Human health risk assessment of heavy metals in energy drinks from the Tanzanian market

Abstract

Heavy metal contamination in the environment often originates from industrial discharges, packaging materials and manufacturing practices. This contamination can lead to the accumulation of toxic elements in food and beverages, including energy drinks, posing risks such as kidney dysfunction, neurological disorders and increased cancer incidence. This study assessed Cu, Cd, Ni, Cr, Zn, Fe, and Pb concentrations in ten energy drink samples from the Tanzanian market using atomic absorption spectrometry (AAS). Detected mean metal concentrations followed the order Cr < Ni < Cd < Cu, while Zn, Fe, and Pb were not detected. Cu, Ni and Cr levels were within WHO permissible limits, whereas Cd exceeded the 0.003 mg/L threshold in all samples, signaling significant contamination. Potential health risks were evaluated using Estimated Daily Intake (EDI), Hazard Quotient (HQ), Hazard Index (HI), and Incremental Lifetime Cancer Risk (ILCR). Mean EDIs for Cu and Ni were within FAO/WHO recommended limits, but Cd exceeded its Provisional Maximum Tolerable Daily Intake (PMTDI) value, with HQ and HI values above 1, indicating a notable non-carcinogenic risk. ILCR values for Cd (40.5E−04 to 67.5E−04) and some Ni values (2.5E−04 to 7.6E−04) exceeded the USEPA acceptable carcinogenic risk range (1E−06 to 1E−04), highlighting potential cancer risks from long-term consumption. These findings emphasize urgent public health concerns and the need for continuous monitoring, stricter regulatory control, and further research covering both local and imported energy drink brands to mitigate exposure risks.