With so many mosquito-ridden countries coming up on our itinerary (Thailand, Vietnam and Cambodia have already been booked and more to come), our thoughts have naturally come finding the best insect repellent on the market.
In my naivety, I was under the erroneous impression that all mosquito repellents were created equal and only the branding was different, similar to Nurofen and the multitude of generic ibuprofen brands. This, I have learned, was false and I am dumb for thinking any different.
Not only do they come in a multitude of brands, they all seem to have different active ingredients with wildly conflicting opinions online of their efficacy and safety. Should we be using Picaridin or IR3535? How much DEET is too much DEET? Come with me on a journey to find the best insect repellent on the market (according to science).
How I went about choosing the best repellent for us
I started my research with this comprehensive testing performed by Consumer Reports. What makes the results of their testing so interesting is that they’re an objective, non-profit entity (similar to Which in the UK), so their opinions should be unbiased.
In their quest to find the best insect repellent, they tested dozens of products by applying them liberally to the arms of hapless volunteers and sticking their exposed arms into boxes full of hungry mosquitoes.
What were the Consumer Reports mosquito repellent test results?
Firstly, they found that a lot of the products on the market were either completely useless or stopped providing any protection after less than two hours, which scientists agree is “too damn short”.
With the exception of lemon eucalyptus, the natural options were all rubbish. Cedar, citronella, lemongrass, and rosemary all provided little to no protection.
The found that the best insect repellents were those that contains DEET, Picaridin or oil of lemon eucalyptus. They also claimed that DEET was safe for everyone (including children) and that the most effective concentration was 15-30% of DEET (any higher than that would be higher risk).
They recommended against the combined repellent and sunscreen, reasoning that sunscreen should be applied every couple of hours, whereas even the best insect repellent should be applied at longer intervals.
Which mosquito repellent we chose
After that decent into mosquito repellent madness, you’re probably wondering which option I went for in the end.
I opted for the Jungle Formula (Medium), which has 20% DEET. The other option was the Jungle Formula (Maximum), which has 50% DEET but, based on the Consumer Report findings (and the concerns over safety detailed below), I felt that was a bit too strong for us.
For the best insect repellent for the kids, I’m still doing some more research. The 4-year old can use the Jungle Formula (it says safe from 3 years) but the 2 year old will need another product. Jungle Formula do actually have a kids mosquito repellent, but the product information says “for use in countries with no known risk of malaria or other insect transmitted diseases”, so I’ll need to do some more research.
More information on mosquito repellent
During this hours-long dive into the recesses of the internet, I’ve come across several other interesting resources about mosquito repellent which might help you when choosing yours.
Is Deet safe?
In 2009, some of the British press (including the less-than-trustworthy Daily Mail Online), claimed that a scientific study had found potential health risks associated with the use of DEET.
The NHS has a very helpful and very detailed explanation of what the study actually found and how it should be interpreted.
In short, they agreed that the study had found that DEET “does not simply modify the behaviour of insects, but also directly inhibits enzyme activity, both in insect and mammal nerves”.
Based on that finding, their recommendation was rather measured.
This laboratory study has raised important questions regarding the mechanisms behind the action of DEET, a common ingredient of many insect repellent products. Further research is required to answer these questions effectively.
Although it is not surprising that an insect repellent is toxic to insects, the newly discovered mechanism of the repellent is something that will need evaluation. Particularly important will be studies that investigate the ideal dose that can repel insects without running the risk of serious toxic effects in humans. These results must also be weighed up in relation to the risk of diseases carried by mosquitoes in tropical countries, particularly malaria. The potential harms of restricting DEET use must be considered in order to reach a balanced view on this issue.
What are the active ingredients of mosquito repellent
- DEET
- Picaridin
- Oil of Lemon Eucalyptus
- IR3535 and 2-Undecanone
DEET
DEET is the most common active ingredient in mosquito repellent. It was developed in the mid 20th century by the US military after their soldiers were bitten to shreds during World War 2 and was used in South East Asia during the Vietnam war. It’s very effective but there are a number of potential side effects.
Picaridin
Considered as effective as DEET but without the side effects. It “demonstrates excellent repellent properties comparable to, and often superior to, those of the standard DEET” according to the World Health Organisation and is recommended (alongside Deet and Lemon Eucalyptus) but the US Centers for Disease Control & Prevention.
Oil of Lemon Eucalyptus
This was the only natural product that the Consumer Report testing found effective. It’s a refined version of the essential oil derived from the lemon-scented gum of the Lemon Eucalyptus tree.
