Table 5.

Geoaccumulation Index (I_geo) values are indicted below for selected element concentrations in the sediment from the four zones sampled in Winam Gulf and Lake Victoria

	Ag	Al	As	Cd	Cr	Cu	Fe	Hg	Mg	Mn	Ni	Pb	Sn	Th	Ti	U
Igeo	0.07	80,000	13	0.3	90	45	47,200	0.4	15,000	850	68	20	6	12	4600	3.7
North	1.28	− 0.51	− 2.49	− 0.80	− 1.11	− 0.43	− 0.15	− 3.61	− 1.52	− 0.05	− 1.55	− 0.35	− 1.00	0.14	0.12	− 0.74
South	1.22	− 0.62	− 1.79	− 0.51	− 1.11	− 0.79	0.27	− 4.39	− 1.57	1.25	− 1.36	0.18	− 0.91	1.06	0.09	− 0.09
Straits	1.10	− 0.72	− 2.81	− 0.87	− 0.61	0.12	0.24	− 3.91	− 0.54	0.82	− 1.39	− 0.56	− 1.23	− 0.06	0.75	− 1.06
Lake	0.93	− 0.95	− 2.45	− 1.18	− 0.92	− 0.04	0.16	− 3.18	− 0.91	0.11	− 1.60	− 0.82	− 1.45	− 0.22	0.54	− 1.01

Values are in mg kg⁻¹. Values are determined from the International geochemical background shale values as defined in Table 1