“…[1][2][3] When parabens are present in high concentrations in the dermis, they may accumulate in the human body tissues in a similar way to other lipophilic compounds, which are bioaccumulative, or they may induce allergic dermatitis in sensitive individuals. 3,4 Although the use of parabens is regulated, traces concentrations of unhydrolyzed parabens have been determined in different biological samples, including plasma, 5 breast milk, [6][7][8][9] ovarian tissues, 10 urine, 4,7,[11][12][13][14] and serum 4,7,13,15 by chromatographic or electrophoresis techniques. Biological samples may not be introduced in their nature state in chromatographic systems, due to their endogenous compounds, mainly the proteins that can: (i) suppress the ionization of analytes, during the ionization process (liquid chromatography-mass spectrometry (LC-MS) analysis); (ii) co-elute with analytes, during the chromatographic separation; or (iii) adsorb irreversibly in analytical column.…”