COMPARATIVE STUDY OF PHYSICOCHEMICAL PARAMETERS OF WASTEWATERS FROM HOSPITALS, DOMESTIC AND AGRICULTURAL SITES IN KANO METROPOLIS

Abstract

Wastewater pollution is a major environmental and public health concern, particularly in rapidly urbanizing
regions. This study assessed the physicochemical parameters of wastewater in Kano Metropolis, Nigeria,
across the dry and wet seasons to evaluate its quality and potential environmental impact. Wastewater samples
were collected from three sites which are hospital discharge points, domestic drainage systems, and
agricultural sites. A six-month sampling campaign was conducted across selected hospital, domestic, and
agricultural wastewater sites in Kano Metropolis, Nigeria, yielding a total of 72 wastewater samples. The
samples were analyzed for key physicochemical parameters, including pH, temperature, turbidity, electrical
conductivity (EC), total dissolved solids (TDS), dissolved oxygen (DO), and biochemical oxygen demand
(BOD), using the analytical procedures described in the study methodology. Descriptive statistics were
employed to characterize parameter distributions, while paired-samples t-tests were used to evaluate seasonal
differences. Correlation analysis was further applied to assess associations among the measured
physicochemical parameters. The results revealed seasonal variations in wastewater quality, with higher
contamination levels observed during the dry season due to less water flow and reduced dilution effects. All
effluents had temperatures within acceptable limits with an overall mean of 28.2°c, suggesting minimal
thermal impact on receiving water bodies. The pH values of all sources were within permissible ranges (6.5),
although slight acidity was observed in some hospital and agricultural samples. Dissolved oxygen levels were
below acceptable standards across all sites with mean value of 3.7 mg/l, indicating poor water quality. The
Biological oxygen demand values were low across all sources (1.92 mg/l), suggesting moderate levels of
biodegradable organic matter. Also, turbidity mean (14.59 NTU) exceeded WHO guidelines in hospital and
domestic sources, highlighting the presence of suspended solids and potential microbial contamination. The
findings revealed significant pollution of wastewater in Kano Metropolis, posing risks to environmental and
public health. There by recommends the need for decentralized wastewater treatment systems, especially at
hospitals and urban households, and regular monitoring to safeguard public and environmental health.