Lead and Cadmium Levels in Water, Surficial Sediments, and Edible Biota of Urban Rivers in Dar es Salaam, Tanzania, During Two Seasons

This study evaluated levels and seasonal patterns of lead (Pb) cadmium (Cd) in sediment, water, mudskippers (Periophthalmus argentilineatus) from urban rivers Dar es Salaam, Tanzania. The samples were seasonally collected 15 locations, treated as appropriate, analyzed instrumentally. intended to establish contamination levels, identify hotspots, assess ecological human health risks. results indicated that Cd concentrations lower than Pb all the sample matrices. In water samples, (0.7 24.0 mg/L, n = 30, mean 7.2 ± 6.5) higher both World Health Organization (WHO) Tanzanian Bureau Standards limits, whereas was below detection limit. sediment (9.0 159.3 mg/kg, 44.7 36.6) (0.03 0.82 0.24 0.14) exceeded quality guidelines for protection aquatic life. mudskipper contained Food Agriculture (FAO) WHO maximum permissible limits. they safe consumption. Metal sediments during dry season wet season, probably owing contaminated runoff land-use practices showed opposite pattern. Determination potential index (PCI) enabled identification two hotspots may need intervention. Evaluation chronic daily intake (CDI), hazard quotient (HQ), (HI) implied minimal Contamination by these toxic metals, be it low concentrations, is an issue concern.