Environmental Impacts Related to the Activities of the Medical Waste Incinerator at a Hospital in Abobo (Abidjan, Ivory Coast)

Abstract

The aim of this study was to assess the environmental impacts associated with the activities of an incinerator installed in a hospital in Abobo. The study involved weighing medical waste, measuring the quantities of gases released into the environment, and collecting and weighing the ash obtained after incineration. The collected ash represented 24% of the total mass of incinerated waste. Incineration reduced the mass of medical waste by 76%. The wastewater used to scrub the incinerator fumes was highly acidic (pH = 2.52) and therefore fell outside the discharge limits (5.5 ≤ pH ≤ 8.5) set by the Ivorian standard. In addition, the assessment of air-pollutant concentrations showed mean values of 223 ± 17 ppm, 4354 ± 123 ppm, 0.17 ± 0.04 ppm, and 0.24 ± 0.12 ppm for CO, CO2, NO2, and SO2, respectively. These values exceeded the limits cited from the USEPA (2022) and WHO (2025) guidelines: 10 ppm for CO, 500 ppm for CO2, and 0.04–0.06 ppm for NO2 and SO2. Similarly, the concentrations of Cr (112 ± 25 mg/kg), Cu (96 ± 17 mg/kg), Pb (53 ± 11 mg/kg), Ni (35 ± 09 mg/kg), and Zn (247 ± 29 mg/kg) in the ash were higher than the corresponding upper continental crust (UCC) background concentrations of 35, 14.3, 17, 18.6, and 52 mg/kg. However, the study was conducted using a single incinerator, which may limit the generalisability of the findings to settings with different sociopolitical and economic conditions. In addition, toxic gases were released into the environment without prior treatment. Therefore, medical waste and incineration residues should be disposed of appropriately to minimise environmental contamination and potential public-health risks.