Polycyclic aromatic hydrocarbons in traditional Chinese medicines: an analytical method based on different medicinal parts, levels, distribution, and sources

Abstract

Herein, we describe a rapid, easy, and cost-effective high-performance liquid chromatography method using UV and fluorescence detectors for the simultaneous analysis of 16 polycyclic aromatic hydrocarbons (PAHs) in traditional Chinese medicines (TCMs). Pretreatment involved different extraction methods depending on the different medicinal parts, and was followed by silica gel purification. The method was validated and used to assess PAHs contamination in 32 TCMs. In the samples analyzed, all 16 PAHs were present. Their total contents ranged from 19.5 to 1614.1 μg kg⁻¹. Among all PAHs studied, phenanthrene was the most common and serious contaminant, followed by fluorene and fluoranthene. Leaves had the highest levels of the 16 PAHs, followed by roots and stems, seeds, flowers, and fruits. The diagnostic ratios and principle component analysis showed that the main sources of PAHs in TCMs were both pyrogenic and petrogenic. Furthermore, PAHs in roots and stems primarily originated from wood or coal combustion, as reported for the first time. Our results suggest that PAHs contamination in TCMs is widespread, and that the proposed method may be a useful tool for quality control of PAHs in TCMs, and for determining their potential health risks.