Effects in Microorganisms, Plants, and Water Organisms

As discussed in Section 7.3.2, hexavalent chromium inhibits the nitrification process in activated sludge. However, organic substrate removal was not affected, which indicated that the various microorganisms might have different sensitivity to chromium (Vankova etal. 1999 Stasinalds etal. 2003). 

The potential of several plants to accumulate chromium was assessed for purposes of bioremediation of tannery effluents. ValUs-neria spiralis L. (a rooted and submerged plant) accumulated 1378 mg Cr kg dry weight of leaves, but there was a decrease in chlorophyll and protein concentrations as chromium levels increased (Sinha et al. 

Hexavalent chromium exerted an inhibitory effect on maize growth and development, with cob development being affected at Cr levels of 0.25, 0.5, and 1.0 mM. Amylase activity was decreased at higher chromium levels, and there was severely reduced grain yield after 80 days of exposure to chromium (Sharma et al. 

Chromium-intoxicated bass did not show any change in their feeding habits, though alkaline phosphatase activity decreased and Na/K ATPase increased both changes might be useful indicators of chromium intoxication in fish (Boge et al. 1988). 

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