00:15 --> 00:34
Speaker 1
Hello everyone! Welcome to the Assurance in Action podcast. Today’s podcast is dedicated to cosmetic industry and will focus on the safety assessment of essential oils. My name is Héloïse Piketty, pharmacist and toxicologist with Intertek Assuris, and today I am with Marine Soler, also toxicologist within the team.
00:35 --> 01:15
Speaker 2
Thank you, Héloïse. Hello, everyone ! Because of the complexity of this subject, we will discuss it over 2 podcast episodes. In this first episode, we will discuss what an essential oil is and why safety assessments of essential oils are so complex. In recent years there has been great interest in essential oils, with consumers wanting to turn to more natural products. However, just because essential oils are natural substances derived from plants known for thousands of years doesn’t mean they should automatically be considered safe for consumers!
01:16 --> 02:01
Speaker 1
Exactly, and to understand this, we need to start by defining what an essential oil is. An essential oil is an odorous product, generally of complex composition, obtained from a vegetable raw material. Three extraction processes can be used to obtain an essential oil from aromatic plants: mechanical expression of the peels of citrus fruits, steam distillation, and, for certain plants, dry distillation. These processes allow us to extract the essence of the plant and concentrate its compounds. The extraction yields are quite low—to produce 1 kg of essential oil, between 10 and 20,000 kg of plants are needed, depending on the plant.
02:02 --> 02:06
Speaker 2
What does this mean from an analytical point of view?
02:07 --> 02:33
Speaker 1
Well, an essential oil contains hundreds of components with related or distinct chemical structures. Each component has different properties and toxicities and even components present in very small quantities can have marked actions on the human body. For example, bergapten, one of the compounds responsible for phototoxicity, is found in bergamot oil at concentrations of about 0.3%.
02:35 --> 02:51
Speaker 2
Indeed, you're right. The rich composition also explains why they have many properties: relaxing antiviral, antibacterial, antiparasitic, etcetera. But these effects are accompanied by toxicity, which must be evaluated.
02:52 --> 03:16
Speaker 1
Yes, and assessing the safety of an essential oil is complex for several reasons. Not only is a composition of an essential oil complicated, but the geographical origin of the oil can impact its safety profile. Let's take an example. If we consider the essential oil of thyme, and one of the most common species, Thymus vulgaris, we can identify about 10 chemotypes!
03:17 --> 03:40
Speaker 2
Correct and chemotypes are very important when we talk about essential oils. A chemotype is a kind of the identity card of the essential oil and some of these identities dominate in the global composition. For Thymus vulgaris, we often see the linalool chemotype, geraniol chemotype, thymol chemotype, or thujanol chemotype, just to name a few.
03:41 --> 04:09
Speaker 1
Thanks for the clarification. As mentioned, Tthe chemotype of the essential oil is dependent on the geography of the crop. Sun exposure, the composition of the soil, the physico-chemical properties of the soil, rain conditions, and altitude are several factors that influence the composition of the essential oil. Even an essential oil which is extracted from the same crop has a different composition each year!
04:10 --> 04:22
Speaker 2
And not only that, within the same chemotype, the composition of the essential oil is not identical. As part of a safety assessment, it is necessary to evaluate several batches of the same oil.
04:23 --> 04:47
Speaker 1
Indeed, one of the key points of the evaluation is to properly characterize the essential oil, both in terms of the concentrations of the components present, and of the possible contaminants (such as pesticides) that may affect its toxicity. Just as extraction processes concentrate the compounds, they can also concentrate impurities like pesticides if the plant has been treated!
04:48 --> 05:13
Speaker 2
Also to note that at present little toxicological data is available on essential oils, so it's necessary to adapt to each substance and study its components for safety assessments. What further complicates safety evaluation is that several components may be common to multiple essential oils. This must be taken into account when several essential oils are mixed.
05:14 --> 05:33
Speaker 1
Thank you Marine. In the future, it will be worthwhile to generate toxicological data on essential oils because the toxicity of an essential oil is not necessarily the sum of the toxicities of its components. We invite you to learn more in the next episode of this topic planned for February.
05:34 --> 05:53
Speaker 2
Indeed, in the next discussion, we will go deeper into the toxicological assessment of an essential oil. In particular, we will see how to take into account the complex composition of essential oils and how to evaluate essential oils in a mixture. Thank you for listening and see you soon.
05:54 --> 05:55
Speaker 1
Thank you. Good bye.