From: Bamidele Fashube, Abuja
THE National Oil Spills Detection and Response Agency (NOSDRA), has attributed the death of croakier fishes washed ashore the Atlantic Ocean, in the Niger-Delta to toxic discharges into the ocean.
Recently, some dead fishes were washed ashore the ocean bank in Delta, Rivers and Bayelsa states a development which led to the launch of an investigation by the regulatory agency into probable cause.
Some environmentalists in the country also raised alarm over the incident and called for an immediate probe.
In a statement issued on Thursday, the agency’s Director-General, Idris Musa, said findings revealed that the fishes had died as a result of toxic wastes channelled into the ocean.
He explained that the toxicity found in the dead fishes and water samples was caused by pollution from heavy metals emanating from industrial and domestic wastes.
Musa stated that the heavy metals present in the study include Cadmium, Chromium Copper, Zinc and Iron that exceeded regulatory standard limits in the coastlines of the three states, Delta, Bayelsa and Rivers.
While explaining how these toxic substances get into the ocean, he said:”most industrial and domestic wastes which contain heavy metals such as cadmium, iron, zinc, copper found their ways into drainages and onward transfer to the water bodies.
“Their deleterious impact may be negative to aquatic species, other mammals and human beings. The main sources of these are batteries, galvanised pipes, fertilisers, sewage sludge and plastics. Such may be the case in the analyses of dead fishes found at the coastline in Delta and Bayelsa where chromium was found in fish tissue.
“Copper was also found in the fish tissue sampled in Delta State but not in those of Bayelsa and Rivers State. Furthermore, a sudden release of heavy metals is not likely to kill fishes except those trapped at the point of release because, cadmium in particular is highly toxic.
The DG further explained that:“Long term accumulation (chronic) rather than short term (acute) heavy metals,” could cause the death of fishes.
However, he noted that the deaths were not linked to oil leakages as the levels of hydrocarbon in the samples tested were within regulatory limits.
“The results of the laboratory tests were perused, and we make explanation on the parameters of concerns that were analysed for the purpose of clarity and understanding. As earlier mentioned, the findings did not show hydrocarbons (Oil) as the possible cause of the death of the fishes,”he said.
He further disclosed that relevant government agencies with mandates on the marine environment collaborated with NOSDRA to undertake the study.
According to him, the agencies involved in the study are:Nigerian Maritime Administration and Safety Agency (NIMASA), Nigerian Institute of Oceanography and Marine Research (NIOMR), National Environmental Standards and Regulations Enforcement Agency (NESREA).
He said the Federal Institute for Fisheries Research was also among the establishments enlisted in the efforts to unravel the likely causes of the massive death of the fishes.