Collaborative Study of Three Methods for the Determination of Fluoride in Vegetation

1978 ◽  
Vol 61 (1) ◽  
pp. 150-153
Author(s):  
Jay S Jacobson ◽  
Laurence I Heller

Abstract A procedure is described for determining Kepone (decachlorooctahydro-l,3,4-metheno-2ffcyclobuta[ cd]pentalene-2-one) residues in avian egg, liver, and tissue. Samples were extracted with benzene-isopropanol, and the extract was cleaned up with fuming H2S04-concentrated H2SO4. Kepone was separated from organochlorine pesticides and polychlorinated biphenyls on a Florisil column and analyzed by electron capture gas-liquid chromatography (GLC). The average recovery from spiked tissues was 86%. The analyses performed on 14 bald eagle carcasses and livers, 3 bald eagle eggs, and 14 osprey eggs show measurable levels which indicate that Kepone accumulates in the tissues of fish-eating birds. Residues were confirmed by GLC-mass spectrometry

1978 ◽  
Vol 61 (1) ◽  
pp. 08-14 ◽  
Author(s):  
Charles J Stafford ◽  
William L Reichel ◽  
Douglas M Swineford ◽  
Richard M Prouty ◽  
Martha L Gay

Abstract A procedure is described for determining Kepone (decachlorooctahydro-l,3,4-metheno-2H-cyclobuta [cd]pentalene-2-one) residues in avian egg, liver, and tissue. Samples were extracted with benzene-isopropanol, and the extract was cleaned up with fuming H2SO4-concentrated H2SO4. Kepone was separated from organochlorine pesticides and polychlorinated biphenyls on a Florisil column and analyzed by electron capture gas-liquid chromatography GLC). The average recovery from spiked tissues was 86%. The analyses performed on 14 bald eagle carcasses and livers, 3 bald eagle eggs, and 14 osprey eggs show measurable levels which indicate that Kepone accumulates in the tissues of fish-eating birds. Residues were confirmed by GLC-mass spectrometry.


1976 ◽  
Vol 59 (1) ◽  
pp. 209-212
Author(s):  
Lawrence R Mitchell

Abstract A method for the determination of endosulfan I, endosulfan II, endosulfan sulfate, tetrasul, and tetradifon residues in fresh fruits and vegetables was studied collaboratively. The method consists of extraction of the product with acetonitrile, extract cleanup by partition with petroleum ether and elution from a Florisil column with mixtures of hexane, methylene chloride, and acetonitrile, and determination of the residues by electron capture gas-liquid chromatography. This method was studied by 8 collaborators, using apples and cucumbers as the samples. Each sample was spiked with 2 levels of each pesticide. The average per cent recoveries for apples and cucumbers, respectively, were as follows: endosulfan I, 103.6 and 101.5; endosulfan II, 102.9 and 100.0; endosulfan sulfate, 100.9 and 92.9; tetrasul, 98.8 and 102.2; and tetradifon, 106.4 and 101.9. The method has been adopted as official first action.


1974 ◽  
Vol 57 (3) ◽  
pp. 518-521
Author(s):  
Charles E Finsterwalder

Abstract Eleven laboratories collaboratively studied a method for the determination of polychlorinated biphenyls (PCBs) (Aroclors 1242 and 1254) in paperboard, which involves alcoholic potassium hydroxide extraction, Florisil column cleanup, and electron capture gas-liquid chromatography. Blank paperboard spiked with 2 levels of each Aroclor and paperboard which had Aroclor 1242 incorporated during manufacture were analyzed. Average recovery of Aroclor 1242 at the 12.5 ppm level was 80.8%; at the 8.2 ppm level, 87.8%. Average recovery of Aroclor 1254 at the 12.3 ppm level was 87.0% ; at the 8.9 ppm level, 85.4%. The mean recovery of Aroclor 1242 from the specially prepared paperboard was 5.6 ppm, with a standard deviation of 15.8%. The method has been adopted as official first action.


1971 ◽  
Vol 54 (2) ◽  
pp. 361-363
Author(s):  
D E LaCroix ◽  
N P Wong

Abstract A rapid method is described for the extraction and quantitative determination of sorbic acid in Cheddar cheese. Cheddar cheese is impregnated onto a Celite 545 column, extracted with acetonitrile, and analyzed for sorbic acid by gas-liquid chromatography, using a 7.5% ethylene glycol adipate + 2% H3PO4 column. Average recovery values for known amounts of sorbic acid were 107%.


1980 ◽  
Vol 63 (1) ◽  
pp. 49-55
Author(s):  
Iwao Okuno ◽  
Dennis L Meeker

Abstract An analytical method is described for the determination of Compound 1080 (sodium fluoroacetate) residues in 1–10 g tissue. Sample extracts of tissues are cleaned up with silica gel, and Compound 1080 (as fluoroacetic acid) is separated by a micro-distillation procedure. The fluoroacetic acid in the distillate is derivatized with pentafluorobenzyl bromide to form pentafluorobenzyl fluoroacetate which is measured by electron capture gas-liquid chromatography. Recoveries of sodium fluoroacetate from fortified tissue samples averaged about 25%. Despite the limited recoveries, results were quite reproducible, and levels as low at 2 ppm were determined in fortified 1 g samples, and 0.2 ppm in 10 g samples. The method is relatively simple and has been used routinely in our laboratory for the analysis of various types of samples such as grain, and tissues from birds, rodents, and larger animals.


1974 ◽  
Vol 57 (2) ◽  
pp. 341-342
Author(s):  
Caesar B Garavelli

Abstract A procedure is described for the quantitative determination of 0.020—6.0 mg choline in low and high potency reference multiple vitamin tablets and standard liver preparations. The trimethylamine quantitatively produced in a sealed tube by treatment with aqueous 5 0% alkali is simultaneously extracted with 0.200—0.500 ml of an isobutanol-ethanol (1+1) mixture and determined by gas-liquid chromatography. An average recovery of 100 ± 3 % was obtained.


1976 ◽  
Vol 22 (6) ◽  
pp. 915-921 ◽  
Author(s):  
G F Johnson ◽  
C J Least ◽  
J W Serum ◽  
E B Solow ◽  
H M Solomon

Abstract We describe a case of fatal overdosage with primidone and methsuximide. During the early phase of the patient's hospital course we found concentrations of methsuximide, N-desmethylmethsuximide, and primidone in serum that far exceeded the usual therapeutic concentrations, as determined by gas-liquid chromatography. Determination of N-desmethylmethsuximide in peritoneal fluid demonstrated concentrations comparable to those in serum. This led to the therapeutic decision to manage the patient by dialysis. Subsequently, serum samples collected during the course of hospitalization were analyzed quantitatively by gas-liquid chromatography for methsuximide, N-desmethylmethsuximide, primidone, phenobarbital, and diphenylhydantoin. Selected serum specimens were also analyzed by gas chromatography-mass spectrometry, and N-methyl-2-hydroxymethyl-2-phenylsuccinimide, a metabolite of methsuximide not previously described in human serum, was identified by analysis of its mass spectrum.


1970 ◽  
Vol 53 (1) ◽  
pp. 149-151
Author(s):  
Robert C Randall

Abstract Six collaborators studied a spectrophotometric method in which the chopped product is extracted with CHCl3, the extract is cleaned up on a Florisil column, and the residue is determined spectrophotometrically in the UV region (283 nm). The overall average recovery of the collaborative study was 93%. It is recommended that the method be adopted as official first action.


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