Have you ever come across a company selling essential oils claiming that their oils are cheap adulterations? This would be the only thing which could validate the contrary claims of purity being made by the zillions of companies. Early aromatherapy trainings were very heavy on possible therapeutic applications but very light on oils themselves. When aromatherapy began to explode during the nineteen eighties in the UK several people left their jobs (or were sacked in one case) with fragrance houses and started dealing in essential oils. As a consequence of their background they knew how to manipulate oils in the service of profit, this combined with their knowledge made many aromatherapists sitting ducks.
Over the past twenty years in the UK there have been several attempts to set up organisations to verify standards but some of these involved using a crook as an advisor. We had a well known scandal here in the UK. A consumer magazine investigated sandalwood oil. When it analysed some being sold by a chain of shops it was found to contain no sandalwood at all. The lady that owned the shops carried the can but the real culprit the supplier got away with it. This person has been selling fake sandalwood for at least 15 years and is still doing so. After numerous complaints he was expelled from a UK trade organisation where he was seen as a bit of a likeable rogue. He has the charm, the knowledge and people are taken in especially if I may say so, the ladies. Good conmen are always plausible. He has now bought a company which is still a member of the organisation that expelled him and his company is still selling adulterated oils.
Many companies which are members of the same organisation continue to make medical claims on websites and in printed literature. It is this irresponsible behaviour that invokes the scrutiny which could lead to legislation that restricts the availability of essential oils. This illustrates why Julia and I have never joined any aromatherapy trade organisation. I am not talking about the educational side of things - we do support the IFA which is not a trade association.
Being able to judge character is perhaps more important than all the technical stuff. If there was an easy or fool proof way to test oils for purity the marketwould not be flooded with cheap adulterated versions. As Rumi says it is only because there is real gold that people accept false coin.