Trace metal Month Viscera Shell
V August 1.98 ± 0.43 1.52 ± 0.73
  September 2.05 ± 0.99 1.57 ± 0.98
  October 1.86 ± 0.54 0.87 ± 0.19
Mn August 20.64 ± 2.13 1.03 ± 0.35
  September 10.60 ± 0.35 2.66 ± 1.08
  October 12.22 ± 3.98 1.06 ± 0.55
Fe August 824.49 ± 3.55 98.14 ± 5.90
  September 685.43 ± 15.32 175.56 ± 7.86
  October 240.36 ± 43.12 77.64 ± 8.65
Co August 3.52 ± 1.21 1.22 ± 0.84
  September 1.99 ± 0.57 1.31 ± 0.43
  October 1.80 ± 0.69 0.40 ± 0.62
Ni August 30.23 ± 4.43 10.49 ± 2.93
  September 34.50 ± 6.12 12.64 ± 0.54
  October 23.34 ± 4.28 9.18 ± 1.17
Cu August 168.32 ± 5.66 75.78 ± 5.86
  September 126.65 ± 8.29 83.93 ± 21.42
  October 146.90 ± 6.42 63.43 ± 9.64
Zn August 1.48 ± 0.84 0.89 ± 0.23
  September 2.32 ± 0.75 2.10 ± 0.28
  October 2.01 ± 0.79 0.98 ± 0.64
As August 1.95 ± 0.68 0.96 ± 0.18
  September 1.73 ± 0.24 1.24 ± 0.12
  October 1.28 ± 0.90           0.68 ± 0.22
Se August 10.87 ± 3.24  1.87 ± 0.15
  September 11.32 ± 4.22 9.73 ± 2.45
  October 10.57 ± 4.97 2.76 ± 1.54
Mo August 1.50 ± 0.89 0.35 ± 0.08
  September 1.25 ± 0.77 1.02 ± 0.87
  October 1.75 ± 0.72 1.23 ± 0.93
Ag August 2.30 ± 0.91 1.85 ± 0.77
  September 2.13 ± 0.34 1.34 ± 0.98
  October 1.98 ± 0.96 1.55 ± 0.16
Cd August 3.18 ± 0.77 1.45 ± 0.21
  September 2.01 ± 1.02 1.03 ± 0.88
  October 1.52 ± 0.54 0.37 ± 0.05
Pb August 7.99 ± 3.08 3.83 ± 1.77
  September 1.02 ± 0.73 0.98 ± 0.12
  October 4.33 ± 1.67 2.36 ± 0.46
Table 3: Mean trace metal concentration in the body tissues of Melanoides tuberculata (ppm) upstream of the effluent outfall in Alaro stream