It’s that time of night when sitting on the balcony becomes a feat of endurance rather than a pleasure and it’s down to those vile biting mosquitos. Time to take action… but what kind. I could of course slather myself in DEET…

DEET Was developed by the American Army and remains the most effective form of bug repellent known to man. It is a great weapon in the fight against malaria. But it can irritate my skin and has had other negative press. Plus it comes in plastic.

So what of the alternativee? Needless to say the internet offer everything from wristbands to essential oils. Lots of testing has been done which conclude that these range from considerably less effective to completely useless. “Two devices in particular came under harsh criticism from the scientists: bracelets containing herbal extracts and sonic mosquito repellers, which claim to use high-frequency sound to drive away mosquitoes.” And dont bother with citronella candles. You can read the rest here.
That said there is some evidence that certain essential oils (including citronella) might  work.SO let’s discuss the options.

Why DEET
Just to reiterate N-diethyl-3-methylbenzamide (deet) DEET is the most effective insect repellent ever.
Then (2-(2-hydroxyethyl)-piperidinecarboxylic acid 1-methyl ester (icaridin), p-methane 3, 8-diol (PMD), and ethyl butylacetylaminopropionate (IR3535)-based repellents also provide protection against biting arthropods,
Malaria & Other Nasty Deseases
Malaria is extremely dangerous and kills masses of people each year. DEET Will protect you from mosquitoes and many other disease bearing blood suckers. If you are in a malarial prone area then it is an essential means of protection and I advise you consider it. Medical plastic is exempt from the boycott. To quote DEET must be the “first choice for those visiting areas where malaria or other arthropod-borne diseases are endemic remains formulations with higher concentrations (20–50%) of deet.
Higher concentration icaridin and PMD preparations are the most useful alternatives to deet where they are available”
Read more here

How Strong?
What do these concentrations mean? A higher concentration of DEET means it will last longer. 20% DEET offers up to 6 hours of protection. 50% DEET which offers 12 hours of protection. If you sweat heavily you’ll need to re-apply it more often, obvs.
According to the British Medical Journal anything with over a concentration of 50% DEET will not be any more effective. Read this very good write up that discusses all the issues and gives clear advice on how DEET should be used. Access it here.

Bad DEET
But if you are not at risk from malaria you might want to limit your exposure to DEET. While DEET is generally thought to be safe there are reports of possible reactions. On a personal level I find it irritates my skin but then again so do most perfumes and some soaps. However it is not just me. Reactions to DEET have been documented. And they can include Hives or mild skin redness and irritation. The more you use the worse it gets. People using products containing a large amount of DEET over a long period of time may have more severe skin reactions that include blistering, burning, and permanent scars of the skin.
Wikipedia are even more worrying and report that
In the DEET Reregistration Eligibility Decision (RED) in 1998, the United States Environmental Protection Agency (EPA) reported 14 to 46 cases of potential DEET-associated seizures, including 4 deaths. The EPA states: “… it does appear that some cases are likely related to DEET toxicity,” which may underreport the risk as physicians may fail to check for history of DEET use or fail to report cases of seizure subsequent to DEET use.[21]
The Pesticide Information Project of Cooperative Extension Offices of Cornell University states that “Everglades National Park employees having extensive DEET exposure were more likely to have insomnia, mood disturbances and impaired cognitive function than were lesser exposed co-workers”.[22].
Read it here

Which Alternatives Work
So for those munchy twilight hours when the biting, but non-malarial carrying beasts are out DEET seems rather a chemical sledge hammer. In these cases I have been using Cintronella essential oil mixed with Rice Bran oil as a mosquito repellent. Based on nothing more than a quick skim of alternative bug sprays on the internet and the fact I have some Citronella oil. The internets claims all kinds of wonderful qualities for Citronella but I tend not to believe them. So consequently I didnt know if my homemade repellent really worked i.e.if it actually repels Mosquitos. But I felt it did and it certainly seems to soothe bites and reduce irritation. So I decided it was time to do some research.

Citronella
Citronella is  obtained from the leaves and stems of different species of Cymbopogon grasses. And it might just work. This is a quote from some research that seems reputable.  “From the available literature and information, we can conclude that the complete protection time for citronella-based repellents is less than 2 hours”
Read more here

But 2 hours is all I need. I can live with the occasional bite at other times it’s the twilight feeding frenzy I object to.

Using Essential OIls
Essential oils are concentrated and so should be used with some care.
Do not apply neat to the skin.
It is good practice to do an allergy test
Do some further research into the oil you plan to use

Disclaimer
Be aware of the risks of listening to someone who
a) doesn’t have any training in this field,
b) most of what they know comes from Google,
That’s me I mean.

Making Mosquito Repellent
You should never use essential oils neat so the Citronella has to be blended with a base oil. And there is very little data avaialable on what kind of percentages to use for the oil to be effective against biting beasts.

Generally Most essential oil/ aromatherapy sites say that mixes of essential oil to base oil should not exceed 5%.
A good rule of thumb when seeking to make a 2% dilution is to add 12 drops of essential oil to each fl. ounce (30 ml) of cold pressed carrier oil, lotion, vegetable butter or other natural lipid/moisturizer.
There is a useful dilutions chart here

And then there is this:
For adults:
Sensitive skin: .5 to 1 percent dilution = 3 to 6 drops per ounce
Normal, healthy skin: 1 to 2.5 percent dilution = 6 to 15 drops per ounce
There is lots of useful information here

My Mosquito Oil
So I added Citronella to a base oil at a 5% ration. I have used coconut oil, rice bran oil and rapeseed oil as bases. All work well.
I spread this on all exposed flesh when the sun begins to set. I only apply it once.

Obviously we are not talking about huge percentage of active ingredient here. Certainly not the 30% of DEET creams. How effective this oil is I have no way of knowing. I can only say it seems to work for a limited period of time.
AND PLEASE NOTE
These blends have not been tested for skin reactions or allergies. It is worth remembering that DEET lotions have been used for years and have been well tested.
I am telling you of my own experiences for your information only. You should do a lot more research before proceeding. And proceed with caution.
None of the above have been tested on anyone other than me. All I can say Is that I have used essential oils for a long time with no ill effects…..
Also
Essential oils are resource hungry, have a large environmental footprint and should only be used on special occasions. You can read more about essentials oils, what they are and how they are obtained here.

Buy

Plastic Alert
Vegetatable oil will nearly always have a plastic element unless you are lucky enough to find a refill service. Even if you buy in glass the lid will be plastic lined. But even so this represents a huge reduction in you plastic consumption. Read more and links on where to buy, here.

Same goes for essential oils.

More

There is an interesting breakdown of mosquito myths here. Plus some useful advice on how to avoid them.
And this is an interesting article on using plants to deter insects
And I am looking into this.
“PMD: Lemon Eucalyptus (Corymbia citriodora) Extract
The principal repellent component of lemon eucalyptus extract is PMD, which is the main by-product of lemon eucalyptus hydrodistillation.
The active component is prepared through acid modified extraction of leaves or a synthetic version of PMD is used in the majority of commercially available preparations.”
Read about it here.