Rapid qualitative analysis of phthalates added to food and nutraceutical products by direct analysis in real time/orbitrap mass spectrometry

A recent food safety issue involves the contamination of a broad range of food and nutraceutical products from Taiwan with industrial plasticizers. Among the suspected contaminants are selected phthalic acid esters, such as benzyl butyl phthalate, dibutyl phthalate, diisobutyl phthalate, di-2-ethylhexyl phthalate, di-n-octyl phthalate, diisononyl phthalate, and diisodecyl phthalate. Described in this study is an analytical method to rapidly qualitatively analyze these compounds in a wide variety of food and nutraceutical matrices suspected in this crisis. The method utilizes direct analysis in real time (DART) ionization coupled to a Thermo Exactive orbitrap mass spectrometer. The method is shown to be capable of detecting these compounds at levels greater than 1.0 μg/mL in all food products examined and 0.5 μg/mL in most of the samples tested. In the nutraceutical samples tested, the compounds were detected at levels of 50 μg/g for all samples with some detected as low as 1.0 μg/g.