Do conventional shampoos have an impact on the environment?

environmental impact of conventional shampoos

The people who lived before the 20th century found it incredibly hard to believe that anything human beings do could ever impact on the environment. The skies seemed too infinite, the oceans too vast and the multitudes of animals too resilient to ever be affected by little old us. Now of course we know better (cough cough). Powerful philanthropists like Al Gore and Leonardo Dicaprio have informed us about the ways in which our use of fossil fuels is pushing us towards a doomsday that will make the ending of Titanic look like a Pixar movie.

And yes, even shampoos make it onto the “no buy” list because of some of the harsh chemicals found inside their plastic bottles. The offending ingredients are the detergents which are responsible for their cleaning properties. The environment is impacted when these detergents go down the drain and onto the heads of innocent ninja turtles. Let us take a moment to count the many sins of these products.

Cry me a river

Detergents are comprised of a lot of phosphates and nitrates which can be harmful if they reach our rivers. These nutrients enable accelerated growth of aquatic plants (like algae) and in so doing threaten to overrun the aquatic ecosystem. When these plants die, large amounts of oxygen are extracted from the water during the decomposition process. This has the knock-on effect that fish and invertebrates in the water may be starved of oxygen, ultimately resulting in their asphyxiation. This matter doesn’t stop decomposing though — but now it has to do so without oxygen. Once that point is reached then hydrogen sulphide is released into the water, leaving a putrid “rotten eggs” smell in the air.


Detergents are made up of surfactants which are essentially chemical agents that diminish the surface tension of oil and water. This property is hazardous to aquatic life, according to the U.S. Environmental Protection Agency, in that surfactants weaken the mucus layer around fish that protects them from parasites and bacteria. The reduction in surface tension in the water also increases the likelihood that the aquatic life could absorb pesticides, phenols and other harmful substances flowing into the river. Eventually this reduces breeding rates.

Biodegradable surfactants to the rescue …. sort of

Many manufacturers have thankfully decided to move away from undesirable surfactants in their products, opting instead for biodegradable versions. The question is: Are these detergents much better for the environment?

To answer that question one has to keep in mind that biodegradability is measured in 28 day cycles. The problem is that molecules have plenty of time within that window to escape from sewage treatment facilities and spread into the environment, possibly giving rise to the algae bloom described above. Also, some surfactants are highly attracted to limestone and will tend to settle at the bottom of rivers. Caked in sediment, it becomes more difficult for them to break down.

Furthermore, some of the other standards of biodegradability are less than convincing. For one, currently it is only required that 60 percent of the product degrades within 28 days. And even if 100 percent were accounted for, there would still be the problem of testing. A lot of the inspections are done in laboratories — under very different conditions to those that exist in the environment. The temperature, salt content and biological activity can all vary greatly out in the field such that it is hard to trust fully in test results.

Bottom line

Though several studies have shown that surfactants are not overtly hazardous to the environment when regulations are strictly followed, there are many reasons to be dubious of choosing surfactant-based shampoos. Plant-based alternatives are surfactant free and avoid many of the risks described above. Also, the ninja turtles will thank you for your contribution to a healthier sewer.

Photo by Jackson Jost on Unsplash

What is the detergent in soap nuts and how does it work?

What is the soap in Soap Nuts? Soap Bubble Image

Here at PureRescue we believe that plant-based shampoos are better for your hair because they avoid some of the nasty chemicals found in cheap alternatives. They also clean just as well, if not better, than their commercial counterparts. The reason these plant-based shampoos can outclass products made by big chemical companies is because of one or two incredible plants that have soap-like properties. The most prominent and widely-used of them all is appropriately named the soap nut.

The soap nut has enriched countless generations through its ability to clean clothes, bodies and hair. But what is it about this nut that makes it such a good cleanser, if at all?

The science

First of all, we have a little confession to make: The soap nut isn’t actually a nut, it’s a berry. To be fair, this is not a naming scandal, it just that when the small black berry, approximately one inch (2-2.5 cm) in diameter, hardens it ends up looking a lot like a nut. The berry, which grows on the sapindus mukorossi tree in the Himalayas, is deseeded and dried before being used. It contains a natural soap called saponin which functions like a surfactant — i.e. the chemical that binds both with oil and water. Like all surfactants, saponin reduces the surface tension of water, making it easier to get into the fibres your hair to dislodge dirt. When this process is combined with the vigorous movement of your hand, the grime can be rinsed away.

In contrast to commercial shampoos, products containing soap nut do not foam. This can be a little confusing for some consumers because modern marketing has created a strong link in our minds between froth and cleanliness. This is simply not true however — low-foam shampoos have been shown to get rid of grime and grease as well as foamy competitors.

The sustainability

First of all the soap nuts are wild-harvested. They are picked from trees without the use of chemicals, fertilizers and pesticides. That is the fortuitous consequence of the fact that most insects don’t like the taste of saponin. Soap nuts also require very little processing and packaging which means they score really well when it comes to sustainability.

This is no small accomplishment. A carbon footprint study done by Boots in 2008 found that the “raw material extraction” phase was the second biggest contributor to greenhouse gas emissions in the shampoo production process. It contributed approximately 85g of CO2 per 23,5g bottle of shampoo. Because the soap nut eliminates many of the production steps, it allows the environment to breathe just that little bit easier.


Given that the soap nut isn’t actually a nut, even consumers with nut allergies can use it without any apprehension. Soap nuts are naturally hypoallergenic, odorless and particularly gentle on your hair. They are so soft in fact that when soap nuts are used as detergents in washing powders, there is no need for fabric softeners.

A word on aloe vera

Besides the soap nut, aloe vera is also a common addition to plant-based shampoos that deserves a mention here as well. Like its berry counterpart, aloe has a multitude of impressive cleaning properties. These arise primarily from the fact that aloe has a similar chemical composition to keratin — the protein that hair is made of. This means that it is great at rebuilding hair fibres and that it can penetrate the entire length of the hair shaft to repair it.

Aloe also contains 20 amino acids which form the building blocks of the hair and cells in the scalp. Add to that the conditioning properties inherent in aloe and you have an all-round nourishing experience that leaves your hair with a healthy glow.

Photo: Photo by Markus Spiske on Unsplash