General Characteristics of Hospital Wastewater from Three Different Hospitals in Sri Lanka

Abstract

The hospital wastewater in Sri Lanka is a particular concern possibly due to the hazardous and toxic nature and its direct discharge into water bodies. Hence, this study focuses the characterization of wastewater generated from hospitals in Sri Lanka to assess the spatial and temporal variations. Wastewater samples were collected monthly from three different hospitals over a period of 3 months and they were tested for quality parameters: pH, temperature, electrical conductivity, total solids (TS), total dissolved solids (TDS), total suspended solids (TSS), volatile solids (VS), volatile suspended solids (VSS), biological oxygen demand (BOD5), chemical oxygen demand (COD), nitrate-N, phosphates and heavy metals. The results revealed that hospital wastewater exceeds the allowable limits of Sri Lankan wastewater discharge standards for many of the parameters. The maximum recorded values for TS, TDS, TSS, VS and VSS were 2658, 560, 314, 126 and 235 mg L-1, respectively. The demonstrated values for BOD5, COD were falling into a large range, 6-1950 and 130-1183 mg L-1. Nitrate-N and phosphate concentration varied and upper limit were reported as 3696 and 103.74 mg L-1. Apparently, maximum concentration of Cr(VI), Mn and Pb were reported as 0.23, 0.52 and 0.90 mg L-1. Further studies are undertaken to analyze volatile organic compounds (VOCs) and pharmaceuticals.