Bioaccumulation of heavy metals in silver catfish (Chrysichthys nigrodigitatus) and tilapia fish (Oreochromis niloticus) from the brackish and freshwater in South-West, Nigeria

The Journal of Basic and Applied Zoology

Table 2 Maximum and Minimum Heavy Metals Concentration in Chrysichthys nigrodigitatus and Oreochromis niloticus

Heavy Metal	Max. mean (mg g⁻¹)	Fish spp. by location	Mini. mean (mg g⁻¹)	Fish spp. By location	Recommended limits in fish
Fe	2.02 ± 0.64	LLCN	0.34 ± 0.09	ONLL	146.00 mg (IAEA-407; Wyse et al., 2003)
Cr	0.08 ± 0.00	ARCN	0.05 ± 0.00	ARON	(0.020 mg/g) (WPCL, 2004)
Zn	9.56 ± 0.96	LLCN	3.93 ± 0.36	LLON	3.00 mg g⁻¹ (WHO, 2003)
Pb	0.27 ± 0.12	ARCN	0.1 ± 0.00	LLON	0.12 mg g⁻¹ (IAEA-407; Wyse et al., 2003)
Cu	0.89 ± 0.23	LLCN	0.30 ± 0.13	ARCN	3.28 mg g⁻¹ (IAEA-407; Wyse et al., 2003) 0.03 mg g⁻¹ (Khayazadeh and Abbasi, 2010)

LLCN (Lagos Lagoon Chrysichthys nigrodigitatus); ARCN (Asejire Reservoir Chrysichthys nigrodigitatus); LLON (Lagos Lagoon Oreochromis niloticus); ARON (Asejire Reservoir Oreochromis niloticus);