| dc.description.abstract | Mirex was a highly chlorinated flame retardant. During the mid-1960s, it was used as a pesticide and also as a flame retardant in plastics, rubber, paint, and electrical goods. The nonagricultural uses of this chemical were banned in the 1970s because of its toxicity, and then partially replaced by other highly chlorinated compounds, such as Dechlorane 602, Dechlorane 603, Dechlorane 604 and, in particular, Dechlorane Plus, which have flame-retardant properties similar to that of mirex.
A simple and solvent-minimized procedure for the determination of five chlorinated flame retardant in aqueous samples using ultrasound-assisted dispersive liquid-iquid microextraction (UA-DLLME) coupled with gas chromatography–electron-capture negative ion mass spectrometry (GC-ECNI-MS) is presented. The parameters affecting the extraction efficiency of analytes from water samples were systematically investigated. The best extraction conditions involved the rapid injection of a mixture of 1.0 mL of acetonitrile (as a dispersant) and 60 μL of carbon tetrachloride (as an extractant) into 10 mL of water containing 0.5 g of sodium chloride in a conical bottom glass tube. After ultrasonication for 1.0 min and centrifugation for 10 min at 6,000 rpm(ca. 3940 g). The sedimented phase was evaporated to dryness and re-dissolved in 50 μL of acetone containing internal standard for further GC-ECNI-MS analysis. The limits of detection were 0.05-0.5 ng/L. The precision for these analytes, as indicated by relative standard deviations (RSDs), was less than 10% for both intra- and inter-day analysis. Their total concentrations were determined in the range from 0.15 to 0.33 ng/L in various water samples.
Overall, UA-DLLME appears to be a good alternative extraction method for the determination of chlorinated flame retardants in environmental water samples, in that it is a simple, low cost, rapid, and eco-friendly analytical method. | en_US |