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Assessment of Non-carcinogenic Human Health Risk of some Heavy Metals in Land Snails commonly consumed in Bayelsa State, Nigeria

Author Affiliations

  • 1Department of Chemistry, School of Science, Isaac Jasper Boro College of Education, Sagbama, P.M.B. 74 Yenagoa, Bayelsa State, NIGERIA
  • 2 Department of Pure and Industrial Chemistry, University of Port Harcourt, P.M.B, 5323, Port Harcourt, NIGERIA

Res.J.chem.sci., Volume 5, Issue (10), Pages 61-66, October,18 (2015)


The body burden of Pb, Cu, Zn and Fe in two edible species of land snails (A. achatinaand L. flammea) obtained from the wild in Bayelsa State Nigeria and the non-carcinogenic health risk consequent upon the consumption of these snails was investigated in this study. The concentrations (mg/kg) on dry weight basis of the metals were determined using flame atomic absorption spectrometer, FAAS (GBC Avanta Ver 2.02 model) and found to be (― ± SD)Pb (29.5 ± 4.42), Cu (33.8 ± 6.25), Zn (75.3 ± 4.87) and Fe (2358.3 ± 35.67) for A. achatina and Pb (8.0 ± 082), Cu (23.7 ± 2.62), Zn (138.7 ± 4.49) and Fe (900 ± 303.56) for L. flammea. The target hazard quotients (THQs) and hazard index (HI) for evaluating the non-carcinogenic health risk was obtained from the individual and combined heavy metals due to dietary intake. THQ for the individual metals in A. achatina andL. flammea are in the decreasing order of Fe > Cu > Zn > Pb with risk value of 1.39, 0.34, 0.10, 0.00 and 0.53, 0.24, 0.19 and 0.00 respectively. Fe is the major contributor of the risk value which accounted for 55 - 75% of the THQs. The hazard index (HI) value obtained for A. achatina and L. flemmea were 1.83 and 0.96 respectively. The HI values indicates the presence of potential adverse health risk through the consumption of these two species of land snails. Therefore, moderate consumption of A. achatina and L. flemmea may be advisable considering the bio-accumulative nature of metals and to avoid human health risks to consumers in the future.


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