Summary of epidemiological studies (chronological order) assessing the associations between cleaning occupation, tasks or agents and asthma in population-based and workforce-based studies
| Author, year | Country | Period of data collection | Study design | Study population | Method of data collection | Covariates | Type of exposure | Findings (95% CI in parenthesis) | GRADE score |
| Kogevinas et al, 199916 | 26 centres in 12 countries | 1992 | Population-based survey (ECRHS) | 15 637 people randomly selected from the general population (n=443 cleaners) | Asthma was assessed by methacholine challenge test and questionnaire | Age, sex, smoking status, study centre | Cleaning occupation | BHR and asthma symptoms or medications: OR=1.97 (1.33–2.92) Asthma symptoms or medication: OR=1.82 (1.44–2.30) | Medium |
| Zock et al, 200122 | Spain | 1998 | Population-based cross-sectional (ECRHS) | 67 indoor cleaners, 1272 office workers | Questionnaire, blood samples for serum IgE | Age, gender, smoking, study centre | Confirmed cleaners | BHR and asthma symptoms or medications: OR=2.8 (1.3–6.2) Asthma symptoms or medication: OR=1.7 (1.1–2.6) Higher PRs for private home cleaners | Moderate |
| Karjalainen et al, 200215 | Finland | 1986–1998 | Registry-based cohort | 53 708 cleaners, 202 751 administrative managerial and clerical workers | The Medication Reimbursement Register of the SII of Finland and the Finnish Register of Occupational Diseases (FROD) | Age, follow-up period | Female cleaners | WRA: RR=1.50 (1.43–1.57) | High |
| Zock et al, 200223 | 11 European countries and three outside Europe | 1990–1994 | Population-based survey (ECRHS Stage II) | 304 cleaners, 4492 office workers | Questionnaire, blood samples for serum IgE | Age, gender, smoking, study centre | Cleaning occupation | Current asthma OR=2.47 (1.7–3.6) | Moderate |
| Jaakkola et al, 200314 | Finland | 1997–2000 | Population-based case-control | 521 asthma cases, 932 controls | Questionnaire | Age, gender, smoking | Female cleaners | OA: OR=1.42 (0.81–2.48) | Moderate |
| Medina-Ramón et al, 200319 | Spain | 2000–2001 | Population-based cross-sectional | 4521 female domestic cleaners, 593 current, 1170 former | Questionnaire | Age, smoking | Current and former cleaning | Ever cleaning for current asthma: OR=1.73 (1.44–2.07) Current cleaner for current asthma: OR=1.32 (1.04–1.69) Current cleaner for current asthma (domestic only) : OR=1.46 (1.10–1.92) Former cleaner for current asthma: OR=2.00 (1.63 to 2.43) | High |
| Le Moual et al, 200418 | France | 1975 | Population-based survey | 404 cleaners, 8428 administrative service workers | Questionnaire ISCO-88 JEM | Age, gender, smoking | Cleaning occupation Generic asthmagens | WRA, cleaning job: OR=1.04 (0.70–1.54) WRA, cleaning agents: OR=2.16 (1.12–4.17) | Moderate |
| Delclos et al, 200726 | USA | 2003 | Workforce-based cross-sectional | 3650 healthcare professionals (862 physicians, 941 nurses, 968 occupational therapists, 879 respiratory therapists) | Questionnaire | Age, sex, race/ethnicity, professional group, years as a health professional (‘seniority’), smoking, obesity | Exposure to cleaning agents/tasks Seniority: 10–16 years 17–26 years ≥27 years | WRA Medical instrument cleaning: OR=2.22 (1.34–3.67) General cleaning: OR=2.02 (1.20–3.40) Use of powdered latex gloves between 1992 and 2000: OR=2.17 (1.27–3.73) Administration of aerosolised medications: OR=1.72 (1.05–2.83) OR=2.08 (0.64–6.73) OR=3.37 (1.10–10.26) OR=4.10 (1.39–12.11) | High |
| Kogevinas et al, 200717 | 13 countries | 1998–2003 | Population-based cohort (ECRHS-II) | 6837 (358 of them cleaners) | ECRHS II questionnaire | Age, sex, smoking, centre | Cleaning and caretaking Cleaning products using asthma-specific JEM | Cleaning and caretaking occupation: OR=1.71 (0.92–3.17) Exposure to cleaning products: OR=1.80 (1.01–3.18) | High |
| Mirabelli et al, 200720 | 22 centres located in 10 European countries | 1998–1999 | Population-based cohort (ECRHS-II) | 332 nurses or employed in nursing-related job, 2481 professional or administrative workers | Questionnaire ISCO-88 | Age, country, sex, smoking, study area | Exposure to cleaning products, cleaning tasks among healthcare workers | New-onset asthma Ammonia and/or bleach: OR=2.16 (1.03–4.53) Liquid multi-use products: OR=1.16 (0.61–2.19) Washing powders OR=1.65 (0.77–3.53) Any products in spray form OR=2.36 (0.99–5.64) | High |
| Obadia et al, 200929 | Canada | Not specified | Workforce-based cross-sectional | 566 cleaners and 587 other building workers | Questionnaire | Age, gender, smoking | School or racetrack public building cleaners | OA, males OR=0.93 (0.4–2.3) OA, females: OR=1.00 (0.4–2.3) | High |
| Eng et al, 201012 | New Zealand | 2004–2006 | Population-based cross-sectional | 3055 participants (from a random sample of 10,000) | Telephone survey | Age, gender, smoking, deprivation | Cleaners | WRA, adult onset: OR=1.3 (0.8–2.1) WRA, current: OR=1.60 (1.09–2.35 | Moderate |
| Vizcaya et al, 201130 | Spain | 2007–2008 | Cross-sectional study on employees of cleaning companies | 917 employees of 37 cleaning companies: 761 current cleaners, 86 former and 70 never cleaners (referents) | Spirometry during clinic visit | Age, gender, nationality. smoking status | Cleaning occupation Cleaning products | Current asthma, current cleaners: OR=1.9 (0.5–7.8), former cleaners: OR=1.9 (0.6–5.5) Adult-onset asthma, current cleaners: OR=1.4 (0.4–4.9), former cleaners: OR=2.5 (0.5–12) Use of hydrochloric acid: OR=1.7 (1.1–2.6) | Moderate |
| Arif and Delclos, 201225 | USA | 2004–2005 | Workforce-based cross-sectional | 3650 healthcare professionals | Questionnaire (exposure to cleaning substances) In the longest held job | Age, sex, race/ethnicity, BMI, seniority, atopy, smoking status | Cleaning agents | WRA symptoms increased in a dose-dependent manner from OR=2.64 (95% CI 0.57 to 12.1) for 1/week exposure to cleaning agents to OR=5.37 (1.43–20.16) for >1/day. For exposures to disinfectants/sterilising agents, WEA increased from 3.75 to 5.06 to 9.02 for at least 1/week, every day and more than once a day, respectively. OA for every day and >1/day self-reported exposure to cleaning agents: 0.81 (0.17–3.86) | High |
| Dumas et al, 201227 | France | 2003–2007 | Workforce-based case-control | 179 hospital workers, 545 controls, selected from a previous case-control study | Questionnaires, expert assessment and the asthma JEM | Gender, BMI | Among hospital workers: frequency of cleaning tasks: (never,<1, 1–3, 4–7 days/week | In women, for exposure >1 day/week (expert only): OR=1.04 (0.64–1.70); high intensity: OR=1.45 (0.81–2.62) In women, for exposure (expert +JEM) to high intensity cleaning/disinfecting tasks: OR=2.32 (1.11–4.86). Moderate/high exposure to quaternary ammonium: OR=1.93 (0.85–4.40) | High |
| h, 2013 | Great Britain | 1991–2000 | Population-based cohort | Cleaners unspecified: 156 Domestic helpers and cleaners: 113 Helpers and cleaners in offices, hotels: 516 | Interview | Gender, smoking, father’s social class, area of residence at 42 years, hay fever/allergic rhinitis in childhood | Domestic cleaners identified and coded using the ISCO-88 Cleaning products using asthma-specific JEM | Adult onset asthma in cleaners unspecified: OR=1.58 (0.95–2.63) Domestic helpers and cleaners: OR=1.79 (1.02–3.14) Helpers and cleaners in offices, hotels: OR=1.82 (1.34–2.48) Cleaning/disinfecting products: OR=1.67 (1.26–2.22) | High |
| Gonzalez et al, 201428 | France | 2006–2007 | Workforce-based cross-sectional | 543 healthcare workers (94 cleaners) | Questionnaire | Age, gender, smoking, atopy, BMI | Hospital cleaners | WRA, cleaning profession: crude OR=2.38 (0.48–11.85) OA, crude OR=2.33 (0.52–10.44) General cleaning tasks: adjusted OR=2.26 (0.95–5.35) | Moderate |
| Svanes et al, 201521 | Norway, Sweden, Denmark, Iceland, Estonia | 2010–2012 | Population-based cross-sectional (RHINE III), extension of ECRHS) | 2138 ever cleaners (from 13 499 respondents) | Questionnaire | Age, gender, smoking, educational level, parent’s educational level, BMI, centre | Occupational cleaner (ever | OA OR=1.47 (1.22–1.27) Positive trend with duration of exposure | High |
| Abrahamsen et al, 201724 | Norway | February to August 2013 | Population-based cross-sectional study | 185 cleaners (among 16 099 responders) | Questionnaire | Age, gender, area of residence, smoking, home damp/mould, housing conditions | Female and male cleaners JEM | Current asthma: OR=1.4 (0.61–3.2) Physician diagnosed asthma (ever): OR=0.92 (0.51–1.60) | Medium |
| Brooks et al, 202031 | New Zealand | 2008–2010 | Workforce-based cross-sectional | 425 cleaners, 281 reference workers | Questionnaires, bronchodilator | Age, gender, ethnicity, smoking | Cleaners | Current asthma in cleaners: OR=1.83 (1.18–2.85) Physician-diagnosed asthma ever: OR=0.62 (0.42–0.92) | High |
| Dumas et al, 202032 | USA | 2009–2015 | Workforce-based prospective cohort study (NHSII) | 116 429 female registered nurses | Questionnaires | Age, smoking status and pack-years, race, ethnicity, and BMI | Disinfectants Sprays for cleaning, disinfection, other JEM | OA Exposure to any disinfectant: HR=1.12 (0.91‐1.38) Weekly use of sprays: HR=1.10 (0.76‐1.59) | High |
ECRHS, European Community Respiratory Health Survey; ISCO, International Standard Classification of Occupations; JEM, job-exposure matrix; NHSII, Nurses’ Health Study II; OA, occupational asthma; PR, prevalence ratio; RHINE, respiratory health In northern Europe; WEA, work-exacerbated asthma; WRA, work-related asthma.