Adverse Respiratory Effects From Prenatal Exposure to Phenols and Phthalates in Young Boys

In utero exposure to select phenols and phthalates adversely affected respiratory health in boys until aged 5 years, according to a study published in Environmental Health Perspectives.

Researchers from the EDEN Mother-Child Cohort Study noted that phenols and phthalates are produced in large volumes, including bisphenol A, which is found in food packaging and epoxy resins; parabens, benzophenone-3, and triclosan, which are found in cosmetics, sunscreens, and antibacterial soaps; while some dichlorophenols are intermediates in the production of herbicides and room deodorizers.

Phthalates are primarily used as plasticizers and may be found in many items, such as polyvinyl chloride flooring, toys, and food packaging. Some phthalates are used in soaps, nail polish, lotions, fragrances, and as excipients in pharmaceuticals.

It has been postulated that due to the immaturity of the lungs and immune system and the physiology of development, prenatal exposure to such chemicals could have long-term adverse effects on respiratory health.

Of the 587 pregnant women from the cohort who delivered a boy, the investigators measured 9 phenols and 11 phthalate metabolites in spot pregnancy urine samples. Respiratory outcomes were evaluated by questionnaires until age 5, when forced expiratory volume in 1 second (FEV₁) was determined by spirometry. Ethyl-paraben showed an association with increased asthma rate (hazard ratio [HR], 1.10; 95% CI, –1.24 to 0.05) and was negatively associated with FEV₁ while bisphenol A was associated with increased rates of asthma diagnosis (HR, 1.23; 95% CI, 0.97-1.55) and bronchiolitis/bronchitis (HR, 1.13; 95% CI, 0.99-1.30). Isolated trends were found for wheezing between 2.5 dichlorophenol and monocarboxynonyl phthalate.

The researchers noted that because no information was gathered on postnatal exposure, respiratory effects could be potentially due to postnatal and not specifically prenatal exposures. However, these results are supported by the findings of previous studies in mice and in both boys and girls that have demonstrated an association between prenatal exposure to bisphenol A and increased allergic sensitization and bronchial inflammation.

Reference

Vernet C, Pin I, Giorgis-Allemand L, et al. In utero exposure to select phenols and phthalates and respiratory health in five-year-old boys: a prospective study. Environ Health Perspect. 2017. doi:10.1289/EHP1015