Insect repellents Types of insect repellents
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This article, Insect repellents, was last updated on 07 May 2009 and is now out of date and held in our online archive for reference. Explore our latest Home & garden articles.
These sunglasses were sprayed with 100% DEET
DEET
Diethyl toluamide, or DEET, was developed by the US Army in the late 1940s, and was made available to the public in the 1950s.
It is the most commonly found insect repellent, and has been shown to be effective over its 65 year life.
DEET can be purchased at various concentrations, but for most holiday destinations a concentration of 30% is sufficient.
Insect repellents with a DEET concentration of 50% to 100% are for use in exceptionally high-risk environments, where there are high numbers of malaria-carrying mosquitoes, or where you are subjected to continued exposure.
The following is a rough guide:
- Insect repellents with DEET concentrations of up to 30% Should be adequate for most holiday destinations
- 50% DEET insect repellents Can be used by children and adults and are recommended by the HPA
- 100% DEET insect repellents Should be used on clothing only
Can DEET damage clothing and other materials?
DEET is known to melt some hard plastics. You should be careful to ensure plastics, such as rucksack clips or sunglasses, do not come into contact with DEET, as it may damage them.
We sprayed some 100% DEET on some sunglasses, and it totally destroyed them.
Clothing should, in general, be OK when sprayed with DEET, unless it has any plastic accessories.
Use of DEET during pregnancy, while breast-feeding and on children
If you are pregnant, the general advice is to avoid malarial areas, as the risk of infection is greater because your immune system will be weaker.
If you must travel, the Health Protection Agency recommends using insect repellents containing 50% DEET. Similarly, the HPA says 50% DEET products are safe to use while breastfeeding, and on infants over two months old.
Other chemical-based products
There are several chemical insect repellent alternatives to DEET such as Lcaridin (also known as Bayrepel).
While they may have excellent insect repelling properties, none have been proven to be as effective at repelling insects as DEET is.
Some of these insect repellents will offer adequate protection in lower-risk areas, but regular reapplication may be required.
See our full list of results for details of all products that do not contain DEET, but still offer excellent insect repelling properties.
However, if you are going to a high risk malarial area then the advice is to use a DEET based product.
Natural products
There are many natural insect repellents, with an increasing range becoming available as people try and find natural alternatives to DEET and other chemicals which can have a less than pleasant aroma.
Some people also claim that DEET is toxic, but there has been little evidence in its 60 year lifetime to back this claim up.
Claimed active ingredients of natural repellents are wide ranging and include garlic, citronella and eucalyptus. Some of these products will offer good protection from biting insects, but others less so.
It should be remembered that regular reapplication will be required to ensure that your level of protection remains as high as possible.
Reapplication rates will vary depending on your activity – if you are cycling and sweating lots, you will need to reapply more regularly than you would if you are sitting around reading a book.
Avon Skin So Soft
There is much internet chat, and even a rumour that it is used by many soliders, suggesting that Avon’s Skin So Soft is an effective insect repellent, though Avon makes no such claims.
There is even a website – which isn’t connected with Avon at all – that sells it as an insect repellent.
We thought we’d see if the rumours were true – sadly they are not. It may keep your skin super soft, but did not do much to deter the mozzies.
Buzzer repellents
It may be tempting to try an electronic buzzer that’s claimed to scare away mosquitoes, but our previous tests in 2005 showed these to be ineffective.
To check again, we tested a buzzer that had just been released, but it failed to scare away any mosquitoes.
The test results confirm our view that these insect repellent devices offer nothing apart from a false sense of security – a view backed by the HPA.
