Assessment of Levels, Speciation, and Toxicity of Trace Metal Contaminants in Selected Shallow Groundwater Sources, Surface Runoff, Wastewater, and Surface Water from Designated Streams in Lake Victoria Basin, Uganda

Table 13

The Swedish Environmental Protection Agency (Naturvårdsverket) criteria.

Metal (µg/l)	Class 1 (very low)	Class 2 (low)	Class 3 (moderate)	Class 4 (high)	Class 5 (very high)
Cd	<0.01	0.01–0.1	0.1–0.3	0.3–1.5	>1.5
Cu	<0.5	0.5–3	3–9	9–45	>45
Ni	<0.7	0.7–15	15–45	45–225	>225
Pb	<0.2	0.2–1	1–3	3–15	>15
Zn	<5	5–20	20–60	60–300	>300