I now make a simple foaming handwash using only two ingredients: water and castile soap.

By switching to a simple homemade handwash, you can reduce exposure to unnecessary chemicals, minimise waste and save money.  

The liquid soaps you  find in the supermarket are laden with a long list of unnecessary and nasty chemicals. I used the helpful Skin Deep cosmetics database (found at ewg.org/skindeep) to investigate the safety of ingredients in a major brand of anti-bacterial handwash. I discovered that of the 17 ingredients listed, seven are considered a ‘‘moderate hazard’’, including the first ingredient after water – cetrimonium chloride.

This chemical and others, such as methylchloroisothiazolinone and methylisothiazolinone, can cause skin damage and allergic reactions. Simply switching to a ‘‘natural’’ product isn’t the answer. Just because something is advertised as containing ‘‘ingredients of natural origin’’ doesn’t mean that it’s safe to put on your skin.

Even an expensive hand wash marketed as ‘‘plant-based’’ and containing ‘‘all-natural ingredients’’ contains potentially irritant chemicals such as cocamidopropyl betaine, phenoxyethanol and phenoxyethanol. 

The home brand and budget hand soaps fare even worse, with most containing the ‘‘high hazard’’ triclosan, despite it being a toxic chemical that can interfere with hormone regulation. 

There’s no evidence that including triclosan and other antibacterial or antimicrobial ingredients in hand soaps is any more effective than plain soap and water. 

Given that washing our hands with plain soap and water works just as well, washing our hands with these chemicals seems an unnecessary risk, particularly for children. But I get the appeal of liquid soap. Thankfully it’s easy to make your own. 

To make your own foaming hand soap, you will need a foaming soap dispenser. You can buy foamy bottles from online soap-making supply stores, or you can simply buy a foaming hand soap and reuse the dispenser. 

Castile soap is a very mild liquid soap that will clean your skin without stripping it of natural oils. It is traditionally made using pure olive oil, but can also be made with other oils.

You will find it in most organic food stores, or from online soap supply stores. 

To make the foaming hand wash, fill the dispenser with around four parts sterilised water and one part castile soap.

I simply leave the morning kettle boil for an extra minute and use that water once it has cooled. 

Buying your castile soap in bulk will make your hand wash super-frugal. I bought a five-litre bottle – which is enough soap for me to make 25litres of handwash. I like that I haven’t had to think about buying hand soap in the five years since I bought the bottle.

I’m guessing it will last me another five years. My foaming handwash works out costing around $1 a litre – far cheaper than even the cheapest and nastiest home brand refill hand soap at $4a litre.

 The pump can become stiff after a while. I’ve read that you can add a dash of oil to your mix to alleviate this problem.

I simply wash my dispensers thoroughly in sterilised water and leave them to air-dry when this happens.

Switching your handwash may seem a  trivial change that isn’t worth the bother. But lots of small changes can make a  big difference.

Tricia shares tips for living better with less at littleecofootprints.com and on Instagram (TriciaEco)