Detection of migration of phthalates from agglomerated cork stoppers using HPLC-MS/MS.

Agglomerated stoppers are manufactured from natural cork granules and adhesives. Esters, such as phthalates and adipates, are commonly used in adhesives at concentrations of typically 2-5%. Because of this, and regarding consumer safety, it is necessary to ensure that these compounds do not migrate into the beverage where the cork stopper is used. A reversed-phase high performance liquid chromatography method with tandem mass spectrometry detection is developed for the separation of nine phthalates into 12% ethanol, used as simulant of alcoholic beverages. The chromatographic separation was carried out with a Luna C18 (2) HSTcolumn (50 × 3.0 mm, 2.5 µm) with a gradient elution of water/methanol with 0.1% acetic acid at 300 µL min(-1). The method was validated for four selected phthalates: di-butylphthalate, di-isononylphthalate, di-isodecylphthalate, and butyl-benzyl phthalate, with recoveries ranging between 95% and 112% and intralaboratory precision (RSD) between 5 and 14%, depending on the phthalate. The lowest quantification limit, 0.15 mg kg(-1), was achieved for di-butylphthalate. Nevertheless, in all cases, the limits obtained guarantee the method utility if restriction limits set in Commission Regulation No 10/2011 for plastic materials are taken into account.

Validation of a liquid chromatography-mass spectrometry method for determining the migration of primary aromatic amines from cooking utensils and its application to actual samples.

Many cooking utensils are made of nylon, a material that may incorporate azodyes and where primary aromatic amines (PAAs) are the starting substances. Moreover, aromatic amines may also be present as technical impurities. Another source of PAAs could be aromatic isocyanates used as monomers in the production of polyurethanes. The aim of this work was to validate a simple LC-MS/MS method for the determination of eight primary aromatic amines (m-phenylenediamine, 2,6- and 2,4-toluenediamine, 1,5-diaminonaphthalene, aniline, 4,4'-diaminonaphenylether, 4,4'-methylenedianiline and 3,3'-dimethylbenzidine) in the aqueous food simulant 3% acetic acid (w/v). The detection limits calculated were adequate with respect to present legislation. The method was validated at four concentration levels (2, 5 10 and 20 microg kg(-1)). Global internal reproducibility was in the range 5.6-21.4% (RSD(R)) depending on the compound and concentration. Mean recoveries for all levels varied between 89 and 100%, depending on the amine. A total of 39 samples of cooking utensils were analyzed using the described method and the results obtained after the third migration test were not compliant in approximately half of the samples.