Ok I am really trying to figure this one out. Half the stuff on the list has no properties or variables which in any means would provide a repellent
Sundrop,
The majority of the mix is called the "carrier". The Witch Hazel and the oils are meant to dilute the "essential oils" down to an appropriate level so they won't irritate the skin. You don't want to apply the essential oils or extracts directly to the skin since they are so strongly concentrated. Trust me, the bugs get the idea with just a little taste of these essential oils. You won't be "bugged" if you use this recipe, the bugs won't even come near you! I gaurantee it!
Using alcohols or oils to carry the essential oils can be benficial in several regards, aside from diluting the main ingredients that repel the insects. The oilier the carrier is, the less the mixture's tendancy to evaporate and thus it remains on the skin longer and provides longer coverage. The more alcohol used, the better suited the mix is for spray applications (a mist spritzer like you would use for your house plants).
Witch Hazel is an excellent carrier agent because it is so inexpensive and well regarded as a skin conditioner or astringent. Skin So Soft is meant to be used as a skin conditioner, too. But, it has insect repelling properties all on its own.
The Jojoba oil, the Ivy Block lotion and the zinc acetate (Wal-dryl) ingredients are just items that I added to help dilute the mix and provide some further benefit.
If a person wished to reduce the recipe to key components alone:
20 oz Witch Hazel
2 oz Avon Skin So Soft
152 drops Lemongrass Oil
76 drops Geranium Oil
76 drops Vanilla extract (pure)
76 drops Eucalyptus Oil
76 drops Peppermint Oil
76 drops Tea Tree Oil
Finding the proper balance between oils and alcohols is key to making this repellent more convenient for use. It is recommended that you keep the percentage of the total essential oils below 10% to avoid skin irritations.
The Lemongrass, Rose Geranium (that is actually citronella), vanilla and peppermint are the tops for insect repulsion. The other oils are also very good, but these are key. If you want to reduce the cost of the mix, don't skimp on these ingredients. It is really amazing how well this stuff works. 100% DEET doesn't even come close and most people don't like to use chemicals like DEET, especially on children or pets.
RADAR