Heavy Metals and the Condition Factor of Farfantepenaeus notialis in a Tropical Brackish Water

Abstract

This study investigated the concentration of six metals in the cephalothorax and abdomen of Farfantepenaeus notialis in relation to its condition factor. The metal concentrations were determined using Atomic Absorption Spectrophotometer. The relationship between heavy metals and condition factor was determined through correlation and regression analyses while T test was used to compare the metal concentration in abdomen and cephalothorax. Allometric growth patterns were observed in the species, with K factors from 0.47 to 0.57. The bio-accumulation of metals was found to be in the following order: Zn>Fe>Mn>Cu>Pb>Cd. Cd, Pb, Cu, and Mn had higher concentrations in the abdomen, while Zn and Fe had higher concentrations in the cephalothorax. In addition, the Fe and Mn level was significantly higher than the Federal Environmental Protection Agency`s recommended limit. In both seasons, Pb in the abdomen was the only element that had a significant relationship with shrimp`s condition factor, but Manganese in the abdomen and Zinc in the cephalothorax had a significant relationship with shrimp condition factor in the wet season. Thus, the study area should be closely monitored in order to reduce the risks posed to the aquatic ecosystem and human population that relies on it for water and fish supplies.