Using hair color, whether permanent or temporary, always presents a problem greater than trying to decide which shade is going to look best on you: what do you do with the leftover dye? If you have short hair, most of the product may be destined for the drain. But, not only can the chemicals in hair dye damage plumbing, they can travel into soil and groundwater. Fortunately, there are better and safer ways to dispose of dye.

Modern bathroom vanity and bathtub
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Understand Why it Matters

You may not realize it, but the chemicals used to bind color to your hair strands are actually classified as hazardous wastes. In addition to being suspected or known cancer-causing agents, some of these chemicals are also harmful to the environment. For example, benzenediamine dihydrochloride, also listed as phenylenediamine or PPD, is used in hair dye to fix color onto hair and is highly toxic to fish and wildlife, with long-lasting effects in water and soil. Ironically, the French scientist who formulated the first chemical hair coloring with PPD in 1909 launched a company called the French Harmless Hair Dye Company, better known today as L'Oreal.

Sharing Is Good

Got a friend who fancies the same shade as your choice in hair color? Plan a day when you can both take the time to color at the same place, sharing the same product. This way, there is less or no leftover hair dye to dispose of and the bottle(s) can be placed in the recycling bin after a quick rinse. As an added bonus, this is an opportunity to color each other’s hair and finally avoid missing spots that always seem to occur when going it alone. In this case, two heads really are better than one.

Donate the Dye

If you have unopened hair dye you no longer need, consider donating to a nursing home or assisted living facility willing to accept it for use in their on-site salon. This isn’t always possible, though. First, many centers will not accept even sealed personal care products out of understandable concern for the safety of residential clients, as well as concern over potential legal ramifications. Alternatively, a different route to donation might be a local women’s shelter. Of course, you could also gift it to a friend or family member who can use it.

Locate Local Resources

Check with your local municipality to see if there's a household waste program in place where you can drop off leftover hair dye (and other products, like paint and household cleaners). If your community doesn’t have one, you can locate hazardous waste collection and recycling centers near you by calling 1-800-CLEANUP (800-253-2687) or by visiting Earth911.com to do a "Where to Recycle" search using your ZIP code.

Consider Natural Dyes

There are several plant-based hair dyes on the market today that present far fewer adverse effects in human or environmental health. Similarly, henna is a great, safe alternative for natural and eco-friendly hair coloring where leftover product becomes compost instead of hazardous waste. Check with your hair stylist or colorist for more about these products and how to use them.