Reproductive disorders in hairdressers and cosmetologists: a meta-analytical approach

The cost of beauty: Perspectives of salon workers in Kisumu City, Kenya

Despite occupational exposure to hazardous chemicals in cosmetics and personal care products (PCPs), salon workers receive minimal formal protections. Consequently, most salon workers rely on personal safeguards. However, the nature of such individual-level safeguards remains unknown. Knowledge of risks associated with occupational use of cosmetics and PCPs and information needs of salon workers were investigated in Kisumu City, Kenya. Responses from 302 respondents showed that 84% were women and 30% had post-secondary education. Seventy percent reported knowing that ingestion, inhalation, dermal absorption, and injection are the pathways through which harmful products in cosmetics and PCPs may enter the body. Salon workers who had been employed for more than 5 years were at least twice more likely to report that it is not the case that cosmetics and PCPs only cause harm to children (5-10 years vs 1 year: OR = 2.440, 95% CI, 1.160-5.239; >10 years vs 1 year: OR = 8.857, 95% CI, 3.163-29.377); they were about three times more likely to either agree with the statement that cosmetics and PCPs only cause harm under prolonged exposure or to say that they did not know compared to their counterparts who had worked in the industry for 1 year (5-10 years vs 1 year: OR = 2.750, 95% CI, 1.144-7.179; >10 years vs 1 year: 3.179, 95% CI, 1.173-9.096). Over 50% of the respondents reported that they need information on how to protect themselves and others; on available protective measures; and on cosmetic products and PCPs that are safe. Sixty percent reported that they would prefer to get such information from the Ministry of Health at the county or national level and on product inserts. Overall, salon workers in Kisumu City are knowledgeable about the risks associated with their occupation but also appreciate gaps in their knowledge, which can be filled by government-mandated interventions.

Inhalational exposure to formaldehyde, carcinogenic, and non-carcinogenic risk assessment: A systematic review

Formaldehyde is one of the most widely used substances in a variety of industries, although it was classified as a human carcinogen by the International Agency for Research on Cancer (IARC). The present systematic review was conducted to retrieve studies related to occupational exposure to formaldehyde until November 2, 2022. Aims of the study were to identify workplaces exposed to formaldehyde, to investigate the formaldehyde concentrations in various occupations and to evaluate carcinogenic and non-carcinogenic risks caused by respiratory exposure to this chemical among workers. A systematic search was done in Scopus, PubMed and Web of Science databases to find the studies done in this field. In this review, studies that did not meet the criteria specified by Population, Exposure, Comparator, and Outcomes (PECO) approach were excluded. In addition, the inclusion of studies dealing with the biological monitoring of FA in the body and review studies, conference articles, books, and letters to the editors were avoided. The quality of the selected studies was also evaluated using the Joanna Briggs Institute (JBI) checklist for analytic-cross-sectional studies. Finally, 828 studies were found, and after the investigations, 35 articles were included in this study. The results revealed that the highest formaldehyde concentrations were observed in waterpipe cafes (1,620,000 μg/m³) and anatomy and pathology laboratories (4237.5 μg/m³). Carcinogenic and non-carcinogenic risk indicated the potential health effects for employees due to respiratory exposure as acceptable levels of CR = 1.00 × 10^-4 and HQ = 1, respectively were reported to be exceeded in more than 71% and 28.57% of the investigated studies. Therefore, according to the confirmation of formaldehyde's adverse health effects, it is necessary to adopt targeted strategies to reduce or eliminate exposure to this compound from the occupational usage.

Para-phenylenediamine deteriorates oocyte quality by impairing mitochondrial function

Several studies demonstrate that para-phenylenediamine (PPD) is often added to permanent oxidative hair dyes. Sub-chronic topical exposure to PPD in male rats damages their testicular function; however, little is known about the effects of PPD exposure on the female reproductive system, especially on oocyte quality. In this study, we found that PPD can affect the meiotic capacity of oocytes and their fertilization potential. In particular, PPD can damage the spindle/chromosome structure and prevent oocytes from developing and maturing normally. Furthermore, PPD exposure compromised the dynamics of cortical granules and their component, ovastacin. In addition to the protein level of Juno, the sperm receptors on the egg membrane, were substantially impaired in PPD-administered oocytes, thus leading to fertilization failure. Finally, we found that PPD exposure resulted in abnormal mitochondrial function, which led to oocyte degeneration, apoptosis, and increased ROS levels. Altogether, our study illustrates that mitochondrial dysfunction and redox perturbation are the major causes of the poor quality of oocytes exposed to PPD.

Association of hairdressing with cancer and reproductive diseases: A systematic review

OBJECTIVES

To review recent epidemiological studies investigating carcinogenic or reprotoxic effects among hairdressers who seem to be at greater risk for systemic adverse effects of chemicals released from hair care products than consumers.

METHODS

A systematic review according to the PRISMA-P guidelines was performed and included studies published from 2000 to August 2021, in which cancer or adverse reproductive effects were diagnosed in 1995 and onward. Data were synthetized qualitatively due to the small number of studies, heterogeneity of study designs, outcomes, and methods.

RESULTS

Four studies investigating cancer frequencies and six studies investigating effects on reproduction among hairdressers were identified. All were of good quality and with low risk of bias. Only one of the four studies found an increased risk of cancer reporting nine times higher odds for bladder cancer in hairdressers than the population-based controls. Three other studies investigating bladder and lung cancer, and non-Hodgins lymphoma did not find an increased risk in hairdressers. Regarding reprotoxic effects, numerous outcomes were investigated including menstrual disorders, congenital malformations, fetal loss, small-for-gestational age newborns, preterm delivery, and infertility. Increased risk was found for ventricular septal defect in newborns of fathers working as hairdressers. Furthermore, several indices of poor neonatal or maternal health were significantly associated with mothers working as hairdresser.

CONCLUSIONS

Despite the scarce evidence that hairdressers are at increased risk of carcinogenic or reprotoxic effects related to their trade, such health risks cannot be ruled out. Therefore, preventive efforts to diminish occupational exposures to hairdressing chemicals should be targeted.

Association between Maternal Exposure to Chemicals during Pregnancy and the Risk of Foetal Death: The Japan Environment and Children's Study

Scarce knowledge is available on the relationship between maternal chemical exposure during pregnancy and foetal deaths. We studied the association of spontaneous abortions and stillbirths with occupational or daily maternal exposure to chemicals commonly used by pregnant women. Data from the Japan Environment and Children’s Study (JECS), a nationwide prospective birth cohort study, were used. The participants of the study were asked about the frequency of their use of gasoline, pesticides, hair dye, and chlorine bleach during the first and the second to third trimesters of pregnancy. We investigated the relationship between the frequency of the use of chemicals and foetal death. Of the 104,065 foetuses, 923 (0.91%) were spontaneous abortions and 379 (0.37%) were stillbirths. Any type of exposure during the first trimester was not significantly associated with spontaneous abortions. Nevertheless, a more than weekly occupational use of hair dye from the first to the second/third trimester was significantly associated with stillbirth. The results of this study suggest that the frequent use of hair dye during pregnancy can have severe adverse effects on the foetus. These findings can help pregnant women, especially hairdressers, refrain from the continuous use of hair dyes.

Phthalates, ovarian function and fertility in adulthood

Phthalates are a family of high-production volume industrial chemicals used in the manufacture of plastics. Some phthalates are regulated as endocrine disrupting chemicals (EDCs) and reproductive toxicants based on adverse effects in the male. Potential effects in females are less understood although exposure levels can be higher in women compared to men. Here, we review the literature on the effects of phthalate exposures in adulthood on ovarian function and fertility in women. Experimental studies using cell cultures and rodents combined with human evidence from epidemiological studies suggest that phthalates pose a hazard to ovaries. Phthalates can disrupt follicle growth pattern, increase oxidative stress and cause follicle death. These effects could lead to infertility, faster depletion of ovarian reserve, and earlier reproductive senescence. However, more studies using more realistic exposure levels will be needed to properly assess the risks in women.

Perception of Environmental Risks and Behavioral Changes during Pregnancy: A Cross-Sectional Study of French Postpartum Women

Limiting exposure to environmental hazards during preconception and pregnancy is essential for preventing adverse pregnancy outcomes or developmental defects in offspring. However, the perception of environmental risk and the behavioral changes of women planning or having a pregnancy have rarely been investigated, except for a few risk factors. We thus performed a cross-sectional study of French postpartum women hospitalized in the Bordeaux University Hospital in 2017 by proposing a self-administrated survey. The main objective was to assess their level of awareness concerning a large panel of environmental hazards and modifications in their behavior during pregnancy in occupational and household environments. Among the 121 respondents, most identified the environment as a major factor for a healthy pregnancy but recognized a lack of knowledge regarding environmental risk factors. The internet, television, and magazines were their main sources of information. Most women modified some of their practices at work or home. These measures were rarely implemented in consultation with a health practitioner, which raises concerns about the relevance of the adjustments made. Our findings highlight the need to improve the quality of information available to women and to help them implement preventive measures in consultation with physicians.

The effect of pre-pregnancy hair dye exposure on infant birth weight: a nested case-control study

Background

Limited evidences were reported about the risk of pre-pregnancy hair dye use or irregular menstruation with abnormal birth weight during pregnancy, and their joint effects were also unknown. The aim of our study was to explore whether the pre-pregnancy exposure of hair dye and irregular menstruation were associated with the risk of abnormal birth weight.

Methods

We conducted a nested case-control study from a prospective cohort of 6203 pregnant women. Low birth weight study included 315 mother-infant pairs (105 LBW cases and 210 matched controls), and macrosomia study included 381 mother-infant pairs (127 macrosomia cases and 254 matched controls). Meanwhile, lifestyle information including hair dying custom and menstrual history were collected by face-to-face questionnaires and birth outcomes were extracted from the medical records. The logistic regressions models were used to analyze the join effect of irregular menstruation and hair dye use.

Results

Pre-pregnancy hair dye use was associated with increased risk of LBW (adjusted OR = 1.71, 95% CI: 1.01–2.92, P = 0.048). Irregular menstruation had high risk of LBW (adjusted OR = 2.79, 95% CI: 1.53–5.09, P = 0.001) and macrosomia (adjusted OR = 1.93, 95% CI: 1.09–3.44, P = 0.023). Additionally, in the LBW study, women who used hair dye with pre-pregnancy BMI < 18.5 kg/m² had higher OR than those with only one risk factor (3.07 vs 2.53, P_trend = 0.015), and women with both hair dye use and irregular menstruation also had higher risk than those with only one factor (4.53 vs 2.07, P_trend = 0.05). Moreover, in macrosomia study, women with irregular menstruation and pre-pregnancy BMI ≥ 24 kg/m² had higher risk than those with one factor (13.31 vs 2.09, P_trend = 0.001).

Conclusion

Our study showed that either pre-pregnancy hair dye use or irregular menstruation was associated with abnormal birth weight, especially, their joint effects could furthermore increase the risk of low birth weight infants when these two factors existed simultaneously.