I take my daughter to a woodland playgroup almost every Thursday morning. In the summer, the woods are swarming with midges. Being quite intelligent little beasties, these midges look for shelter underneath trees and the undergrowth. It is even worse when it rains and that, unsurprisingly, happens a lot in Scotland.
I found myself between a rock and a hard place:
- I did not want to spray a strong insect repellent on her delicate skin (or my own) feeling unsure of its potential toxicity.
- I did not want to come home with her face (or mine) red and swollen from midgey bites.
So I needed to find out:
- How toxic are the conventionally sold insect repellents and how harmful are they to our health and the environment?
- What alternatives do I have?
Conventional DEET-Based repellents – How toxic are they?
Most of the strong and most effective insect repellents on the market contain a chemical called DEET. Diethyl-m-toluamide or Diethyl-3-methylbenzamide (DEET for short) is a pale yellow, slightly oily liquid. It was created in 1946 for the US army to protect them on operations in tropical environments following their experience of jungle warfare during the Second World War. It became available for the civilian market in 1957.
The downside to using DEET is that about half of it is absorbed through our pores and some of it will enter the bloodstream.
The good news: Serious effects on our nervous system are unlikely to occur from light use. The main possible side-effects are skin and eye irritation. If you adhere to the manufacturer’s instructions, these products should generally be safe to use. The recommendations are usually: don’t use it on broken skin and wash it off when you no longer need it. It is thought to be safe enough for use by anyone over the age of 2, although pregnant mothers and children should use a concentration no higher than 30%. The Environmental Protection Agency has classified it as ‘slightly toxic and slightly irritating’ if it enters your body through skin, eyes or mouth. Its toxicity grade is 3, the second lowest of 4.
It does, of course, also pose environmental hazards. It remains in soils, where it is broken down by bacteria and fungi. This process reduces its toxicity. Because of its ubiquitous use by humans, however, traces have been detected in wastewater. The biggest problem is its high toxicity in regard to fish and other aquatic life. If you use it as a spray, the vapour will break down in the atmosphere relatively quickly, depending on conditions like temperature, humidity and wind.
Are there any alternatives to chemical insect repellents? And how well do they work?
Here are some commonly used alternatives suitable for the European and North American environment. There are also some commercial ones which are a lot milder than DEET-based ones. In general, when outdoors it is always wise not to rely on a single insect repellent to do the trick. Protect yourself with more than just the spray depending on the type of activity and the length of time you are planning to spend outdoors.
The Environmental Working Group (EWG) analysed several repellents.
⇒ Citriodiol and Citrepel, Pyrethrin and Citronella
- Citriodiol and Citrepel are also known as Oil of Lemon Eucalyptus – the essential oil that is obtained from the leaves of the Eucalyptus Citriodora tree (p-Menthane-3,8-diol – or PMD for short). It is not the same as Citronella. Citriodiol is of extremely low-risk toxicity when used on your skin or accidentally ingested but it can cause severe eye irritation. Other active ingredients are Icaridin and Saltidin.
- Pyrethrin is an extract of the Pyrethrum plant, commonly known as Chrysanthemum. Pyrethrin is highly effective as an insect repellent but is practically non-toxic as far as mammals and birds are concerned. There is one interesting exception: cats react to it and should not be used in close proximity to them as they are very sensitive to it. It is also harmful to fish and other aquatic organisms.
- Citronella is derived from the leaves and stems of Cymbopogon – a tropical grass from Sri Lanka or Java. It is non-toxic but can act as a skin irritant which makes it unsuitable for very young children.
I tested these and found they worked quite well:
A. The simplest one is a lavender oil roll on. It helps but is often not quite enough to fend them all off. It works well in conjunction with netting and other repellents such as citronella candles or coils.
B. Another possibility is an alcohol-based recipe. It is safe enough for adults, but I’d rather avoid it with kids’ delicate skins.
- 60 ml of alcohol (min. 40 per cent Vol.)
- 40 ml Water (distilled or purified)
- Add 10 drops of essential oil such as citronella, eucalyptus or lavender
C. A softer alternative is a recipe based on witch hazel which you can order here.
- Mix cooled boiled water and witch hazel at equal quantities, say 50/50 for 100ml
- Add 20 drops of essential oils for every 100 ml of liquid
Use essential oils such as citronella, tea tree, eucalyptus or lavender
D. And this is a bit oily but really keeps them off your skin
- Mix 30 drops of tea tree oil and 10 drops of geranium oil in a little bit of carrier oil such as Almond, Neem or Vitamin E
- Add 1 Tbsp of Vegetable Glycerin
According to Pronounce Skin Care, a bit of Vanilla Extract added to the mix makes all the difference.
If you want to go completely spray-free, you may want to try wrist bands. Wrist bands still contain DEET and need to be disposed of once they have ended their life cycle. Look here for a comparison of different brands.
We need to balance up potential risks of insect-borne diseases against the health and environmental hazards of the chemical ingredients. I found the above alternatives very effective, although I would only use them in an environment I consider safe enough. They are certainly suitable for a day out in the woods in Scotland or elsewhere in Europe and North America. When travelling to a high-risk area, I would consider other alternatives.
Stay safe and healthy!