Prenatal exposure to heavy metals is known to be associated with adverse birth outcomes and oxidative stress biomarkers. In this study, we examined whether maternal free cortisol or 8-Hydroxy-2-Deoxyguanosine (8-OHdG) could mediate associations between maternal heavy metal exposure and birth outcomes. A total of 182 healthy pregnant women were recruited. Heavy metals (including Pb, Hg, and Cd), free-cortisol, and 8-OHdG were analyzed in urine at delivery. Birth outcomes including birth weight, length, Ponderal index, and head circumference were measured. To examine associations of maternal urinary heavy metals with biomarkers and birth outcomes, generalized linear models were employed. Birth length was positively associated with Pb (β = 0.78, 95% CI: 0.09–1.46) and Hg (β = 0.84, 95% CI: 0.23–1.45) (both p < 0.05). The Ponderal index, a measure of a newborn’s leanness, was negatively associated with maternal urinary Pb (β = −0.23, 95% CI: −0.46–−0.07) and Hg (β = −0.26, 95% CI: −0.44–−0.08) (both p < 0.05). No association between maternal Cd and birth outcomes was observed. Most heavy metals showed positive associations with free cortisol and 8-OHdG. Free cortisol was identified as a mediator underlying the observed relationship between Hg and birth length or Ponderal index. This study observed adverse birth outcomes from maternal exposures to Pb and Hg. Increased free cortisol related to Hg exposure was suggested as a possible causal pathway from Hg exposure to birth outcomes such as the Ponderal index.

Despite global restrictions like the Minamata Convention, heavy metal contamination in cosmetics remains a critical public health concern, with limited cross-country comparative data on heavy metal concentrations in cosmetics across Asian markets. We measured Hg, Pb, As, Cd, Sb, Cr, and Ni contents in 189 cosmetic products purchased in 2022 in Bangladesh, India, Indonesia, Korea, Malaysia, the Philippines, and Vietnam. Samples were screened by handheld X-ray fluorescence; Hg was quantified by a direct mercury analyzer and As, Cd, Cr, Ni, Pb, and Sb were quantified by ICP-OES. Principal component analysis (PCA) was used to characterize metal co-occurrence patterns, and Monte Carlo simulation was applied to estimate dermal systemic exposure dose, hazard quotients (HQ), and lifetime cancer risk (LCR). Mercury in face creams exhibited extreme heterogeneity (range: ND-67,000 mg/kg), while eye cosmetics contained elevated Arsenic levels (median 4.13 mg/kg). PCA distinctively separated Hg (PC2) from geogenic metals (As/Cr/Ni on PC1), suggesting intentional adulteration. Probabilistic risk estimates indicated upper-tail non-cancer risk for Hg in facial creams (95th percentile HQ 6.32; P[HQ>1] = 24.4%). As produced the highest LCR estimates (facial cream 95th percentile 2.60 × 10⁻⁴). These findings indicate product-type-specific metal patterns and highlight a subset of facial products with extreme Hg levels that can drive substantial upper-percentile risk, supporting the need for targeted market surveillance and enforcement.

Park J, et al. Ann Occup Environ Med. 2022 Jun;34:e12. https://doi.org/10.35371/aoem.2022.34.e12