A. Y. Sangodoyin

Medical waste management in Ibadan, Nigeria: Obstacles and prospects

Quantification and characterization of medical waste generated in healthcare facilities (HCFs) in a developing African nation has been conducted to provide insights into existing waste collection and disposal approaches, so as to provide sustainable avenues for institutional policy improvement. The study, in Ibadan city, Nigeria, entailed a representative classification of nearly 400 healthcare facilities, from 11 local government areas (LGA) of Ibadan, into tertiary, secondary, primary, and diagnostic HCFs, of which, 52 HCFs were strategically selected. Primary data sources included field measurements, waste sampling and analysis and a questionnaire, while secondary information sources included public and private records from hospitals and government ministries. Results indicate secondary HCFs generate the greatest amounts of medical waste (mean of 10,238 kg/day per facility) followed by tertiary, primary and diagnostic HCFs, respectively. Characterised waste revealed that only approximately 3% was deemed infectious and highlights opportunities for composting, reuse and recycling. Furthermore, the management practices in most facilities expose patients, staff, waste handlers and the populace to unnecessary health risks. This study proffers recommendations to include (i) a need for sustained cooperation among all key actors (government, hospitals and waste managers) in implementing a safe and reliable medical waste management strategy, not only in legislation and policy formation but also particularly in its monitoring and enforcement and (ii) an obligation for each HCF to ensure a safe and hygienic system of medical waste handling, segregation, collection, storage, transportation, treatment and disposal, with minimal risk to handlers, public health and the environment.

Considerations on contamination of groundwater by waste disposal systems in Nigeria

Abstract The interdependence of water quality parameters with distance from polluting sources and depth of twenty four native wells in Abeokuta, Nigeria is examined in this study. In gross features, the bacteriological quality as monitored by coliform counts showed significant negative correlation of 0.74 and 0.60 with distance from polluting source and depth of well respectively. Most of the wells examined had construction defects and there was evidence of faecal contamination. The results highlight possible environmental impacts of lapses in construction and obvious contamination of this popular water systems. The study probably highlights the much needed awareness on the part of local residents and environmental health authorities to curb dangers inherent in poor sanitation and consumption of contaminated groundwater. The results could serve as a basis for planning and policy formulation on environmental sanitation, drainage systems, native well siting, construction, finishing and maintenance.

Characteristics and control of industrial effluent‐generated pollution

Evaluates existing systems of collection and disposal of industrial waste water in the Lagos metropolis, Nigeria. Examines the rate of generation of waste water in the paints, foods and beverages, battery, textile, brewery, and pulp and paper industries. These include among others some selected industries in Ikeja Industrial Estate, Lagos. The cases chosen are believed to give a broad outline of organic strength of industrial wastes as well as disposal problems. Results show biochemical oxygen demand, pH and temperature range of 44‐6000mg/l, 4.5‐9.5 and 30‐40°C respectively. Identifies problems facing industrialists in waste water treatment and disposal. Offers suggestions for minimizing environmental pollution by industrial effluents.

Hazardous wastes Assessing the efficacy of structures and approaches to management in Nigeria

In this study, characterization of hazardous wastes components, treatment and disposal systems were examined for Southwestern Nigeria. The data were used to assess the effectiveness of monitoring systems and existing regulations on the subject and to proffer solutions for efficient management. Three sources of hazardous wastes were examined, namely: household units, commercial enterprises and industrial outfits. The household units, which were further classified into high, medium and low income earner groups, produced wastes with hazardous components of 5.6 per cent, 4.4 per cent and 4.2 per cent respectively. Typical results also show that the Pb component of wastes from a hairdressing salon, and that from a local aluminium pot making industry, were 0.026ppm and 0.046ppm respectively. Most of the other parameters examined were far higher than limits recommended by the World Health Organisation (WHO) for safe disposal. The trace elements, however, fall within the recommended limit of WHO. The current investigation has stressed the need to: properly monitor industrial wastes discharge as well as environmental protection officials to conduct the test themselves; enforce regulations that might require the installation of treatment plants appropriate for the type of wastes generated; encourage waste reuse and recycling; intensify public education; remediate land already polluted by hazardous waste; divert some profit generated by industries to waste management research; and establish standard laboratories all over the study area for unhindered waste monitoring.

Rainwater chemistry as influenced by atmospheric deposition of pollutants in Southern Nigeria

Examines rainwater chemistry as it relates to atmospheric pollution in Southern Nigeria. Rainwater samples were collected and analysed for major cations and anions in Lagos, Ibadan and Port Harcourt, these sites reflecting industrial, residential and oil flaring regions respectively. In general, water samples from Ibadan were about neutral. Correlation studies revealed that HCl and H2SO4 dominated the slightly acidic rainwater in the Lagos and Port Harcourt areas respectively. The effect of marine spray from the Gulf of Benin was observed with trace of NaCl. The reaction of the much emitted NH3 with the available SO42– in the atmosphere produced (NH4)2SO4 which acted as a neutralizer for samples from the Lagos area. The findings suggest that rainwater from most industrial cities of Nigeria are tending towards acidity and if oil flaring activities are not checked, there is a tendency of increasing acidic rainwater in the delta regions. The observation and findings are useful for preliminary assessments of the influence of rapid industrial and urban development on atmospheric pollution and indirectly rainwater constituents.

Nutrient benefits and environmental aspects of land disposal of livestock waste

Examines the relative nutrient status and public health aspects of six livestock manures when added to soil. Provides analysis of the chemical composition of soils at pig, cattle, goat, rabbit, sheep and poultry waste dump sites and shows a highly significant difference in the level of added nutrients. Draws the conclusion that the observed levels of micronutrients at all waste sites suggest that potential plant toxicity and food chain accumulation problems will be low. Highlights the effect of land application of the manure on human health.

Subsurface water quality and quantity from the standpoint of irrigation and livestock

Field studies were undertaken at the Oyo North Agricultural Development Project (ONADEP), Shaki, Nigeria in 1988 and 1989 to evaluate the reliability and quality of subsurface water sources in relation to irrigation and livestock usage. Based on data from 22 water samples, 15 soil types, seasonal consumption of water for 10 major crops and extensive hydrogeological records, it was established that (i) alkalinity and salinity hazards are low, hence the groundwater of the study area is suitable for irrigation, (ii) excessive boron levels might restrict the usage of the groundwater of the study area for livestock, (iii) subsurface water sources, estimated at about 31,000 ML per annum is capable of satisfying only 12% of agricultural and livestock water demand of the study area, and (iv) the area under consideration is not endowed with abundant surface and subsurface water as shown by previous studies.

Women's role in rural water supply and development: Trends and expectations in Nigeria

SummaryThere has been a paucity of reliable data on the contribution of Nigerian women in rural development, particularly with respect to water projects. From a detailed survey of many rural settings, and an evaluation of the availability of sources of water and the existing methods of purification, it was discovered that rural women, especially those of younger years, were heavily involved in water collection. The time and energy involved in water fetching and purification could sometimes be so high that other economic and domestic activities were adversely affected. The participation of Nigerian women in water development and quality improvement is hindered by problems, such as their standard of education, low level of awareness of the benefits of a good water source, lack of funds and organisational constraints. In general, this study has recognised an urgent need for more imaginative, better funded and better co-ordinated water development projects for the enhancement of the quality of life, especially for women in rural settings.

Wastewater Applications: Changes in Soil Properties, Livestock Response and Crop Yield

Examines the potential for excessive crop uptake of nutrients, soil mineralization, and response of livestock to the usage of Ogunpa Stream, Ibadan, Nigeria. A number of surface water and soil samples were collected from the Ogunpa and small irrigated farms near the stream for physico‐chemical examination. Results show that the stream is suitable for irrigated agriculture but not for aquaculture and livestock breeding especially in the middle reaches. The added nutrients accumulated in the cultivated layer of the soil. There was some evidence of migration of some elements down from the cultivated layer. The potential hazard for pollution caused by irrigating with the polluted water threatens crop and vegetables grown on adjacent farms as well as groundwater of the nearby area. This may seriously affect the consumers. It is recommended that residents around the stream become aware of how to reduce the pollution level.

Assessment of the adequacy of a water treatment process by in‐plant monitoring

The paper describes the results of a short‐term study on the performance of the Ogun State Water Treatment Plant, Nigeria, maintenance procedures and problems as well as challenges facing management of water agencies in the face of reduced government funding. Physical and chemical tests of raw water reveal a minor impact on water quality from agricultural, municipal and industrial activity. The conventional units used so far produced treated water which compared favourably with standards. However, taste, odour, heavy metals, pesticide residues and bacteriological data are not available for comparison. The performance of treatment units fluctuated widely during the test period. The efficiencies of aerators, coagulation, sedimentation and rapid sand filtration averaged 58%, 25%, 77% and 23%, respectively in the reduction of chemical oxygen demand, turbidity, suspended solids, and dissolved solids. Suggestions offered to meet the challenge of provision of adequate, safe and wholesome water to the teeming pop...