Screening-level assessment of potential toxicological risks from heavy metals in medicinal herbal infusions from central Peru

Zárate-Quiñones R.; Custodio M.; Damian-Alvarado R.; Cuadrado W.; Basaldúa-Galarza A.; Zúñiga-López D.; Avila-Chirinos A. · Heliyon (2026) · DOI: 10.1016/j.heliyon.2026.e45523

Resumen

Communities in the central Andes of Peru rely on ethnobotanical plants for their primary health care, consuming them mainly as herbal teas. These plants are exposed to heavy metal contamination from both geogenic and anthropogenic sources. The extent of heavy metal contamination and the associated risks to human health in the Mantaro River Valley are not yet fully understood. The objective of this study was to assess the concentrations and risks to human health of six target elements (As, Cr, Cu, Zn, Co, and Pb) in the leaves of five widely used medicinal species ( Matricaria chamomilla, Aloysia citrodora, Eucalyptus globulus, Schinus molle, and Minthostachys mollis ) in the agricultural districts of Chupuro and Pucará, in the Mantaro River Valley, Peru. The analyses were performed using inductively coupled plasma mass spectrometry (ICP-MS). The results showed that the leaves of E. globulus and M. mollis from the Pucará district had the highest mean concentrations of Zn (11.99 mg/kg) and Cu (5.27 mg/kg), and of As (0.30 mg/kg) and Co (0.24 mg/kg), respectively. The leaves of E. globulus and M. mollis plants from the Chupuro district contained the highest mean concentrations of Cr (0.98 mg/kg) and Pb (0.49 mg/kg), respectively. Regarding the assessment of risk to human health, the individual hazard quotients (HQ) and the cumulative hazard index (HI), which assess non-carcinogenic health risk, were below the safety threshold (HQ < 1 and HI < 1) for all plant species. The estimated total carcinogenic risk (TR), averaged over a 70-year lifetime, was found to be driven primarily by Cr and As, reaching a maximum of 1.14 × 10−6 ( E. globulus , Chupuro), the only value marginally above the precautionary reference target of 1 × 10−6. Overall, these results indicate a low level of potential risk, supporting the need for periodic monitoring to ensure the long-term safety of ethnobotanical plants rather than suggesting an immediate threat to human health.

Instituciones: Universidad Nacional del Centro del Perú; Universidad Nacional Autónoma Altoandina de Tarma