## 3 Results and Discussion
### Physicochemical Characteristics of Cold-Pressed Camelina Oils
#### 3.2.4 Polycyclic Aromatic Hydrocarbons Content  
PAHs are hazardous, mutagenic, and carcinogenic chemical contaminants generated in vegetable oils during industrial production and from oil plants exposed to industrial and vehicular emissions. Technological processes at high temperatures, such as oilseed drying and roasting, solvent extraction, and long-duration frying, favor the formation of lipophilic PAHs in edible oils. Due to the lipophilic nature of PAHs, edible oils and fats can be the main source of these contaminants, and their analysis is necessary [53]. In this study, B(a)P, Chry, B(a)A, and B(b)F were determined and summed as \(\mathrm{\sum}\)4 PAHs to enable comparison with EU Regulation No 835/2011 [16] on contaminants limits in food, where B(a)P and \(\mathrm{\sum}\)4 PAHs are limited to 2.0 \(\mathrm{\SIUnitSymbolMicro g}\)/kg and 10.0 \(\mathrm{\SIUnitSymbolMicro g}\)/kg, respectively. The obtained results of each PAH content in the commercial CPCO samples are presented in Table 4. All analyzed oil samples had levels of B(a)P (0.13-1.90 \(\mathrm{\SIUnitSymbolMicro g}\)/kg) and \(\mathrm{\sum}\)4 PAHs (0.72-7.22 \(\mathrm{\SIUnitSymbolMicro g}\)/kg) below the maximum imposed by the EU Regulation No 835/2011 [16]. It is noteworthy that B(a)A was the analyte determined with the highest values in the interval 0.27-3.07 \(\mathrm{\SIUnitSymbolMicro g}\)/kg. Interestingly, CPCO5 contained the highest B(a)A, whereas CPCO6 was the richest source of B(a)P, Chry, and B(b)F. Probably, the contact of _Camelina sativa_ seeds with polluted surroundings and the drying process at high temperatures before CPCO6 pressing, by direct contact with combustion gases or migration of these contaminants to seeds from packaging bags, can cause PAH formation in the highest amounts [53; 54]. Moreover, insignificant differences in concentrations of each measured PAH were observed between CPCO1, CPCO7, and CPCO8 (Duncan test, Table 4). Regarding the results of B(a)P, Chry, B(a)A, B(b)F, and \(\mathrm{\sum}\)4 PAHs in eight commercial CPCO samples available on the Polish market, these were somewhat lower than values (B(a)P = 0.21-1.00 \(\mathrm{\SIUnitSymbolMicro g}\)/kg, Chry = 0.21-4.40 \(\mathrm{\SIUnitSymbolMicro g}\)/kg, B(a)A = 0.09-1.94 \(\mathrm{\SIUnitSymbolMicro g}\)/kg, B(b)F = 0.05-1.89 \(\mathrm{\SIUnitSymbolMicro g}\)/kg, and \(\mathrm{\sum}\)4 PAHs = 0.56-9.23 \(\mathrm{\SIUnitSymbolMicro g}\)/kg) reported by [PERSON] et al. [15] in two amelina seeds oils prepared by artisans at small-scale agricultural companies in Lithuania. Furthermore, amelina oil pressed from untreated and treated amelila seeds powder with hot air and steamed with an electric steam revealed a similar but higher amount of B(a)P (about 0.8 \(\mathrm{\SIUnitSymbolMicro g}\)/kg) than investigated CPCO samples (except CPCO6). However, puffing pretreatment of amelila seeds powder significantly increased the B(a)P content to 1.3 \(\mathrm{\SIUnitSymbolMicro g}\)/kg in oil [55]. Expectedly, much higher amounts of B(a)P (6.51 \(\mathrm{\SIUnitSymbolMicro g}\)/kg) and \(\mathrm{\sum}\)4 PAHs (35.99 \(\mathrm{\SIUnitSymbolMicro g}\)/kg) were determined in crude oil pressed from roasted camellia seeds at 100 \({}^{\circ}\)C for 30 min by using a low-temperature screw press [54]. Consequently, concentrations of B(a)P (0.86-7.44 \(\mathrm{\SIUnitSymbolMicro g}\)/kg) and \(\mathrm{\sum}\)4 PAHs (5.21-41.32 \(\mathrm{\SIUnitSymbolMicro g}\)/kg) changed in each stage of camellia oil refining, but decoloration caused the highest decrease in these contaminations. This suggests that high-temperature reactions during seed preparation (roasting, crushing), oil pressing, and refining processes (mainly decoloration), as well as absorbent used in filtration and decolorization, significantly affected the PAH levels in the obtained camellia oil [54].