Improved extraction procedures for polychlorinated biphenyls in solid samples with aqueous sodium hydroxide under autoclave conditions.
The efficacy of the extraction of polychlorinated biphenyls (PCBs) from varnish-infiltrated insulating papers as a model of solid materials with an aqueous sodium hydroxide (NaOH) by autoclaving at 121 degrees C for 30 min was compared with those for the conventional procedures, i.e., saponification with 1 N ethanolic NaOH in a boiling water bath for 60 min and extraction with benzene in a Soxhlet apparatus. The newly invented autoclaving method was found to be superior to the conventional ones, yielding approximately 5- to 6-fold cumulative PCB congeners without being accompanied by extended decomposition. Therefore, the autoclave-based sample treatment is recommended for more accurate determination of PCBs in the case of PCB-impregnated solid materials such as hardened oils and resin-coated or -infiltrated papers instead of being treated conventionally.
Akimoto
Y
Y
School of Pharmaceutical Sciences, Toho University, Chiba, Japan. yoshito.masuda@nifty.ne.jp
Inouye
Y
Y
D002623:Chemistry Techniques, Analytical / Q000379:methods*; D004785:Environmental Pollutants / Q000032:analysis; D011078:Polychlorinated Biphenyls / Q000032:analysis* / Q000737:chemistry; D012972:Sodium Hydroxide / Q000737:chemistry
D004785:Environmental Pollutants; D012972:Sodium Hydroxide; D011078:Polychlorinated Biphenyls