Revised USP Chapter <561> Articles of Botanical Origin

A revised version of USP chapter <561> Articles of Botanical Origin (ABOs) has been published in the Pharmacopeial Forum (PF) 51(4). The comment deadline is 30 September 2025.

Proposal to add a test method for Polycyclic Aromatic Hydrocarbons (PAHs)

It is being proposed to add a test method (GC-MS) to determine polycyclic aromatic hydrocarbons (PAHs). PAHs are aromatic compounds consisting of two or more fused aromatic rings made up of carbon and hydrogen. They have been extensively studied since it was discovered that some of them are genotoxic and carcinogenic, such as benzo[a]pyrene. Recent studies have shown that some medicinal plants can be contaminated with PAHs, which can arise due to contamination either during the post-harvest processing or by environmental sources, because the lipophilic properties of these compounds can allow for their adsorption onto atmospheric particles as well as direct deposition in sediments, soils, and plants. Due to their high surface areas, ABOs are susceptible to environmental contamination by PAHs, and drying processes can potentially contribute to this contamination. The European Food Safety Authority Panel on Contaminants in the Food Chain (EFSA CONTAM Panel) concluded that four PAHs (benzo[a]pyrene, chrysene, benz[a]anthracene, and benzo[b]fluoranthene) serve as indicators of the presence of any PAHs in food. Thus, based on the European Commission Regulation 2015/1933, the USP proposes the following Acceptance Criteria:

• Benzo[a]pyrene: max 10.0 ppb
• Sum of benzo[a]pyrene, chrysene, benz[a]anthracene, and benzo[b]fluoranthene: max. 50.0 ppb

For more information please visit the Pharmacopeial Forum online.