What’s lurking in your shampoo?
These are some of the most common potential toxins found in shampoos:
|1.||IODOPROPYNYL BUTYLLCARBAMATE||Reproductive system toxicity.|
||Possible human carcinogen.|
|4.||FDC YELLOW 6||Possible human carcinogen.|
||Reproductive system toxicity.|
|6.||SODIUM LAURYL SULFATE||Gastrointestinal toxicity.|
|8.||TOCOPHERYL ACETATE||Immune toxicant.|
|10.||DISODIUM EDTA||Penetration enhancer.|
But are these chemicals really toxic at the levels that we encounter them in shampoos?
Where’s the evidence?
Iodopropynyl butylcarbamate was originally made to be used in metalworking and as a wood preservative. As it is a biocide, it is used in body care products (Source) and the maximum permitted concentration is .1%. This product has been linked to allergic contact dermatitis (see picture below) (Source). It is able to penetrate the skin well because it is lipophillic (dissolves well in the fat of our skin). I did not find any evidence that it can cause reproductive system toxicity.
Allergic contact dermatitis
Lecithin is a naturally occurring lipid found in both plants and animals. This is why it is able to help chemicals penetrate our bodies.
Resorcinol is linked with allergic contact reactions (Source). I was unable to find support that it can cause cancer. In fact, it was tested at the University of California at Berkeley and it was found to not be carcinogenic (Source). At very high doses, it can disrupt thyroid function, however, these dosages are not attainable via shampoo (Source)
FDC Yellow 6 is a synthetic dye made from petroleum. It is FDA approved for use in food, pharmaceuticals and cosmetics. There is very little evidence this compound causes any immune toxicity as indicated.
Parabens are synthetically produced compounds which can mimic estrogen. They have weak estrogenic activity and can induce the growth of breast cancer cells (Source). They can also inhibit cells’ mitochondria which is where our cellular energy is made (Source). As parabens have weak estrogenic activity, their role as a cancer causing agent is still under contention. This paper is a great review on the literature about parabens and studies that have been done to determine their activity.
Sodium Lauryl Sulfate (SLS) is actually used to induce contact dermatitis in mice models (Source). This suggests it can also cause dermatitis in humans. I was unable to find any significant evidence for it causing GI irritation.
Propylene Glycol is a small organic alcohol which can cause contact dermatitis (Source)
Tocopheryl Acetate is chemical compound made of acetic acid and tocopherol (vitamin E) which can cause contact dermatitis (Source)
Disodium EDTA is a chelating agent (means it binds to metal ions). It has been linked to contact dermatitis and periorbital (around the eye) dermatitis (Source)
There is a lot of preliminary data suggesting the compounds in our shampoos could be causing reactions ranging from an allergic skin eruption to cancer. Although a large body of definitive evidence does not exist, the preliminary studies indicate these compounds may not be things we want to be exposing ourselves to on a daily basis.
Are there alternatives?
Yes! And the good news is that they can be affordable.
I use Dr. Bronner’s Castille Soap for my shampoo. I buy it at Target and a large bottle costs about $17. This bottle lasts forever because I dilute it with water. Castille soap doesn’t result in very much lather but cleans hair very well. I no longer have to use gel in my hair to keep it from getting frizzy. If my hair is extra knotted, I will use some natural conditioner to help me comb it through.
There are other alternatives to Dr. Bronner’s and you can see them here.
If you are interested in seeing how safe your shampoo is, plug it into EWG’s data base here.
Also, before you buy shampoo, you may want to check out EWG’s database as not all body products that claim to be “all-natural” really are.
What shampoo do you use? Does your shampoo have potentially toxic ingredients in it?