A Job–Exposure Matrix for Potential Endocrine-disrupting Chemicals Developed for a Study into the Association between Maternal Occupational Exposure and Hypospadias

Abstract

A study to assess the association between the prevalence of hypospadias and maternal occupational exposure to potential endocrine-disrupting chemicals was carried out using data from the congenital anomaly register of the Office for National Statistics. The occupation of the mother is recorded in this register and to facilitate the assessment of maternal occupational exposure, a specific job-exposure matrix for potential endocrine-disrupting chemicals was developed. Seven categories of contaminants were evaluated (pesticides, polychlorinated organic compounds, phthalates, alkylphenolic compounds, bi-phenolic compounds, heavy metals and other substances). Maternal occupations were all coded using the 1980 version of Categories of Occupations. Three occupational hygienists assessed the likelihood of exposure (unlikely, possible, probable) to these seven substance groups for all 348 possible job titles independently. Almost 30% of the job titles were classified as exposed to at least one substance category (possible or probable), with approximately 16% of the job titles being probably exposed to at least one substance category. Some examples of occupations with probable exposure to potential endocrine-disrupting chemicals include: farm workers, electricians, workers in the plastics industry, painters, printers, hairdressers, dental practitioners, laboratory workers, textile workers and cleaners. It is recognized that there are a lot of limitations to the use of job-exposure matrices in general and with the matrix presented in this paper in particular. However, the matrix forms the basis on which further developments on occupational exposure assessment of potential endocrine-disrupting chemicals could be founded. In addition, the job-exposure matrix has identified areas where more exposure information is required. For example, exposure to potential endocrine-disrupting chemicals can occur in occupations such as hairdressing and workers in beauty salons, where the working population is more likely to be female and for which little data exist on levels of exposure.

Occupational exposure to endocrine-disrupting chemicals and the risk of uveal melanoma

“…Most JEM may have difficulties assessing exposures that may vary largely in-between individual workplaces and over time (23). Furthermore, the selection of possible EDC from reported exposures and work activities in this study was facilitated by our own experiences in designing a JEM with individual expert ratings on EDC exposure in the automobile industry (6) and by the availability of a community-based JEM from the UK focusing on exposure to EDC (4,5). By excluding next-of-kin or other surrogate interviews, we further increased the specificity of exposure assessment in these analyses.…”

“…We selected the following JSQ: dentistry, cooking and food preparing, dry cleaning, metal production and iron and steel coating, foundries, electroplating, wood working, pulp and paper production, textile industry, tanneries, slaughtering and meat processing, shoe and leather industry, electrical work, welding, glass production, ceramic production, rubber production, plastic production, painting, paint manufacture, and the chemical industry. Although the JSQ related to working in the ceramics and chemical industry did not directly solicit exposure to any endocrine agent, we decided to include these industries in the list of those with potential EDC exposure (5,10). Occupational exposure to pesticides in agriculture, animal husbandry, or forestry was not associated with an increased risk for uveal melanoma in a previous analysis of the Rare Cancer Study (19).…”

“…Possible mechanisms of EDC include mimicking of hormonal effects, antagonization of hormone receptors, disturbance of hormonal synthesis pathways, or other interferences with hormonal function. Research groups, including our own, attempted to classify occupational exposure to several EDC in job-exposure matrices (JEM) for community-or industry-based settings (4)(5)(6).…”

Maternal and Paternal Risk Factors for Cryptorchidism and Hypospadias: A Case–Control Study in Newborn Boys

“…The focus was on chemicals that may have endocrine activity (Van Tongeren et al 2002) or that have previously been described as male reproductive toxicants (Tielemans et al 1999a). For the few parents with multiple jobs, the job with most working hours was selected at the time of the first trimester (for mothers) or around fertilization (for fathers).…”

Risk of cryptorchidism and hypospadias among boys of maternal hairdressers – a Danish population-based cohort study

“…These compounds include hexane, benzene, toluene and metoxypropanol and endocrine-disruptive chemicals (EDC) (eg, alkylphenolic compounds and phthalates) (4)(5)(6). EDC exposures have shown associations with the genital diseases cryptorchidism (incomplete testicular descent) and hypospadias (displacement of the urethral opening along the ventral shaft of the penis) (7,8).…”