Frontiers of Agriculture and Food Technology

Frontiers of Agriculture and Food Technology ISSN 7295-2849 Vol. 10 (1), pp. 001-008, January, 2020. © International Scholars Journals

Full Length Research Paper

Heavy metals concentrations and burden in the bivalves (Anadara (Senilia) senilis, Crassostrea tulipa and Perna perna) from lagoons in Ghana: Model to describe mechanism of accumulation/excretion

Fred A. Otchere

Azimuth Consulting Group, 218 – 2902 West Broadway, Vancouver, British Columbia.V6K 2G8 Canada, E-mail: [email protected]; phone: 1.604.608.4283.

Accepted 09 November, 2019

Abstract

Seasonal sampling of the bivalves: Anadara (Senilia) senilis (n = 260), Crassostrea tulipa (n = 220), from two ‘open’ lagoons (Benya and Ningo) and a ‘closed’ lagoon (Sakumo), and Perna perna (n = 170), from rocky shores adjacent to Benya and Sakumo, were analyzed for their total Cu, Zn, Fe, Mn, Cd and Hg concentrations and total body burden (that is concentration multiply by total flesh weight) . Median concentrations for cockles were: 5, 38, 710, 10, 0.22 and 0.20 µg/g dw respectively. Cd and Hg levels in dry season samples were higher than those in wet season. While Zn and Fe dry season levels were lower than wet season with no variation in Cu and Mn. Median total body burden in cockles were: 3.3, 30.5, 370, 5.2, 0.28 and 0.13 µg respectively. Geographical variations observed were mostly due to size distribution rather than the ecological differences between stations. Log-transformed regression relationships between body burden and size were used to compare the species. Relationship between condition index, body burden and concentration were used to develop a model to describe mechanism of accumulation/excretion.

Key words: Heavy metals, bivalves, marine, lagoons, seasonal variation, accumulation, Ghana.