Figure 4: TEM of P. reticulata intestinal nuclear cells showing control fish and exposed fish, Intact cytoplasmic and nuclear membrane with welldefined nucleus (N) and one nucleolus (NU). Cell organelles are intact as in Mitochondria (M); Lysosomes (Ly); Rough Endoplasmic Reticulum (RER); Smooth Endoplasmic Reticulum (arrow) scale bar 1μm.