HOW TO FORMULATE INSECT REPELLENT

An insect repellent is usually a liquid that is used on the skin or clothes to discourage the climbing or landing of insects like fleas, flies, mosquitoes and ticks on the surface.
Normally repellents work by masking carbon dioxide, lactic acid and sweat odors that are emitted by the human body and by having a specific scent that insects avoid.
The best proven chemical repellent is DEET ( N,N-Diethyl-m-toluamide; C12H17NO).
A concentration of 0.1 grams is enough to act on a 72 square inch area of skin.
Formulations are basically based on a 5 to 25 % concentration.
A typical formula contains: 10 % DEET, 40 % Alcohol, 0.5 % Carbomer, 48.5 % Water and 1 % of a 50% solution of TEA. Simply add the carbomer to the Alcohol and DEET and then add slowly the water and finally the TEA.
A natural repellent can be made by using Geranium oil, Citronella oil, Lemon Eucalyptus oil and also Vitamin E has proven to be effective in an oil suspension.