Nigeria is the most populous country in Africa with a population of over 180 million people. The country is endowed with generous resources of water bodies, the span of water bodies within the country is estimated to be 900 km2.This water provides resources for fishery, transportation, irrigation, recreation, commercial and domestic uses.
Kano is one of Nigeria’s major economic cities, with Challawa industrial estate being the location of many industries. This area suffers discharged waste in the form of effluents into River Challawa, which is the main source of irrigation water for agriculture and sometimes for human and animal consumption.
It is estimated that 75% of the world population, mostly in developing countries, does not have access to safe drinking water. Among the most pressing environmental problems facing developing countries include air, water and soil degradation. Of these, water pollution poses a serious challenge due to its impact on large economics activities.
The problem of industrial effluent pollution requires attention especially in the case of Challawa industrial estate, Kano Nigeria. Industrial survey analysis confirmed that 60 industries discharged untreated effluents into the river and only 6 surveyed industries (10%) had primary treatment plants ranging from oxidation tanks to sedimentation tanks in Challawa industrial area. Also water analysis showed excess amounts of heavy metals such as mercury, lead, chromium, and iron .
Studies proved that some selected effluents from industries in Ikeja, Lagos and Challawa, Kano Nigeria, were analyzed and it was reported that the concentration of effluent discharged is on the high side, exceeding the maximum recommended unit. Furthermore, the characteristics, as well as the pollution implications of effluents from tannery industries in Kano metropolis, Kano State Nigeria were analyzed and it was discovered that effluent quality discharged by the tanneries differed significantly above the limits set by Nigerian Industrial Standard and World Health Organization.
In general, less than 10% of industries in Nigeria treat the affluent before being discharged into the river. Different regulations put in place to protect the marine environment and other water bodies in Nigeria have not been effective in controlling the indiscriminate dumping of effluent into open water bodies.
The major causes of effluent discharge into Challawa and other affected cities in Nigeria could be narrowed down to lack of policies to control pollution, unplanned industrial growth, use of outdated technologies, inefficient waste disposal, leaching of resources from our natural world and natural resource usage.
The release of untreated effluent affects the natural water bodies, flora and fauna of the ecosystem and increases the effect on human health and environment. Pollution of water with heavy metals is of grave consequence because both terrestrial and aquatic lives may be poisoned. It may cause diseases due to the presence of some hazardous substance which may distort the water quality, add odours, and significantly hinder economic activities. Particulate concentrations of some selected heavy metals in surface water of river Challawa in attempts to established both long- and short-term concentrations effects on health of human and animals are typhoid fever, skin irritation, cholera, pulmonary edema, disruption of endocrine system, birth defects (spina bifida, cleft lip, heart defect e.t.c).
The socio-economic status of the Challawa community area is highly poor and most of the population are laborers in factories, and have low incomes that cannot enable them to satisfy their basic needs. They have a low level of education, and therefore may not have adequate awareness of the effects of pollution to their health. The majority of the population are suffering from respiratory diseases especially after their residence in the area, or due to their working in factories that released substances such as dust and gases irrespective of any precautions taken (e.g. textile, chemical, and ternary factories). Skin irritations due to direct contact with chemicals or using the empty containers from factories waste or sometimes transmitted by insects that breed due to the poor sanitary system in the area is also of concern. Ingestion diseases are prevailing especially among children, because their soil is contaminated with different types of wastes. Children play and sometimes eat polluted soil particles, which might subject them to ingestion diseases. In addition to this, there were trace cases of cancer and mental or psychological diseases in the community.
In the agricultural fields, the main problem is the loss of crops because waste covers the farms and prevents air and sun from filtering and impedes their health and safe crop growth. Another problem found is related to irrigation channels that were blocked up by accumulating waste. Sometimes waste or dust released from loaders, while passing through narrow roads of the farms towards dumping sites, also cause damages to the small vegetable fields near the roads.
It is recommended that among the major ways to tackle water pollution and other types of pollution in Challawa, is there should be awareness about waste hazards through concerned civil societies. Strict legislation and enforcement to implementation of laws. Periodically conduct environmental impact assessment (EIA). Involve the target groups and affected community members (eg Challawa community) in awareness programmes and encourage their participation in non-governmental-community based organizations. Improve waste management which should involve the reduction, re-use, and recycle of waste in order to secure natural resources. Improve and enforce Environmental Impact assessment (EIA) among polluters and decision makers in order to reduce hazardous waste effects on natural resources. There should be a plan to relocate the residential areas far from industrial areas and remove the dumping sites to more spacey non-productive lands.
In Nigeria, most of the portable water used for domestic, agricultural and industrial purposes is channeled from rivers and groundwater. The quality of these water bodies cannot be guaranteed due to constant disposal of industrial effluents, agricultural pesticides, petroleum activities and human activities.
Presently, very little if anything has been done at integrated level concerning industrial pollution abatement in Challawa waters and community. Moreover, there is very little or no institutional memory in Nigeria on the influence of industrial waste on human health, thus, a detailed campaign should be put in place, elucidating the mechanism of water pollution especially with regard to these toxic sources and substances of pollution.
Government should, as a matter of urgency, adopt legal, administrative and technical measures to eliminate or lessen the undesirable effects of industrial effluents in Nigerian water bodies. Imposition of direct charges on industrial effluents by the regulating agency, as well as continuous monitoring and surveillance is imperative in order to ensure the protection of Nigerian water resources from further degradation as a result of pollution.
Dr. Adamu Abubakar Sadeeq, FASLN
Ahmadu Bello University, Nigeria.