Determination of 2,6-di-tert-butyl-hydroxytoluene and its transformation products in indoor dust and sediment by gas chromatography-mass spectrometry coupled with precolumn derivatization.

We developed an analytical method to simultaneously determine 2,6-di-tert-butyl-hydroxytoluene (BHT) and its four transformation products in indoor dust and sediment samples. BHT, 2,6-di-tert-butylcyclohexa-2,5-diene-1,4-dione (BHT-Q), and 3,5-di-tert-butyl-4-hydroxybenzaldehyde (BHT-CHO) were measured by gas chromatography-mass spectrometry (GC-MS) after ultrasonic extraction with hexane/dichloromethane (1:3), while 2,6-di-tert-butyl-4-(hydroxymethyl) phenol (BHT-OH) and 3,5-di-tert-butyl-4-hydroxybenzoic acid (BHT-COOH) were derivatized using N, O-bis (trimethylsilyl) trifluoroacetamide before GC-MS analysis. The limits of detection (LODs) and quantification (LOQs) of the developed method were 0.02-0.34 and 0.08-1.14ngg-1 . The recoveries for BHT and its transformation products were 71.1-118% with relative standard deviations <10.6% at different spiking levels. The method was applied to indoor dust and sediment samples, showing that BHT was found in all samples with concentrations being 0.22-47.37μgg-1 in dust and 0.09-6.93μgg-1 in sediment. BHT-Q was the dominant transformation product, followed by BHT-CHO, BHT-OH, and BHT-COOH. Different metabolite profiles for BHT indicated various transformation pathways, making it necessary to study their transformation mechanism and environmental behaviors in the future studies.