Community Awareness and Health Risk of Heavy Metals Through Consumption of Sardine ( <i>Rastrineobola argentea</i> ) From Lake Victoria, Tanzania

Sardine (<i>Rastrineobola argentea</i>) is a crucial food source for East African communities around Lake Victoria, providing essential nutrients such as protein, amino acids, minerals, and vitamins. However, heavy metal contamination in aquatic environments threatens its safety and may affect human health. This study assessed community awareness of heavy metal contamination and estimated the health risks from sardine consumption in Lake Victoria, Tanzania. A cross-sectional study was conducted in Mwanza, Kagera, and Mara regions. A semi-structured questionnaire assessed awareness and consumption, while a Flame Atomic Absorption Spectrometer quantified cadmium and lead concentrations in sardine samples. About 80% of 425 participants were women, and the majority (96.2%) were unaware of heavy metal contamination. Median concentrations in sardines were 0.081 ± 0.057 mg/kg (cadmium) and 0.012 ± 0.005 mg/kg (lead). Estimated daily intakes in mg/kg/day were cadmium (1.043-1.175 × 10^-5) and lead (2.704-3.047 × 10^-5). The target hazard quotients were 0.014 (cadmium) and 0.024 (lead), with hazard indices ranging from 0.0053 to 0.0060. Target cancer risk values ranged from 1.03 × 10^-9 to 1.70 × 10^-5. Heavy metal levels in sardines and daily exposure were within permissible limits set by national and international standards. Target hazard quotients, hazard indices, and cancer risk values were all below tolerable limits, indicating no significant health risks from consuming sardines from Lake Victoria. These findings suggest that although community awareness of the risk of heavy metal remains low, the concentrations of cadmium and lead in sardines and the associated dietary exposure do not pose significant health risks to consumers. The study recommends continuous monitoring, awareness campaigns targeting stakeholders, and promoting raised racks for drying to reduce contamination. These findings offer preliminary evidence to inform decisions by environmental, food, and fish authorities, local governments, and fishing communities, and raise awareness among traders and consumers.