Assessing bioaccumulation of Pb, Cd, and As in goats: Impacts of exposure to mine tailings in a polymetallic mining region

• Published in: Journal of South American earth sciences 2025-02, Vol.153, p.105372, Article 105372
• Main Authors: Salgado-Souto, Sergio Adrián, Escorcia-Reynoso, Martín Ubaldo, Del Rio-Salas, Rafael, Talavera-Mendoza, Oscar, Bottini-Luzardo, María Benedicta, Núñez-Martínez, Guadalupe, Aguirre-Noyola, José Luis, Hernández-Flores, Giovanni
• Format: Article
• Language: English
• Subjects: Consumer food safety; Goat edible tissues; Health risk; Pb isotopes; Toxic elements
• ISSN: 0895-9811
• DOI: 10.1016/j.jsames.2025.105372

Pb, Cd, and As concentrations were measured in blood, edible tissues, urine, feces, and hair samples from goats raised in the vicinity of the abandoned El Fraile mine tailings (Taxco de Alarcón, Mexico) to evaluate the bioaccumulation levels to Pb, Cd, and As. The goats were fed grains, grasses and shoots that grew on top of the mine tailings and drank mine leachate for seven months, replicating the conditions under which local goatherds typically raise their goats in the region. Blood showed the lowest Pb, Cd, and As concentrations, followed by edible tissues (leg muscle, brain, and lungs) whose concentrations were below Mexican permissible limits (NOM-004-ZOO-1994). However, according to Codex Alimentarius, kidney and rumen tissues showed concentration barely above the Pb limits, and kidney tissues were above the limits of Cd. Moreover, urine showed higher concentrations of Pb and As, while feces had even higher concentrations. However, hair and bezoars exhibited the highest Pb, Cd, and As values. The data suggest that consumption of edible tissues poses only a minimal risk to human health. However, the Pb, Cd, and As concentrations found in the tissues of the rumen, liver, and kidney, as well as urine, feces, and hair, indicate that goats experienced exposure to toxic elements, possibly resulting in chronic poisoning. Additionally, isotope data indicate that Pb determined in blood, urine, and bezoars is related to the remnant mineralization present in the mine tailings, highlighting the hazard that mine tailings represent to the environment and settlers of the region. [Display omitted] •Pb, Cd, and As concentrations in edible tissue of goats do not exceed recommended values.•Pb, Cd, and As values in urine, faces, and hair indicate toxic elements exposure.•Pb isotope ratios in urine, blood, and hair indicate the contribution of toxic elements from mine tailings.•El Fraile mine tailings influence the presence of toxic elements in the living beings of the region.