.486.5128.2
      Any exposure in the workplace
      Exposure to at least one of the following: water damage, dampness, visible mold or mold odor.
      No20475.89174.611376.9
      Yes6524.23125.43423.1
      Home
      Water damage
      ‘Do not know’ was answered by 1 woman.
       No22584.010384.512283.5
       Yes, during past 12 months83.021.664.1
       Yes, 1–3 years ago114.121.696.2
       Yes, >3 years ago248.91512.396.2
       Yes, any time4316.01915.52416.5
      Dampness
      ‘Do not know’ was answered by 1 woman.
       No20375.89376.211075.3
       Yes, during past 12 months2910.81310.71611.0
       Yes, 1–3 years ago145.254.196.2
       Yes, >3 years ago228.2119.0117.5
       Yes, any time6524.22923.83624.7
      Visible mold
       No24992.611594.313491.2
       Yes, during past 12 months83.032.553.4
       Yes, 1–3 years ago62.221.642.7
       Yes, >3 years ago62.221.642.7
       Yes, any time207.475.7138.8
      Mold odor (in the past 12 months)
       No24791.811392.713491.2
       Yes, almost daily62.221.642.7
       Yes, 1–3 days a week10.410.800
       Yes, 1–3 days a month51.921.632.0
       Yes, less often103.743.364.1
       Any exposure
      Exposure to mold odor at any frequency (almost daily, 1–3 days a week, 1–3 days a month, less often).
      228.297.3138.8
      Any exposure at home
      Exposure to at least one of the following: water damage, dampness, visible mold or mold odor.
      No18368.08468.99967.3
      Yes8632.03831.14832.7
      Any exposure at home or work
      Exposure to at least one of the following: water damage, dampness, visible mold or mold odor.
      No14353.26654.17752.4
      Yes12646.85645.97047.6
      a Exposure to mold odor at any frequency (almost daily, 1–3 days a week, 1–3 days a month, less often).
      b Exposure to at least one of the following: water damage, dampness, visible mold or mold odor.
      c ‘Do not know’ was answered by 1 woman.

      Dampness and mold exposures and lung function

      In the analyses adjusting for all covariates and including eight exposure variables for home and work dampness or mold, FEV1 level was reduced on average 200 ml related to mold odor at home (effect estimate −0.20, 95% CI −0.60 to 0.21) and FVC level was reduced on average 460 ml (−0.46, −0.95 to 0.03) respectively (Table 3). These did not reach statistical significance, although the upper confidence limit for effect estimate of FVC level was close to 0. In the four exposure variable model, exposure to mold odor at home or at work or both was related to reduced FEV1 (−0.15, −0.42 to 0.12) and FVC (−0.22, −0.55 to 0.11) levels.
      Table 3Exposure to dampness and mold and lung function (n = 269).
      Exposure indicatorsFEV1
      Adjusted for age, sex, height, education, smoking (current, ex), and second hand smoke exposure.
      (l)
      FVC
      Adjusted for age, sex, height, education, smoking (current, ex), and second hand smoke exposure.
      (l)
      Effect estimate95% CIEffect estimate95% CI
      8 exposure indicators in the model
      Home
       Water damage0.009−0.25 to 0.270.04−0.27 to 0.36
       Dampness0.004−0.19 to 0.20−0.01−0.25 to 0.22
       Visible mold−0.15−1.12 to 0.810.17−1.00 to 1.33
       Mold odor−0.20−0.60 to 0.21−0.46−0.95 to 0.03
      Work
       Water damage−0.18−0.55 to 0.19−0.20−0.65 to 0.24
       Dampness−0.13−0.36 to 0.10−0.14−0.42 to 0.13
       Visible mold0.42−0.47 to 1.301.00−0.06 to 2.07
       Mold odor0.01−0.33 to 0.360.10−0.31 to 0.52
      4 exposure indicators in the model
      Home or work or both
       Water damage−0.07−0.29 to 0.14−0.07−0.33 to 0.19
       Dampness−0.08−0.24 to 0.07−0.10−0.29 to 0.09
       Visible mold0.08−0.55 to 0.710.52−0.25 to 1.29
       Mold odor−0.15−0.42 to 0.12−0.22−0.55 to 0.11
      a Adjusted for age, sex, height, education, smoking (current, ex), and second hand smoke exposure.
      We also performed similar analyses separately for men and women. Strongest association was found among women between home exposure and lung function levels. They had on average 510 ml reduced FEV1 levels (−0.51, −1.0 to 0.03) and 820 ml reduced FVC levels (−0.82, −1.4 to −0.20) related to mold odor exposure at home (Tables 4 and 5).
      Table 4Exposure to dampness and mold and FEV1 and FVC in men (n = 122) and women (N = 147).
      Exposure indicatorFEV1
      Adjusted for age, height, education, smoking (current, ex), and second hand smoke exposure.
      (l)
      FVC
      Adjusted for age, height, education, smoking (current, ex), and second hand smoke exposure.
      (l)
      Effect estimate95% CIEffect estimate95% CI
      Men (8 indicators)
      At home
       Water damage−0.03−0.52 to 0.460.24−0.36 to 0.83
       Dampness−0.09−0.43 to 0.26−0.02−0.44 to 0.40
       Visible mold
       Mold odor0.03−0.62 to 0.69−0.09−0.89 to 0.70
      At work
       Water damage−0.64−1.72 to 0.44−0.22−1.54 to 1.09
       Dampness−0.15−0.53 to 0.23−0.29−0.76 to 0.18
       Visible mold0.38−0.69 to 1.440.97−0.33 to 2.28
       Mold odor0.02−0.54 to 0.570.08−0.60 to 0.76
      Men (4 indicators)
      At home or at work or both
       Water damage−0.15−0.59 to 0.300.14−0.40 to 0.69
       Dampness−0.19−0.47 to 0.09−0.21−0.56 to 0.13
       Visible mold0.35−0.70 to 1.400.95−0.34 to 2.24
       Mold odor−0.06−0.50 to 0.39−0.09−0.63 to 0.46
      Women (8 indicators)
      At home
       Water damage−0.005−0.30 to 0.29−0.15−0.49 to 0.18
       Dampness0.04−0.21 to 0.28−0.016−0.30 to 0.27
       Visible mold−0.34−1.20 to 0.520.09−0.90 to 1.10
       Mold odor−0.51−1.04 to 0.03−0.82−1.44 to −0.20
      At work
       Water damage−0.07−0.42 to 0.27−0.17−0.58 to 0.23
       Dampness−0.14−0.43 to 0.14−0.01−0.35 to 0.32
       Visible mold
       Mold odor−0.05−0.49 to 0.390.10−0.41 to 0.61
      Women (4 indicators)
      At home or at work or both
       Water damage−0.03−0.25 to 0.20−0.16−0.42 to 0.11
       Dampness−0.04−0.23 to 0.15−0.02−0.24to 0.21
       Visible mold−0.39−1.21 to 0.440.10−0.86 to 1.07
       Mold odor−0.23−0.58 to 0.11−0.27−0.67 to 0.14
      a Adjusted for age, height, education, smoking (current, ex), and second hand smoke exposure.
      Table 5Low and high exposure to mold odor at home or at work or both and lung function.
      Exposure to mold odorFEV1 (l)FVC (l)
      Effect estimate95% CIEffect estimate95% CI
      At home or at work
      Adjusted for age, sex, height, education, smoking (current, ex), and second hand smoke exposure.
      (n = 269)
      Low−0.14−0.35 to 0.07−0.12−0.37 to 0.14
      High−0.01−0.22 to 0.19−0.05−0.30 to 0.20
      Any exposure to water damage, dampness, visible mold at home or at work or both0.05−0.06 to 0.170.03−0.11 to 0.16
      Men
      Adjusted for age, height, education, smoking (current, ex), and second hand smoke exposure.
      (n = 122)
      Low−0.16−0.55 to 0.23−0.06−0.55 to 0.42
      High−0.08−0.47 to 0.30−0.12−0.59 to 0.36
      Any exposure to water damage, dampness, visible mold at home or at work or both0.05−0.15 to 0.250.03−0.21 to 0.28
      Women
      Adjusted for age, height, education, smoking (current, ex), and second hand smoke exposure.
      (n = 147)
      Low−0.08−0.32 to 0.16−0.08−0.36 to 0.20
      High0.06−0.18 to 0.300.02−0.25 to 0.30
      Any exposure to water damage, dampness, visible mold at home or at work or both0.03−0.10 to 0.16−0.01−0.16 to 0.14
      a Adjusted for age, sex, height, education, smoking (current, ex), and second hand smoke exposure.
      b Adjusted for age, height, education, smoking (current, ex), and second hand smoke exposure.

      Discussion

      The main finding of our population-based study of working aged adults is that mold odor at home or at work or both was related to a reduced lung function levels. FEV1 was on average 200 ml lower (effect estimate −0.20, 95% CI −0.60 to 0.21) and FVC on average 460 ml lower (−0.46, −0.95 to 0.03) in those exposed compared to those without exposure. Among women the corresponding reduction was more pronounced with an average 510 ml reduction in FEV1 levels (−0.51, −1.0 to 0.031) and 820 ml in FVC levels (−0.82, −1.4 to −0.20), reaching statistical significance.

      Validity of results

      Questionnaire-based exposure information may include some misclassification. Several studies have compared the occupant reported presence of indoor dampness and/or mold problems with findings in building inspections or measurements of fungi in indoor dust, as reviewed by Jaakkola and Jaakkola [
      • Jaakkola M.S.
      • Jaakkola J.J.K.
      Indoor molds and asthma in adults.
      ]. Most of the studies have shown relatively good agreement between these methods of exposure assessment. In general it has been found that subjects tend to underestimate dampness/mold problems at home compared to inspection or dust mold measurements, and this trend has been observed among both in asthmatics and in healthy subjects. Nondifferential misclassification of exposure is likely to lead to some underestimation of the true effect related to indoor mold problems. On the other hand, dust measurements and inspection usually reflect just one point in time, while occupant report may reflect better long term exposures that are more relevant to health effects. Reponen et al. reported that air concentrations of endotoxin and β-D-glucan were consistently higher in homes with moldy odor [
      • Reponen T.
      • Singh U.
      • Schaffer C.
      • Vesper S.
      • Johansson E.
      • Adhikari A.
      • et al.
      Visually observed mold and moldy odor versus quantitatively measured microbial exposure in homes.
      ]. Our outcome of interest was objectively measured lung function level which is not sensitive to bias. We were able to adjust for a number of potential confounders including sex, age, height, education, smoking and exposure to secondhand smoke, in regression analysis to eliminate these factors as potential explanations for our results.

      Synthesis with the previous knowledge

      We conducted a systematic literature search and found only four previous papers assessing the associations between dampness or mold exposures and lung function levels in adults with no lung diseases [
      • Vojdani A.
      • Campbell A.W.
      • Kashanian A.
      • Vojdani E.
      Antibodies against molds and mycotoxins following exposure to toxigenic fungi in a water-damaged building.
      ,
      • Stark H.J.
      • Randell J.T.
      • Hirvonen M.-R.
      • Purokivi M.K.
      • Roponen M.H.
      • Tukiainen H.O.
      The effects of Aspergillus fumigatus challenge on exhaled and nasal NO levels.
      ,
      • Kilburn K.
      Neurobehavioral and pulmonary impairment in 105 adults with indoor exposure to molds compared to 100 exposed to chemicals.
      ,
      • Norbäck D.
      • Zock J.-P.
      • Plana E.
      • Heinrich J.
      • Svanes C.
      • Sunyer J.
      • et al.
      Lung function decline in relation to mould and dampness in the home: the longitudinal European Community Respiratory Health Survey ECRHS II.
      ]. In some of these studies individuals reported musty odor but none of those assessed separately an association between mold odor and lung function levels. All four studies presented some evidence of a reduction in lung function levels due to exposure to mold or dampness. Consistently with the present results, the ECRHS study found an association mainly among women [
      • Norbäck D.
      • Zock J.-P.
      • Plana E.
      • Heinrich J.
      • Svanes C.
      • Sunyer J.
      • et al.
      Lung function decline in relation to mould and dampness in the home: the longitudinal European Community Respiratory Health Survey ECRHS II.
      ]. In a previous study of 40 mold-exposed cases and 40 age and sex matched controls, 60% of cases and 0% of controls had abnormal lung function test results [
      • Vojdani A.
      • Campbell A.W.
      • Kashanian A.
      • Vojdani E.
      Antibodies against molds and mycotoxins following exposure to toxigenic fungi in a water-damaged building.
      ]. In a Finnish case–control study, the baseline FVC and FEV1% predicted were significantly lower among the mold-exposed subjects when compared with the other groups (p = 0.046 and p = 0.004, respectively) [
      • Stark H.J.
      • Randell J.T.
      • Hirvonen M.-R.
      • Purokivi M.K.
      • Roponen M.H.
      • Tukiainen H.O.
      The effects of Aspergillus fumigatus challenge on exhaled and nasal NO levels.
      ]. In a cohort study of 6443 patients, after excluding the asthmatic patients, there was an association among women between lung function decline and reported water damage in the last 12 months (n = 2989: additional decline in FEV1 −2.89 ml; 95% CI −5.36 to −0.41 ml), and with dampness score >0 (additional decline −3.00 ml; 95% CI −5.00 to −0.99 ml) when comparing to those with a dampness score = 0. There were no similar associations seen among non-asthmatic men [
      • Norbäck D.
      • Zock J.-P.
      • Plana E.
      • Heinrich J.
      • Svanes C.
      • Sunyer J.
      • et al.
      Lung function decline in relation to mould and dampness in the home: the longitudinal European Community Respiratory Health Survey ECRHS II.
      ]. In a case–control study of 105 mold-exposed cases and 202 non-exposed controls there was a significantly lower FVC and FEV1 levels among cases [
      • Kilburn K.
      Neurobehavioral and pulmonary impairment in 105 adults with indoor exposure to molds compared to 100 exposed to chemicals.
      ].

      Conclusions

      Our results provide evidence that exposure to mold odor is related to lower lung function levels among non-asthmatic adults, especially among women.

      Conflict of interest statement

      None declared.

      Acknowledgment

      This study was funded by the Academy of Finland (grants no. 138691 and no. 266314, and grant no. 129419 of SALVE research program) and the Ministry of Social Affairs and Health of Finland (grant no. STM/1523/2012).

      References

        • World Health Organization (WHO) Europe
        Guidelines for indoor air quality: dampness and mold.
        World Health Organization, Copenhagen2009
        • Institute of Medicine
        Damp indoor spaces and health.
        National Academies Press, Washington, DC2004
        • Jaakkola M.S.
        • Haverinen-Shaugnessy U.
        • Douwes J.
        • Nevalainen A.
        Indoor dampness and mold problems in homes and asthma onset in children.
        in: Braubach M. Jacobs D.E. Ormandy D. Environmental burden of disease associated with inadequate housing – a method guide to the quantification of health effects of selected housing risks in the WHO European Region. World Health Organization, Geneva2011: 5-31
        • Haverinen-Shaugnessy U.
        Prevalence of dampness and mold in European housing stock.
        J Expo Sci Environ Epidemiol. 2012; 22: 461-467
        • Quansah R.
        • Jaakkola M.S.
        • Hugg T.T.
        • Heikkinen S.A.M.
        • Jaakkola J.J.K.
        Residential dampness and molds and the risk of developing asthma: a systematic review and meta-analysis.
        PLoS One. 2012; 7 (Available:) ([accessed 02.07.13]): e47526
        • Jaakkola M.S.
        • Quansah R.
        • Hugg T.T.
        • Heikkinen S.A.M.
        • Jaakkola J.J.K.
        Association of indoor dampness and molds with rhinitis risk: a systematic review and meta-analysis.
        J Allergy Clin Immunol. 2013; 132: 1099-1110
        • Vojdani A.
        • Campbell A.W.
        • Kashanian A.
        • Vojdani E.
        Antibodies against molds and mycotoxins following exposure to toxigenic fungi in a water-damaged building.
        Arch Environ Health. 2003; 58: 324-336
        • Stark H.J.
        • Randell J.T.
        • Hirvonen M.-R.
        • Purokivi M.K.
        • Roponen M.H.
        • Tukiainen H.O.
        The effects of Aspergillus fumigatus challenge on exhaled and nasal NO levels.
        Eur Respir J. 2005; 26: 887-893
        • Kilburn K.
        Neurobehavioral and pulmonary impairment in 105 adults with indoor exposure to molds compared to 100 exposed to chemicals.
        Toxicol Ind Health. 2009; 25: 681-692
        • Norbäck D.
        • Zock J.-P.
        • Plana E.
        • Heinrich J.
        • Svanes C.
        • Sunyer J.
        • et al.
        Lung function decline in relation to mould and dampness in the home: the longitudinal European Community Respiratory Health Survey ECRHS II.
        Thorax. 2011; 66: 396-401
        • Jaakkola M.S.
        • Nordman H.
        • Piipari R.
        • Uitti J.
        • Laitinen J.
        • Karjalainen A.
        • et al.
        Indoor dampness and molds and development of adult-onset asthma: a population-based incident case–control study.
        Environ Health Perspect. 2002; 110: 543-547
        • Jaakkola J.J.K.
        • Jaakkola N.
        • Piipari R.
        • Jaakkola M.S.
        Pets, parental atopy, and asthma in adults.
        J Allergy Clin Immunol. 2002; 109: 784-788
        • Jaakkola M.S.
        • Piipari R.
        • Jaakkola N.
        • Jaakkola J.J.K.
        Environmental tobacco smoke and adult onset-asthma: a population-based incident case-control study.
        Am J Public Health. 2003; 93: 2055-2060
        • Jaakkola J.J.K.
        • Piipari R.
        • Jaakkola M.S.
        Occupation and asthma: a population-based incident case-control study.
        Am J Epidemiol. 2003; 158: 981-987
        • Jaakkola M.S.
        • Ieromnimon A.
        • Jaakkola J.J.K.
        Are atopy and specific IgE to mites and molds important for adult asthma?.
        J Allergy Clin Immunol. 2006; 117: 642-648
        • Jaakkola J.J.K.
        • Ieromnimon A.
        • Jaakkola M.S.
        Interior surface materials and asthma in adults: a population-based incident case-control study.
        Am J Epidemiol. 2006; 164: 742-749
        • Jaakkola M.S.
        • Jaakkola J.J.K.
        Office work exposures and adult-onset asthma.
        Environ Health Perspect. 2007; 115: 1007-1011
        • Rantala A.
        • Jaakkola J.J.K.
        • Jaakkola M.S.
        Respiratory infections precede adult-onset asthma.
        PLoS One. 2011; 6 ([accessed 02.07.13]): e27912
        • Lajunen T.K.
        • Jaakkola J.J.K.
        • Jaakkola M.S.
        Influence of heredity on asthma continues into adulthood.
        J Allergy Clin Immunol. 2013; 131: 916-918
        • Jaakkola J.J.K.
        • Jaakkola N.
        • Ruotsalainen R.
        Home dampness and molds as determinants of respiratory symptoms and asthma in pre-school children.
        J Expo Anal Environ Epidemiol. 1993; 3: 129-142
        • Ruotsalainen R.
        • Jaakkola N.
        • Jaakkola J.J.K.
        Dampness and molds in day-care centers as an occupational health problem.
        Int Arch Occup Environ Health. 1995; 66: 369-437
        • Jaakkola J.J.K.
        • Hwang B.F.
        • Jaakkola M.S.
        Home dampness and molds as determinants of allergic rhinitis in childhood: a 6-year, population-based cohort study.
        Am J Epidemiol. 2010; 172: 451-459
        • American Thoracic Society
        Standardization of spirometry, 1994 update.
        Am J Respir Crit Care Med. 1995; 152: 1107-1136
        • Viljanen A.A.
        • Halttunen P.K.
        • Kreus K.-E.
        • Viljanen B.C.
        Spirometric studies in non-smoking, healthy adults.
        Scand J Clin Lab Invest. 1982; 42: 5-20
        • Piipari R.
        • Jaakkola J.J.K.
        • Jaakkola N.
        • Jaakkola M.S.
        Smoking and asthma in adults.
        Eur Respir J. 2004; 24: 734-739
        • Jaakkola M.S.
        • Jaakkola J.J.K.
        Indoor molds and asthma in adults.
        Adv Appl Microbiol. 2004; 55: 309-338
        • Reponen T.
        • Singh U.
        • Schaffer C.
        • Vesper S.
        • Johansson E.
        • Adhikari A.
        • et al.
        Visually observed mold and moldy odor versus quantitatively measured microbial exposure in homes.
        Sci Total Environ. 2010; 408: 5565-5574