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Last updated on September 15th, 2017
Do you want to know how by looking at a shampoo ingredients for just 1 second, you can avoid buying potentially toxic shampoos? I will tell you right now using Head & Shoulders Classic Clean shampoo as an example.
I spent over 5 years obsessively reading all of the ingredients for each shampoo I can find, which allowed me to develop this method, which is very simple.
Pick up a bottle of shampoo and look at the end of its ingredient list. If you see two words that are long, unpronounceable, and both start with the letter M (namely, methylchloroisothiazolinone and methylisothiazolinone), put the shampoo back on the shelf. Using this method, you will eliminate over 50% of the most potentially harmful shampoos, in my opinion. Why? Find out next.
First of all, these two M ingredients are commonly used. Second, they are potentially very harmful on their own. And third, in my experience, there is a 99% correlation with the fact that other ingredients in the shampoo formulation won’t be good either.
Methylchloroisothiazolinone and methylisothiazolinone in Head & Shoulders Classic Clean Shampoo
Methylchloroisothiazolinone/Methylisothiazolinone (MCI/MI) is a preservative mixture at a fixed combination (ratio 3/1), which is commonly used in cosmetic and industrial applications and can be found in cosmetics, especially shampoos, dermatological products (mainly sunscreens), household cleaning products, paints, moist toilet paper, and metalworking fluids.
Recent reports have shown an increase in sensitization to both MCI/MI and MI by itself. The global frequency of sensitization to MCI/MI remained constant at around 2.1% from 1998-2009, but increased to 3.9% in 2011.
Methylisothiazolinone (MI) was the American Contact Dermatitis Society Contact Allergen of the Year for 2013 because its use in cosmetics and personal care products is rising.
What is sensitization?
It is important to note here that skin irritation is different from sensitization. A sensitizer is defined by OSHA as “a chemical that causes a substantial proportion of exposed people or animals to develop an allergic reaction in normal tissue after repeated exposure to the chemical.” In other words, if a chemical causes irritation, you will see it on the first use. With sensitizing chemicals, you may not have an allergic reaction to a product at first and develop an allergic reaction after prolonged use.
Once a person is allergic, he or she is always allergic. The body won’t forget it and the only way to prevent an allergic reaction is avoidance (source).
Other ingredients that I underlined in red (e.g. worst) in Head & Shoulders Classic Clean Shampoo
Sodium Laureth Sulfate
Every foaming shampoo has to have foaming agents, also known as surfactants. There are two surfactants in the Head & Shoulders Classic Clean Shampoo – Sodium Lauryl Sulfate (SLS) and Sodium Laureth Sulfate (SLES). SLES is created by taking Sodium Lauryl Sulfate and adding ethylene oxide, in a process called ethoxylation. The problem with this process is that ethylene oxide is a carcinogen and if the manufacturer does not use the vacuum stripping method, the by-product of this process, 1,4-dioxane, linked with cancer, may remain in the final product. There is no way for us consumers to know if vacuum stripping took place. I recommend avoiding shampoo and all other personal care products with ethoxylated ingredients.
“Fragrance” is an undisclosed mixture of various scent chemicals and ingredients used as fragrance dispersants. Phthalates are likely to be present in the mixture because they are often used in creating a fragrance so it is statistically likely, although this is my opinion and I simply don’t know if they are used here.
There are a number of different phthalates and some of them are possible carcinogens and hormone disruptors (for detailed information on phthalates, read my phthalate primer here).
Fragrance mixes have been associated with allergies, dermatitis, respiratory distress and potential effects on the reproductive system. They are rated 8 out 10 (10 being most toxic) in the Skin Deep database.
I highly recommend that families with babies and small children stay away from fragrances, as well women who are planning to conceive or who are pregnant.
Blue 1, Red 33
Blue 1 (CI 42090) and Red 33 (CI 17200) are synthetic colorants.
Colorants can be of mineral or synthetic origin. The synthetic dyes are organic, which means that they contain carbon compounds, i.e. the term “organic” is a reference to organic chemistry, and are derived from petrochemicals, as opposed to being USDA “certified organic.” (In other words, they are “organic” in a bad way!) Both mineral and organic pigments and dyes may contain traces of heavy metals as detailed in the Code of Federal Regulations, FDA 21 CFR.
In addition to heavy metal contamination, organic pigments and dyes may contain traces of additional contaminants specific to petroleum, including carcinogenic and endocrine disrupting benzo[a]pyrene, and PAHs (polycyclic aromatic hydrocarbons).
You can see a list of potential contaminants for Red 33 here.
According to the Canada Environment Substances List, both Blue 1 and Red 33 are persistent in the environment, meaning that they are not easily degradable and remain in the environment for a very long time.
And lastly, synthetic dyes are tested on animals due to their potential carcinogenic properties.
And do we really need colorants in our shampoo? With the detailed concerns about Red 33 and Blue 1, I highly recommend avoiding shampoos with any colorants. Was your day really ruined because your shampoo didn’t have any color to it? I didn’t think so.
This concludes my review of the worse ingredients in Head & Shoulders Classic Clean Shampoo.
What is next?
Please let me know in the comments if you are interested in continuing our conversation on how to avoid the other 50% of most potentially toxic shampoo.
2017 Shampoo and Conditioner Guide is out. Check it out here.
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