In the past few years, there have been increasing numbers of readers who write to me, concerned about the safety of the ingredients in their skin care and cosmetics. I can’t exactly blame them – for someone without a science degree, reading books like Jessica Alba’s The Honest Life or websites like the EWG’s Skin Deep Database would scare me senseless, too. Add in pervasive myths, like, “If you can’t eat it or pronounce it, you shouldn’t put it on your skin,” and you have the makings of a potential skin care revolution. Unfortunately, these seemingly well-meaning sources are typically citing studies that are evaluating 1000s to millions of times the concentrations ingredients are used in skin care and beauty products. And, contrary to popular belief, these ingredients typically do not accumulate in the skin or sensitize your health with regular exposures.
At any rate, one ingredient that has gone under scrutiny as of late is disodium EDTA, a term short for ethylenediaminetetraacetic acid. Despite the fact that it is not a natural food item, I can reassure you, it is safe and useful in the very low concentrations it is used in skin care and beauty products.
What is Disodium EDTA, and Why is it Used in Products?
Disodium EDTA is a preservative and chelator in beauty products.
A chelator sounds like a scary vocabulary term from a chemistry class, but a chelator actually is your friend, “softening” water so it is better for your skin. A chelator will bind to the heavy metal ions in water, which prevents the ions from interacting with your skin, hair, or nails.
Metal ions also become more prevalent in older products that have been exposed to too much light or air. So chelators are effective preservatives, binding to these metal ions, preventing them from reaking further havoc in your products. So products maintain their color, consistency, texture, odor, and cleansing/moisturizing abilities for longer
Is Disodium EDTA Safe?
Yes, disodium EDTA is safe for skin care and cosmetics. A review in the International Journal of Toxicology found that EDTA in even extremely high concentrations – 750 mg/kg/day – did not cause cancer. To give you an idea of a typical exposure from a skin care or cosmetics product, you are looking at less than 0.02 mg – so a study mentioned in the review used 1500x the typical dose of EDTA! The review found that using this 1500x dose of EDTA was “cytotoxic” and “weakly genotoxic,” which, in layman’s terms, means “damages cells when incubated together with them in a petri dish” and “damages or kills cellular DNA when placed in a petri dish”. No toxicity at all was noted when EDTA was used at concentrations below 1500x the typical dose. In fact, the normal dose of EDTA in a skin care or beauty product has been concluded by the Cosmetic Ingredient Review Panel to be “safe” for all intents and purposes (International Journal of Toxicology).
Some websites argue that EDTA is a penetration enhancer for other ingredients, but this is not the case. I have no idea where they are getting this from – disodium EDTA binds to metal ions in heavy water and the solution (solvent) into which it is placed, but does not affect the absorption of ingredients into your skin. The US Environmental Protection Agency (EPA) has even noted “there is no dermal absorption of the EDTA salts” for adults, children, or infants (US EPA).
The only safety concerns for disodium EDTA arise when you eat it. Oral exposures have been shown to cause reproductive and developmental effects, but not dermal exposures. Sometimes people get confused by this – how can something be safe to put on your skin if it is poison when you eat it? The answer is simple: Often, what is good for the skin is bad for the digestive tract, and vice versa. For instance, healthy skin tends to have a low-normal pH, to maintain the skin’s natural acid mantle. Healthy digestive tracts tend to have very low pH levels, somewhere around a pH of 2. But you want to eat alkaline and use acidic products. Why? The skin of healthy persons is broken down at high alkaline pH levels, but it is better to eat high alkaline pH foods, to counterbalance the acidity in the system. What’s more, some of the best drugs for skin conditions like psoriasis, rosacea, and even skin cancer are poisonous when ingested. Drugs that are ingested orally are designed to enter the bloodstream quickly and in higher quantities, whereas drugs that are designed for topical application are designed to enter the bloodstream slowly. If you use a product with disodium EDTA, you will not get a lethal or toxic dose into your bloodstream, unless you use 1500x the typical dose within a single day.
What are Some Products That Contain Disodium EDTA?
Green Cream – High Potency Retinol (Full post)
Olay Regenerist 14 Day Intervention (Full post)
Bottom Line
Disodium EDTA takes the hard ions out of your water so that your skin is left softer. Disodium EDTA also takes hard ions out of the rest of the solution, so your products keep for longer.
Despite what other websites might tell you, disodium EDTA is not a penetration enhancer (US EPA). Disodium EDTA is safe for topical application up to 1500x the typical dose per day in the average skin care or cosmetics product. It is not safe to ingest, however, but this is OK – keep in mind that food is not skin care! One example: Acidic pH substances are great for the skin but bad to eat, and alkaline pH substances are great to eat but bad for the skin.
As far as products with disodium EDTA go, we say, they’re perfectly fine, and you may even notice slightly softer skin afterwards! We personally like Olay Regenerist 14 Day Intervention (Full post).