Chemical analysis of human blood for assessment of environmental exposure to semivolatile organochlorine chemical contaminants.

A chemical method for the quantitative analysis of organochlorine pesticide residues present in human blood was scaled-up to provide increased sensitivity and extended to include organochlorine industrial chemicals. Whole blood samples were extracted with hexane, concentrated, and analyzed without further cleanup by gas chromatography with electron capture detection. The methodology used was validated by conducting recovery studies at 1 and 10 ng/g (ppb) levels. Screening and confirmational analyses were performed by gas chromatography/mass spectrometry on samples collected from potentially exposed residents of the Love Canal area of Niagara Falls, New York and from volunteers in the Research Triangle Park area of North Carolina for 25 specific semivolatile organochlorine contaminants including chlorobenzene and chlorotoluene congeners, hexachloro-1,3-butadiene, pesticides, and polychlorinated biphenyls as Aroclor 1260. Dichlorobenzene, hexachlorobenzene, and beta-hexachlorocyclohexane residues fell in the range of 0.1 to 26 ppb in a high percentage of both the field and volunteer blood samples analyzed. Levels of other organochlorine compounds were either non-detectable or present in sub-ppb ranges.

Simplified micro perchlorination method for polychlorinated biphenyls in biological samples.

Simplified methodology is presented for the micro determination of polychlorinated biphenyls (PCBs) in biological samples, by conversion to the decachlorobiphenyl (DCB) derivative. Beef adipose tissue and human milk extracts were fortified with PCB standards at 0.1--5.0 ppm, and perchlorinated with antimony pentachloride (SbCl5). Several Aroclors representing various degrees of chlorine content were investigated to assess the efficiency of conversion to DCB. Samples were cleaned up on a Florisil mini column and the PCBs were quantitated by electron capture GLC. Several chlorinated pesticides which were subjected to the perchlorination procedure did not interfere. As little as 0.1 ppm PCBs in 500 mg tissue extract can be recovered at 79-99%. The background DCB content of several brands of SbCl5 was determined. The levels of PCBs in human milk obtained by the perchlorination technique are compared with data acquired by electron capture gas-liquid chromatography in which the individual chlorobiphenyls in the sample are measured.

Improved recovery of hexachlorobenzene in adipose tissue with a modified micro multiresidue procedure.

Using the described methodology the recovery of hexachlorobenzene from adipose tissue was significantly increased over that normally obtained with other multiresidue procedures. The recovery of other commonly encountered chlorinated hydrocarbon pesticides was not affected nor was the "background" from adipose tissue intolerable. Although extensive work has not been done, it is likely that improved recovery of hexachlorobenzene could be expected from other tissues.

Rapid determination and confirmation of low levels of hexachlorobenzene in adipose tissues.

The described procedure can be utilized for rapid, simple quantitation and confirmation of hexachlorobenzene in fatty tissue at levels as low as 5 ppb without the use of sophisticated and expensive equipment. Interferences can be circumvented in many instances without additional separation by selection and preparation of the appropriate derivative.

Improved method for hexachlorobenzene and mirex determination with hexachlorobenzene confirmation in adipose tissue: collaborative study.

A previously published method for determination and confirmation of hexachlorobenzene (HCB) in adipose tissue was also applied to mirex residues. A modified procedure for both residues was collaboratively studied by 12 laboratoires. The procedure specifies direct application of an extracted or rendered fat sample to a Florisil cleanup column and one-fraction elution. Mirex and HCB are determined by direct GLC of the concentrated eluate. HCB residues are then confirmed by reaction with isopropanol to form the disubstituted bis-isopropoxytetrachlorobenzene (BITB) derivative. Mirex residues are destroyed by this reaction. All participants were asked to analyze an unknown standard mixture of HCB and mirex and 10 rendered chicken fat samples consisting of one blank and 9 samples fortified samples represented 3 samples at each of 3 fortification levels. The HCB fortifications of 20.0, 33.3, and 50.0 ppb yielded average interlaboratory recoveries of 89.6, 87.4, and 92.6%, respectively. The respective coefficients of variation (CV) for HCB results were 9.1, 6,8, and 10.0%. The mirex fortifications of 150, 300, and 500 ppb yielded average interlaboratory recoveries of 89.0, 90.2, and 92.3%, respectively. The respective CV values for mirex results were 7.6, 16.5, and 18.1%. The method has been adopted official first action.

Electron capture gas chromatographic determination of Kepone residues in environmental samples.

The pollution of the environment with Kepone (decachlorooctahydro-1,3,4-metheno-2H-cyclobuta[cd]pentalen-2-one) by an industrial manufacturer of the pesticide resulted in the contamination of several terrestrial media, including biological life, near the entry of the insecticide into the ecosystem. The substrata investigated and for which residue methodology was developed included river sediment, soil, water, shellfish, and finfish. Rigorous extraction techniques utilizing the Soxhlet apparatus and the Polytron tissue homogenizer were required for complete removal of Kepone from the samples. Finfish tissue was the most difficult to analyze. For this type of substratum, a preliminary cleanup by gel permeation chromatography was required to remove most of the lipid material followed by a micro Florisil column elution to eliminate polychlorinated biphenyls (PCB'S). Cleanup of shellfish and other environmental samples was accomplished with a micro Florisil column only. Electron capture gas chromatography was used to analyze the sample extracts. Recoveries of Kepone from fortified samples averaged 84% or greater.