Polycyclic Aromatic Hydrocarbons in Traditionally Used Medicinal Plants from Varna Region, Bulgaria

Extracts of medicinal plants are often used for preparation of food supplements, pharmaceutical products or for direct preparation of teas, but they may contain toxic substances, such as polycyclic aromatic hydrocarbons (PAHs). The content of PAHs was determined in Matricaria chamomilla L., Thymus serpyllum L., Tilia tomentosa Moench, Sambucus nigra L. and Achillea millefolium L., collected from urban and rural region near Varna, Bulgaria. The aim of this study was to compare the levels of PAHs in traditionally used medicinal plants from different regions to assess environmental pollution. Benzo[a]anthracene, chrysene, benzo[b]fluoranthene and benzo[a]pyrene are among the 16 priority pollutants pointed out by The United States Environmental Protection Agency. The PAH levels were determined in extracts of medicinal plants by GC-MS after purification. Chrysene was registered as most abundant compound in all the plant species investigated. Benzo[a]pyrene, identified by the International Agency for Research on Cancer (IARC) as carcinogenic to humans, was not detected in the samples analyzed. The levels of investigated PAHs were significantly higher in samples from areas with intensive traffic compared to samples from suburban areas. The sum of the four PAHs in all plant species were found in the range of 0.68 (Sambucus nigra L.) to 6.82 µg/kg dw (Tilia tomentosa Moench) and was below the permissible limit of the European commission.