An essence oil is not the same thing as a steam distilled oil, and this is the clearest illustration of the difference. It is recovered from the oil phase of expressed citrus juice, which is why it smells the way a lemon actually tastes: bright, zesty, and carrying an estery fruitiness that steam distilled lemon simply does not have.

Plant Therapy sources the fruit from Argentina, Italy and the United States. Diffuse five to six drops per 100 mL of water. The label notes that it can cause photosensitivity and caps topical use at 2 percent in a carrier. It carries the maker's KidSafe, Nursing Safe, Pregnancy Safe and Pup and Pony Safe designations.