Determination of Polycyclic Aromatic Hydrocarbons in food using Gas Chromatography equipped with mass spectrometry

Abstract

Due to the fact that fish, meat and chicken are an essential nutritional food for infants as well as an important component of adult nutrition, the contamination of theses commodities with residues of PAHs is a matter of serious concern. These residues in food are often due to either environmental contamination or via wrong cooking procedures. Egyptian Organization for Standardization and Quality specialized general standard for the food specifies the safety standards for dairy products and set out maximum limits for PAHs residues in food and feed quite similar with the EU- legislation issued in this regard.

The use of a multi-residue method is the most efficient approach to the analysis of PAHs in Food in terms of analysis costs and turnaround time. Most of the described methods include more steps and high consumption of various solvents and reagents. The use of the QuEChERS method followed by GC-MS found to be the best combination for the determination of PAHs residues in food because of high recovery, short time of analysis, low cost and safety. The analytical method that was quick, easy, cheap, effective, rugged, and safe (QuEChERS) for analysis of pesticide residues was used for extraction of PAHs in animal origin tissue (EN 15662:2008), in the follow-up study.

Chapter 5 Summary & conclusion

In this study, a fast and easy method for determination 16 EU PAHs in fish, meat and chicken using GC-MS for detection at the 2µg/kg limit of determination was developed. The development included both clean up and detection techniques. The QuEChERS method followed by GC-MS is found to be the best combination for determination of the 16 PAHs compounds based on high recovery, short time of analysis, low cost and safety. Most of evaluated compounds showed a recovery ranging from 70 to 120% with relative standard deviations of less than 25% indicating acceptable reproducibility.

The study also showed that the matrix effect of fish, meat and chicken caused enhancement during the detection of PAHs residues using GC-MS and recommend calculating the matrix effect to compensate the enhancement.

In addition, survey of PAHs contamination levels in grilled Meat, chicken and smoked fish investigated. The results found that benzo(a)pyrene concentration in charcoal grilled chicken ranged from 0.49-7.20μg/kg and 2.01 μg/kg mean concentration, while for charcoal grilled meat ranged from 2.42-4.48 μg/kg and 0.36 μg/kg mean concentration and from1.97 μg/kg to 4.87μg/kg for smoked fish. The summation of 16PAHsconcentrations in term of benzo(a)pyrene ranged from 0.03-10.65 μg/kg and mean concentration 3.03 μg/kg for charcoal grilled chicken, while for charcoal grilled meat from 0.10 to 6.49 μg/kg and mean concentration 1.13μg/kg and from 0.03 μg/kg to12.65 μg/kg for smoke fish.

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The current study also shows that food processing methods could effect on contamination of food with PAHs levels such as grilled meat and chicken where large reductions in residue levels using of electric grill instead of traditional charcoal grill was noticed where the level of contamination reduced by 100%.

The dietary exposure assessment is based on the occurrence data of PAHs concentration and consumption of the corresponding food categories. Ranges and sum of B(a)P, Σ7PAHs was calculated. The mean intake values obtained in this study were lower compared to estimates for EU countries; however, the results show that, for sum of seven carcinogenic PAHs in term of B(a)P, the intake may be significant and exceed the average value by 6.3 and 4.1 times for meat and chicken respectively.