Identification of Three Novel Chloroalkyl Organophosphate Triesters in House Dust Using Halogenation-Guided Nontarget Screening Combined with Suspect Screening

Several haloalkyl organophosphate
triester (OPTE) flame retardants
have been restricted in some countries due to their potential health
risks, but the usage of alternative haloalkyl OPTEs is of concern.
In this study, we comprehensively screened for haloalkyl OPTEs in
house dust using high-resolution mass spectrometry. Through halogenation-guided
nontarget screening, a rare chloroalkyl OPTE, diethylene glycol bis­(bis­(2-chloroisopropyl)­phosphate)
(DEGBBCPP), was unequivocally identified (Level 1) in house dust of
Beijing, North China. In addition, by screening a suspect list of
61 haloalkyl OPTEs from the EPA’s CompTox Chemicals Dashboard,
we tentatively identified diethylene glycol bis­(bis­(2-chloroethyl)­phosphate)
(DEGBBCEP) and ethylene bis­[bis­(2-chloroethyl)­phosphate] (EBBCEP)
(Level 2). DEGBBCPP was detected in all 45 house dust samples, and
the median concentration was 98.4 ng/g (13.6–6217 ng/g), that
is, approximately one-half that of tris­(1,3-dichloro-2-propyl) phosphate,
a traditional high-production chloroalkyl OPTE. The detection frequencies
of DEGBBCEP and EBBCEP were 96% and 98%, respectively, but at relatively
low median concentrations of 10.6 ng/g (from not detected to 152 ng/g)
and 3.79 ng/g (from not detected to 130 ng/g), respectively. In standard
house dust SRM2585, DEGBBCEP and EBBCEP were detected at 160 ±
15.7 and 1897 ± 38.8 ng/g, respectively, but DEGBBCPP was not
detected. Future studies should evaluate the potential adverse health
effects of these emerging flame retardants.