Early-life exposure to phthalates among infants in Italy: characterization and time trends

BACKGROUND AND AIM: Human exposure to phthalates, endocrine disruptors, and reproductive toxicants, is ubiquitous. Urine is the matrix of choice for biomonitoring and in utero exposure is well documented. Evidence of early life exposure to phthalates is scarce. The aim of this study is to assess phthalate exposure and its changes over time in a cohort of healthy infants in the province of Modena, Italy. METHODS: In this prospective birth-cohort study, we assessed phthalate exposure(8 metabolites of 6 phthalates)in urine samples collected from mothers just after delivery and in infants at birth, 3 and 6 months using phthalate-free bags. Mother-infant pairs were enrolled in a university hospital in Modena(Italy) between January 2019 and May 2020. After solid-phase extraction, samples were analyzed by triple Quad LC/MS Mass Spectrometry. RESULTS: 188 mother-infant pairs were enrolled. MEP was always detectable and showed the highest levels, increasing over time. MMP and DEHP metabolites showed as well an increasing trend, however, they were detected at lower levels, while MnBP and MBzP showed intermediate concentrations and decreasing trends over time. Significant associations between mother-infant pairs at birth were found only for a few metabolites(MMP, MEP, and MnBP). Infant levels at 3 and 6 months appeared more related, suggesting a continuative exposure to these chemicals inside the indoor environment. CONCLUSIONS: Phthalate exposure appears wide and extended over time. Infants were exposed to several phthalates, including those more toxic and strictly regulated in infant toys, personal care products and food contact materials in the European Union. Their unregulated use in other consumers’products, building and decorating materials or home furniture may explain the potential exposure of at-risk groups, such as infants or pregnant women. To effectively protect the most vulnerable subjects, public health preventive and regulatory actions should address this specific issue as well.