Antagonistic Effects of Sublethal Concentrations of Certain Mixtures of Metal Oxide Nanoparticles and the Bulk (Al2O3, CuO, and SiO2) on Gill Histology in Clarias gariepinus
Table 2
A 28-day single and joint exposure of Clarias gariepinus to nanosize metals.
Conc. ratio
Nanometals
Assumed HAI
Toxic level
Actual HAI
Toxic level
Type of joint effect
Gill pathology
Singly
SiO Al2O3 CuO
20.0 2.0 10.0
High Low Moderate
NA NA NA
NA NA NA
NA NA NA
EGL, hypertrophy Oedema Necrosis
1 : 1
SiO + Al2O3 SiO + CuO
22.0 30.0
High High
2.0 6.0
Low Low
Antagonistic Antagonistic
Hypertrophy, SSGL
2 : 1
SiO + Al2O3 SiO + CuO
22.0 30.0
High High
8.0 6.0
Low Low
Antagonistic Antagonistic
EH, SSGL
1 : 2
SiO + Al2O3 SiO + CuO
22.0 30.0
High High
16.0 6.0
Moderate Low
Antagonistic Antagonistic
PEC, EPL, necrosis
1 : 1 : 1
SiO + Al2O3+ CuO
30 or 22
High
6.0
Low
Antagonistic
EGL, SSGL
Toxic level: HAI: X < 10, low; 10 ≥ X < 20, moderate; X ≥ 20, high.