DEET Condemmed, While Essential Oils Are Shown Effective as Insect Repellents
Recent news has confirmed suspicions regarding the health effects of DEET, the world's most commonly used insect repellent. DEET, which is the acronim for the chemical N,N-Diethyl-3-methylbenzamide. The chemical has now been implicated in potentially causing damage to the nervous system, and may be particularly harmful to children -- who's developing physiology is more sensitive to chemical toxins.
Essential oils such as Citronella have long been successfully used as insect repellents. Some have been shown significantly more effective than DEET at repelling mosquitos: Catnip essential oil has been noted to be up to 20 times more potent than DEET. Many natural insect repellents employ a blend of essential oils such as Geranium, Cedarwood, Lemon Tea Tree and others. Here are a few studies published by the scientific community confirming the effects of essential oils as mosquito repellents -- your own formulation is particularly easy to make, too. You can simply select the essential oils of your liking, and add them at a fairly strong concentration (7% to 15% total essential oils) to an unscented lotion such as our Jojoba/Coconut cream base.
Study: Repellency effect of forty-one essential oils against Aedes, Anopheles, and Culex mosquitoes.
Amer A, Mehlhorn H. Omar Almukhtar University, P.O. Box 919, Elbieda, Libya.
Since ancient times, plant products were used in various aspects. However, their use against pests decreased when chemical products became developed. Recently, concerns increased with respect to public health and environmental security requiring detection of natural products that may be used against insect pests. In this study, 41 plant extracts and 11 oil mixtures were evaluated against the yellow fever mosquito, Aedes aegypti (Linnaeus), the malaria vector, Anopheles stephensi (Liston), and the filariasis and encephalitis vector, Culex quinquefasciatus (Say) (Diptera: Culicidae) using the skin of human volunteers to find out the protection time and repellency.
The five most effective oils were those of Litsea (Litsea cubeba), Cajeput (Melaleuca leucadendron), Niaouli (Melaleuca quinquenervia), Violet (Viola odorata), and Catnip (Nepeta cataria), which induced a protection time of 8 h at the maximum and a 100% repellency against all three species. This effect needs, however, a peculiar formulation to fix them on the human skin. (Ed. note: this simply means diluting them in a carrier or unscented lotion).
Study: Repellent activity of essential oils: A review.
Nerio LS, Olivero-Verbel J, Stashenko E.Environmental and Computational Chemistry Group, Campus of Zaragocilla, Faculty of Pharmaceutical Sciences, University of Cartagena, Cartagena, Colombia; Chromatography Laboratory, Research Center of Excellence, CENIVAM, Industrial University of Santander Carrera 27, Calle 9, Bucaramanga, Colombia.
Currently, the use of synthetic chemicals to control insects and arthropods raises several concerns related to environment and human health. An alternative is to use natural products that possess good efficacy and are environmentally friendly. Among those chemicals, essential oils from plants belonging to several species have been extensively tested to assess their repellent properties as a valuable natural resource. The essential oils whose repellent activities have been demonstrated, as well as the importance of the synergistic effects among their components are the main focus of this review.
Essential oils are volatile mixtures of hydrocarbons with a diversity of functional groups, and their repellent activity has been linked to the presence of monoterpenes and sesquiterpenes. However, in some cases, these chemicals can work synergistically, improving their effectiveness. In addition, the use of other natural products in the mixture, such as vanillin, could increase the protection time, potentiating the repellent effect of some essential oils. Among the plant families with promising essential oils used as repellents, Cymbopogon spp., Ocimum spp. and Eucalyptus spp. are the most cited. Individual compounds present in these mixtures with high repellent activity include alpha-pinene, limonene, citronellol, citronellal, camphor and thymol. Finally, although from an economical point of view synthetic chemicals are still more frequently used as repellents than essential oils, these natural products have the potential to provide efficient, and safer repellents for humans and the environment.