Response of some cyanobacterial species for adsorption of manganese, cobalt and nickel from untreated tannery effluent in Kano, Nigeria

Abstract

The research was conducted to monitor the performance of some endogenous species of Cyanobacteria for the adsorption of Manganese (Mn), Cobalt (Co) and Nickel (Ni) from untreated effluents of Fata Tanning Limited (FTL) in Kano between July 2014-June, 2015. Primary field investigation and laboratory analysis were the main sources of data in the study. The study areas were divided into three strata within which samples were collected using stratified sampling techniques from a depth of 0 30cm.The study assessed the adsorption capacity of some heavy metals namely; Mn., Co. and Ni using Atomic Absorbance Spectrophotometer (AAS). Indigenous cyanobacteria species identified and isolated were Anabaena variabilis, Lyngbya majusculata and Oscillatoria princeps using microscopy and standard phycological chart as described by Komerak and Anagnostidis, (1989). Bioremediation Bioassay was conducted to evaluate the adsorption capacity of the isolated organisms. The results showed that, tested organisms reduced the concentration level of heavy metals in the effluents to the standard limit proposed by FEPA (1997), WHO (1999) and (ICLARM, 1997). Anabaen was found to remove more Ni (4.13%) followed by Lyngbya (3.78%) all at 9 weeks after inoculation. Higher concentration of Mn (3.85%) and Co of (4.04%) were removed by Lyngbya and Oscillatoria at 9 weeks after inoculation. These findings indicated that all the tested organisms possessed great potential in removin heavy metals from untreated tannery effluents. These findings also showed that adsorption of heavy metals by the tested organisms increased with time from 3-9 weeks of inoculation and adsorption was significantly higher at 9 weeks after inoculation and some decline at 9 WAI.

Keywords: Cyanobacterial species, Effluent, FTL and Heavy metals