17 natural insect repellants in home made soap making: As proven by science

The past few weeks I’ve had a new problem which I’ve never had to deal with in my life before. I don’t know if it’s because I’m heavily pregnant (do the hormones change the way I smell?) or if the wasps in Donegal are just more persistent than the rest of the world, but I keep getting them showing way too much interest in me.

I actually got stung by a bee for the first time in my life last week! I was stuck at some roadworks and a bee flew between my dress and the car seat. I had no idea it was there, so when I leaned back to wait for the line to move, it stung me! Usually, insects avoid me. So I started wondering about natural insect repellants.

Being a scientist at heart, I couldn’t just buy any random essential oil rumored to work as a natural insect repellant, so in this article I’m going to give you an overview of the scientific evidence with links back to the original research so you can investigate for yourself which essential oils make the best insect repellants for soapmaking.

The factors affecting how effective an essential oil is as an insect repellant:

One of my favourite articles on this topic is a really detailed meta-analysis done by Maia and Moore in 2011, where they compared the results of a huge number of studies done on essential oils including citronella, neem, and the pine/cedar and mint families of essential oils. They found varying effectiveness. The main factor affecting how well an essential oil worked as an insect-repellant was the type of insect. Even different sub-species of the same insect could react differently to the same oil.

For example, two different types of mosquitoes are An. Arabiensis and An. gambiae. Studies have shown that citronella oil gives 90% protection from An. Arabiensis for 6 hours, and 100% protection from An. Gambiae for 6-7 hours.

Another example is thyme (variety: thymus vulgaris). This was found to offer 100% protection against An. albimanus for up to 105 minutes while it only offered 91% protection against C. Pipiens sallens for 65 minutes in a different study.

The concentration of the various natural compounds in an essential oil also makes a difference to the effectiveness. Using the above example again, thymus vulgaris offered 91% protection against C. pipiens sallens for 65 minutes when it was applied topically (directly on the skin) as linalool. When it was applied topically as thymol, it offered 91% protection for 70 minutes against the same insect. And when it was applied topically as carvacrol, it offered 95% protection for 80 minutes against the same insect.

This shows that different compounds in the essential oil can make it more or less effective. For best results, you need to ensure your essential oils are top quality and not diluted with any other compounds before you add them to your soap.

So if you’re looking to repel a specific type of insect, such as headlice, wasps or mosquitoes, it’s worth reading through this article to find out what will work best.

Which common essential oils work best as general insect repellants?

Citronella:

Citronella is widely known to be an excellent insect repellant. And now studies have been done to support this. The Israel Medical Journal published a double-blind study showing that, when citronella was used on school-age children, 12% got headlice, compared to 50% of the control group (who didn’t use citronella). That’s a reduction of 76%! Article here. It was also studied extensively in the article I discussed above, by Maia and Moore.

Neem:

Neem oil is well-known as an insect repellant. It has been shown to repel mosquitoes effectively by Sharma et al (1993) who found it provided 100% protection for 12 hours against mosquitoes. They mixed the neem oil with coconut oil then applied it directly to the skin. The results were published in the Journal of the American Mosquito Control Association. Article here.

In a second study, researchers looked at how effective neem oil was for repelling headlice. The study can be criticized as it had a complicated design measuring multiple factors at the same time (making it impossible to control variables), and a very small sample size (only 47 participants in total). The results showed combing with conditioner alone was 25% effective in removing lice while combing with conditioner and using neem oil was 35% effective in removing lice. The results were published in Advances in Pediatric Research. Article here.

Potentially confounding factors that made this research not very scientific include: The age of participants. Anyone from 6 months to elderly could participate. The participants were recruited from the local area and had to have at least “one headlice” to participate. Obviously, the treatment for someone with a mild headlice infestation or “one headlice” is going to be significantly easier than dealing with a severe infestation that has affected someone’s entire family for months. The home situation was not considered: It wasn’t considered whether pillows, bedding, towels etc were causing re-infestation before the person had been assessed as “cured”. In a home where multiple participants all have lice, the whole family should have been treated together and this was not done because they excluded anyone with specific hair treatments (e.g. coloured hair) and they didn’t control for cleanliness of the house, or sharing of hairbrushes, hats etc, all of which would cause re-infestation. So overall, I’m not happy with the lack of rigour of this study but it’s a great example of why “proven” results don’t always work the same way in real life.

In another multi-study review, Rossini et al (2008) found that neem oil had documented anti-lice activity. Link here. And in an analysis comparing evidence for neem oil and other natural oils for headlice, Heukelbach et al (2007) found that neem oil had an effectiveness of over 98%, repeated across two different studies. Unfortunately, the natural oils they looked at in this study were often mixed into other products so it’s not clear if it was the essential oils or other ingredients in those products that got results.

Tea Tree Oil

Tea tree oil is sold almost everywhere in the UK and Ireland and I think a lot of people use it to try and repel head lice. Di Campli et al (2012) found a 1% concentration of tea tree oil killed 100% of headlice within 30 minutes, and a 2% concentration also killed 50% of lice eggs (full article here).

In other parts of the world, it’s used against other insects. In a study in Indonesia, researchers showed tea tree oil repels and even kills T. castaneum (commonly known locally as the red flour beetle). Research results here (this will download a PDF file from the researchers, as the researchers haven’t put this on a web page for some reason).

Meanwhile Fonesca-Santos et al (2016) researched whether a commercial mosquito repellant could be made from tea tree oil and found it was very effective against the A. aegypti breed of mosquito. You can read about it here.

Great, but what about using essential oil to repel wasps?

Wasps are my main concern right now. We had two more in the house while I was researching and writing this article, today, and I’m so tired of ejecting them.

A study was done by Boevé et al (2014) to assess whether essential oils worked to repel wasps. They tested many different essential oils alongside conventional chemicals, and repeated their tests several times with different wasps, which makes the study more reliable. They found winterberry oil (galutheria procumbens), marjoram oil (o. marjorana), anything from the artemisia genus (over 400 species of plant, including tarragon and mugwort) and wild mint (m. arvensis) were all highly effective at repelling wasps (more effective than DEET, in fact). As far as chemical compounds go, they tested linalool (a natural chemical found in a lot of citrus plants, including citronella) with good results too. You can read about it here.

In another study by Zhang et al (2012), 21 different essential oils were tested to find out how effectively they repelled wasps (if at all). 17 of the essential oils were found to be highly effective, including clove, pennyroyal, lemongrass, ylang ylang, spearmint, wintergreen, sage, rosemary, lavender, geranium, patchouli, citronella, Roman chamomile, thyme, fennel seed, anise and peppermint. Read the full study here.

And finally…

As you can see, there is a huge amount of rigorous, repeatable, reputable scientific evidence proving that essential oils can make excellent insect repellants. For soapmaking, this gives you tons of options for making soaps that are insect repellent but which also smell nice. From my own experiments in this area, I recommend combining no more than three essential oils in one soap. Don’t try to make one soap that repels everything.

I suggest you make a test batch and try it on yourself in the shower before making a bigger batch to give to friends and family, as some of the strong insect repellant essential oils can also be irritants in soap or shampoo bars. For the same reason, you may want to reduce the amount of essential oil in your soaps to avoid ending up with itchy skin. Lastly, be extra-careful using any potent essential oil or other insecticide on children’s sensitive skin.


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So you’re probably looking for how to get your essential oils to be more intense in your soap. You might be making cold process soap or melt and pour soap. Maybe you’ve made some homemade soap with pure essential oils and it didn’t come out with a strong scent, or perhaps you’re planning your first homemade soap making project and are hoping to execute a perfect first-time soapmaking recipe…[read more]

How to safely use essential oils in home-made soap (infographic)

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Easy AHA exfoliating melt and pour soap recipe (variations for all skin types)!

This recipe is super-easy and so good for skin, especially in wintertime when dryness can be an issue. It seems like the combination of leggings, hot air indoors and going out on cold wintry days can cause skin to become flaky.

Add to that, on a cold day, no one wants to spend time moisturizing when they get out of the shower. I know at this time of year I’m so busy and cold, my skincare routine always goes right out of the window!

If you need to know how to get started with soapmaking, go here. Otherwise, read on and find out how to make an AHA exfoliating melt and pour soap. This recipe makes 1 bar of soap that should fit into a rectangular silicone soap mould, so scale it up to suit your needs.

Ingredients:

10 ml Cherry kernel oil

90g Melt and pour soap base

1 ml Cherry blossom fragrance

A pinch of sliced up loofah

Method (makes 1 soap weighing 100g):

  1. Cut about 90g (3 oz) of soap base from the block of melt and pour base. Chop the base finely and place into a glass jug.
  2. Heat the soap base in the microwave or place the jug in a pan of boiling water until all the base has melted.
  3. Add 10ml cherry kernel oil and about 0.5ml of fragrance.
  4. Mix in the sliced up loofah for extra exfoliating power. Once it’s all stirred up, pour into a soap mould and wait for it to harden.

How it works:

The cherry kernel oil is a natural AHA exfoliator, that helps get rid of dead skin cells on the surface of your face and body, increasing cell turnover and ditching dry skin.

Most AHA ingredients found in shop-bought products are chemically derived, whereas the cherry kernel oil retains its moisturizing properties, making it perfect for exfoliating dry winter skin!

The loofah helps speed up the exfoliating process by physically removing any dead skin (the stuff that can sometimes flake when you’re drying off after a shower).

An advantage of melt and pour soap is there’s no lye to handle, so this recipe is safe to make around pets or children. Having said that, be sure not to let them eat the finished product or any of the ingredients!

You can probably turn this into a cold process soap recipe, if you’re the sort of person who likes to customize every last ingredient in a soap recipe, but if, like me, you’re more excited about the finished product than the process taken to get there, melt and pour is a great choice!

Any melt and pour soap base will work fine with this recipe. I prefer the goat’s milk one but obviously, if you’re vegan, you would want to avoid that. The standard SLS/SLES free Stephenson’s melt and pour soap base is always a good choice, but there are so many choices for melt and pour soap bases, you’re bound to find one which becomes your favorite!

Variations:

Combination skin (oily and dry)? If you want this recipe to work better on oily skin, switch the fragrance oil for tea tree oil instead. The tea tree oil will help with hard-to-clean blocked pores and encourage spots to clear.

Super-dry, sensitive skin? Add 10ml avocado oil to this recipe, use no fragrance at all, halve the amount of loofah and be sure to use your usual cream(s) after the shower. Avocado oil is super-hydrating without being greasy or weighing your skin down (there’s nothing worse than feeling shiny after a shower, is there?) and many people with extremely dry skin find fragrance oils can dry them out even more, so making it unscented will help, too. By reducing the amount of loofah, you still get rid of dead skin cells but without causing irritation.

Oily skin? Add 1/4 tsp of French Red Clay (ultraventilated) and switch the fragrance oil for tea tree oil. The French red clay will help control oil production from your pores, and draw impurities out of them, while the tea tree oil will help with problem spot areas.

Did you try this recipe? Let me know in the comments!

Easy breastmilk soap recipe

Do you have excess breastmilk or oversupply of breastmilk? Perhaps you are looking for a way to preserve your breastmilk or turn it into a beautiful gift? If you’re anything like me, after six months or a year of breastfeeding, you have a freezer full of breastmilk and you want to do something with that liquid gold!

A breastmilk pendant is a beautiful idea but let’s be fair, it doesn’t use much of that milk. You’ll still have boatloads of the stuff left!

In New York beauty salons, breastmilk is seen as the “miracle ingredient” that can work wonders for your skin. People pay hundreds of dollars for breastmilk facials. Midwives often tell new mothers to put breastmilk on their sore nipples in the early days because of its amazing moisturising properties.

I have so much milk sitting around. I tried giving it away to hungry babies three months ago, and I didn’t get any takers in my small country. Instead, I decided to try turning it into various beauty products. Some came out better than others. Don’t make the mistakes I did. If you’re looking for a really quick and easy thing to do with your leftover breastmilk, here’s a fabulous simple melt and pour breastmilk soap recipe.

It uses something called melt and pour soap base, which is ready made for you to turn into soap. All you have to do is follow this easy breastmilk recipe to get the most creamy and cleansing bars of soap you ever tried! It’s also sulphate free and paraben free!

You will need:

A silicone soap mould I have these ones but you can get identical ones in the US here.

Stephenson’s melt and pour SLS free soap base available in the US here or here in the UK.

A microwaveable or heat proof glass jug (you need at least 500ml/1 pint, available here in the US and here in UK but they’re cheaper in Tesco if you’re near one).

A spatula for mixing (any non-metal spatula or wooden spoon will work).

A sharp knife to cut the soap base (any kitchen knife will be fine as long as it hasn’t blunted and the handle is safely attached to the blade).

Breastmilk.

The soap base is sold in boxes of 1kg and if you wanted to turn all of it into breastmilk soap you would need 500ml of breastmilk, but do not worry if you have less breastmilk. To make it as easy as possible, I’ve done this in 250g blocks of melt and pour soap base, which is a quarter of a tub and will fill your soap mould.

Method:

  1. Cut the 1kg block of Stephenson’s melt and pour SLS free organic soap base into quarters with a knife
  2. Taking one quarter of the soap base (roughly 250 grams), chop it into small squares and melt it in a glass jug in the microwave or put the glass jug into a pan of hot water just like you would if you were melting chocolate to make chocolate krispy cakes. Microwave on a low heat (I go for the lowest setting) for about 2 mins, check, then put it back in, checking every 30 seconds to 1 minute until it’s melted.
  3. Once the soap base is melted, add 125ml of cold (but not frozen) breastmilk and stir it well to get it all to mix.
  4. Pour your mixture into your soap mould. You can put it into the fridge to solidify faster, but don’t leave it more than an hour as melt and pour soap base contains glycerin which will start to draw moisture out of your fridge and make the soaps less solid!
  5. Once your soaps have solidified, turn them out and wrap them. Most people advocate putting them in plastic wrap such as saran wrap, but I prefer beeswax paper or baking paper as these are better for the environment.
  6. Use your soap! I found this to be super-moisturizing compared to store-bought soaps.

I love this straightforward and easy breastmilk soap recipe but I have made a few others, too, which I will post in the future.

breastmilk soap1