The association of voice problems with exposure to indoor air contaminants in health care centres – the effect of remediation on symptom prevalence: A follow-up study

Voice problems are common in occupations where there is noise, dust, odours or fumes and microbial contamination. The purpose of this study is to find out the prevalence of hoarseness, its changes over the follow-up and the effect of the remediation on the prevalence. A total of 13 health care buildings were followed, 10 with indoor air problems and 3 as reference buildings. Three buildings were thoroughly remediated, and their effects were analyzed. A health questionnaire was used, before and after the remediation. Blood samples and skin prick tests were performed on all volunteers. Based on findings, 17.0% of the respondents reported hoarseness at least every week. The skin test findings for common environmental allergens, moisture damage microbes and mites were approximately similar in the exposed and reference groups, respectively. Hoarseness had a strong correlation with indoor air problems. Before the remediation, hoarseness and voice problems were more prevalent in the problem buildings. After the remediation, hoarseness was reduced by 50%. In conclusion, this study shows a connection between indoor air exposure and technical damage in buildings. The remediation significantly reduced the prevalence of hoarseness. Mould allergy is rare and does not explain the voice problems.