Water quality evaluation from Lomé’s lagoon: Effects on heavy metals contamination on fishes.

The relevance of this study shows that in general, water of lake of lome has a strong alkalinity (ph raging from 8.8-9.2) and a strong salinity revealed by the high value of the electric conductivity (2800-3200 μs.cm-1). an impressive algae colony is composing the essential suspended matter (60-70 mg.l-1). the water turbidity was about 80-90 ntu. we also determined that in some places of the lake, the high concentration of nitrogen compounds appeared to be the major causing pollution since the ntk (total nitrogen) ranged from 20-22 mgn.l-1. in contrast, the cod (chemical oxygen demand) and the bod (biochemical oxygen demand) values were low (110 mgo2.l-1 and 40 mgo2.l-1 respectively). in the case of metallic elements, cadmium contents was very low in water, sediments and fishes. copper, lead, zinc and mercury concentrations in water were respectively 3.6; 8.0; 7.0 and 14.0μg.l-1. in fishes, the following measured values of the same elements were 5.0; 2.8; 20.2 and 5.5 μg.l-1 respectively.