Phthalates and phenols are ubiquitous organic compounds found in hundreds of consumer products. Prenatal exposure to these chemicals have been associated with adverse health outcomes. Studies of these exposures during pregnancy and maternal and infant metabolome are scarce. To investigate the associations of phthalate and phenol chemical exposure with infant and maternal health outcomes, we conducted a cross-sectional study on 72 pregnant people and 63 infants in Cincinnati, Ohio. 

Phthalates are a group of diesters commonly used as solvents, plasticizers, and additives to improve the durability and flexibility of materials. They can be found in hundreds of consumer products, including food packaging, personal care products, cosmetics, and toys. Because phthalates are not covalently bound to plastics, they easily escape into the environment through evaporation, leaching, and abrasion. Phthalates can be acquired by humans through ingestion, inhalation, and dermal absorption, then proceed through various metabolic pathways. They can be absorbed by any part of the body and can cross the placenta, resulting in maternal to fetus transfer. The multiple sources and exposure routes make phthalate exposure pervasive in today’s consumer society. 

Phenols are a class of organic compounds described as Bisphenol A triclosans (BPAs) and are found in plastics, including everyday items such as shampoo, soaps, and toothpastes. Phenols can impact the metabolic processes of the endocrine system, which may result in hormone imbalances, cause reproductive issues, and lead to cancers such as ovarian, breast, and endometrial. Women exposed to phenols and phthalates in varying trimesters of pregnancy have an increased risk of developing hypertension, preterm birth, and gestational diabetes. Infant exposure is associated with an increased risk of developmental delays, including physical and behavioral impairment.

Maternal and newborn serum metabolome data used in this study were collected at delivery using ultra-high-performance liquid chromatography coupled with mass spectrometer (UHPLC-MS-MS). A cross-sectional analysis on the chemical exposure of the mother-infant pairs was done analyzing 8 phenol and 9 phthalate metabolites in maternal urine samples, excluding metabolites found to have exposure from medical tubing and delivery. Out of 75 mother-infant pairs, phenolic and phthalate metabolome data was available for 72 maternal serum samples and 63 cord serum samples. Associations between phenol and phthalate concentrations in maternal urinary samples and maternal/newborn metabolome data were assessed using linear regression adjusted for maternal and newborn factors while accounting for multiple testing with the Benjamini-Hochberg method to control for false discovery rate (FDR), with the FDR rate set to 0.2. A functional analysis was then performed to identify possible biological pathways.

There were various significant associations between phthalate and phenol chemical exposure and metabolome in the data analysis among the mother-infant dyads, indicating the potential adverse health outcomes related to exposure. There is evidence supporting the role of phenol and phthalate metabolites as endocrine disruptors, but future studies on the metabolome are needed to investigate pregnancy outcomes and examine long term effects on the metabolic system of mother-infant pairs. Precautionary measures to reduce exposure to phenols and phthalates are recommended to most vulnerable populations.