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Određivanje prisustva polihlorovanih bifenila je značajno jer oni spadaju u perzistentne organske zagađivače, koju su dobijeni sintetičkim putem. Ova jedinjenja se koriste za kondenzatore i transformatore, i nakon toga akomuliraju se u sedimentima, a zbog lipofilnih osobina ove kancerogene i mutagene supstance dospevaju u tkivu riba. Zbog štetnog uticaja po ljudsko zdravlje i životnu sredinu monitoringu prisustva PCB-a u svim vrstama riba se daje na važnosti. Metode pripreme uzorka su validirane za analizu indikatorskih PCB-a u ribama oslića korišćenjem gasne hromatografije-masene spektrometrije (GC/MS) za kvantifikaciju. Analizirani su uzorci dve vrste riba iz porodice Merlucciidae, i to Merluccius hubbsi i Merluccius senegalenensis. Obzirom da u matriksu prisutne koektrakcione supstance mogu oštetiti GC koluni, kao i interferirati tokom detekcije ispitano je poređenje tri tipa sredstva za prečišćavanje ekstrakta. Disperzni sorbenti koji su korišćeni su: 1) PR Florisil 500 mg; 2) MgSO4, C18, PSA i dodatno prečišćavanje eluiranjem na 100 mg C18 ketridžu i 3) dodatno eluiranje na 200 mg C18. U prvom i drugom slučaju je dobijen zadovoljavajući recovery od 73.5-86.2%, odnosno 71.3-86.8 %, respektivno. Dok su u trećem slučaju korišćenjem ketridža 200 mg/3 ml C18 srednji recovery su bili nezadovoljavajući u opsegu od 45.0-52.3%, ali su hromatogrami bili bez interefrirajućih supstanci, što je dovelo do zadržavanja i ispitivanih PCB. Tako da je treći postupak pripreme odbačen za određivanje realnih uzoraka. Metode su validovane kroz linearnost, preciznost, specifičnost, tačnost i limit kvantifikacije. Limiti kvantifikacije za indikatore PCB su 3 ng/g računato na vlažnu masu. U svim ispitanim uzorcima vrednosti PCB-a su bile ispod LOQ. Uredbom Komisije (EU) br. 1259/2011 utvrđen je maksimalni nivo za zbir šest markera ili indikatorskih PCB-a (PCB 28, 52, 101, 138, 153 i 180) u mišićnom mesu ribe u vrednosti od 75 ng/g (v.m.). Obe metode pripreme su potvrđene zadovoljavajućim rezultatom za PCB 153 korišćenjem sertifikovanog referentnog materijala - masne ribe (Fapas, UK), pri čemu su dobijene vrednosti 24.2 ng/g i 26.4 ng/g, respektivno, a tačna vrednost je bila 28.0 ng/g sa dozvoljenim opsegom 15.7-40.3 ng/g. Determination of the presence of polychlorinated biphenyls has become important because they belong to the persistent organic pollutants, which are obtained synthetically. These compounds are used for capacitors and transformers, and after that they accumulate in sediments, and due to lipophilic properties, these carcinogenic and mutagenic substances reach the fish tissue. Due to the detrimental impact on human health and the environment, monitoring the presence of PCBs in all fish species is given importance. Sample preparation methods were validated for the analysis of the indicator PCBs in the hake fish using gas chromatography-mass spectrometry (GC/MS) for quantification. The analyzed samples were from two species of fish from the family Merlucciidae, namely Merluccius hubbsi and Merluccius senegalenensis. Since the co-extractants present in the matrix can damage GC columns, as well as interfere during detection, a comparison of three types of extract cleanup was examined. Dispersive sorbents used are: 1) PR Florisil 500 mg; 2) MgSO4, C18, PSA and additional clean-up by elution on a 100 mg C18 cartridge and 3) additional elution at 200 mg C18. In the first and second cases, a satisfactory recovery of 73.5-86.2% and 71.3-86.8%, respectively, was obtained. While in the third case using a 200 mg/3 ml C18 cartridge, the mean recovery was unsatisfactory in the range of 45.0-52.3%, but the chromatograms were free of interfering substances, which led to retention and tested PCBs. Thus, the third preparation procedure was rejected for the determination of real samples. The methods Determination of the presence of polychlorinated biphenyls has become important because they belong to the persistent organic pollutants, which are obtained synthetically. These compounds are used for capacitors and transformers, and after that they accumulate in sediments, and due to lipophilic properties, these carcinogenic and mutagenic substances reach the fish tissue. Due to the detrimental impact on human health and the environment, monitoring the presence of PCBs in all fish species is given importance. Sample preparation methods were validated for the analysis of the indicator PCBs in the hake fish using gas chromatography-mass spectrometry (GC/MS) for quantification. The analyzed samples were from two species of fish from the family Merlucciidae, namely Merluccius hubbsi and Merluccius senegalenensis. Since the co-extractants present in the matrix can damage GC columns, as well as interfere during detection, a comparison of three types of extract cleanup was examined. Dispersive sorbents used are: 1) PR Florisil 500 mg; 2) MgSO4, C18, PSA and additional clean-up by elution on a 100 mg C18 cartridge and 3) additional elution at 200 mg C18. In the first and second cases, a satisfactory recovery of 73.5-86.2% and 71.3-86.8%, respectively, was obtained. While in the third case using a 200 mg/3 ml C18 cartridge, the mean recovery was unsatisfactory in the range of 45.0-52.3%, but the chromatograms were free of interfering substances, which led to retention and tested PCBs. Thus, the third preparation procedure was rejected for the determination of real samples. The methods were validated through linearity, precision, specificity, trueness and quantification limit. The quantification limits for PCB indicators were 3 ng/g wet weight. In all tested samples, PCB values were below LOQ. Commission Regulation (EU) No 1259/2011 established a Maximum level for sum of the six marker or indicator PCBs (PCB 28, 52, 101, 138, 153 and 180) in muscle meat of fish at a value of 75 ng/g (w. w). Both preparation methods were confirmed by satisfactory results for PCB 153 using certified reference material - fatty fish (Fapas, UK), with values of 24.2 ng/g and 26.4 ng/g, respectively, and the assigned value was 28.0 ng/g with a permissible range of 15.7-40.3 ng/g. Zbornik radova i kratkih sadržaja |
