Abstract

Drinking straws contact the oral cavity directly, and children use them routinely, raising concern about exposure to various chemicals. In this pilot study, six paper and three plastic straws were immersed in human saliva for 10 minutes, and five per- and polyfluoroalkyl substances and two phthalates were quantified by liquid chromatography–tandem mass spectrometry and gas chromatography–mass spectrometry, respectively. Perfluorohexane sulfonic acid, perfluorooctanoic acid, and perfluorononanoic acid were below the limit of detection (LOD) in all samples; perfluorooctanesulfonic acid was above the LOD in the procedural blank and one paper straw, and perfluorodecanoic acid was above the LOD in two straw samples. Di-n-butyl phthalate, which was below the LOD in the blank, was detected up to 30.097 µg/L in paper straws and 45.974 µg/L in plastic straws. Di(2-ethylhexyl) phthalate was elevated in the procedural blank (14.240 µg/L), precluding quantitative comparison between materials; nevertheless, four paper straws and one plastic straw exceeded this background. This pilot study highlights the need for methodological refinement and further investigation.  

• Keywords: Endocrine disrupting compounds; Phthalates; PFAS; Saliva exposure; Straws