Impact of Abattoir Wastewater Discharge on the Physicochemical Properties and Heavy Metal Levels of Dei-Dei Stream, Abuja, Nigeria

Abstract

This study aimed to determine the impact of abattoir wastewater discharge on the physicochemical properties and heavy metal levels of Dei-Dei Stream, Abuja, Nigeria. Water samples were randomly collected from the upstream and downstream sections of Dei-Dei Stream, while soil samples were collected from the farm behind the abattoir. Sampling was carried out at two-week intervals from March to April 2026. The physicochemical properties were determined using the American Public Health Association (APHA) standard methods and other standard analytical procedures. Wet digestion was performed on the water and soil samples, after which the samples were analyzed for heavy metals. The results of the physicochemical analysis showed that temperature, conductivity, turbidity, TS, TSS, TDS, pH, alkalinity, acidity, hardness, chloride, COD, and BOD were 27.87 ± 0.04 °C, 1395.78 ± 272.59 µS/cm, 12.59 ± 1.50 NTU, 888.41 ± 180.64 mg/L, 43.61 ± 6.72 mg/L, 844.8 ± 173.92 mg/L, 7.30 ± 0.06, 349.76 ± 39.11 mg/L, 23.5 ± 7.10 mg/L, 335.45 ± 52.95 mg/L, 2006.60 ± 286.56 mg/L, 104.66 ± 4.32 mg/L, and 72.2 ± 4.18 mg/L, respectively. The concentrations of the assessed heavy metals in the stream water ranged (mg/L) as follows: Fe (0.03–2.25), Zn (0.01–0.32), Pb (0.004–0.15), Cd (0.001–0.09), and Cu (0.001–0.99). The Enrichment Factor (EF), Geoaccumulation Index (Igeo), Contamination Factor (CF), and Pollution Load Index (PLI) consistently indicated that the farm soil was only slightly affected by heavy metal contamination. Overall, the findings revealed that abattoir wastewater discharge has impacted the physicochemical quality of Dei-Dei Stream, with elevated concentrations of some heavy metals, while the adjoining farm soil remained only slightly contaminated.