The toxicity of chlorine to a common vascular aquatic plant

C.H. Watkins; R.S. Hammerschlag

doi:10.1016/0043-1354(84)90256-2

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The toxicity of chlorine to a common vascular aquatic plant

C.H. Watkins·R.S. Hammerschlag

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Abstract

Myriophyllum spicatum was exposed to various chlorine concentrations on a continuous and intermittent basis in 96-h toxicity studies utilizing a proportional diluter. Continuous exposure to chlorine concentrations as low as 0.05 mg l −1 total residual chlorine (TRC) depressed shoot and total plant dry weights approx. 30% relative to controls. Shoot length was depressed approx. 16% at this concentration. Chlorophyll a was depressed 25% at 0.1 mg l −1 TRC. However, intermittent exposure of plants to chlorine for three 2-h periods daily for 96 h indicated an insensitivity to repeated short term chlorine exposure at all concentrations but 1.0 mg l −1 TRC. These results indicate that high level chlorine discharges from waste water facilities and electric generating plants could be a contributing factor impacting nearby submerged aquatic vegetation.

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C.H. Watkins, R.S. Hammerschlag. 1984. The toxicity of chlorine to a common vascular aquatic plant. https://doi.org/10.1016/0043-1354(84)90256-2

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