How To Color Your Hair Without Harming The Environment

Is your hair environmentally friendly? It's an organic compound and is biodegradable (taking anywhere from 12 to 24 months to break down). Provided proper waste management procedures are followed, the hair removed from your head at the salon won't pose an environmental threat. But what about if you color your hair? If you want to be kind to nature, does this mean you have to stick with your hair's natural color?