Physicochemical Characterization of Mining Waste from the Betare-Oya Gold Area (East Cameroon) and an Adsorption Test by Sabga Smectite (North-West Cameroon)

Table 2

Relative concentration of the heavy metals analyzed.

Parameters	Unit	Concentrations			WHO standards
		Min	Med	Max
Cu	mg·L^−1	0	0.005	0.01	2
Zn	mg·L^−1	0	0.015	0.03	3
Ni	mg·L^−1	0	0	0	0.02
Mn	mg·L^−1	0.04	0.12	0.2	0.05
Fe	mg·L^−1	0.4	2.15	3.9	0.3
Cr	mg·L^−1	0.02	0.02	0.02	0.05
As	mg·L^−1	0.005	0.015	0.025	0.01
Pb	mg·L^−1	0.012	0.018	0.024	0.01