Determination of the levels and distributions of polycyclic aromatic hydrocarbons in raw milk

Polycyclic aromatic hydrocarbons (PAHs) are organic compounds with carcinogens and other toxic effects resulting from incomplete combustion of organic compounds. PAHs occur in soil, air, water, and food. PAHs are also commonly found in milk as a ubiquitous lipophilic organic pollutant. In this thesis study, 16 PAH [Naphthalene (Np), Acenaphthene (Anp), Florene (Flr), Phenanthrene (Phe), Floranthene (Flu), Anthracene (An), Pyrene (Py), Chrysene (Chr), Benzo(a)anthracene (BaA), Benzo(b)fluoranthene (BbF), Benzo(k)fluoranthene (Bkf), Banzo(a)pyrene (BaP), Indeno(1,2,3-cd)pyrene (IcdP), Dibenzo(a,h)anthracene (DahA), Benzo(g,h, I)perylene (BghiP)] compounds were analyzed by GC-MS device and their amounts, which are the dominant PAH compounds were determined in raw cow's milk. It has been investigated whether the PAH levels of milk samples taken from Kastamonu and the surrounding provinces with similar ecological and climatic characteristics (Karabük, Bolu, Bartın, Çankırı, Zonguldak) are statistically significantly different from each other and the risks that may occur in terms of health have been evaluated. Samples were obtained directly from the same milk collection centers and producers twice, in January when air pollution is high in the region and in June when air pollution is low. In 72 milk samples examined, the least common PAH compound was Flu and BaP with two samples, while Np was the most common with 72 samples. Also, Np is the only compound found in all samples. The average of the total PAH amounts of all samples was determined as 121.9±37.6 μg/kg. The highest Total PAH content was found at 231.5 μg/kg in a sample (KRO2) taken from Karabuk province in January. The lowest Total PAH content was found at 45.9 μg/kg in a sample (KSH1) taken from Kastamonu province in June. In our study, BaP, which was classified as Group 1 Carcinogen in the International Agency for Research on Cancer (IARC) classification, was detected in two samples. These samples are; KRO6 coded sample taken from Karabük in January and ÇO1 coded sample taken from Çankırı in January. These BaP concentrations did not exceed the detected maximum limit (infant and child complementary foods maximum limit; 1 μg/kg). It was determined that the PAH4 amounts in 41 of 72 samples (23 in January and 18 in June) were above the maximum PAH4 limit (1 μg/kg) for infant and child complementary foods. In addition, our study determined a positive and significant relationship between the amount of fat in milk samples and the amount of PAH4 (p<0.05). While Bolu was the province where the PAH4 limit was exceeded the least with two samples, Karabük was the area where this limit exceeded the most with ten samples. Also, the highest PAH4 concentration (92 μg/kg) belongs to the sample (KRO6) taken from Karabuk province in January. The reason for the high incidence and the high concentrations of PAH4, BaP, and Total PAH in Karabük is thought to be due to the fact that there is a factory with a coke oven in the center of Karabük where the samples are collected. From the results of our study, it has been revealed that there is a health risk in terms of PAH compounds in milk, which can be considered as baby and child supplementary food and consumed by a significant part of society. PAHs, which can negatively affect human health in the long term, can cause cancer, deterioration of the immune system and hormones. In the samples examined, those who exceeded the limit determined for infant and child supplementary foods for PAH4. Since exceeding the limit may cause health risks, it is thought that the authorities should take measures in this regard and spread these measures throughout the country. Primarily in provinces with high environmental pollution, new studies should be carried out; legislation should be established to reduce pollution, and public awareness should be raised.