Why Is Shampoo Bad For The Environment And What Can You Do?

Many of us wash our hair on a daily basis. But have you ever wondered what impact the shampoo you wash down the drain has on our environment?

The truth is that most of the products we use daily, including shampoo, have a profound environmental impact. So if you want to live a more sustainable life, it’s worth looking into how the things you use can harm the planet.

I have been researching this topic for quite a while now, and I’m always surprised how badly most of the things we routinely do impact so negatively on our environment.

While it might feel a bit depressing sometimes, knowing why something is bad also allows us to make changes that will reduce its impact.

So why is shampoo bad for the environment? In this article, I share with you what I have learned, and we will also look at what we can all do.

How Is Shampoo Bad For The Environment?

There are three reasons why commonly used liquid shampoos have a negative environmental impact.

1. Waste of water
2. Ingredients
3. Packaging

I will look at each of these reasons in more detail, so we can all understand where changes are necessary.

Liquid Shampoos Waste Water

The vast majority of shampoos that you can buy in the UK in supermarkets or health and beauty retailers come in liquid form. Although this is changing, with more shampoo bars becoming available.

When you look at the ingredient list of your liquid shampoo, the first one you will see is “aqua”. That’s water to you and me. Depending on the formula, shampoo in liquid form can contain anywhere between 75% and 95% of water.

But this is a huge waste, because we all have water at home. And it’s perfectly possible to have shampoos in a concentrated form, without water, such as powders or bars.

Water is such an important resource, without it life isn’t possible. Everything on this planet needs water to live, including us humans. A report by the UN estimates that by 2030 there will be a 40% freshwater shortfall.

And mismanagement of water is to blame, so the UN report. We have damaged the balance of the global water cycle.

Water scarcity, which is where we seem to be heading, will also mean a loss of biodiversity, because there is less water to support all the creatures that live on our planet.

So why do we continue to make liquid shampoos, or cleaning products, or laundry detergents, for that matter? Imagine the amount of water we could save if we only used such products in the form of concentrates?

But that’s not all. Water is heavy, with a litre of water weighing one kilogram. Transporting shampoo bottles that are mostly water uses up more energy, which means a larger carbon footprint.

But they are also bigger, so you can transport fewer at a time, which means you need more lorries or boats. Again, this increases the carbon emissions associated with the transportation of goods.

The solution: products in concentrated form, where we add the necessary water at home. Shampoo bars are a great, concentrated alternative to liquid shampoo.

Many Shampoo Ingredients Harm The Environment

Another reason most conventional shampoos are bad for the environment is the ingredients they contain. Firstly, the vast majority of shampoo ingredients today are made from petroleum, so-called petrochemicals.

Fossil fuels aren’t a sustainable source material, as there is only a limited amount available. And scientists have made it very clear that we have to keep fossil fuels in the ground if we want to avert a climate catastrophe. (Rayner 2020)

Secondly, producing these synthetic materials is also very energy-intensive, which means it produces a huge amount of carbon emissions.

It’s estimated that the chemistry industry is responsible for about 2 billion metric tons of carbon dioxide per year, a potent greenhouse gas. That’s 5% of all emissions worldwide. (Gabrielli et al., 2023)

Thirdly, although many surfactants are biodegradable, so many are used daily that huge amounts get into our environment, where they are harmful to aquatic life. The various ingredients reach our waterways through the wastewater system, which isn’t able to filter them out completely.

Once in an aquatic ecosystem, these harmful chemicals interact with the marine life and negatively impact it. Let’s look at the worst ingredients in more detail.

Shampoo Ingredients To Avoid

Different shampoos have different formulations, but there are some common ingredients that are used in most of them.

Sodium Lauryl Sulfate (SLS)

This ingredient is an anionic surfactant that is used in many personal care as well as cleaning products. It’s basically the main ingredient, as it removes dirt from your hair.

It can be derived naturally or made in the lab. The source material can be plant-based, or it can be made from petroleum. (Bondi et al., 2015)

Unless the manufacturer clearly states how the SLS used in their product is made and from what source material it’s impossible to tell from the ingredients list.

However, we know that synthetic chemicals made from petroleum tend to be cheaper than plant-based and naturally derived alternatives. So the chances are, most shampoos will contain SLS, made synthetically from petroleum.

This in itself is bad news for our environment, as we have already said. However, there is more bad news because of the impact SLS can have on aquatic life.

Various studies have looked at the effect of this particular surfactant on aquatic as well as terrestrial ecosystems. And many have found that it is toxic to different marine organisms even at lower quantities. (Asio et al., 2023)

So it’s best to avoid any shampoos or any other products containing this ingredient.

Sodium Laureth Sulfate (SLES)

This surfactant is made from SLS and is said to be milder and kinder to skin. That’s why it’s often used instead of SLS. However, as it’s made from this chemical, there are some of the same issues.

It’s likely that most SLES used in conventional shampoos is made from SLS that has been made in a lab from petroleum.

Sodium Laureth Sulfate has been studied less than SLS, but one study has shown that it’s toxic to the Tubifex worm, an invertebrate that lives in the sediments of lakes and rivers.

Even non-toxic levels have had an impact on this worm, including erratic behaviour and mucus secretion. The study concluded that SLES is a toxic chemical that can cause a lot of harm. (Bhattacharya et al., 2021)

So while this surfactant might be better for us, it still poses a risk to our environment.

Preservatives

Most products we use contain preservatives, which extend their shelf life. They prevent the growth of fungi and bacteria, which can make the product unsafe.

It has to be said that preservatives are only necessary in products in liquid form, such as liquid shampoos. That’s because fungi and bacteria need moisture to grow. (Qiu et al., 2022)

Different manufacturers will use different preservatives, but there are some common ones that are often used in shampoos that you can buy here in the UK.

Parabens are probably the most commonly known, mostly because they have been in the press for not being good for us. And what’s bad for us generally is also bad for the environment.

This group of preservatives works by stopping bacteria’s ability to transport nutrients, which they need to survive. (Vindenes et al., 2022)

That’s all well in the shampoo bottle, but once the shampoo has been used and goes down the drain, the parabens can reach our waterways, as they aren’t fully removed during water treatment processes.

Studies have shown that parabens have a profound impact on microbial ecosystems they become part of. They can increase antibiotic resistance in bacteria, which can destroy the balance of the ecosystem. (Pereira et al., 2024)

Other studies have found that parabens can harm aquatic organisms, including zebrafish, shrimp, and algae. (Dailianis et al., 2023)

Because parabens have had quite a bit of bad press, many manufacturers don’t use them any more. But still check the ingredient list for any ingredient that ends in -paraben.

Sodium Benzoate, however, is still used in many liquid shampoos you can buy here in the UK.

Studies have shown that this chemical changes the pH level of aquatic ecosystems exposed to it. This can lead to a reduction of available nutrients, which means that the marine organisms have less food to eat. (Hu et al., 2024)

Related to this preservative is another, Benzyl Alcohol, which is used in shampoos you can buy here. A study has shown that it stunts the development of zebrafish and reduces their survival rate. (Manjunatha et al., 2020)

Another preservative you might spot on the ingredient list of your liquid shampoo is Methylisothiazolinone. Studies have shown it can harm zebrafish embryos and Thale Cress, a plant from the mustard family. (Lee et al., 2021; You et al., 2024)

You’re also likely to find Phenoxyethanol on the list, another preservative often used. While it hasn’t been studied much yet, one study has shown that its presence negatively affects zebrafish (Goldstein, 2020)

Synthetic Fragrances

Most shampoos have a lovely, strong scent that makes your hair smell nice for days. This is achieved by adding synthetic fragrances to the shampoo.

These are some of the most harmful chemicals for our environment and us. Because fragrance formulations are classed as a trade secret, all it will say on the ingredient list is perfume or fragrance.

You won’t know if the fragrance used to create the nice scent comes from synthetic or natural sources, like essential oils, unless the label clearly states this.

However, the vast majority of common shampoo brands you can buy in the UK use synthetic fragrances because they are cheap and easy to get. They are made from petroleum, like many other commonly used ingredients.

You can find out more about these artificial scents and how they affect our environment in my article about synthetic fragrances.

Emulsifiers

In a liquid shampoo, you need ingredients that make sure that the other ingredients are blended together well. These are called emulsifiers.

While there are many different ones, two are most often used in shampoos: Diethanolamine (DEA) and Triethanolamine (TEA).

Both these emulsifiers also help to adjust the pH level of the shampoo and act as fragrances. But they are also toxic to aquatic life.

Despite their biodegradability, these chemicals have been shown to be toxic to marine organisms, even in low concentrations. (Libralato et al., 2009)

Another emulsifier is Cocamide MEA, which belongs to the same chemical group as the above two ingredients.

There is evidence of its acute toxicity to aquatic life, according to the EWG.

With all these nasty ingredients, do you still have to ask why is shampoo bad for the environment? And we haven’t even finished yet.

Silicones

These are a group of compounds that are used in many cosmetic products because they have useful abilities, including as moisturisers, emulsifiers, and film formers. In shampoos, they can make your hair look healthier, although this effect tends to be temporary. (Ivanova et al., 2024)

Their use is widespread, and many consider them safe for the environment. However, there is some dispute over this, with some studies arguing that the commonly used silicones in cosmetics bioaccumulate and are toxic to aquatic ecosystems. (Bilal et al., 2020)

There is another reason why silicones aren’t eco-friendly, and that’s because they are made from petroleum. Again, not a sustainable source.

To know if your shampoo contains silicones, check the ingredient list for words ending with -cone or -xane. This is an indicator that it’s a silicone, which is also called siloxane.

Polyquaternium

This type of ingredient is used as an anti-static ingredient to keep hair from becoming statically charged. There are various different versions, but the one I have seen most often on labels of shampoos available in the UK is Polyquaternium-7.

This ingredient is known to be toxic to the environment, and the EWG allows it only with certain restrictions.

Studies have shown that polyquaterniums can impair aquatic organisms exposed to them (Brill et al., 2024). One study has shown they can harm zebrafish larvae. (Hansen et al,. 2023)

Polyethylene Glycol/ PEGs

These synthetic chemicals are used to get the right consistency in shampoos, but also as emulsifiers and solubilisers. Basically, they make sure your shampoo is a thick cream.

Although PEGs are considered safe, there are studies that have shown that exposure to these chemicals can cause harm.

One study found that if PEGs were present in the water, frog eggs hatched later than normal, and malformations were more likely. (Zicarelli et al., 2024)

On ingredient lists, these chemicals either have the prefix PEG or words ending in -eth.

Ethylenediaminetetraacetic Acid/EDTA

This ingredient is used to remove mineral and chemical build-up from your hair. So it’s used to make sure your hair is clean.

While there isn’t that much research out there regarding the impact of EDTA on our environment, one study found that it was harmful to green algae. (Kim et al., 2023)

EDTA is also made from petroleum, like so many other commonly used ingredients.

This isn’t an exhaustive list, as different shampoo manufacturers use different ingredients. But they are commonly used and are bad news for our environment.

Liquid Shampoos Come In Plastic Bottles

Finally, liquid shampoos also contribute to the increased use of plastic. While plastic is a highly versatile and useful material, it’s not environmentally friendly.

According to the Centre for International Environmental Law, 99% of plastic is made from fossil fuels. Plastic production and disposal generates large amounts of carbon emissions, and the plastic industry could be responsible for 19% of greenhouse gas emissions by 2040.

So the message here is clear: we have to reduce the amount of plastic we produce. Too many things are made of plastic, including packaging.

And although plastic bottles for liquid shampoos can be recycled, this isn’t the solution. We can’t recycle our way out of this plastic crisis.

For one, plastic can only be recycled 2-3 times before it’s degraded too much to still be used. But recycled plastic is also of lower quality. So often a mix of recycled plastic and new plastic (so-called virgin plastic) is used.

And did you know that only 9% of plastic is recycled every year globally? So even plastic that might be recyclable isn’t necessarily recycled.

We have to reduce the amount of plastic we use, and shampoo bottles are an area where we can easily do this.

Switch To Natural Shampoo Bars

The answer to our question of how is shampoo bad for the environment is quite complex. But there is quite an easy solution for us consumers.

We can switch to using natural shampoo bars and solve all three issues:

• Shampoo bars are concentrated and don’t contain water – so no wasting water or needing perservatives
• Natural solid shampoos don’t contain nasty chemicals – instead plant-based and biodegradable ingredients are used
• Solid shampoos are plastic free – they don’t come in plastic packaging

The same is true for many other personal care products, too, such as soap/body bars, conditioner bars, deodorants, and many more.

I have tried several shampoo bars and compared them in my Best Shampoo Bars article for you to find the one that is right for you.

Make the switch to reduce the impact your shampoo has on our environment.

Best Eco-Friendly Shampoo Bars In The UK

Shampoo Bar	Value For Money	Range	Results	My Rating	Full Review	Official Website
	Excellent	Great	Outstanding	4.90	Read Review	Visit Website
	Outstanding	Good	Excellent	4.90	Read Review	Visit Website
	Excellent	Great	Outstanding	4.90	Read Review	Visit Website
	Great	Outstanding	Excellent	4.85	Read Review	Visit Website
	Excellent	Limited	Outstanding	4.80	Read Review	Visit Website
	Good	Excellent	Excellent	4.75	Read Review	Visit Website
	Great	Good	Excellent	4.70	Read Review	Visit Website