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What Is Formaldehyde in Shampoo? | A Detailed Guide

Formaldehyde is listed by the WHO as a Group 1 cancer causing agent, so people are often concerned to find out that it exists in shampoo. Many people ask, “What is formaldehyde in shampoo?” They wonder if it’s the same substance. We’ll explain below.

What Is Formaldehyde in Shampoo?

Formaldehyde is a gas that is known as a carcinogen. The important thing to remember is that it’s on the same WHO cancer list as hot dogs, sunshine, ham, and other items. Formaldehyde isn’t added to shampoo; it’s released by preservative compounds.

The small amount of formaldehyde that is released destroys contaminants so that your shampoo lasts. It’s safe in these amounts. You may want to understand more about formaldehyde and its effects on shampoo and people.

Many people have questions, including:

  • What is formaldehyde?
  • What does it do in shampoo?
  • What are the risks?
  • How do I know if my shampoo contains formaldehyde releasers?

We had the same questions, so we searched for the answers. Is this one of the important shampoo ingredients to avoid? Continue reading to learn all about formaldehyde and what it does in shampoo.

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What Is Formaldehyde?

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Formaldehyde is a gas, and all living things produce it as part of cell metabolism. In shampoos, there are preservatives that release formaldehyde, which kills microorganisms and prevents the growth of bacteria.

This is how manufacturers extend the shelf life of shampoos and other products. Without it, the shampoo could go bad in less than two weeks. The WHO lists formaldehyde as a Group 1 carcinogen. However, other items on the same list include sunshine, alcohol, hot dogs, and ham.

Formaldehyde is found in vegetables, apples, pears, meat, coffee, and more. Although formaldehyde can be harmful to people in high amounts, the amount in these foods and shampoos is small enough that it’s considered safe. 

What Does Formaldehyde Do in Shampoo?

Formaldehyde isn’t actually added to shampoos. It’s released by some of the preservatives in shampoo. This is how manufacturers ensure that the shampoo lasts long enough to get to the store, to your home, and be there for you to use. 

Formaldehyde can pose a threat to people in certain occupations, such as embalmers and pathologists. They breathe in larger amounts of formaldehyde.

The tiny amount that is released in shampoo does more good than harm because it prevents bacteria and mold from growing. The amount released is chemically the same as what is produced naturally in animals and people. 

What Are the Risks of Formaldehyde in Shampoo?

There are some health concerns associated with formaldehyde. It’s a known carcinogen, and when you use shampoo, you are exposed to it through your skin or from the gasses in the product.

The formaldehyde released from preservatives in shampoo has been linked to cancer, but there isn’t any evidence that it causes cancer. Another risk is skin irritation. It can cause irritation on the scalp and skin for people who are allergic to it or who have sensitivity to it.

It’s allowed in shampoos in the United States and the EU, but it’s banned in cosmetics and toiletries in Japan and Sweden. Although there are some risks, formaldehyde in these small levels is considered safe for most people. 

How to Tell If Your Shampoo Contains Formaldehyde Releasers

Most shampoos contain the preservatives that release formaldehyde. There are more than 40 different formaldehyde releasers, but some of the most common in shampoos include the following:

  • Quaternium-15
  • DMDM Hydantoin
  • Ureas, such as imidazolidinyl or diazolidnyl
  • Benzyl Hemiformal
  • Formalin
  • Formic aldehyde
  • Methylene glycol
  • Methanal
  • Methylene oxide
  • Methane diol
  • Paraform
  • Oxymethylene
  • Glyoxal
  • Timonacic acid

When you look at the ingredients list, the formaldehyde releaser will normally be one of the last ingredients. Most shampoos will contain them, but there are some alternatives. The reason that they’re still used in shampoos is that they do a great job of killing dangerous substances such as mold and bacteria. 

Frequently Asked Questions

What exactly are formaldehyde releasers?

Formaldehyde releasers are preservatives that release formaldehyde. There are more than 40 of them, and they have different ways of working.

One type is synthesized from formaldehyde, and the second is a chemical that decomposes to produce formaldehyde. They extend the shelf life of the shampoo.

Does baby shampoo have formaldehyde?

Many baby shampoos do contain preservatives that release formaldehyde, but the amount is less than that in a pear that is medium sized. It’s considered safe to use because the amount is so small. 

How does formaldehyde extend the shelf life of shampoo?

Shampoos contain formaldehyde releasers that release tiny amounts of formaldehyde over time. This kills microorganisms, prevents the growth of bacteria, fungi, yeast, and other contaminants.

As a result, the shampoo is safe to use for a longer period of time. If the shampoo didn’t have these preservatives, it would last for less than two weeks.

Read Next: Does Shampoo Ever Expire?

Does formaldehyde cause cancer?

Although formaldehyde is a known carcinogen, inhaled formaldehyde is linked to cancer only when there has been a significant and prolonged exposure.

Formaldehyde is quickly and easily broken down, often before it can do significant harm. Scientific studies have shown that formaldehyde is metabolized quickly before it has a chance to get into your tissues and cause cancer. 

Is formaldehyde dangerous?

The small amount of formaldehyde that is released by the preservatives in shampoo is so tiny that it isn’t considered dangerous. In fact, there are many cases where using a synthetic ingredient can be more risky. Some products don’t disclose their ingredients, so you don’t know what they contain. 

So, What Is Formaldehyde in Shampoo?

In shampoo, manufacturers include preservatives that are formaldehyde releasers. It worries some people because formaldehyde is a known carcinogen. However, every living thing on the planet releases formaldehyde.

Vegetables, fruits, and other foods release formaldehyde, but it isn’t dangerous because they release such small levels. It’s important because it allows your shampoo to last long enough that you can use it. Otherwise, it would last less than two weeks.