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Over centuries the mining industry has been accumulating a great quantity of wastes. The main potentially toxic elements present in the mining wastes are metals and metalloids. Due to its effects on human health, lead is one of the metals in wastes of more concern. Children are the most vulnerable to inorganic‐Pb exposure, due to their behavior and physiology. Therefore, the objective of this research was to determinate lead concentration and dispersion in an inhabited area, also to estimate the risk for children population in the site through the model IEUBK (Integrated Exposure Uptake Biokinetic model). The inorganic lead in dust present in the inhabited area was analytically determined. The risk assessment of lead exposure for children, predicted that is a probability from 31.68 to 90.61% of have lead in blood above of 10 μg dL−1. Remediation actions are recommended in order to mitigate the population exposure. A risk assessment is an important research tool to evaluate the level of population exposure to contaminant sources that can be dangerous for its health and quality of life. This research is significant due to the fact that tailing damps are multicontaminated wastes; moreover Pb is a pollutant that can generate harsh effects in people, especially in children. The lack of urban planning and awareness encouraged that settlements with new families were developed next to tailing damps without concern about the inhabitant's exposure to Pb and other metals. This manuscript proposes the use of models like the IEUBK, as a tool for risk assessment and studies related with urban planning in mining sites. © 2017 American Institute of Chemical Engineers Environ Prog, 37: 391–398, 2018 [ABSTRACT FROM AUTHOR]

Lead from historical mining and mineral processing activities may pose potential human health risks if materials with high concentrations of bioavailable lead minerals are released to the environment. Since the Joint Expert Committee on Food Additives of Food and Agriculture Organization/World Health Organization withdrew the Provisional Tolerable Weekly Intake of lead in 2011, an alternative method was required for lead exposure assessment. This study evaluated the potential lead hazard to young children (0–7 years) from a historical mining location at a semi-arid area using the U.S. EPA Integrated Exposure Uptake Biokinetic (IEUBK) Model, with selected site-specific input data. This study assessed lead exposure via the inhalation pathway for children living in a location affected by lead mining activities and with specific reference to semi-arid conditions and made comparison with the ingestion pathway by using the physiologically based extraction test for gastro-intestinal simulation. Sensitivity analysis for major IEUBK input parameters was conducted. Three groups of input parameters were classified according to the results of predicted blood concentrations. The modelled lead absorption attributed to the inhalation route was lower than 2 % (mean ± SE, 0.9 % ± 0.1 %) of all lead intake routes and was demonstrated as a less significant exposure pathway to children’s blood, compared with ingestion. Whilst dermal exposure was negligible, diet and ingestion of soil and dust were the dominant parameters in terms of children’s blood lead prediction. The exposure assessment identified the changing role of dietary intake when house lead loadings varied. Recommendations were also made to conduct comprehensive site-specific human health risk assessment in future studies of lead exposure under a semi-arid climate. [ABSTRACT FROM AUTHOR]

The concentration of lead in indoor dust is a key parameter in the Integrated Exposure Uptake Biokinetic (IEUBK) model used by the U.S. Environmental Protection Agency (USEPA) to evaluate risks to children from lead in soil. The default assumption is that the concentration of lead in indoor dust is 70% of the concentration of lead in outdoor soil. This report reviews the basis of this assumption, and compares the assumption to data obtained at mining/smelting Superfund sites in USEPA Region 8. Data for lead concentrations measured in both indoor dust and outdoor soil at a number of different properties at nine different Superfund sites were fit to a linear model (Cdust = K0 + Ksd·Csoil). Based on ordinary linear regression, values of Ksd ranged from 0.04 to 0.34. Values of Ksd estimated using a simple method to account for measurement errors yielded values from 0.04 to 0.35. These findings indicate that the concentration of lead in dust at mining/smelting sites in Region 8 is usually not as large as the IEUBK default assumption indicates. Use of the default is likely to be protective, but will likely result in an overestimation of childhood exposure and risk from lead in soil. [ABSTRACT FROM AUTHOR]

Lead pollution is an environmental priority. The evaluation of contaminated soils was often based on the results of the toxicity characteristic leaching procedure (TCLP) or the synthetic precipitation leaching procedure (SPLP). This paper presents a simple and fast screening test to detect soil contaminated by lead. The test is based on the chemistry of the stomach (Cl[sup -] concentration, pH 2, T = 37 °C) and simulates the incidental oral ingestion of soil by young children. The gastric juice simulation test (GJST) and the TCLP were applied to six size fractions from five soils. The GJST solubilized more Pb (up to 169 mg/l) than the TCLP especially for the smallest size fraction. Particle size had less effect on the TCLP. The percentage of lead released with the GJST, was most significant for the <63 µm size fraction and varied from 18 to 74% of the total lead content. Lead leached during the TCLP as a function of the total lead content showed poor linear regression coefficient (R) values for soils < 250 µm. R values were significant for all size fractions with the GJST. The pH of approximately 5 in the TCLP limits the solubilization of lead in the small size fractions. The five soils exceeded the toxicity threshold of 10 µgPb/dl of blood for a significant fraction of children between 0 and 36 months using the EPA's IEUBK model (Integrated Exposure Uptake Biokinetic). But the TCLP did not detect lead contamination in two of these five soils. The GJST proved to be a better estimator of lead bioaccessibility in the gastrointestinal tract. [ABSTRACT FROM AUTHOR]