Occupational respiratory morbidity and associated factors among hairdressers in Ethiopia: a cross-sectional study

OBJECTIVE

This study was designed to determine the prevalence and factors associated with occupational respiratory morbidity among hairdressers in Northwestern Ethiopia.

DESIGN

A cross-sectional study was conducted from 6 July 2022 to 17 August 2022. The data were collected using a standardised American Thoracic Society questionnaire. The collected data were entered into EpiData V.4.6 and analysed using Stata V.14. A multivariable logistic regression analysis was conducted to identify factors associated with occupational respiratory morbidity. The association was determined using an adjusted OR (AOR) with a 95% CI at a p value of <0.05.

SETTING

The study was conducted in Gondar city, Northwestern Ethiopia.

PARTICIPANTS

A total of 403 hairdressers participated in this study.

OUTCOME MEASURES

The primary outcome is the prevalence of occupational respiratory morbidity.

RESULTS

The total response rate was 95.5%. The majority, 250 (62%) of the respondents were women. The mean age (±SD) of the respondents was 27 (±6.0) years. The overall prevalence of occupational respiratory morbidity during the past 12 months was found to be 134 (33.3%) (95% CI (28.7% to 38.1%)). Female hairdressers (18.6%) showed greater respiratory morbidity than male hairdressers (14.7%). Working experience 3-5 years (AOR: 3.05; 95% CI (1.76 to 5.30)) and working experience >5 years (AOR: 6.22; 95% CI (2.73 to 14.16)), overweight (body mass index (BMI)) (AOR: 3.01; 95% CI (1.19 to 7.58)) and working near roadsides (AOR: 2.15; 95% CI (1.33 to 3.37)) were risk factors of occupational respiratory morbidity among hairdressers.

CONCLUSIONS

This study concluded that one-third of hairdressers experienced occupational respiratory morbidity. Longer work experience, higher BMI and working near roadsides were identified as significant risk factors for respiratory morbidity in hairdressers. Dietary calorie restrictions for overweight individuals and the development and implementation of air pollution mitigation measures targeted at roadside workers are advised to curb the problem.

Hair straightening products and the risk of occupational formaldehyde exposure in hairstylists

Hair straitening products are widely used by hairstylists. Many keratin-based hair smoothing products contain formaldehyde. This study aimed to investigate occupational formaldehyde exposure among hairstylists dealing with hair straightening products and the relation between genotoxicity biomarkers and the short-term formaldehyde exposure concentrations and the working years. The study was carried out in Cairo, Egypt on 60 hairstylists use hair straightening products divided into two groups according to the working years. All hairstylists were subjected to micronucleus (MN) frequencies in both epithelial buccal cells (EBC) and peripheral blood lymphocytes (PBL). Fifteen-minute (min) formaldehyde exposure concentrations were measured at workplace during hair straightening procedure. Fifteen-minute formaldehyde concentrations in both groups exceeded the National Institute for Occupational Safety and Health and the American Conference of Governmental Industrial Hygienist thresholds levels. The MN frequencies in EBC and PBL showed a significant increase in group II in comparison to control and group I, which in turn showed a significant increase in MN frequency in PBL and a nonsignificant increase in the MN frequency in EBC when compared to control. A positive correlation was found between genotoxicity biomarkers and working years. Occupational exposures to hair straightening products in the studied hairstylist were found to expose them to formaldehyde concentrations that exceeded the standard limits. All selected genotoxicity biomarkers showed a significant increase in exposed workers and were positively correlated to the duration of exposure.

Environmental and biological monitoring of occupational formaldehyde exposure resulting from the use of products for hair straightening

The evaluation of formaldehyde (FD) exposure in beauty salons, due to the use of hair straightening products, and its relation with genotoxicity biomarkers was performed in this study. Regardless of official recommendations, the inappropriate use of homemade hair creams has became a popular practice in Brazil, and high formaldehyde content in the "progressive straightening" creams can contain mutagens that could increase the incidence of neoplasia in those people who use them. Damage to DNA was assessed by conducting a micronuclei test (MNT) on buccal cells and the comet assay on heparinized venous blood samples. A total of 50 volunteers were recruited at six different beauty salons (labeled A to F). At two salons that used products that did not contain FD (salons D and E), environmental FD concentrations were 0.04 and 0.02 ppm. In contrast, the products used at salons A, B, C, and F contained 5.7, 2.61, 5.9, and 5.79% of FD, and these salons had environmental FD concentrations of 0.07, 0.14, 0.16, and 0.14 ppm, respectively. Comparison of the beauty salon workers from each of the six beauty salons revealed significant differences in urinary formic acid (FA) concentration before exposure (p = 0.016), urinary FA after exposure (p = 0.004), variation in FA concentration before and after exposure (p = 0.018), environmental FD concentration (p < 0.001), cytogenetic damage detected by the comet assay according to both damage index (p < 0.001) and frequency of damage (p < 0.001), and for karyorrhexis only according to the MNT (p = 0.001).