The development of an analytical method to evaluate the nitrosamine profile in cooked ham with different preservatives and in rat feces fed with them

Nitrosamines are classified as carcinogenic chemicals and are a growing public health concern. They have been widely documented in food, which is the main route of human exposure. However, there is little research on their appearance in biological samples, such as feces. This study presents a methodology for determining the concentration of 14 nitrosamines in cooked hams and fecal samples obtained from animals fed with them, allowing changes in the nitrosamine concentration during digestion to be identified. The novelty of this research lies in the fact that it is the first to evaluate whether incorporating polyphenols into cooked ham influences the levels of NAs in feces using an animal model. The proposed analytical method based on ultrasound-assisted extraction of the nitrosamine high-performance liquid chromatography and mass spectrometry using a triple quadrupole achieved low limits of quantification (in the 0.44-47 ng g^-1 range), good precision (coefficient of variation of less than 12.4%), and trueness for both matrices. A total of 68 samples were analyzed, with five nitrosamines detected in the cooked ham samples and seven in the fecal samples. Statistical analysis revealed that the nitrosamine profile mainly depended on the biological matrix. While the preservative did not significantly affect the nitrosamine profile in cooked ham, it did modulate the nitrosamine concentration in feces. Specifically, diets containing polyphenols significantly reduced fecal nitrosamine levels compared to diets containing nitrites, suggesting a possible protective role against the formation of these compounds in the gut.