I'm not a lawyer and I have gathered this information, below, as part of my studies, for information purposes only. If anyone finds any inaccuracies, or can add some information, please email me.
 

Aromatherapy Firm Loses Lawsuit for False Claims
Aroma Vera, one of the oldest and most-respected sellers of essential oils, had its company's claims hauled into court, and they lost.
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What legal issues are relevant to the practicing aromatherapist in the United States?
The FTC, not the FDA, may have dominion over the claims of aromatherapists and suppliers.
This section, below may be worthy of a printout for reference for anyone who considers themselves an aromatherapist or supplier, anyone who makes claims about EOs.

I was doing research on another subject, and discovered this
information, which I believe has dramatic impact on aromatherapy
claims. Seems there are felony prosecution ramifications to
making unsubstantiated claims. In searching The National Association
of Holistic Aromatherapy's site (NAHA),
and the Aromatherapy Registration Council (ARC)
guidelines, I find no reference to  ISO 14020-14025,
which leads me to believe, again <sigh> that these two
entities are clueless on more than one important legal fronts. It
would also be interesting to see if any of the 'schools'
that teach AT are clued in to this law. I would welcome any
corrections from these organizations and/or schools, and will post
their rebuttals here.

In addition, websites, brochures, advertisements and other claims
disseminated to the public would come under the scrutiny of the FTC, according
to the following information:

The United States Federal Trade Commission issued guidelines for the use of
environmental marketing claims. According to the FTC -- on which much of ISO
14020-14025 was based -- environmental advertising must be true, not
misleading, and substantiated. Unfair methods of competition in or affecting
commerce, and unfair or deceptive acts or practices in or affecting commerce are
against the law. The FTC code of regulations (Section 260, Subsection E) states
as follows:

    [A]ny party making an express or implied claim that represents an objective
    assertion about the environmental attribute of a product or package must, at
    the time the claim is made, possess and rely upon a reasonable basis
    substantiating the claim. A reasonable basis consists of competent and
    reliable evidence. In the context of environmental marketing claims, such
    substantiation will often require such competent and reliable scientific
    evidence.

The risk of making an improper environmental claim means running the risk of
violating federal advertising regulations.

What does this mean to you? Someone who makes a claim about their
aromatherapy abilities without having an independent third-party certification by law
must do the following:

    Specify the environmental improvement or attribute of the product or service.

    Never directly or by implication suggest an environmental improvement that
    does not exist.

    Never exaggerate the environmental benefit of an attribute or of a product or
    service to which a claim refers.

    Ensure the information is accurate.

    Ensure the information is not deceptive.

    Verify they can substantiate it (that is, prove that their claims are authentic).

    Use the claim in an appropriate context or setting.

    State specifically and clearly as to what particular environmental attribute the
    claim relates to.

    Ensure the claim is unlikely to result in misinterpretation.

    Make it meaningful in relation to the overall environmental impact of the
    product or service.

    Present the claim in a manner that clearly indicates the environmental claim
    and explanatory statement are read together.

    Never state the claim is endorsed or certified by an independent third-party
    organization when it has not been.
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What legal issues are relevant to the practicing aromatherapist in the United Kingdom?

Information can be found on these sites.
IFEAT -- International Federation of Essential Oils and Aroma Trade

Dear Readers, if you can supply me with any other information regarding consumer and legal issues in AT, please email me.