Skip to main content
Bulletin of the National Research Centre

Table 3 Seasonal variations of heavy metals concentrations (μg/g dry weight) in muscle tissue of Oreochromis niloticus

From: Seasonal assessment of some heavy metal pollution and Metallothionein gene expression in cultured Oreochromis niloticus

Heavy metal

Winter

Spring

Autumn

Summer

Cadmium

< 0.05

< 0.05

< 0.05

< 0.05

Copper

1 ± 0.02b

0.97 ± 0.05b

2.2 ± 0.1a

< 0.05

Lead

1.2 ± 0.08b

1.15 ± 0.8b

1.80.05a

< 0.05

Zinc

17.9 ± 0.6bc

21.4 ± 0.9b

50 ± 2a

10.7 ± 0.32c

  1. Data are shown as mean ± SEM; (n=5); mean values with unlike superscript letters were significantly different (p ≤ 0.05)
  2. FAO (1983) limits in fresh muscle (mg/kg): Cd (0.5), Cu (30), Pb (0.5), and Zn (30)
  3. EOS (1993) MPL limits in fish (mg/kg): Cd (0.5), Cu (20), Pb (2), and Zn (40)
Back to article page