ASSESSMENT OF HEAVY METAL CONTAMINATION STATUS IN BAKOLORI DAM SURFACE WATER USING POLLUTION INDICES.

ABSTRACT Heavy metal pollution indices used to rate aquatic systems, which are useful tools for determining the trace and heavy metal content of water, are the main culprits for an increased level of trace metals. Toxic metals are typically present in industrial, municipal, and urban runoff and can be harmful to human health and biotic life. Over the course of a year (November 2021 to October 2022) this study was conducted to explore and evaluate the pollution state of Bakolori Dam in Zamfara State. Water was drawn from each of the four study sites using 750 ml plastic bottles. Four stations were used for the study. For the sample analysis, the standard operating protocols of the WHO and UNEP were used. The findings indicate that there is a significant amount of iron (Fe), with global mean concentrations exceeding the WHO's 2022 upper limit. While being inside the acceptable standard include zinc, copper, and cadmium. The order of the trace heavy metals' total mean concentrations in mg/l was Fe (12.46 mg/l), Zn (0.39 mg/l), Cu (0.19 mg/l), and Cd (0.03 mg/l). According to the Monthly Pollution Index for the Dam, the Metal Pollution Index reached its maximum value in December (MPI= 199.17) and its lowest value in June (MPI=3.99). The Trace Metal Pollution Index (TPI) data indicated that April and June had the highest and lowest values obtained, respectively, at TPI=39.47 and TPI=0.35. In comparison to the wet season (18.54 and 6.54, respectively), the dry season had the highest MPI value (85.43) and the greatest TPI value (12.57). Therefore, it is essential to frequently examine the dam to make sure the water is suitable for drinking and agriculture..