Human biomonitoring of metals in adults living near a waste-to-energy incinerator in ante-operam phase: Focus on reference values and health-based assessments.

The human biomonitoring (HBM) of metals is a part of the ongoing project SPoTT for the longitudinal health surveillance of the population living near a waste-to-energy (WTE) incinerator (Turin, Italy). The HBM of metals in the SPoTT population aimed to evaluate: i) reference values (RVs) before the WTE incinerator started operation; ii) differences in exposure by variables; iii) variations respect to other HBM studies; iv) exposure that exceeds the available health-based benchmarks as the Biomonitoring Equivalents (BEs) for urine Cd and Human Biomonitoring (HBM-I and HBM-II) values for urine Hg, Tl, and blood Pb; v) risk assessment by generating hazard quotients (HQs) for the single metal and hazard index (HI) for the co-occurrence of metals. Eighteen metals in urine and Pb in blood were determined by sector field inductively coupled plasma mass spectrometry. Metal concentrations were comparable with RVs reported in other countries, except for slightly higher As, Be, Ir, Pd, Pt, Rh, and Tl levels. Smoking was associated with Cd; age with Pb; drinking bottled water with As and Cd; consumption of fish with As and Hg; amalgams with Hg and Sn; dental restorations with Pd and Pt; use of jewelry with Co and Rh, and piercing with Ni. While HQs for urine Cd, Hg, Tl and blood Pb suggested that adverse effects were unlikely, the HQ value raised the question of whether additive interactions of these metals could produce health concern. The obtained HBM data can be an early warning for accumulations of metals and identification of subgroups at risk.

Children exposure to inorganic and organic arsenic metabolites: A cohort study in Northeast Italy.

The aim of this study was to provide urinary levels of total arsenic (TAs) and As species as arsenobetaine (AsB), arsenocholine (AsC), inorganic As (i.e., [As(III)+As(V)]), methylarsonic acid (MMA) and dimethylarsinic acid (DMA) in 7 year-old-children (n = 200) enrolled in the Northern Adriatic Cohort II (NACII), a prospective cohort in a coastal area of Northeast Italy. TAs was determined by sector field-inductively coupled plasma mass spectrometry (SF-ICP-MS) and AsB, AsC, As(III), As(V), MMA and DMA by ion chromatography coupled to ICP-MS (IC-ICP-MS). The geometric mean (GM) for TAs was 12.9 µg/L and for [iAs + MMA + DMA] was 4.26 µg/L. The species AsB (GM of 5.09 µg/L) and DMA (GM of 3.20 µg/L) had the greatest percentage contribution to TAs levels; a greater percentage contribution from AsB is seen at TAs >10 µg/L and from DMA at TAs <10 µg/L. Urinary [iAs + MMA] levels were positively associated with [iAs + MMA + DMA] and DMA with AsB levels. Fish, shellfish and crustaceans consumption increased the AsB and TAs levels, while rice intake, mothers' education level and selenium (Se) concentration influenced the DMA concentration. Children have a high capacity to metabolize and detoxify the iAs because of the higher secondary methylation index (ratio DMA/MMA) with respect to primary methylation index (ratio MMA/iAs). In addition, the median level of [iAs + MMA + DMA] in the whole population of children was lower than the Biomonitoring Equivalent (BE) value for non-cancer endpoints. Also the Margin of Safety (MOS) value based on the population median was greater than 1, thus the exposure to the toxicologically relevant As species was not likely to be of concern.