New Ph. Eur. Chapter on Essential Oils

The general Ph. Eur. monograph on Essential oils has been published for comment in the recent issue of Pharmeuropa (32.2). The monograph has undergone complete revision. As basis for the elaboration of monographs on essential oils, a new Ph. Eur. chapter 5.30. Monographs on essential oils is proposed in addition. The public deadline is 30 June 2020.

Contaminants in Essential Oils and Skip Testing

Herbal drugs used for the preparation of essential oils have to comply with the requirements of any relevant monograph in the Ph. Eur. (for example general Ph. Eur. Monograph Herbal Drugs). In addition, the draft monograph on essential oils prescribes limits for the following tests on contaminants:

Heavy metals (Ph. Eur. 2.4.27)

• cadmium: maximum 1.0 ppm;
• lead: maximum 5.0 ppm;
• mercury: maximum 0.1 ppm.

Where necessary, limits for other heavy metals may be required.

Pesticide residues (Ph. Eur. 2.8.13), Aflatoxin B1 (Ph. Eur. 2.8.18) and Microbiological quality (Ph. Eur. 5.1.4 or 5.1.8): Where justified and authorized, individual testing of every batch may not be necessary.

According to the proposed new Ph. Eur. chapter 5.30. Monographs on essential oils, the "risk of the presence of contaminants in essential oils is closely linked to the type of contaminants, the origin of the plant material used for production and the production processes". However, contaminants such as heavy metals, pesticides, and aflatoxins are not considered a critical issue for essential oils. They need to be considered in individual cases based on a risk assessment. In particular, the risk is higher for cold-pressed essential oils than for distilled ones.

In general, Ph. Eur. chapter 2.8.13. Pesticide residues is applicable to essential oils. "Nevertheless, it has been shown that the levels of pesticides present in essential oils obtained by distillation rarely exceed the prescribed limits, which may justify skip testing".

More information can be found on the Pharmeuropa website.