Table 1.
Summary of the 10 epidemiologic studies on the relationships between exposure to phthalates and PVC materials and the risk of asthma, allergy, and related respiratory outcomes in adults, Medline search from 1950 through May 2007.
| Reference, location | Study design | Study population | Exposure | Outcomes | Results | Comment |
|---|---|---|---|---|---|---|
| Polakoff et al. (1975), USA | Cross-sectional study | 17 meat wrappers: 21 office personnel and store clerks as a reference group | Inhalation exposure to pyrolysis products of PVC film; assessment based on job category (meat wrappers exposed) and questionnaire information | Symptoms, signs based on questionnaire information; pre- and postshift spirometry: FVC, FEV1, PEF, FEF25, FEF50, FEF75, FEF90 | Exposed had a higher prevalence of cough ever (47.1% vs. 23.8%), work-related shortness of breath (23.5% vs. 0%), wheezing (5.9% vs. 0%), eye watering and itching (17.6% vs. 9.5%), nasal and pharyngeal symptoms (29.4% vs. 4.8%), allergies (11.8% vs. 9.5%), and decline over shift in FEV1 (p < 0.05) and FEF50 (p < 0.05) | Frequency matching of reference group but no adjustment for potential confounders |
| Falk and Portnoy (1976), Houston, TX, USA | Cross-sectional study | 145 meat wrappers; 150 checkers and 150 meat cutters as a reference group | Inhalation exposure to pyrolysis products of PVC film; assessment based on job category and interview information | Symptoms, signs based on questionnaire information | Symptom prevalences in exposed vs. checkers and cutters: shortness of breath (16% vs. 4% and 4%; p < 0.05), wheezing (12% vs. 5% and 7%; NS), chest pain (17% vs. 5% and 7%; p < 0.05), bronchitis (31% vs. 19% and 13% p < 0.01), pneumonia (36% vs. 27% and 9%; NS), and pleurisy (33% vs. 16% and 9%; p < 0.01) | Frequency matching of reference group but no adjustment for potential confounders |
| Andrasch et al. (1976), Portland, OR, USA | Cross-sectional study | 96 meat wrappers | Inhalation exposure to pyrolysis products of PVC film; assessment based on job title (meat wrappers exposed) and questionnaire information | Symptoms and signs based on questionnaire information (response rate, 58%); and on bronchial provocation test to PVC fumes and price-label adhesive fumes for 14 workers | 69% had work-related respiratory, mucosal, or system symptoms; 3 of 11 workers developed a mean decrease of 25% in FEV1 after exposure to PVC fumes; 9 of 13 workers developed a 49% decrease in FEV1 and 40% decrease in FVC after exposure to price-label adhesive fumes | 77% of symptomatic workers reported improvement on weekends and during vacations; no adjustment for potential confounders |
| Brooks and Vandervort (1977), Ohio, USA | Cross-sectional study | 44 workers in retail food industry: 24 exposed meat wrappers; 20 office workers and store clerks as a reference group | Inhalation exposure to pyrolysis products of PVC film and thermoactivated price-label adhesive fumes | Symptoms and signs based on questionnaire information, spirometry (FVC, FEV1, MMF, VC50, and VC25) | Exposed vs. reference: cough, 37% vs. 10%; dyspnea, 29% vs. 10%; wheezing, 12% vs. 0%; asthma/ allergy, 17% vs. 5%; nasal symptoms, 14% vs. 0%; no differences between pre- and postshift lung function tests | Exposed attributed symptoms to PVC film fumes rather than price-label adhesive fumes; no adjustment for potential confounders |
| Eisen et al. (1985), Boston, MA, USA | Cohort study | 83 workers in the retail food industry: 40 exposed to hot-wire or cool-rod fumes, and 43 as a reference group | Inhalation exposure to pyrolysis products of PVC film; assessment based on job title: meat wrappers, meat cutters, and delicatessen product workers exposed | Change in FEV1 over time (mL/year) | No difference in FEV1 change between the exposed and reference group; interaction term “hot-wire exposure* asthma/allergy,” 76 mL/year, p < 0.06 | Workers with asthma or allergy may be more susceptible; adjusted for age, smoking, and asthma/allergy |
| Markowitz (1989), Plainfield, NJ, USA | Cohort study | 86 firefighters: 66 exposed, 20 as a reference group | Exposed to burning PVC at a warehouse fire | Occurrence and severity of respiratory symptoms based on questionnaire information: cough, wheeze, shortness of breath, and chest pains 5–6 weeks and 22 months after exposure | Exposed scored significantly higher for all symptoms after 5–6 weeks and all except wheeze after 22 months | No adjustment for potential confounders |
| Nielsen et al. (1989), Denmark | Cross-sectional study | 39 workers in a PVC processing plant: 20 exposed employed as machine attendants and calendar operators, 19 unexposed | Exposed to PVC thermal degradation products and phthalic acid esters | Symptoms, signs based on questionnaire information, bronchial provocation test, specific serum IgGs and IgEs, spirometry (VC, FEV1, FEF50, FEF75) | Exposed vs. reference: conjunctivitis, 25% vs. 0% (p < 0.02); rhinitis, 20% vs. 10%; unspecific bronchial hyperreactivity, 25% vs. 5%; dry cough, 45% vs. 0% (p < 0.001); asthma, 10% vs. 0%; one positive reaction in bronchial provocation; one exposed had IgG against phthalic anhydride; no differences in lung function parameters | Adjustment for age, height, and smoking habits |
| Norbäck et al. (2000), Sweden | Cross-sectional study | 87 workers in four hospitals: 50 residing in exposed buildings and 37 residing in reference buildings | Two exposed buildings with signs of dampness-related degradation of DEHP in PVC flooring and presence of 2-ethyl-1-hexanol in indoor air; two reference buildings | Doctor-administered questionnaire on presence of asthma symptoms, wheezing, and/or attacks of breathlessness | Exposed (yes/no): asthma symptoms, AOR, 8.6 (95% CI, 1.3–56.7) | Adjusted for sex, age, atopy, current smoking, building dampness at home and at work |
| Tuomainen et al. (2004), Finland | Repeated cross- sectional study before and after intervention | Office building with 148 workers: first survey, 92 participants; second survey, 115 participants | Before intervention: damp and damaged PVC flooring, 1–3 μg 2-ethyl-1-hexanol per cubic meter of air | Questionnaire information on symptoms and perceived air quality | Index office vs. national rates: eight new cases of asthma in 4 years, 9.2 times more than expected | Intervention included removal of floor coverings, adhesives, and smoothing layers |
| Jaakkola et al. (2006), southern Finland | Population-based incident case– control study | 521 new cases of asthma (21–63 years of age), and 932 population controls | Questionnaire information on presence of plastic wall paper and flooring in the home | Standardized clinical diagnosis of asthma based on history, bronchial challenge, and PEF monitoring | Asthma AOR (95% CI): plastic wall materials at work, < 50% surface vs. none, 1.26 (0.49–3.22); ≥ 50% surface vs. none, 2.43 (1.03–5.75); PVC flooring at work, 1.13 (0.84–1.51) | Adjusted for sex, age, education, smoking, ETS, other surface materials at home and at work |
Abbreviations: AOR, adjusted OR; ETS, environmental tobacco smoke; FEF50, forced expiratory flow at 50% of vital capacity; FEF75, forced expiratory flow at 75%; FEF90, forced expiratory flow at 90%; FEV1, forced expiratory flow in 1 sec; FVC, forced vital capacity; MMF, maximal midexpiratory flow; NS, not significant; PEF, peak expiratory flow; VC, vital capacity; VC50, 50% vital capacity; V25, 25% vital capacity.