HISTOPATHOLOGY OF THE MUSCLE AND HEAVY METAL CONCENTRATIONS OF PERIOPHTHALMUS PAPILLO FROM ELECHI CREEK, PORT HARCOURT, NIGERIA

In polluted coastal areas mudskippers are the potential bioindicators and bio-accumulators of pollutants and may directly or indirectly be related with human health issues, especially as they are consumed as a local delicacy. The histopathology of the muscle and concentration of selected heavy metals (Pb, Cr, Cd, Ni and V) of Periophthalmus papillo, from Elechi Creek, Port Harcourt, Nigeria, were investigated for 12 months from May 2016 – April 2017. Samples of P. papillo were collected quarterly from five stations along the Elechi Creek. The stations were selected based on high industrial activity and effluent discharge. Five samples of fish were collected per station, quarterly and 2g of their muscle was used for histology and analysed to determine the heavy metal concentrations. Histological examination of the muscle samples was done and images captured with a Lecia DFC280 Digital Camera attached to a light microscope (Lecia 6000B). Data were analysed statistically to determine means, analysis of variance and mean separation using SPSS 2007. The following ranges and mean concentrations, respectively, were recorded for the metals under consideration: Cr 15.79-19.52mg/kg, 17.67±0.68mg/kg; Pb 4.37-16.48mg/kg, 9.73±2.45mg/kg; Cd 0.44-1.19mg/kg, 0.74±0.13mg/kg; Ni 2.18-7.77mg/kg, 4.68±1.06mg/kg, and V 0.11-0.37mg/kg, 0.30±0.12mg/kg. Concentrations higher than the permissible values were obtained for all the metals in all the stations. Histopathological micrographs showed severe organ degeneration in all samples. The concentrations of these metals were high and some exceeded international standards, especially for Cr, Pb and Cd. These concentrations may pose a health risk to consumers on one hand and to the mudskippers as their muscles are showing signs of degeneration. It is recommended that bio-monitoring of the sample stations should be conducted regularly and the public should be educated on the dangers of consuming fish harvested from the examined locations. Effluent discharge should also be regulated by the appropriate regulatory agencies