Are All Sulfates Bad?

A while ago I noticed a natural-looking brand of shampoo in the shower.

My wife had picked it up but wasn’t using it, so I decided to give it a try.

The bottle boasted several signs that it was a clean, ethical product: 100% recycled plastic, 100% vegetarian, logos from organizations that protect animals from cruel testing, claims of no toxic ingredients such as parabens and phthalates.

But then I saw some confusing phrases: “no harsh sulfates,” “no damaging sulfates.”

Since I started working at Public Goods, I’ve become familiar with sulfates, chemical compounds that increase the cleaning power of shampoos and cleaning products. This cheap but reliable ingredient helps create the foamy lather effect many of us associate with the experience of bathing or cleaning.

Sulfates often support the petroleum industry, which is responsible for much of the pollution that contributes to climate change. During the manufacturing of products that contain sulfates, there is a risk of contamination from 1,4-dioxane, a chemical the Environmental Working Group [EWG] believes might be linked to cancer in humans. Some consumers simply find sulfates irritating to their skin or eyes.

Because of these facts, I assumed all sulfates were at least somewhat unhealthy. The idea of sulfates that weren’t harsh or damaging seemed like an oxymoron.

Then I remembered that people frequently use the term, “sulfates,” to refer specifically to sodium lauryl sulfates [SLS] and sodium laureth sulfates [SLES]. These compounds are by far the most controversial in the sulfate category.

“Sulfate-free” shampoos don’t contain SLS or SLES, but most of them do rely on some form of sulfate, according to Lizzy Trelstad, a chemist at Beaker. There is no regulation of the term, “sulfate-free,” so brands can employ it however they want.

When I perused the ingredients on the back of the bottle, I didn’t see any SLS or SLES. I did, however, notice sodium sulfate and sodium lauryl sulfoacetate [SLSA]. These chemicals may technically be sulfates, Trelstad said, but it’s true that they aren’t harsh or damaging like SLS and SLES.

EWG has assigned sodium sulfate and SLSA a hazard score of 1 out of 10, meaning the organization doesn’t view the substances as public health concerns. Unlike SLS, there is no reported risk of contaminating these chemicals during their manufacturing process.

SLSA has become a popular ingredient in shampoos that claim to be natural. Nonetheless, the compound can be synthetically produced, Trelstad said, citing her experience working with natural and synthetic personal care brands.

These revelations compelled me to reevaluate my perception of sulfates and sulfate-free products, especially shampoos. Sometimes consumers, including myself, can be a little dogmatic about the ingredient.

When I first read the “no harsh sulfates” label, I assumed it was marketing language designed to obfuscate alarming ingredients. Now that I have thought more about the issue, the phrase might have simply been a poor choice of words.

If I was leading the brand, I would highlight the fact that the products don’t include SLS or SLES. Instead the vague language raised questions and made me nervous about the product. The case may seem personal, but many of our members at Public Goods have a similar mindset and often research ingredients or marketing buzzwords.

Brands can use mild sulfates and still be ethical, but perhaps what’s equally important is being direct and transparent with consumers. When healthy products have nothing to hide, there’s no need for confusing claims.