Analysis of Heavy Metals Presence in Three Fish Species from Swali Market, Yenagoa, Bayelsa State

Heavy metal concentrations were assessed in three fish species: Citharinus citharus (Moon fish), Chrysichthys nigrodigitatus (Silver catfish), and Synodontis schall (Nile squeaker/Mandi), purchased from Swali Market in Yenagoa in August 2024. The samples were examined using Atomic Absorption Spectrophotometry (AAS). Zinc (0.923 µg/ml) and lead (0.027 µg/ml) were the most concentrated in C. citharus, while cadmium (Cd), chromium (Cr), arsenic (As), and nickel (Ni) were insignificant (p > 0.05). Zinc (3.503 µg/ml) and lead (0.010 µg/ml) were the most abundant elements in C. nigrodigitatus, with no measurable levels of Cd, Cr, As, or Ni. Zinc concentration in S. schall was highest at 4.225 µg/ml, while Pb and other elements were undetectable. Overall, Cd, Cr, As, and Ni levels were below the World Health Organisation (WHO) permissible limits. However, the presence of lead, a highly hazardous metal even at low levels, causes concern. These findings underline the importance of regular monitoring of fish sold at Swali Market in order to protect public health from hazardous metal exposure through diet.