Simultaneous determination of legacy and emerging organophosphorus flame retardants and plasticizers in indoor dust using liquid and gas chromatography–tandem mass spectrometry: method development, validation, and application
In the present study, an analytical method has been developed and validated for the simultaneous detection and quantification of 19 PFRs (14 legacy organophosphorus flame retardants (PFRs) and 5 emerging PFRs (ePFRs)) and 20 plasticizers (7 legacy plasticizers (LPs) and 13 alternative plasticizers (APs)). Sample preparation was based on the combination of previously validated analytical protocols including ultrasonic extraction and Florisil fractionation/cleanup. The analysis was performed by using liquid chromatography–tandem mass spectrometry (LC-MS/MS) for all targeted compounds, except for bis (2-ethylhexyl) phthalate (DEHP) and bis (2-ethylhexyl) terephthalate (DEHT), for which the separation of the isomers resulted in more favorable gas chromatography–electron ionization–mass spectrometry (GC-EI-MS). The new method was in-house validated by applying two levels of fortification in dust. The achieved linearity (R2) ranged between 0.993 and 0.999. Limits of detection and quantification (LODs and LOQs) ranged between 1 and 265 ng/g and between 1 and 870 ng/g for all analytes, respectively, except for DEHP and DEHT, for which relatively higher LODs (665 and 1100 ng/g, respectively) and LOQs (2100 and 3500 ng/g, respectively) were observed. Accuracy ranged between 75 and 125% for most of the targeted analytes, and repeatability was good with relative standard deviation (RSD) < 15% for most compounds. Finally, the method was applied for the determination and quantification of the targeted chemicals in house dust samples (n = 10) from the megacity of Guangzhou (China). Median values ranged from 3 to 210 ng/g for PFRs, from 4 to 165 ng/g for ePFRs, from 30 to 100,000 ng/g for LPs, and from 6 to 34,000 ng/g for APs. Main contributors to the total contamination were LPs 63% and APs 37% in total plasticizers, whereas PFRs and ePFRs contributed 90% and 10% in total flame retardants.
KeywordsSimultaneous determination Organophosphorus flame retardants Plasticizers Indoor dust Liquid chromatography Tandem mass spectrometry
The authors would like to thank Dr. Maarten Degreef for offering valuable guidance to the method optimization steps, Dr. McGrath for contributing in language revision and all dust sample donors from China. Dr. Christina Christia acknowledges a doctoral fellowship BOF DOCPRO 3 from the University of Antwerp. Dr. Giulia Poma acknowledges a post-doctoral fellowship from the University of Antwerp. Dr. Bin Tang and Dr. Shan-Shan Yin acknowledge research scholarship (201704910738 and 201706320119, respectively) provided by the China Scholarship Council for their research stays at the University of Antwerp.
The present work was supported by the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program (No. 2017BT01Z134).
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
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