Monitoring of prenatal exposure to organic and inorganic contaminants using meconium from an Eastern Canada cohort.

Evaluating in utero exposure to inorganic and multiclass organic contaminants is critical to better evaluate potential harmful effects on prenatal and postnatal development. The analysis of meconium, the first bowel discharge of the newborn, has been proposed as a non-invasive way to assess cumulative prenatal exposure. The aim of this study was to implement an analytical method for quantifying 72 targeted organic compounds, including pesticides, pharmaceutical compounds and daily life xenobiotics, in meconium in addition to selected elements (17 elements). We report initial monitoring results based on the analysis of 396 meconium samples from an Eastern Canada cohort (Quebec, Canada). Element contents in meconium were analysed by mass spectrometry after digestion in nitric acid and peroxide. Targeted organic compounds were extracted and purified from meconium samples by a solid-liquid extraction followed by a dispersive-SPE purification before tandem mass spectrometry analysis. Concentrations of targeted elements were within the range of concentration reported in European and US studies but were lower than concentrations found in a developing country cohort (i.e., Pb, Cd). Out of the 72 targeted organic compounds, 31 were detected at least once and 30 were quantified. Compounds with the highest frequency of detection were caffeine, detected in all samples (from 2.80 to 6186 ng g-1), followed by acetaminophen detected in 53% of the samples (up to ~402 µg g-1) and methyl paraben detected in 20% of the samples (up to ~10 µg g-1). Pesticides were detected in low frequencies (< 2%) and low concentration (< 35 ng g-1). Results show that meconium can be used to monitor prenatal exposure of foetus to a wide array of inorganic and organic contaminants.