Determination of selected dichloroanilines and phthalates in lyophilised mussels samples with ultra-high performance liquid chromatography-tandem mass spectrometry after QuEChERS clean-up

ABSTRACT

Mussels, a marine filter organism, constitute a food product and an established sentinel organism for marine pollution. An analytical method following a QuEChERS extraction and clean-up protocol has been developed for the determination of phthalic acid esters (PAE), including di-n-octyl phthalate (DnOP), di-(2-ethyl hexyl) phthalate (DEHP), butyl benzyl phthalate (BBP), di-methyl phthalate (DMP) and di-n-butyl phthalate (DnBP), as well as 3,4-dichloroaniline and 3,5-dichloroaniline in lyophilised mussels samples. A gradient elution program starting from 40% A (methanol-0.1% formic acid) – 60% B (H₂O-0.1% formic acid) up to 100% A was applied, with a total duration of 15 min, at a flow rate of 200 μL min⁻¹ using a 1.8 μm particle size C18 analytical column. All target analytes were detected with a triple quadrupole MS, using electrospray ionisation (ESI) in positive ionisation mode, in SRM mode under optimised conditions. Sample preparation consisted of lyophilisation of the mussels sample and grinding, followed by a QuEChERS (Quick, Easy, Cheap, Effective, Rugged, Safe) protocol. Among the different dispersants evaluated for sample clean-up effectiveness, primary secondary amine (PSA) was found to be the most efficient. Results indicated good chromatographic separation, fast sample preparation procedure, low LODs and LOQs, good trueness expressed as recovery and good precision as evaluated by RSD. In the mussels samples examined DEHP was the most abundant PAE, reaching a maximal concentration of 280 μg/kg of lyophilised weight whereas the levels of DnBP were at approximately 36% of the legal migration limit in foods determined by the EU.

Graphical Abstract

KEYWORDS:

• Endocrine disrupting compounds
• UHPLC-MS
• mussels