Self-reported symptoms in Swedish hairdressers and association with exposure to volatile organic compounds (VOCs), including aldehydes

(2023) 23:1576 Ricklund et al. BMC Public Health https://doi.org/10.1186/s12889-023-16446-5 RESEARCH ARTICLE BMC Public Health Open Access Self‑reported symptoms in Swedish hairdressers and association with exposure to volatile organic compounds (VOCs), including aldehydes Niklas Ricklund1* , Ing‑Liss Bryngelsson1 and Jessika Hagberg2 Abstract Background Working as a hairdresser involves combined exposure to multiple chemicals in hair treatment products that may induce symptoms in airways and skin. Methods In this cross-sectional study, perceived symptoms among Swedish hairdressers at 10 hair salons were surveyed through a questionnaire. Associations with personal exposure to volatile organic compounds (VOCs), includ‑ ing aldehydes, and their corresponding hazard index (HI), based on the estimated risk for non-cancer health effects, were examined. The prevalence of four out of 11 symptoms was compared to available reference datasets from two other studies of office workers and school staff. Results All 11 surveyed symptoms were reported among the hairdressers (n = 38). For the whole study group, the most prevalent symptoms were dripping nose (n = 7) and headache (n = 7), followed by eczema (n = 6), stuffed nose (n = 5), cough (n = 5) and discomfort with strong odors (n = 5). Significant relationships between exposure and symp‑ toms were scarce. The exception was total VOC (TVOC) exposure adjusted to worked years in the profession; a dif‑ ference was observed for any symptom between hairdressers in the group with 20 + years compared to 0–5 years in the profession (logistic regression, OR 0.03, 95% CI 0.001–0.70). Out of the four symptoms available for compari‑ son, the prevalence of headache and cough was significantly higher in hairdressers than in controls (OR 5.18, 95% CI 1.86–13.43 and OR 4.68, 95% CI 1.17–16.07, respectively). Conclusions Adverse health effects related to occupation was common among the hairdressers, implying a need for exposure control measures in hair salons. Symptoms of headache and cough were more frequently reported by hairdressers than staff in offices and schools. A healthy worker effect among the hairdressers was indicated in the group with 20 + years compared to 0–5 years in the profession. Significant relationships between measured exposure and symptoms were scarce but gave information about advantages and disadvantages of the different exposure measures. The study design could be improved by increasing the size of the study population, using a bet‑ ter match of reference data and increasing the applicability and representability over time of the measured exposure. Keywords Indoor air quality, Healthy worker effect, Risk assessment, Hazard index, Hair salon, Airway symptom *Correspondence: Niklas Ricklund Full list of author information is available at the end of the article © The Author(s) 2023. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecom‑ mons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data. Ricklund et al. BMC Public Health (2023) 23:1576 Background Working as a hairdresser involves combined exposure to multiple chemicals in hair treatment products that may induce various symptoms. In Swedish hairdressers, an increased occupational risk of symptoms has been shown for hand eczema [1], asthma [2] and airway symptoms [3, 4]. An international review of literature between 2014–2019 on exposures among hair and nail salon workers concluded that there was consistent evidence of an increased risk of respiratory effects [5]. Other types of health effects from occupational exposure have also been studied, e.g., reproductive health effects [5, 6], endocrine effects [5] and cancer in different organs [7–13], but conclusions about relationships have so far been inconsistent. The complexity of chemical exposure in hair salons and variety of symptoms that may be induced in hairdressers necessitate viable and robust methods of risk assessment. For risk assessment of non-cancer health effects from combined exposure to multiple chemicals via indoor air in hair salons, a hazard index (HI) approach was proposed by de Gennaro et al. [14]. The approach concerned volatile organic compounds (VOCs) that are constituents of most hair treatment products. The HI was based on the sum of quotients of measured VOC indoor air concentrations and their corresponding reference values, i.e., concentration below which chronic exposure to a single VOC is unlikely to cause non-cancer health effects. The HI approach was also applied in a recent Swedish study of hairdressers, where an excessive exposure risk was found in four out of 10 hair salons [15]. The HI approach is in line with recommendations in the WHO/IPCS framework concerning a general methodology for risk assessment of combined exposure to multiple chemicals [16] and has been applied in other indoor environments, e.g., homes, schools and offices [17], beauty salons [18], and preschools and primary schools [19, 20]. The main objectives of the present study were to monitor perceived symptoms among a cross-section of Swedish hairdressers and to assess associations with exposure to VOCs, including aldehydes, and their corresponding HI based on the estimated risk for non-cancer health effects. Methods Study design A cross-sectional study of the prevalence of self-reported perceived symptoms in hairdressers was conducted in spring 2017 in Örebro County, Sweden. For some of the surveyed symptoms, the prevalence could be compared with reference datasets from two other studies of symptoms in office workers and school staff [21, 22]. Furthermore, associations between the symptoms and personal Page 2 of 11 chemical exposure were assessed. Data on chemical exposure were obtained from measurements conducted in hair salons previously reported by Ricklund et al. [15]. Ethical approval for the study was granted by the Swedish Ethical Review Authority (decision no 2017/414). Study group For the questionnaire survey, a total of 38 hairdressers distributed over 10 hair sa (...truncated)