Essential Oils are incredibly safe, but it is important to learn how to use them.  There is great information below, as well as at this link: https://www.youngliving.com/discover/essential-oil-safety

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A "carrier oil" is a fatty vegetable oil that is used to dilute essential oils.  Some favorites to use are Coconut Oil, Fractionated Coconut Oil (liquid), Jojoba, and Young Living's V6 Vegetable Oil Complex. 

Carrier oils ensure that essential oils applied topically are comfortable to the skin. Dilution with a carrier oil does not dilute the effect of the essential oil. In fact, it prevents waste due to excessive application. Look for dilution ratios on Young Living essential oil bottles.

Vegetable shortening, butter, margarine, or petroleum derivatives (such as mineral oil, baby oil, and petroleum jelly) should never be used as carrier oils.

Image copyright Young Living Essential Oils