Urbanizing with or without nature: pollution effects of human activities on water quality of major rivers that drain the Kumasi Metropolis of Ghana.

The effects of urbanization such as population upsurge, increased industrialization, urban agriculture, and rural-urban migration of persons exert pressure on the limited water resources in most cities. This study investigated the impact of human activities on the water and sediment quality of the three main rivers (Wiwi, Subin, and Suntre) in Kumasi, the second-largest city in Ghana. The physicochemical parameters and the concentrations of contaminants, including heavy metals, polycyclic aromatic hydrocarbons, pesticide residues, and microbial loads in the rivers, were linked to the specific human activities at the riverbanks. While all the 37 pesticide residues investigated in river sediments had concentrations below the detection limits (0.005 mg/kg for organochlorines, 0.010 mg/kg for organophosphates, and 0.010 mg/kg for synthetic pyrethroids), the study showed that the sediments are polluted with petrogenic and pyrogenic polycyclic aromatic hydrocarbons. River Subin, the most polluted among the three rivers, recorded benzo[e]pyrene concentrations up to 47,169 µg/kg. The geoaccumulation index and concentration factors show that the rivers are highly contaminated with metals such as cadmium, chromium, mercury, and arsenic and are related to human activities. The microbial quality of the rivers was poor, recording specific microbial loads of 6.8, 4.1, and 1.5 × 107 counts/100 mL respectively for Wiwi, Subin, and the Suntre Rivers. The three water bodies are therefore not suitable for recreational and irrigational purposes.

Solid waste management in informal urban neighbourhoods. Occupational safety and health practices among tricycle operators in Kumasi, Ghana.

The study examines the nature of activities and assess knowledge on occupational safety and health (OS&H) risks and practices among solid waste collectors in two low-income informal neighbourhoods in Kumasi (Aboabo and Asawase). Using observations and semi-structured interviews with 83 participants and relevant institutions, the findings indicate that informal tricycle waste collectors provided spot-to-spot waste collection using improvised sirens to signal their arrival. Workers generally had low knowledge, expressed less about occupational health risks, and thus adopted less safe work practices. The study however showed significant differences between knowledge of health risks (p < 0.000, R = 0.83) and years of working experience (p < 0.01, R = 0.74) and adoption of safe practices. Workers who had knowledge the associated health risks of the activity and also have been in the activity for more than 2 years were more likely to use at least one PPE/PPC. The study recommends that targeted interventions to mitigate risks and improve the health and safety of workers require effective risk communication. The study concludes that insight into OS&H is important to offer opportunities for better waste management strategies in the informal urban areas.

The policy implications of urban open space commercial vegetable farmers' willingness and ability to pay for reclaimed water for irrigation in Kumasi, Ghana.

The acute waste management problems, coupled with the proliferation of small scale industries in many developing countries, make low quality water treatment before use inevitable in the long run. These industries have the potential to discharge effluent containing chemicals and heavy metals into the environment. The indiscriminative use of pharmaceutical products by households in many of these countries is another source of health concern. Low quality water treatment in these countries has however been hampered by the high cost of infrastructure provision and maintenance. Cost-sharing among stakeholders appears to be a promising strategy to finance and maintain the wastewater treatment infrastructure. In this study therefore, the willingness and ability of urban open space commercial vegetable farmers to pay for reclaimed water for irrigation purposes has been assessed. One hundred open space commercial vegetable farmers and four vegetable farmers' associations were selected and interviewed in Kumasi in Ghana using semi-structured interview schedules and interview guides respectively. The results of the study show that approximately three out of every five vegetable farmers were willing to pay for reclaimed water for irrigation. The results further show that the probability of being willing to pay by farmers who agreed that the current water they used for irrigation was harmful is approximately 5.3 times greater than that of those who did not. The analysis of the farmers' ability to pay revealed that all the farmers would be capable of paying for reclaimed water at a price of US$0.11/m(3). This has implications for land tenure security and vegetable consumers' willingness to pay higher prices for the produce.