There are a variety of products claiming to be “cleaner” than conventional hair dyes, but are they actually safer?
Somewhere between 66-74 percent of women use hair-coloring products. Many companies began offering “organic” products as concerns about the toxicity of some of the chemicals used in permanent or semi-permanent hair dyes rose… This gives consumers the impression that the products have safer, cleaner, non-toxic ingredients. Unfortunately, this is mostly a marketing gimmick.
”Hair dye” is a broad term referring to many kinds of products. They can be natural, like henna, which is derived from the henna tree, or synthetic. Synthetic dyes can be temporary, semi-permanent, or permanent. Generally speaking, natural dyes are temporary and last only a few weeks because the pigment from the dye is only penetrating the outer layer of the hair shaft. Semi-permanent and permanent hair dyes reach deeper into the hair shaft and last longer, but this effect requires a number of chemicals, several of which are associated with safety concerns.
Semi-permanent or permanent hair dyes work by using ammonia (or ethanolamine in the case of some ammonia-free products), hydrogen peroxide, and p-phenylenediamine (PPD) or one of its substitutes (PTD, or para-toluene diamine or p-aminophenol). Ammonia pulls apart the hair’s layer of proteins so the dye can penetrate. Hydrogen peroxide bleaches the hair and helps PPD, the coloring agent, adhere to the hair.
PPD is of particular concern because it has been linked to cancer, as well as blood toxicity and birth defects. According to the Environmental Working Group’s Skin Deep database, PTD and p-aminophenol, PPD substitutes, are also concerning, rated a 6 and a 7 (10 being the most toxic). An expert writing for the United Kingdom’s Royal Society of Chemistry remarked that, “It’s probably true that if these materials (PPD and PTD) were invented today, their use in cosmetics would not be permitted but they remain in use…as no effective replacements have been found.”
If you’re looking for permanent hair dyes, they will contain PPD or one of its substitutes, along with many other chemicals like resorcinol. We’ve seen something similar play out before. When BPA started being linked to a host of negative health effects, “BPA-free” became a common marketing slogan on products. They may have been BPA-free, but many used a substitute called BPS, which was just as toxic as BPA. Similarly, there are many hair dyes that claim to be “PPD-free” but contain one of these substitutes that are not necessarily safer.
There are several other concerning ingredients used in hair dyes you need to avoid. Ethanolamine, a common substitute for ammonia, has been linked to birth defects and hair loss. Although it is not commonly used any more, lead acetate can be found in some products on the market. Lead is a neurotoxin, and there are no safe levels of lead exposure. Resorcinol, a hormone disruptor, is another common ingredient.
Methylisothiazolinone and methylchloroisothiazolinone are preservatives that can cause serious allergic reactions, even in people who do not usually have allergies. Formaldehyde, a known carcinogen, and benzene, which is associated with leukemia, are also added to hair dyes. These chemicals can be absorbed through the skin and directly enter the bloodstream. They can also soak down into the hair follicle, which is highly vascularized.
Because of these ingredients, hair dyes are known to be toxic. They can cause skin damage and allergic reactions. Exposure to the eyes can cause anything from mild irritation to loss of vision. Unintentional swallowing can cause life-threatening allergic reactions. Unfortunately, due to these dangers, hair dyes have been used in the developing world as a form of self-harm. Some studies have found hair dyes increase the risk of non-Hodgkin’s lymphoma, leukemia and bladder cancer, but other studies have found no links to these cancers.
It can be difficult to assign causality given the breadth of our chemical exposures over years, but research looking at salon workers found that they commonly experience skin and respiratory problems. They also had disproportionate rates of cancer. Additionally, the World Health Organization concluded that occupational exposure to hair dyes was “probably carcinogenic.”
There are some PPD-free products on the market, but they are not permanent dyes, and results may only last for a few washes. These products can’t change your hair color from light to dark or vice versa, but they can help conceal grey and add deeper tones to your hair color. Again, outside of temporary dyes, the coloring effect in hair dyes is achieved by the activity of multiple chemicals. If you want to avoid exposure to these types of chemicals, your only option is temporary dyes. Note, too, that it isn’t the case that all temporary hair dyes are safe—many still contain the chemicals discussed above. But there are temporary products available that are made from natural plant powders that do not contain chemicals.
Many of these same dangers also apply to bleach, which involves a chemical reaction with the pigment in your hair to remove the color. Bleach products can contain hydrogen peroxide and ammonium persulfate, which can be poisonous. The chemicals in hair bleach can cause itchiness, contact dermatitis, redness, flakiness, blisters, and burning sensations. There are several alternatives to chemical bleaches for lightening hair, like lemon juice, apple cider vinegar, or chamomile tea.
What about hair dyes being marketed as “organic”?
As far as hair dyes are concerned, “organic” is meaningless. Organic standards are for agricultural products and regulated by the USDA. The FDA, which oversees cosmetics, does not regulate the use of the term “organic” for cosmetics. Some ingredients in these products can be organic—but they usually deal with moisturizing or scalp soothing and have nothing to do with hair coloring. For example, Natulique’s tagline is “Certified Organic Beauty” and their website has pretty pictures depicting the botanicals their products contain. But dig deeper and you see that some of these products also contain things like resorcinol, PPD, and a laundry list of other chemicals.
Women of color appear to be at particular risk. A report by the National Institutes of Health noted an increased risk of breast cancer among all women using hair dyes, but black women in the study had a 45 percent higher risk compared to white women.
What about henna? Henna is derived from the leaves of the henna plant. The powdered leaves are made into a paste and applied to the hair or skin. There are pros and cons of using henna. It can be difficult and tedious to apply, and the color spectrum is limited due to the natural color of henna. But because it doesn’t involve the chemicals of other dyes, it may be a good option for those who want to avoid exposures; though be wary of products with unsafe additives like silver nitrate, carmine, chromium, and others. Some products labeled as “black henna” should be avoided because they contain PPD, which has caused scarring when applied to the skin.
If you want to avoid troubling chemicals, you may want to steer clear of permanent hair dyes entirely and stick to those that are temporary. Even semi-permanent hair dyes may contain the concerning chemicals discussed in this article. Always be sure to be a conscious consumer and read the ingredients list, even if the product says “organic” or “natural.”