Evaluation of the Efficiency of Hospital Wastewater Treatment Systems and Stations in the Atlantic and Littoral Departments of Benin

Healthcare institutions are responsible for the pollution of ecosystems through their activities. The waste water produced by the various departments of these facilities is piped to treatment plants where it must be treated to meet standards for discharge into the environment. In order to assess the efficiency of the wastewater treatment plants and treatment systems of large hospitals in the departments of Atlantic (the most populous department in Benin) and Littoral (the economic capital) in the south of Benin, samples were taken upstream and downstream of the treatment plants and systems installed in these centres. Physico-chemical parameters such as temperature, pH, total suspended solids and TDS were measured "in situ" using an AQUAREAD multimeter. The other pollution parameters (COD, BOD5, TN, total phosphorus) were determined in the laboratory according to French standards. The results obtained show that the treatment plants of the University Hospital of Mother and Child (CHU-MEL) and the Allada Zone Hospital (CHZ Allada) are effective, with high reduction rates of 43%. 100% for suspended solids, 60 to 100% for TSS, 100% for total phosphorus and COD and 97% for BOD5. The laundry treatment systems of the CHU-MEL and the St Luc Hospital in Cotonou are less effective with reduction rates of 2 to 13% for TSS, 7 to 35% for BOD5, 5% for COD, 0 to 16% for TSS and 5 to 9% for total phosphorus. At the microbiological and parasitological levels, almost all samples taken and analysed after treatment are free of microorganisms and parasites. In view of the danger that this type of waste poses to the environment, and in view of the reduction rates and the values of the physico-chemical parameters of the effluents obtained in this study, it is urgent to promote the installation of treatment stations for this type of waste in the centres that do not yet have them, while ensuring the maintenance and proper functioning of the existing ones.