Virgin olive oil (VOO) is considered a high-value vegetable oil which possesses a characteristic aroma, taste and color. Olive oil is produced by only mechanical methods, thus there is no use of chemicals during its production. Besides, unlike the other vegetable oils, olive oil can be consumed directly without further refining (Fitó et al., 2000). Virgin olive oil contains some minor compounds including tocopherols, sterols, carotenoids, squalene and phenolic compounds which have health-promoting attributes. A high consumption of virgin olive oil could reduce oxidative stress, prevent some cancer types, heart disease, and ageing (Nath and Nath 2000; Owen et al., 2000). Barbagallo et al. (2017) reported that olive oil has many phytochemicals including phenolic components and secoiridoids that exert antioxidant activities.

Innovative and healthy products attract consumers’ attention. One innovative product is flavored olive oils. Flavored olive oils are improved with healthy ingredients which make them preferable to consumers. Several materials are used to make flavored olive oils. These materials are essential oils, fruits, herbs, mushrooms, nuts, spices and vegetables (Sousa et al., 2015). These innovative oils are generally produced via the maceration method. In this method, flavoring materials are mixed with virgin olive oil and the mixture is left for a certain time, enabling the increase in some constituents such as aroma compounds and phenolics which exhibit antioxidant and antimicrobial properties (Moldão-Martins et al., 2004; Ayadi et al., 2009; Baiano et al., 2010; Jović et al., 2018). Beside aroma, these flavoring materials may contribute to a longer shelf-life for virgin olive oils due to their preventive effect from oxidation. In addition, some constituents, especially phenolics, contribute to human health (Baiano et al., 2010).

Phthalates are synthesized by a double-esterification mechanism of 1,2-benzenecarboxylic acid, and they are reported to have branched, apolar and linear components (Notardonato et al., 2018). The Environmental Protection Agency (EPA) classified phthalates as priority pollutants which endanger human health by carcinogenic effects, adverse reproductive effects, and by altering endocrine function (Cadogan, 2002; Rios et al., 2010). Phthalates are used in different materials such as polyvinyl chloride, polyvinyl acetate and polyester materials (Rios et al., 2010). In many previous studies associated with foods and phthalates, di (2-ethylhexyl) phthalate (DEHP), diisobutyl phthalate (DiBP), di-n-butyl phthalate (DnBP) benzylbutyl phthalate (BBP) were determined to be the most commonly identified phthalates (Tsumura et al., 2002; Jarošová et al., 2006; Fierens et al., 2012).

Phthalates have higher solubility in vegetable oils than in water, which makes them a risky food product. Therefore, the determination of the presence and amount of phthalates in vegetable oils is very important for human health and confidence (Cavaliere et al., 2008). Several studies have been conducted on the presence of phthalates in olive oil. DEHP, DnBP and BBP were identified in extra virgin olive oils, olive oils and olive pomace oils from the Italian market. Olive pomace oils contained higher concentration of phthalates, while lower amounts were detected in extra virgin oils (Cavaliere et al., 2008). DiBP, BBP and DEHP were determined as the most abundant phthalates in Sicilian virgin olive oils, while DiNP and DiDP were the most abundant in Molise olive oils (Mo Dugo et al., 2011). In another study by Nanni et al. (2011), the researchers demonstrated that DEHP and DINP were found at the highest levels among phthalates in extra virgin olive oils in Italy.

According to the legislation in this field, five phthalates are listed due to their potential health effects on humans including dibutyl phthalate (DBP), benzyl butyl phthalate (BBP), di(2-ethylhexyl) phthalate (DEHP), the sum of diisononyl phthalate (DINP) and diisodecyl phthalate (DIDP) with their specific migration limits as 0.3, 30, 1.5 and 9 mg/kg, respectively (EFSA 2005a; 2005b, 2005c, 2005d, 2005e; European Commission 2011). To the best of our knowledge, there is no information on phthalates in flavored olive oils. The aim of this work is to evaluate the presence of phthalates in flavored olive oils sold in Turkish markets, and to determine whether phthalate concentrations depend on the type of flavoring materials. The results will be useful for future studies regarding specific phthalate exposure from flavored olive oils.

Table 5 shows the phthalates found in flavored olive oils. In all analyzed samples BBP, DINP and DIDP were less than LOQ. In previous reports, DBP, BBP, DINP and DIDP were identified in olive oil samples marketed in Italy (Fusari and Rovellini, 2009; Mo Dugo et al., 2011).

The current study revealed that DEHP was present in 18 of 25 samples with a mean value ranging from < LOQ to 1.81±0.025 mg/kg. The oil sample flavored with bergamot (FOO3) included the highest level of DEHP at 1.81±0.025 mg/kg, followed by the oil flavored with mandarin (FOO11, 1.61±0.045 mg/kg). In this study, the concentration of DEHP in 5 of the 25 samples was past the substance migration limit (SML) (1.5 mg/kg) as determined by EU 2011/10 for this phthalate. In a study by Mo Dugo et al. (2011), the DEHP levels in all olive oil samples from 3 years were detected with mean values of 1.171, 1.935 and 0.445 mg/kg, respectively (Mo Dugo et al., 2011). The DEHP concentrations were also lower than extra virgin olive oils in glass and in tinplate (Nanni et al., 2011). No phthalates were detected in sample FOO14 (flavored with sumac), FOO15 (flavored with green pepper), FOO16 (flavored with mandarin basil), FOO17 (chili pepper), FOO21 (rosemary), FOO24 (basil) or FOO25 (rosemary).

As shown in Table 5, DBP was present in nine of 25 samples with a mean value ranging from < LOQ to 0.27±0.015 mg/kg. In a study by Sungur et al. (2015), DBP concentrations were 0.117-1.418 mg/kg for olive oils and 0.102-1.048 mg/kg for virgin olive oils. In our study, the concentration of DBP did not exceed the substance migration limit (SML) (0.3 mg/kg) as set by EU 2011/10. The DBP concentrations in virgin olive oils in the current study were similar to those reported by Sungur et al. (2015).

The results obtained showed that a relation could be found between phthalate concentrations and flavoring materials. In a survey work by Cao et al. (2015), the phthalate contents in different food stuffs were investigated and DEHP was detected at the highest levels in the herbs and spices samples in almost all food stuffs. In another study by Ning et al. (2017), the concentration of DEHP in raw green pepper ranged from 1.83 to 5.95 mg/kg, which exceeded the legislated limit by EU 2011/10. The findings in the previous reports are considered useful to explain the high DEHP concentrations in flavored olive oils with herbs as observed in our study. In our study, the DEHP concentrations were 1.81 mg/kg for olive oil flavored with bergamod, 1.59 mg/kg for olive oil flavored with rosemary, and 1.59 mg/kg for olive oil flavored with black pepper. In a study by Di Bella et al. (2018), in which phthalates were determined in Tunisian culinary spices and herbs, DEHP concentrations in spices and herbs including caraway, black pepper, mint, oregano, coriander, thyme, rosemary, fennel, verbena, and laurel were found to range from 0.6 to 1.18 µg/kg.

The results from our study regarding phthalates in flavored oils indicated that 6 of 25 virgin olive oil samples flavored with different materials included DEHP (1.45±0.03 - 1.81±0.025 mg/kg), and these concentrations exceeded the SML set by EU 2011/10 regulation (1.5 mg/kg). In this study, DBP concentrations in all analyzed samples did not exceed the migration limit (SML) (0.3 mg/kg) of EU 2011/10, while BBP, DINP and DIDP were found to be less than their LOQ in all analyzed samples. However, from a food safety perspective for phthalates, seven flavored olive oil samples contained no residue of phthalates. The findings of this study are useful for the flavored olive oil producers and oil industry and will be a guide for a phthalate-free flavored olive oil production.