And this is what shampoo does to that dirt.

Surfactants form these micelles around the dirt, which is what grabs onto dirt and oil.

It's like, "No, no, I don't wanna go."

That was the dirt screaming for its life.

Erica Douglas has been a cosmetic chemist for more than a decade,

and today she's going to break down the ingredients in Head & Shoulders Classic Clean dandruff shampoo.

It's about to get messy.

It's actually a fairly simple formula. Not a lot of ingredients.

That means that there's not a lot of fluff in this formula.

Erica broke down the ingredients into these categories.

Let's start here.

One of the first ingredients that I see is pyrithione zinc.

This is one of the most common actives used in the cosmetic space to fight dandruff.

Without this ingredient, it's just the shampoo.

Dandruff is actually caused by a fungus called Malassezia, and it feeds on the oil.

The FDA allows up to 2% of pyrithione zinc in products like this shampoo, which are applied and then rinsed off.

The Classic Clean formula uses pyrithione zinc at 1%.

But in the EU.

They actually banned pyrithione zinc from being used as a cosmetic active.

According to the company, the EU version uses this ingredient instead of pyrithione zinc.

So the active ingredient handles the dandruff, but surfactants like these sulfates are what actually clean the scalp.

Surfactants are the soapy part of the shampoo.

It's what causes the suds, it's actually what is pulling the dirt and the oil off of your hair and scalp.

I believe that they are using this as their primary surfactant, and the cocamidopropyl betaine is the secondary surfactant in this formula.

Surfactants work a little something like this.

We're gonna just use some regular pepper, have it float on top of some normal deionized water.

These surfactants have their hydrophilic head and their hydrophobic tails, and so they form these micelles around the dirt, which is what grabs onto dirt and oil, and helps it to remove it from the hair and the scalp.

Instantly you see how it repels it.

It's like running from the shampoo.

Some surfactants create more suds than others, but...

Foam actually doesn't dictate how well a shampoo is cleaning your hair.

There are certain surfactants that can produce a lot of foam, like this one,

but then there are other surfactants that are more mild.

Does not mean that it's not working.

So foam is kind of like for aesthetics.

And we call this the cylinder shake method.

You can see how much foam is going to last, and how it separates out.

A lot of hairstylists view sulfates as being too harsh.

I see sulfates as a great surfactant when used in moderation, and they're also being formulated in conjunction with other conditioning agents that allow it to moisturize and condition the hair at the same time.

That's the job of this ingredient here, otherwise known as a silicone.

They help to maintain the water level in your hair.

This is water with just a little bit of Violet 1 colorant, versus when I do the same thing with dimethicone.

And dimethicone just has a little bit of the Blue 1 colorant.

You notice how the water went right through the sponge.

That's because it soaked in and went straight to the bottom, versus this silicone stain right on top.

This is the difference between when your hair is absorbing moisture, versus using a silicone like dimethicone to help seal the cuticle and maintain moisture content.

Silicones have really gotten this bad rep.

They've been thought to weigh the hair down or leave a buildup.

This is absolutely not true.

They have the ability to stay on the hair, to seal the cuticles, and they do come off the hair when using a shampoo.

Now, for what gives the shampoo it's distinct look.

So Head & Shoulders uses Blue 1 and Red 33 as their colorants, and that's how you get this really cool light blue looking color.

In addition to the glycol distearate, which is used as a pearlizing agent to give it that pearl look.

I don't know what the ratios are that they use.

That's their proprietary information.

First, I'm gonna start with my blue number one.

Okay, and then we'll try to see what happens when we add a little Red 33.

As you can see, I literally put less than a gram in, and that's how dark it got.

Blue 1 and Red 33 are both synthetic colors approved for use in cosmetics with some use restrictions.

Some of the concerns that come around synthetic color would be that it could potentially be an irritant or an allergen for some people.

According to the environmental working group, Safety Ratings, Blue 1 is marked as high hazard while Red 33 is marked as moderate.

A Head & Shoulders representative reiterated that these dyes are FDA approved, noting that the Classic Clean formula is known for its signature blue color.

And when it comes to fragrance.

It just lists that they use fragrance. Nothing else.

Fragrance contains 30, 40 ingredients sometimes.

The ingredients that make up a fragrance are often proprietary.

But according to Erica's scientific sniffer.

Product has floral and aquatic notes.

While it's not listed on the label, Head & Shoulders does list over 20 ingredients found in the Classic Clean fragrance formulation online, including some considered allergens in the EU.

And soon, this could become a more common practice.

A new law was put into action which actually will now require cosmetic products to list fragrance allergens on the label going into 2024.

Consistency is also a crucial part of a shampoo's formulation.

Some of the ingredients that they're using to give that thick, creamy feel is glycol distearate, also the guar hydroxypropyl trimonium chloride.

Guar is a great conditioning detangling agent, but it also gives the formula some thickness.

With salt can give you that thick feel.

And while the final product feels thick.

The most surprising thing about shampoo formulations is that it's mostly water.

Any product that has water in it has the potential to grow mold, fungus, bacteria.

Ugh, we don't want any of that stuff.

Different packages The Wall Street Journal purchased had different preservatives listed.

The preservative used in this product is sodium benzoate.

Another version of the same product lists these two additional preservatives, which have a high incidence with skin allergies.

The company said it recently shifted away from this preservative combination to one with sodium benzoate.

But products with the combination are still currently sold on store shelves.

Before a product hits the shelf, one crucial element must be tested. That's the pH.

We are measuring a pH of 7.3 for this Head & Shoulders product.

This is not abnormal, but it is on the high end of what I would normally see.

Head & Shoulders said this reading is in line with the standard range of its formulas, which it said remains America's number one anti-dandruff shampoo with moisture levels as they are.

And there are few things to note on the overall packaging.

They claim that this bottle is paraben free.

I would agree that this is a paraben free product.

The paraben issue is a very provocative topic.

There have been some preliminary studies that show that there could be possible linkage between parabens and cancer.

There's no conclusive scientific data that links paraben usage and cosmetics directly to cancer,

but the possibilities of it being a carcinogen has provoked some limitations on how this ingredient is being used in the cosmetic space.

And Erica sees some opportunities for improvements.

If I could change anything about this formula, I would probably add a few more conditioning and moisturizing agents just to give more functionality and more control to the actual hair.

I think that dandruff is a little hush hush because nobody wants to be known as the snowflake.

I think a lot of people associate dandruff with being unclean, but that's completely not true.

We need to talk more about it.