Identification and characterization of quaternary ammonium compounds in Flemish indoor dust by ion-mobility high-resolution mass spectrometry

High-Resolution Mass Spectrometry Screening of Quaternary Ammonium Compounds (QACs) in Dust from Homes and Various Microenvironments in South China

“…Among the newly identified QACs, 16 were confirmed with commercially available standards (level S1), 11 matched reference MS/MS fragment ions (level S2), and 1 was tentatively identified through characteristic MS/MS fragmentations (level S3). Of these emerging QACs identified, only 13 have been reported in the environments, 9,13,23,24,30,42,48,49 demonstrating the effectiveness of the QAC screening strategy applied in the present study. The newly identified QACs were divided into three groups based on their structural similarity to traditional QACs, including 9 BAC analogues, 10 DADMAC analogues, and 9 ATMAC analogues (Figures 1 and S3−S5).…”

“…23 In addition, mixed DADMACs were constantly observed in dust along with paired DADMACs that had been frequently reported. 23 Two mixed DADMACs with long alkyl chains, C8:10-and C10:12-DADMAC, were detected in 100 and 94% of the samples with median concentrations of 0.244 and 0.0418 μg/g, respectively. The level of C8:10-DADMAC was also reported in dust collected from Europe (0.02 μg/g) 23 but 10 times lower than that determined in the current study.…”

“…23 Two mixed DADMACs with long alkyl chains, C8:10-and C10:12-DADMAC, were detected in 100 and 94% of the samples with median concentrations of 0.244 and 0.0418 μg/g, respectively. The level of C8:10-DADMAC was also reported in dust collected from Europe (0.02 μg/g) 23 but 10 times lower than that determined in the current study. Interestingly, mixed DADMACs with shorter alkyl chains, including C2:8-DADMAC, C2:12-DADMAC, C4:10-DADMAC, C6:8-DAD-MAC, and C2:14-DADMAC, were frequently detected in the current study (DF: 82−100%) and their median concentrations were 0.0717, 0.0908, 0.0253, 0.297, and 0.111 μg/g, respectively.…”

“…The total traditional QAC concentrations (∑ traditional QAC, sum of 18 traditional QACs) ranged from 13.8 to 150 μg/g at a median concentration of 42.2 μg/g, similar to those reported in residential dust collected from the United States (36.3−58.9 μg/g) 22 and almost 3 times higher than those reported in indoor dust from Europe (14.73 μg/g). 23 This can be attributed to the fact that several QACs, including C12-to C18-BACs and others, are currently under evaluation in the European Union before these chemicals can be approved to be active ingredients in the market. 23 Compared with other emerging contaminants previously reported in home dust from South China, the median concentration of ∑ traditional QAC measured in the current study was comparable to that for phthalate monoesters (45.4 μg/g), 36 higher than that for liquid-crystal monomers (18.5 μg/g) 50 and organophosphate esters (10.6 μg/g).…”

“…23 This can be attributed to the fact that several QACs, including C12-to C18-BACs and others, are currently under evaluation in the European Union before these chemicals can be approved to be active ingredients in the market. 23 Compared with other emerging contaminants previously reported in home dust from South China, the median concentration of ∑ traditional QAC measured in the current study was comparable to that for phthalate monoesters (45.4 μg/g), 36 higher than that for liquid-crystal monomers (18.5 μg/g) 50 and organophosphate esters (10.6 μg/g). 51 These results suggest that QACs are ubiquitous in indoor environments and may cause health risks to humans.…”