Publication:

LEVELS OF LEAD IN SOLVENT- BASED PAINTS FOR HOME USE IN MALAWI, LEVELS OF SELECTED HEAVY METALS IN MUDI RIVER WATER AND SEDIMENTS AND ENVIRONMENTAL IMPACTS OF MUDI RIVER SEDIMENTS

The presence of heavy metals in soils, water, and air, among others, has been reported by several researchers in Malawi in recent years. However, there is little documentation about their existence in sediments and paints. This study assessed lead levels in solvent-based paint for home use in Malawi, levels of selected heavy metals in Mudi River Water and Sediments and their Environmental and Ecological Impacts. Lead levels in paint ranged from below the detection limit (< 60 ppm) to 17,000 ppm, with an average of 2,561.04 ppm. 57% of the analysed paints contained lead concentration exceeding the new US and WHO limit of Pb in paint of 90 ppm, and 4% contained lead concentration greater than 10,000 ppm. The results also showed that lead content varied with the brand and colour of the paint. The research also found that, on average, the concentration of heavy metals in both sediments and water samples of Mudi River were below WHO, USEPA and MBS standards. On average, higher concentrations of heavy metals were detected during the dry season than in the wet season in both water and sediment samples. During the dry season, the average concentration of heavy metals in the surface water of Mud Rive was as follows: Fe = 2.08mg/l, Zn = 0.108mg/l, Cu = 0.015mg/l, Pb = 0.011 mg/l, and Cd = 0.005mg/l while the concentration of Cr was below the detection limit (˂ 0.006). During the wet season, the concentration of surface water of all the studied heavy metals was below the detection limit. During the wet season, on average, a high concentration of Fe (28mg/kg), followed by Zn (0.318 mg/kg), Pb (0.097 mg/kg) and Cu (0.030 mg/kg) were detected in the sediment’s samples. The potential ecological risk index (RI) indicated that the sediments posed low ecological environmental risk.