Assessment of Potentially Toxic Elements in Tea Beverages Prepared by Vendors Within Bayero University kano Old Campus: Implications for Public Health

Tea is one of the most widely consumed beverages worldwide, making contamination by potentially toxic metals a public health concern. This study determined the concentrations of arsenic (As), cadmium (CD), chromium (Cr), nickel (Ni), and lead (Pb) in five commercially available tea brands sold around Bayero University Kano (BUK) Old Campus, Nigeria, and assessed their transfer into tea infusions and associated health risks. Maximum concentrations in dry tea were 0.72 mg/kg (As), 0.21 mg/kg (Cd), 3.88 mg/kg (Cr), 3.84 mg/kg (Ni), and 3.85 mg/kg (Pb), while maximum concentrations in tea infusions were 0.024, 0.00080, 0.044, 0.05180, and 0.01060 mg/L, respectively. Transfer rates ranged from 14.0–27.8% (As), 14.0–19.0% (Cd), 35.2–64.2% (Cr), 28.1–67.5% (Ni), and 11.9–13.8% (Pb). Significant differences in mean metal concentrations were observed (p < 0.05), and Pearson correlation analysis revealed strong positive associations among Cr, Ni, and Cd, indicating possible common sources or similar accumulation behavior. Estimated daily intakes were below their ‎respective oral reference doses, while hazard quotients and hazard indices (4.56 × 10⁻²–2.68 × 10⁻¹) remained below 1, indicating negligible ‎non-carcinogenic risk. However, total cancer risks (3.39 × 10⁻⁵–7.45 × 10⁻⁴) exceeded acceptable lifetime limits for some tea brands, suggesting a potential carcinogenic risk from long-term consumption‎.