The present study assessed potentially toxic elements (PTEs) and microbial contamination in soil and groundwater around a municipal solid waste dumpsite in Zomba, Malawi. The potential ecological and health risks to communities were also examined. The results revealed that wet season groundwater had elevated total coliforms (20,900 CFU/100 mL), Escherichia coli (3300 CFU/100 mL), Staphylococcus aureus (2500 CFU/100 mL), and Vibrio cholerae (5900 CFU/100 mL), which were significantly higher than the permissible limits of the Malawi Standards. In water samples, PTEs, particularly cadmium (Cd; 0.011–0.08 mg/L) and chromium (Cr; 0.02–0.41 mg/L), were detected at concentrations of concern. In the soil samples, lead (Pb) concentrations ranged from 0.16 to 224.05 mg/kg, copper (Cu) concentrations ranged from 3.03 to 94.86 mg/kg, Cd concentrations varied between the BDL and 0.89 mg/kg, arsenic (As) ranged from BDL to 1.88 mg/kg, and the Cr varied between 0.07 and 0.91 mg/kg. Furthermore, the cancer risk (CR) assessment indicated that all sampling points had CR levels greater than 1 × 10⁻³ for adults, with 40% of the sampling points showing elevated CR levels for infants and children, highlighting the cancer risk from Cd exposure, especially among vulnerable populations.

The present study evaluated heavy metal and microbial contamination in soil and groundwater around a municipal solid waste dumpsite in Zomba, Malawi. It also examined the potential ecological and health risks to local communities. Samples were analyzed for heavy metals using an atomic absorption spectrophotometer (AAS) and for microbes using standard methods from the United States Environmental Protection Agency. Results showed that groundwater during the wet season had elevated levels of total coliforms (20900 cfu/100 mL), Escherichia coli (3,300 cfu/100 mL), Staphylococcus aureus (2,500 cfu/100 mL), and Vibrio cholerae (5,900 cfu/100 mL), all significantly above the permissible limits set by Malawi Standards (MS). Heavy metals such as Cr (0.011–0.14 mg/L) and Cd (07 – 041 mg/L) were also detected, raising concerns. In soil samples, lead (Pb) ranged from 0.16 to 224.05 mg/kg, copper (Cu) from 3.03 to 94.86 mg/kg, cadmium (Cd) from below detection limit (BDL) to 0.89 mg/kg, arsenic (As) from BDL to 1.88 mg/kg, and chromium (Cr) from 0.07 to 0.91 mg/kg. The cancer risk assessment showed all sampling points had CR levels exceeding 1 × 10^-3 for adults, with 40% of points indicating elevated CR levels for infants and children, emphasizing the cancer risk from Cd exposure, especially among vulnerable groups. These findings call for urgent intervention by the Ministry of Water Resources and Sanitation's groundwater division, in partnership with Zomba City Council, to provide safe water alternatives for nearby communities.

The present study assessed heavy metal and microbial contamination in soil and groundwater surrounding a municipal solid waste dumpsite in Zomba, Malawi, and in-vestigated the potential ecological and health risks to nearby communities. During the wet season, groundwater samples showed elevated counts of total coliform (20900 cfu/100 mL), Escherichia coli (3300 cfu/100 mL), Staphylococcus aureus (2500 cfu/100 mL), and Vibrio cholerae (5900 cfu/100 mL), all exceeding Malawi Standards limits. Water samples also contained concerning concentrations of chromium (0.011–0.14 mg/L) and Cadmium (0. 07 – 041 mg/L). In soil, lead ranged from 0.16 to 224.05 mg/kg, copper from 3.03 to 94.86 mg/kg, cadmium from below detectable limit to 0.89 mg/kg, arsenic from below detectable limit to 1.88 mg/kg, and chromium from 0.07 to 0.91 mg/kg. Cancer risk assessment showed exceeded the acceptable CR threshold of 1 × 10-3 for adults, while 40% exceeded this threshold for infants and children, indicating a notable cancer risk, particularly from cadmium exposure.