Determination of polyciclic aromatic hydrocarbons (PAH) by LC-FD as quality index in cofee brew samples

Polynuclear aromatic hydrocarbons (PAHs) are well-known environmental pollutants, which may be formed during the combustion of carbonaceous materials at high temperature. Owing to their mutagenic and carcinogenic potential, they have been determined in several matrices, particularly waters, soils, and sediments. Of prime concern is also their occurrence in numerous foods, especially the highly carcinogenic benzo-[a]pyrene as this compound has been reported in several foods. Hence, a total PAH intake through foods in Italy was estimated at 3 μg/day, with an intake of carcinogenic PAHs near 1.4 μg/day, which is quite high compared to the estimated intake through respiration (near 0.37 and 0.13 ng/day for total and carcinogenic PAHs, respectively). In fact, PAH presence in food may come from external contamination of the initial food matrix (mainly atmospheric deposition, root uptake, or contact with hydrocarbon-based materials) and/or from degradation of some food material during food processes involving elevated temperatures (especially drying, cooking, frying, roasting, and smoking). In particular, their presence in coffee has been related to the roasting step, transforming the green into the roasted bean. This technological treatment modifies coffee chemical composition with the production, changing or decomposition of several compounds. Despite quite low PAH concentrations (μg/kg) in foods, this is one of the major factors contributing to human cancer. Therefore, it is of prime importance to develop rapid and reliable analytical methods for their accurate determination in food items in order to estimate the total amount of human exposure to PAHs. This paper presents a rapid and simple method for extraction and analytical determination by HPLC-RF of 15 PAHs in coffee brew samples.