Surrogate-assisted determination of 2,3,7,8-tetrachlorodibenzo-p-dioxin in fish by electron capture capillary gas chromatography.
Surrogate spiking the sample with 1000 parts per trillion (pptr) 1,3,7,8-tetrachlorodibenzo-p-dioxin (1378-TCDD) has doubled analytical throughput in determining toxic 2378-TCDD (analyte) at the low part-per-trillion level in fish, using multicolumn high resolution liquid chromatographic cleanup before quantitation by capillary gas chromatography with electron capture detection. The 1378- and 2378-TCDD were recovered equally and were well separated by the capillary column so that the earlier-eluting surrogate did not interfere with the quantitation of levels of analyte many-fold lower. Matrix interference contributed less than 1% bias in surrogate quantitation. Using surrogate recovery to correct for analyte losses during analysis, accuracy averaged (n = 7) 105% in determining 18 or 45 pptr 2378-TCDD added to fish without detectable bioincurred analyte. Analyses of selected fish with bioincurred 2378-TCDD gave results comparable to earlier work where recovery correction required a second analysis of sample fortified with analyte. With surrogate fortification, repeatability of determination (n = 3 or 4) improved markedly to less than 5% relative standard deviation at 37-46 pptr.
D000818:Animals; D055598:Chemical Phenomena; D002621:Chemistry; D002849:Chromatography, Gas; D004147:Dioxins / Q000032:analysis*; D005399:Fishes / Q000378:metabolism*; D008401:Gas Chromatography-Mass Spectrometry; D000072317:Polychlorinated Dibenzodioxins / Q000032:analysis*; D014873:Water Pollutants / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
D004147:Dioxins; D000072317:Polychlorinated Dibenzodioxins; D014873:Water Pollutants; D014874:Water Pollutants, Chemical