An ultra-high performance liquid chromatography tandem mass spectrometry method was developed and validated for the sensitive determination and unambiguous confirmation of residues of per and polyfluorinated alkyl substances (PFAS) in breastmilk, retail milk and infant formulas following two sample preparation methods. Sample pre-treatment was carried out by a simplified QuEChERS method without requiring dSPE or any further clean-up. The method was validated in accordance with the requirements of Commission Decision 657/2002/EC with slight modifications. The method displayed good linearity with R² ranging from 0.9843–0.9998 for all target PFAS. The recovery and within-laboratory reproducibility of the method (n = 63) were in the range 60–121% and 5–28%, respectively. The decision limit, detection capability and limit of quantitation ranged from 30–60 ng kg⁻¹ to 40–100 ng kg⁻¹ and 5–50 ng kg⁻¹, respectively. Acceptable matrix effect values in the range −45–29% were obtained with uncertainty of measurement lower than 25% for all target PFAS. The method displays its suitability for the sensitive and high-throughput confirmatory analysis of C₄–C₁₄ PFAS in breastmilk, dairy milk and infant formulas.

While breast milk is the recommended food for infants up to at least six months, exogenously derived compounds such as trace elements have been widely reported in human milk which may make it become toxic or a source of pollutants to the infants. Numerous short- and long-term health effects have been associated with high body—burdens of trace elements, which are amplified in infants. The current study determined the levels and possible contributing factors of six trace elements in breast milk of nursing mothers from a local hospital in Pretoria. Extraction of trace elements employed a digestion technique using perchloric and nitric acid in a ratio of 1:3, while Inductively Coupled Plasma–Membrane Spectrophotometry was used to identify and quantify their levels in breast milk. Concentrations of Cr and Mn were the highest in breast milk, with values ranging from 0.30 to 5.72 µg/L and 0.23 to 5.13 µg/L, respectively. Levels of Co, As, Pb and Cd ranged from <LOD to 0.2 µg/L, <LOD to 2.29 µg/L, 0.05 to 1.06 µg/L, and 0.004 to 0.005 µg/L, respectively. Levels of Cr, Mn and As were higher than the recommended limits from WHO (World Health Organization) in some milk samples. Dietary assessments showed minimal risk for the infants through breastfeeding at this stage; however, prolonged exposure to other sources of these toxic trace elements may pose a serious health risk for the infants. The nature of employment, infant birth weight, passive smoking and maternal diet were the significant factors noted to contribute to trace metal levels in breast milk.

Prevalence of geophagia and its contributing factors among pregnant women at Dr. George Mukhari Academic Hospital, Pretoria

Exposure to endocrine disruptors during early childhood poses significant health risks. This study examines the exposure levels of French 3.5-year-old children to various persistent and non-persistent pollutants and pesticides using hair analysis as part of the ELFE national birth cohort. Differences in sex and geographical location among the children were investigated as ppossible determinants of exposure. Exposure biomarkers from 32 chemical families were analyzed using LC-MS/MS and GC-MS/MS in 222 hair samples from children in the ELFE cohort. Of these, 46 mother-child pairs from the same cohort provided unique insight into prenatal and postnatal exposure. Regressions, correlations and discriminate analysis were used to assess relationships between exposure and possible confounding factors. Among the biomarkers tested in children's hair samples, 69 had a detection frequency of ≥ 50 %, with 20 showing a 100 % detection rate. The most detected biomarkers belonged to the bisphenol, organochlorine and organophosphate families. Sex-specific differences were observed for 26 biomarkers, indicating the role of the child's sex in exposure levels. Additionally, regional differences were noted, with Hexachlorobenzene varying significantly across the different French regions. Nicotine presented both the highest concentration (16303 pg/mg) and highest median concentration (81 pg/mg) measured in the children's hair. Statistically significant correlations between the levels of biomarkers found in the hair samples of the mothers and their respective children were observed for fipronil (correlation coefficient = 0.32, p = 0.03), fipronil sulfone (correlation coefficient = 0.34, p = 0.02) and azoxystrobin (correlation coefficient = 0.29, p = 0.05). The study highlights the elevated exposure levels of young children to various pollutants, highlighting the influence of sex and geography. Hair analysis emerges as a crucial tool for monitoring endocrine disruptors, offering insights into exposure risks and reinforcing the need for protective measures against these harmful substances.