Unwanted ingredients - Highly specific and sensitive method for the extraction and quantification of PFAS in everyday foods

Perfluorinated alkyl substances (PFAS) are anthropogenic substances and can only come from polluted sources. There are many classes of PFAS which can be transformed to perfluoalkyl carboxylic acids and perfluoroalkyl sulfonic acids in the environment. Once they are in this form they are environmentally mobile and extremely stable with half lifes of decades. These compounds are not innocuous and are implicated in causing many different diseases.In this publication a method for the extraction and quantitation of perflurocarboxylic acids and perfluorosulfonic acids, using high resolution liquid chromatography mass spectrometry (HRMS), is evaluated. The linearity, recovery and matrix effect are described and the method tested on tomato, strawberry and milk purchased from different locations. The C 8 PFAS – perfluorooctanoic acid and perfluorooctane sulfonic acid which were added to the Stockholm Convention list for restricted use in 2008 were not determined. However, the C 4 version – perfluorobutanoic acid was determined at different concentrations in all 3 matrices. The samples were sourced from different locations and had different packaging and therefore it is likely the contamination was from environmental sources such as bio-accumulation from groundwater or airborne particles.