English lavender oil is obtained through distilling the flowering tops of Lavdanula angustifolia, a small shrub in the mint family native to the Mediterranean area that produces purple-blue flowers. The oil is widely used to help with anxiousness and to promote restful sleep, and its safety and efficacy has been evaluated in published clinical trails. Lavender oil is also a popular ingredient in personal care, home care, and cosmetic products.
Substitution with other less expensive species of Lavandula have been reported, apparently due to the relatively high cost of English lavender essential oil. Lavandin is one of the most frequently mentioned adulterants, the BAPP reports, though it is considered an acceptable substitute by some international authorities. Other common cases of adulteration include the undeclared addition of other essential oils, or oil fractions rich in the natural chemical compound linalool, such as rectified or acetylated ho wood oil (obtained from a linalool-rich chemotype of camphor, Cinnamomum camphora), eucalyptus, and white camphor oil fractions.
Essential oil fractions are parts of the oil that can be separated from the rest by various processing steps, such as fractional distillation. Admixture of undisclosed purified or synthetic components, such as linalool and linalyl acetate, or non-volatile diluents, appear to be quite common as well, BAPP said.
“Over the course of my tenure at ABC, several lavender gorwers and lavender oil manufacturers have raised concerns about the presence of relatively low-cost, adulterated materials in the marketplace,” Stefan Gafner, PhD, chief science officer of the American Botanical Council and BAPP technical director, said. “We hope that this new bulletin will be a useful educational resource for everyone with interest in the quality of lavender oil.”
The bulletin was authored by Ezra Bejar, PhD, whose area of expertise lies in medicinal plant research. It was also peer-reviewed by 25 experts specializing in lavender oil from academia, contract analytical laboratories, consulting services, trade organizations, and the industries of botanicals and essential oils. The bulletin provides additional information on the production and market importance of English lavender oil, a review of the available literature on adulteration, data on adulteration frequency, and analytical approaches to detect adulterants.
Mark Blumenthal, the founder and executive director of ABC and the director of BAPP, said that the issue of adulteration is becoming increasingly prevalent with the growing popularity of this ingredient.
“There has been a surge of interest in the United States and wordwide in the personal and household uses of essential oils, with lavender being one of the most popular,” Blumenthal said. “The existing scientific literature and BAPP’s new research indicate that a significant amount of of what is sold as ‘lavender oil’ in the marketplace is adulterated with undisclosed, lower-cost ingredients. As in all cases of botanical ingredient adulteration, industrial buyers are urged to employ significant caution and robust analytical methods to determine the proper identity and authenticity of material being considered for purchase for use in finished products.”
On the other hand, Blumenthal noted that there are numerous companies selling lavender oils which meet various internationally-recognized standards for identity and purity.
“As in most cases of adulteration of botanical ingredients and essential oils, ethical and responsible sellers of authentic material find it challenging to compete in the marketplace with sellers of low-cost products containing undisclosed levels of diluted, adulterated, and/or otherwise fraudulent oil.”
The English lavender oil bulletin is the 21st bulletin of this kind published by BAPP, and represents the 59th peer-reviewed publication by the program. Like all other BAPP publications, the bulletin is freely accessible to all members of the public on BAPP’s website.