Effect of keratin on heavy metal chelation and toxicity to aquatic organisms

摘要

The presence of fresh scales and human hair in water can reduce the t oxicity of lead nitrate at and above 6 ppb to fish. This ability is lost on drying and storage, but can be restored if dried hair or scales are treated with a solution of amino acids. The chelation ability of keratin in amino acid-treated scales or hair is retained for months on dry storage. Addition of these hair and / or scales to solutions of lead nitrate (112 ppm), mercuric chloride (5.9 ppm) and a mixture of both (56+2.95 ppm). and cupric sulfate (1 ppm) reduced the toxicity of these solutions to Daphnia magan and Dreissena polymorpha (zebra mussles). Toxicity of 10 ppm solutions of salts of 27 different metals to daphnids was similarly reduced after filtration through scales or hair.