List of Harmful Chemicals in Hair Dye

Have you heard about harmful ingredients in hair dyes and the risks they pose to health? Indeed, because they contain a hair shaft opening ingredient, permanent hair dyes change the structure of your hair cuticle and, thus, can leave your hair prone to breakage. Further, permanent hair colorants are associated with such health risks as skin irritation, scalp irritation, allergic reaction, and hair loss. What’s more, some ingredients in hair dyes are even potential hormone disruptors and carcinogens. Yet, hair coloring products continue to be part of beauty routine for many people.

Since 2017, I Read Labels For You has been doing research in the field of permanent hair colors. Today, you have a unique opportunity to take advantage of our unprecedented study of the ingredients of major permanent hair color brands. Thus, in this post, we will go over a list of ingredients suggested by Internet browsers as “harmful ingredients in hair dyes.” On the one hand, you will see which of these ingredients are common and truly harmful chemicals in hair dyes. As well as how you can avoid them. On the other hand, you will see which of these ingredients are not worth focusing on when deciding on the safety of a permanent hair color and why.

List of Harmful Chemicals in Hair Dye

I started dying my hair in my early 20s when I didn’t have a need for it whatsoever. I did it just because everyone else was doing it.  (“Ahh, youth!”)  Moreover, I didn’t know anything about products’ ingredient lists, or that ingredients may be harmful for health. Naively, I believed that if skincare, hair coloring or hair care products said they were made of “natural ingredients,” they were 100% safe.

Ironically, an allergic reaction to an eye cream in 2012 opened my eyes (after first painfully shutting them!) and made me realize the importance of reading and understanding the ingredients in the products I applied on myself. Hence, today, as I’m approaching 50, I use advanced skin care that is both effective and non-toxic. 

As for hair coloring products, after years of research, I have come to the conclusion that there is no such thing as a “non-toxic” or “safe” permanent hair dye. Some of them can be safer than others due to the absence of certain harmful chemicals. But no permanent hair color is safe in absolute terms.

Although I stopped coloring my hair years ago (because I embraced my grey hair as part of who I am), I am fully aware of the fact that not everyone is ready to bid farewell to hair coloring products. Hence, I created a Permanent Hair Color Rating List E-Book, introducing more than 60 popular hair color lines, to help you choose a safer product based on its ingredients.

Ingredients Of Higher Concern When Choosing A Permanent Hair Dye

If you want to choose a safer permanent hair color, this is the group of ingredients to which you should pay special attention. The presence or absence of some of them can truly make your hair coloring product safer for you.

They include hair shaft opening ingredients, permanent hair colorants, and some other harmful chemicals. The good news is that you can avoid them by choosing a product without these harmful ingredients. 

So, the ingredients worth focusing on when choosing a permanent hair dye include:

• ammonia
• fragrance
• phthalates
• PPD
• propylene glycol, and
• resorcinol.

It is a good idea to know something about these ingredients in hair dyeing products. This way, you will not be deceived by marketing claims.

Ammonia

To begin, sometimes ammonia-free hair color brands boast that they do not use ammonia. But usually, it only means that they use ethanolamine. Which is not safer than ammonia in my opinion.

Indeed, ammonia and ethanolamine function as hair shaft openers that let hair dyes into the hair to subsequently change its color. Most permanent hair coloring products can’t do without them.

As for ammonia and ethanolamine, both are corrosive and damage the hair. However, when researchers applied different methods to measure hair cuticle damage and protein loss, they found that there was more hair damage from ethanolamine than from ammonia. In some extreme cases, as much as 85% more (source). Additionally, this study found that hair colors with ethanolamine versus ammonia are more likely to cause hair loss.

In other words, if a permanent hair color does not contain ammonia, it will most likely contain ethanolamine. And that appears to be more problematic. The good news is that you don’t have to guess. In my Permanent Hair Color Rating List E-Book, you will instantly have access to a list of over 60 hair dyes. And know which ones contain ammonia or ethanolamine – or neither.

Fragrance

Listed as “fragrance” or “parfum,” this ingredient is present in the majority of hair color lines included in my Permanent Hair Color Rating List E-Book (but not in every one!). I believe its main function in this case is to mask an unpleasant odor of the many potentially harmful chemicals used in the product’s formulation.

However, as one of the ingredients in hair color, fragrance is not that benign either. As a matter of fact, it usually consists of multiple ingredients that companies prefer not to disclose. Hence, we cannot be sure that their fragrance mixtures do not contain allergens, sensitizers, carcinogens, or hormone disruptors. And “natural fragrance” is not an exception.

In sum, if you want to avoid hair coloring products with fragrance, get my Permanent Hair Color Rating List E-Book. By using the search engine (Ctrl+F), you will know right away which colors have fragrance and which ones don’t.

Phthalates

First of all, you will not see phthalates listed as separate ingredients in hair dyes. They may appear in a product as part of fragrance.  Here are some examples of phthalates that are used in fragrance.

Dibutyl phthalate is toxic to reproduction and may cause damage to the unborn child (source). 

Next, diethyl phthalate (DEP) is under assessment as an endocrine disruptor (source). Additionally, in human studies, exposure to DEP in a mixture of phthalates repeatedly showed adverse reproductive outcomes. Including changes in hormone levels, poor semen quality, and genital development (source).

And di(2-ethylhexyl) phthalate is toxic to reproduction and is endocrine disrupting (source). Also, the US National Toxicology Program classifies it as “reasonably anticipated to be a human carcinogen.”

When manufacturers do not disclose the ingredients of their fragrances, we cannot be sure that there are no phthalates in them, even when they tell us their fragrances do not contain phthalates. As I mentioned above, most hair colors included in my Permanent Hair Color Rating List feature “fragrance” (aka “parfum”) as an ingredient. The good news is that there are some hair color lines that do not have fragrance among their ingredients. So, if you want to avoid exposure to phthalates, get my Permanent Hair Color Rating List E-Book. You can instantly know which products have fragrance and which ones don’t.

PPD

Used as a hair colorant (aka “pigment” or “dye”), p-phenylenediamine (PPD) is a common ingredient in permanent hair colors. And belongs in the group of “extreme” sensitizers (source). That is to say, an allergic reaction to hair dye with PPD may develop over time. And with repeated use of the product.  (This is why it is critical to patch-test your hair dye before every application.)

As compared to other extreme sensitizers, such as toluene-2,5-diamine (PTD) or toluene-2,5-diamine sulfate (TDS), the frequency of allergic reactions to PPD is higher. Allergic reactions to PPD may include shortness of breath, loss of consciousness, and even death. For this reason, I gave it the highest (read: “worst”) rating of 18 in my Permanent Hair Color Rating List E-Book. This means I consider it the least safe out of all the rated ingredients in hair colors.

Oftentimes, permanent hair coloring products use toluene-2,5-diamine sulfate (TDS) or toluene-2,5-diamine (PTD) instead of p-phenylenediamine (PPD). However, they are also extreme sensitizers. And the frequency of allergic reactions to these ingredients in both hairdressers and consumers remains a considerable concern for consumer safety (source). However, because the frequency is lower than that of PPD, the rating I assigned to TDS and PTD is 14 (versus 18 for PPD).

By the way, out of more than 60 permanent hair coloring products I analyzed for my e-book, four do not list extreme sensitizers among their ingredients. If you would like to choose a permanent hair color without PPD, TDS, or PTD, you can do so by referring to an easy-to-use rating table in my Permanent Hair Color Rating List E-Book. In the table, you will easily see which hair colors have extreme sensitizers and which ones don’t.

Propylene Glycol

To start with, propylene glycol is an aliphatic alcohol that functions as a skin conditioning agent, viscosity decreasing agent, solvent, and fragrance ingredient in cosmetics. In addition, they use it in processed food and oral, intravenous, and topical pharmaceutical agents.

The good news is that propylene glycol is not a carcinogen (source).  Furthermore, it is potentially toxic to the body only when ingested or intravenously delivered in high doses frequently (source). 

According to the Cosmetic Ingredient Review (CIR) Expert Panel’s safety assessment of propylene glycol as used in cosmetics, propylene glycol is generally non-toxic when used topically in products we apply on our bodies. Although clinical studies showed that the risk of sensitization is very low, there are some concerns about skin irritation.

Importantly, the CIR Expert Panel did note that propylene glycol may act as a penetration enhancer. In other words, if it enhances penetration of harmful ingredients, they should not be present in the product. Which is not the case with hair colors.

If you would like to avoid permanent hair color lines that contain propylene glycol, you can do so by accessing my Permanent Hair Color Rating List E-Book. As a matter of fact, about half of the hair colors included on the list are free of propylene glycol. You will instantly know which colors contain this ingredient by finding the ingredient through the search bar (Ctrl+F).

Resorcinol

Another hair colorant (aka “pigment” or “dye”), resorcinol belongs in the group of “moderate” sensitizers (source). As a reminder, a sensitizer is an ingredient that may trigger an allergic reaction after repeated exposure to a product containing this ingredient.

In addition, it is under assessment as endocrine disrupting by the European Chemicals Agency (ECHA) and is mentioned in the Endocrine Disruption Exchange database. On the bright side, I haven’t come across a study that proves that the amounts of resorcinol absorbed from a hair dye are sufficient to suppress the thyroid.

Currently, about 20 hair colors included in my Permanent Hair Color Rating List do not feature resorcinol among their ingredients. So, if you would like to avoid resorcinol, get my Permanent Hair Color Rating List E-Book and have instant access to the names of hair colors without this harmful ingredient.

Ingredients Of Lower Concern When Choosing A Permanent Hair Dye

This group of ingredients does not affect the general degree of safety of your permanent hair dye as much as the ingredients discussed above.

Indeed, as compared to permanent hair colorants and hair shaft openers, these ingredients are secondary and are not a final say in your decision.

Moreover, some of the chemicals in this group are not even common in permanent hair dyes. Therefore, when a hair color brand markets itself as “XX-free” when “XX” is normally not even used in hair dyeing products in the first place, it sounds like an ungrounded marketing claim.

So, among the ingredients suggested by your Internet browser as “harmful ingredients in hair dyes,” in my opinion, the following ones are not worth stressing about when choosing a permanent hair dye:

• alcohols
• coal tar
• formaldehyde
• hydrogen peroxide
• lead acetate
• parabens
• silicones, and
• sulfates.

Alcohols

Although some ingredients contain the word “alcohol” in their names, they are not alcohols in the common sense of the word due to a different chemical structure. Some examples include:

• behenyl alcohol
• benzyl alcohol
• cetearyl alcohol
• lauryl alcohol
• myristyl alcohol, and
• stearyl alcohol.

While such alcohols as ethanol and rubbing alcohol can dry the skin and cause itchiness, flaking, and peeling, cetearyl alcohol and behenyl alcohol are fatty alcohols that have a waxy texture and function as emulsifiers. Specifically, they help soften the skin and improve the texture and consistency of the formulation.

As for benzyl alcohol, it is an aromatic alcohol used in cosmetic formulations as a natural preservative. 

Coal Tar

For starters, coal tar is a byproduct of coal processing that is sometimes used in skincare products to treat psoriasis and other skin conditions. It has been linked to the “hair dyes and cancer” issue. 

Now, the FDA refers to hair dyes (aka “pigments” or “colorants”) as “coal-tar hair dyes”. Because, originally, they were by-products of the coal industry.

However, this is not necessarily true anymore.  Not all so-called “coal-tar hair dyes” are made from by-products of the coal industry.

Additionally, the FDA does not regulate hair dyes and openly says that it is the consumer’s responsibility to do their own research on their safety and take the necessary precautions against the risks.  (Obviously, I have done a lot of that for you.  See my Permanent Hair Color Rating List E-Book!)

Regardless of what hair dyes (aka “colorants”) were sourced from – coal tar, petroleum or anything else – in the end, the Scientific Committee on Consumer Safety (SCCS) classifies them as “extreme,” “strong,” and “moderate” sensitizers. The attribute refers to their potential to cause an allergic reaction after repeated use of the product containing this ingredient.

Examples of extreme sensitizers are p-phenylenediamine (PPD), toluene-2,5-diamine (PTD), toluene-2,5-diamine sulfate (TDS), n-phenyl-p-phenylenediamine (sulfate) (NPPPD), and 2,6-diaminopyridine. And resorcinol, which is potentially endocrine disrupting, is a moderate sensitizer.

You can avoid any of these by choosing a hair color free of these sensitizers. Download my Permanent Hair Color Rating List E-Book and have immediate access to the names of hair coloring products that are free of extreme sensitizers and/or resorcinol.

Formaldehyde

True, it’s best to protect yourself from formaldehyde in products as it is a known carcinogen and sensitizer.

Often, ingredients lists do not contain formaldehyde per se. But they may still have it as a contaminant of other ingredients referred to as “formaldehyde-releasers.” Some common formaldehyde-releasers that act as preservatives in products include:

• 2-bromo-2-nitropropane-1,3-diol
• diazolidinyl urea
• DMDM hydantoin
• glyoxal
• imidazolidinyl urea
• methenamine
• quaternium-15
• polyoxymethylene urea, and
• sodium hydroxymethylglycinate.

The good news is that out of more than 60 hair color lines analyzed in my Permanent Hair Color Rating List, only one lists one of these ingredients, namely imidazolidinyl urea. My educated guess is that permanent hair colorants are strong enough to kill all potential bacteria. Hence, permanent hair coloring products do not need any additional preservatives, like the formaldehyde-releasers mentioned above.

So, there is no need to waste your time trying to find a hair color without formaldehyde. But if you’d like to avoid the one hair color that uses imidazolidinyl urea as a preservative, you can quickly find it in my Permanent Hair Color Rating List after you purchase and download it.

Hydrogen Peroxide

An oxidizing agent, hydrogen peroxide functions as a developer by dissolving the natural hair pigment and helping to initiate the color forming process. When used on its own, it bleaches your hair. Or makes it lighter in color after lifting the natural melanin from the hair. When mixed with other chemicals in a hair dye mixture, it oxidizes and bonds with them to provide the hair color you desire.

Ultimately, hydrogen peroxide works in the innermost part of the hair that holds the pigment that gives hair its color. As a result, it can strip the hair of its natural moisture and oils. And leave your hair prone to breakage. Plus, it can cause overall damage to the hair shaft that may lead to hair loss. Which is just one of the most overlooked hair loss causes.

Every permanent hair color must have a developer to initiate the process of changing color. Hence, hydrogen peroxide is one of the common ingredients in hair coloring products of permanent nature. It means that trying to find a permanent hair color without this ingredient is a waste of time, in my opinion.

Lead Acetate

According to Consumer Reports, lead acetate is a key ingredient in so-called “progressive” hair dyes, typically targeted at men. To clarify, such hair dyes work by gradually coloring grey over time as opposed to typical single-use dyes.

None of the hair color lines included in my Permanent Hair Color Rating List lists this ingredient.

Parabens

Some health risks associated with parabens that function as preservatives are endocrine disruption and an increased risk of cancer (source and source). To be fair, the estrogenic effects differ among parabens, are generally not strong. And some animal studies were inconclusive and controversial.

Nevertheless, the European Commission banned the following parabens from use in cosmetic products:

• benzylparaben
• isobutylparaben
• isopropylparaben
• phenylparaben, and
• pentylparaben.

Alternatively, the European Commission allows the following parabens in cosmetic products:

• methylparaben
• butylparaben
• ethylparaben, and
• propylparaben.

In my Permanent Hair Color Rating List E-Book that you can download right now, out of more than 60 hair color lines, only four list parabens from the second group (allowed for use in cosmetic products by the EU Commission). And no hair color included in the Rating List features parabens from the first group (banned from use in cosmetic products).

I believe parabens, or any other preservatives, are not that common in permanent hair coloring products due to the presence of strong chemicals, such as permanent hair colorants and hair shaft openers, that are capable of killing bacteria. Thus, these products do not need any additional preservation system.

Silicones

What is important to know about silicones is that they can be “linear” or “cyclic”. And their safety data differs drastically.

For instance, one example of linear silicones is dimethicone. In my opinion, based on my research, dimethicone is safe enough to belong in toxin-free makeup and cosmetic products.

Conversely, based on my research, I find cyclic silicones, such as cyclopentasiloxane (D5) and cyclotetrasiloxane (D4), a bit concerning.

While several hair color lines analyzed in my Permanent Hair Color Rating List E-Book list dimethicone as a stand-alone ingredient, none of them list cyclopentasiloxane or cyclotetrasiloxane. Hence, I believe silicones are not so much part of “harmful chemicals in hair dye” list.

Sulfates

Basically, “sulfate” means “salt” and is not that scary as an ingredient (except in colorants) unless used in large quantities, when it can be drying.

As for Sodium Lauryl Sulfate (SLS), it is not so common in permanent hair coloring products and is most likely used as a surfactant.

Oftentimes, people confuse Sodium Lauryl Sulfate (SLS) with Sodium Laureth Sulfate which belongs to a group of ethoxylated ingredients. (You can identify those by the “-eth” ending, PEG, and Polysorbate plus number.) Being hidden ingredients in cosmetics, ethoxylated ingredients arouse some concern. Because they may contain residues of carcinogenic ethylene oxide and 1,4-dioxane.

In sum, SLS is not common in hair dyes, to begin with. Even if it is used, it does not pose as much risk as compared to that posed by other harmful chemicals such as permanent hair colorants and hair shaft openers that must be present in permanent hair coloring products.

Summary Of Harmful Chemicals In Hair Dye

In My Opinion, On The List Of Harmful Chemicals In Hair Dyes, The Ingredients Of Significantly Higher Concern Are Ethanolamine, Fragrance, Phthalates, Resorcinol, And PPD.

In this post, we went over a list of harmful chemicals in hair dyes suggested by Internet browsers and saw that some ingredients are of much higher concern than others. While the degree of safety of a permanent hair color may vary to some extent, there is no such thing as a “safe” permanent hair color in absolute terms.

Please be aware that sometimes when companies market their products as “XX-free,” it means that they are using another ingredient instead that is not necessarily safer. An example of that is ammonia-free hair colors, These products use ethanolamine instead which poses even more serious health risks than ammonia.

The Good News

The good news is that by taking advantage of the I Read Labels For You blog and research, you don’t have to rely on marketing claims or random information on the Internet. Indeed, anyone can publish anything on the Internet!

What sets us apart is that we do original research. Specifically, in the field of hair coloring, we have been studying the ingredients of major hair dye brands since 2017. The results of this research are compiled and presented in our unprecedented Permanent Hair Color Rating List E-Book. We find it important to update the e-book annually, though it is rather time-consuming and at times unappreciated. Because manufacturers can, and do, frequently change their products’ formulations. Actually, after purchasing our e-book, one of the European hair color manufacturers reformulated their permanent hair color to make it significantly safer and wrote to tell us that. We consider this a major breakthrough! (They do ship to the US.)

If you would like to choose a permanent hair dye based on the safety ranking of its ingredients, or if you would like to instantly know which hair color brands contain or do not contain resorcinol and/or extreme sensitizers, be sure to get our unprecedented and popular Permanent Hair Color Rating List e-book!

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