Detection of microplastic residues - developing a method for phthalates in honey

Abstract

In this pilot study, a method for the determination of phthalates in honey was developed. Th e following phthalates are included: dimethyl phthalate, diethyl phthalate, di-isobutyl phthalate, di-n-butyl phthalate, bis(2-ethylhexyl) phthalate, and di-(n-octyl) phthalate. For the preparation of the samples, the method of liquid-liquid extraction with hexane with an ultrasonic bath was used. Th e analysis of the prepared samples was performed using gas chromatography and a mass detector. Th e method is reliable, sensitive, and reproducible with a detection limit of 0.28 - 1.38 μg/kg. Th is paper presents the results of testing samples of honey stored in glass and plastic packaging for three years in order to determine the migration of phthalates. Dimethyl phthalate was not found in the tested samples stored in plastic and glass packaging. Diethyl phthalate was not found in samples stored in glass packaging while the concentration of diethyl phthalate in samples from plastic packaging was 3.34 μg/kg. Th e concentrations of diisobutyl phthalate, di-n-butyl phthalate and bis(2-ethylhexyl) phthalate, determined in samples from glass packaging were 5.32, 1.32 and 4.45 μg/ kg, and in honey samples from plastic packaging 15.84, 16.01 and 14.44 μg/kg. Concentrations of di-(n-octyl) phthalate were less than the LOQ in both types of samples.