bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gas Chromatographic Determination of Trifluralin, Diallate, Triallate, Atrazine, Barban, Diclofop-Methyl, and Benzoylprop-Ethyl in Sediments at Parts Per Billion Levels
Authors: Lee Hing-Biu , Chau Alfred S Y 
Published: February 2020

Abstract
A sensitive gas chromatographic method was developed for the multiresidue determination of 7 neutral herbicides in sediment. The sediment sample was ultrasonically extracted 3 times with acetone. The extract was concentrated to about 50 mL and then partitioned with 2% KHCO3 and CH2C12. The organic phase was dried over anhydrous Na2So4. The concentrated extract was then cleaned up on a 10% deactivated Florisil column, and the herbicides were separated into 2 fractions. Further cleanup of these fractions was performed on activated Florisil columns. Electron capture detection was used for analysis except for atrazine which was analyzed by nitrogen-phosphorus detection. Recoveries of the herbicides from fortified sediment samples at 3 levels were generally better than 80%. The practical detection limit of this method was 1 ppb or 1 ng/g based on a 50 g sediment sample.
Evaluation of Nielsen-Kryger Steam Distillation Technique for Recovery of Phenols from Soil
Authors: Narang Amarjit S , Vernoy Charles A , Eadon George A 
Published: February 2020

Abstract
The Nielsen-Kryger steam distillation technique has been evaluated for recovery of phenols from soil. Soils are acidified to pH &lt;1 and steam-distilled, and chlorinated phenols are extracted with toluene-methylene chloride (95 + 5). Mean recoveries from 4 samples spiked at 1 μg/50 g clay soil ranged from 67 to 78%. The method has limited utility for the recovery of other substituted phenols on the Environmental Protection Agency priority pollutant list.
Semiautomated Fluorometric Method for Determination of Vitamin C in Foods: Collaborative Study
Authors: DeVries Jonathan W ,   Collaborators:, Defibaugh P W , Dunmire D , Ebert F , Ge H , Oman G , Lim N , Moffitt R A , Muelle E E , Schnitzer R , Shaffer S 
Published: February 2020

Abstract
Continuous flow automation of the microfluorometric procedure compares favorably with the manual method in sensitivity, specificity, and generality, and reduces the cost of routine vitamin C assay. Fifteen samples of 12 different products of ready-to-eat cereals, fruit juices, and infant formula were sent to 6 collaborators; one sample in each category was sent as blind duplicates. The within-laboratory standard deviations for 5 collaborators on the 3 sets of blind duplicates were 1.23, 0.87, and 3.64 mg/100 g, respectively. Overall, the average relative standard deviation between laboratories was 11.1% (range 4.5-16.6%) for the manual method and 4.99% (range 1.5-12.6%) for the semiautomated method. The method has been adopted official first action.
Titratable Acidity in Corn Syrup: Collaborative Study
Authors: Bernetti Raffaele , Owen Roger ,   Collaborators:, Harness J , Holme R A , Hovden R , Owen R L , Schopmeyer H H , Steele E M , Wolff P 
Published: February 2020

Abstract
Six sets of blind duplicate samples of commercial corn syrups, including high fructose corn syrups, were distributed to 9 collaborating laboratories. Samples were titrated with alkali, according to the AOAC method, to a phenolphthalein "faint pink" end point as well as being assayed by a modified method specifying a larger sample, more dilute alkali, and electrometric end points at pH 6.0,7.0, and 8.3. Repeatabilities and reproducibilities were about as poor in the AOAC method as in the modified method at pH 8.3, but improved considerably when the modified electrometric end point method was carried out to pH 6.0. The method calling for electrometric titratable acidity at pH 6.0 end point was adopted official first action, and the present method, 31.217, was deleted.
Direct Determination of Lead in Evaporated Milk and Apple Juice by Anodic Stripping Voltammetry: Collaborative Study
Authors: Zink Eric W , Davis Phillip H , Griffin Reginald M , Matson Wayne R , Moffitt Robert A , Sakai David T ,   Collaborators:, Abbe S , Booth H , Brumley J , Chamberlain N , Chisolm J J , Green R , Harrison H , Hudak J W , Neuman T R , Phillips R N , Rieders F , Shelhorse N A , Sideman L , Spratt E , Sulek A M , Walkowiak W 
Published: February 2020

Abstract
A method for the direct determination of lead in evaporated milk and in fruit juice with no prior sample digestion was successfully collaborated by 13 laboratories. The anodic stripping voltammetric (ASV) method studied consisted of adding 0.2 mL aliquots of evaporated milk or 0.3 mL aliquots of fruit juice to 2.9 mL of a dechelating reagent, Metexchange. The reagent-sample mixture is then analyzed for lead by ASV with no further sample preparation. Each collaborator received 24 samples, 2 each at 5 different levels (0.07-0.70 ppm for spiked evaporated milk and 0.09-0.87 ppm for spiked apple juice) along with duplicate practice samples of labeled lead content at each of 2 levels for each sample type. All unknowns were coded with random numbers. Approximately 69% of the reporting laboratories had never analyzed either evaporated milk or fruit juice for lead. Average time between receipt of samples and reporting of results was 1.6 days for all laboratories. The pooled variations between duplicate determinations for apple juice and evaporated milk were 0.00059 and 0.00043, respectively. The method was adopted official first action for both fruit juice and evaporated milk.
Separation and Characterization of Amine Drugs and Their Enantiomers by Capillary Column Gas Chromatography-Mass Spectrometry
Authors: Liu Ray H , Ku Warren W , Fitzgerald Mary P 
Published: February 2020

Abstract
A gas chromatograph-mass spectrometer-data system equipped with a capillary column is used to analyze commonly abused amine drug mixtures. Enantiomeric amines are analyzed as N-trifluoroacetyl- I-prolyl chloride derivatives. The 10 compounds included in this study are amphetamine, methamphetamine, norephedrine, ephedrine, 3,-4-methylenedioxyamphetamine, N,N-dimethyltryptamine, N,N-diethyltryptamine, N,N-dimethyl-5-methoxytryptamine, mescaline, and caffeine. All compounds, including possible enantiomers, are resolved and identified by the described method.
Analysis for Fusarium Toxins in Various Samples Implicated in Biological Warfare in Southeast Asia
Authors: Mirocha Chester J , Pawlosky Robert A , Chatterjee Kajal , Watson Sharon , Hayes Wallace 
Published: February 2020

Abstract
Samples of leaves, water, cereal grains, soil, and yellow powder as well as blood, urine, and body tissues from chemical warfare victims were analyzed for Fusarium toxins by using gas chromatography and mass spectrometry. The leaves, water, and yellow powder samples contained various combinations of T-2 toxin, diacetoxyscirpenol, deoxynivalenol, nivalenol, and zearalenone in concentrations ranging from trace (1.0 ppb) amounts to 143 ppm. These trichothecenes do not occur naturally on the substrates described and were correlated with the so-called "yellow rain" chemical attacks against Hmong people in Southeast Asia. Analysis of leaves, soil, water, and cereals collected in areas adjacent to but apart from the area where chemical attacks had been staged did not contain any Fusarium toxins. Moreover, T-2 and HT-2 toxins were found in human blood, urine, and body tissues (heart, esophagus, kidney, lung, and large intestine) of alleged victims. In addition, diacetoxyscirpenol was found in the kidney of one person who had died
Potentiometric Determination of Chlorine in Microliter Water Samples
Authors: Paterson A H J , Kerekes R J 
Published: February 2020

Abstract
A novel method has been developed to measure low concentrations (about 100 ppm) of chlorine in very small (1–5 μL) samples of water. The method uses a specially cast silicone rubber cap fitted over the tip of a combination electrode probe. The fabrication, calibration, and use of this modified commercial probe is described in detail.
Histologic Detection of Cardiac Musculature, Soy Flour, and Partially Defatted Tissue in Ground Beef: Interlaboratory Study
Authors: Carey Albert M , Archer Jean N , Priore Joseph D , Kotula Anthony W ,   Collaborators:, Cannon L D , Carey A M , Deshmukh D R , Dyer J E , Glenn M W , Langheinrich K A 
Published: February 2020

Abstract
A collaborative study was designed and conducted to evaluate the accuracy of a procedure for the histologic detection of cardiac muscle, soy flour, and partially defatted tissue that may occur as adulterants in ground beef. Ground beef samples were prepared containing 0, 3, 5, 10, and 15% of each of the 3 adulterants. Five samples of each composition at each of the 5 dilutions, for a total of 75 unknown samples, were analyzed at each of 5 participating laboratories. The study revealed that this technique is reliable for the detection of these adulterants in ground beef.
Pesticide, Heavy Metal, and Other Chemical Residues in Infant and Toddler Total Diet Samples. (IV). October 1977–September 1978
Authors: Podrebarac David S 
Published: February 2020

Abstract
The Food and Drug Administration has conducted the Total Diet Study since 1964. The program originally focused on the average total diet of the young adult male but was eventually expanded to include the average total diets of infants and toddlers. This report is the fourth in the infant and toddler series and represents residues found in market basket samples, i.e., items comprising the average 2-week diet of infants and toddlers, collected in 10 different cities throughout 4 geographic areas of the United States from October 1977 through September 1978. The results are based on analyses of food composites representing 11 food classes into which all the food items were separated. Averages and ranges are reported for residues of pesticides, herbicides, fungicides, and selected metals and industrial chemicals. Recovery results are also included for various representative compounds added to a variety of food classes. The results for the adult market basket samples for the same reporting period are presented in a separate report.
Pesticide, Metal, and Other Chemical Residues in Adult Total Diet Samples. (XIV). October 1977–September 1978
Authors: Podrebarac David S 
Published: February 2020

Abstract
Residues of pesticides, herbicides, fungicides, and selected industrial chemicals and metals have been reported since 1964 through the Total Diet Study conducted by the Food and Drug Administration. This report, which is the fourteenth in the series, includes data for the adult diet market basket samples collected from October 1977 through September 1978 in 20 cities throughout 4 geographical areas. All items from each market basket were separated into 12 food classes for analysis, and the averages and ranges of the residues found are presented in various formats. In addition to the 240 composites analyzed, the individual items making up the dairy composites and the meat-fishpoultry composites were analyzed separately for 4 market baskets. The results of a recovery study in which composites were fortified with the more commonly reported residue compounds are also presented as a part of this report. Results for the infant and toddler Total Diet market baskets for the same period are published in a separate report.
Mass Spectrometric Determination of Cane Sugar and Corn Syrup in Maple Syrup by Use of 13C/12C Ratio: Collaborative Study
Authors: Morselli Maria Franca , Baggett Kelly L ,   Collaborators:, Bender M , Cairo O , Fontes J C , Fritz P , Gagnon M , Gearing P , Hillaire-Marcel C , Knyf M , Krouse H R , Schwarcz H P 
Published: February 2020

Abstract
Use of C3 carbon dioxide (CO2) fixation cycle by the sugar maple (Acer saccharum Marsh.), a dicotyledenous plant, and C4 carbon fixation cycle by 2 monocotyledenous plants, corn and cane, results in a physiological discrimination between 13C and 12C isotopes. Therefore, determination of 13C/12C ratio of maple syrup by mass spectrometry can be used to detect adulteration with cane and corn sugars. Four samples of pure maple syrup and 3 adulterated maple syrup samples were analyzed in a collaborative study. Results indicate that stable carbon isotope analysis can determine authenticity of maple products. Samples with δ13C values less negative than – 23.49%c (parts per thousand) can, with a high degree of confidence (95%), be classified as adulterated. The method has been adopted official first action.
Effects of Methanol Concentration and Solvent:Peanut Ratio on Extraction of Aflatoxin from Raw Peanuts
Authors: Whitaker Thomas B , Whitaker Thomas B , Dickens James W , Giesbrecht F G 
Published: February 2020

Abstract
Aflatoxin Bi was extracted by a water slurry process using methanol concentrations of 55, 60, 65, and 70% in water and solvent:peanut ratios of 3, 4, 5, and 6 mL/g. Results failed to show that methanol concentration had an effect on amount of B1 extracted; however, the amount of B1 extracted increased with an increase in solvent:peanut ratio. Aflatoxin Bt was also extracted by the official AOAC method II, using methanol concentrations of 55, 60, 65, and 70% in water and solvent:peanut ratios of 2, 3, 4, and 5 mL/g. Results showed that the amount of B1 extracted increased with percent methanol at low solvent: peanut ratios but not at high ratios. Also, the amount of B1 extracted increased with solvent:peanut ratios at all methanol concentrations.
Fluorometric Screening Method for Citrinin in Corn, Barley, and Peanuts
Authors: Trantham Allen L , Wilson David M 
Published: February 2020

Abstract
A fluorometric method is described for rapid screening of citrinin in corn, barley, and peanuts. The initial extraction uses an aqueous acidified acetonitrile solution, and the resulting extract is partially purified by several acid–base partition steps. Citrinin is determined by using a fluorometer. Mean recoveries of added citrinin from corn, barley, and peanuts were 56.4,66.6, and 40.0 %, respectively, at levels of 100–8000 ng/g.
Simple Colorimetric Estimation of Cyclopiazonic Acid in Contaminated Food and Feeds
Authors: Rathinavelu A , Shanmugasundaram Edayathimangalam Rajabhavani B 
Published: February 2020

Abstract
A method has been developed for quantitative determination of cyclopiazonic acid, a mycotoxin produced by a common food contaminant, Penicillium cyclopium. The organism was grown successively in synthetic minimal medium, rice, corn, and wheat for 15 days. The toxin was extracted with chloroform followed by separation by thin layer chromatography. A colorimetric assay procedure has been successfully developed for the analysis of cyclopiazonic acid present in infected rice, corn, and wheat. The sensitivity of the method was tested by using recovery experiments.
Deoxynivalenol in Winter Wheat: Thin Layer Chromatographic Method and Survey
Authors: Eppley Robert M , Trucksess Stanley Nesheim Mary W , Thorpe Charles W , Wood Garnett E , Pohland Albert E 
Published: February 2020

Abstract
A rapid method for the determination of deoxynivalenol (DON) in wheat was used to analyze 57 wheat samples collected from 4 midwestern states where the winter wheat crop was contaminated with Fusaria. The method involves sample extraction with acetonitrilewater (84 + 16), cleanup by charcoal-alumina column chromatography, and determination by thin layer chromatography (TLC), using an AlClj solution spray and heat to form a fluorescent derivative. Recoveries of DON added to wheat at levels as low as 0.2 μg/g averaged &gt;80%. DON was detected at an average level of 3.6 μg/g; the levels ranged from 0.2 to 9.0 μg/g in 54 of 57 of the wheat samples. The quantity of DON was, in general, proportional to the percentage of total damaged kernels (grade). The chemical identity of DON was confirmed by mass spectrometry after isolation with preparative TLC.
Enzyme-Linked Immunosorbent Assay of Ochratoxin A in Wheat
Authors: Lee Sungsoo C , Chu Fun S 
Published: February 2020

Abstract
An enzyme-linked immunosorbent assay (ELISA) was developed for the quantitation of ochratoxin A amended to wheat. Ochratoxin A conjugated to horseradish peroxidase (HRP) was used as an enzyme marker in the assay. At toxin levels below 30 ppb, a cleanup treatment was necessary for ELISA. Among 3 cleanup methods tested (solvent partition, Sep-Pak cartridge treatment, solvent partition and cartridge treatment), reverse phase cartridge treatment was the most simple and effective. In the analysis, ochratoxin A was extracted from wheat with methanol. The methanolic extract was diluted with water to a final 10–15% methanol content, and then passed through a cartridge. Ochratoxin A was eluted from the cartridge with 85% methanol which was then concentrated. The final solution, in 0.1M, pH 7.5 sodium phosphate–Tween 20 buffer and 5% methanol, was then subjected to ELISA. ELISA allowed minimal detection of the toxin in wheat at the 1–2 ppb level after cleanup. Recoveries of toxin added to wheat samples in the 1.0–30 ppb range were 85–90% with standard deviations of 10–15%.
Rapid Determination of Deoxynivalenol (Vomitoxin) by Liquid Chromatography Using Modified Romer Column Cleanup
Authors: Chang Henry L , Devries Jonathan W , Larson Paul A , Patel Hasmukh H 
Published: February 2020

Abstract
A modification of the Romer method for determining deoxynivalenol (DON) provides rapid sample cleanup and includes liquid chromatographic (LC) quantitation. The method was evaluated using wheat, wheat flour, and other wheat products. The sample is extracted with acetonitrile–water (84 + 16), and an aliquot of the extract is subjected to activated charcoal–alumina column chromatography. The extract is then evaporated and diluted to volume with mobile phase, and DON is quantitated using liquid chromatography. The relative standard deviation based on duplicate samples is 6.07%. The detection limit is 30 ppb based on 2 x signal/noise ratio. Results by this method compared with the results obtained by the Scott GC method showed a correlation coefficient of 0.992 with a mean vomitoxin content of 779 ppb by this method and 716 ppb by the Scott method for 14 samples.
Determination of N-Nitrosodimethylamine in Nonfat Dry Milk: Collaborative Study
Authors: Sen Nrisinha P , Seaman Stephen , Karpinsky K ,   Collaborators:, Castegnaro M , Ellen G , Fiddler W , Lamontagne J C , Houlahan B J , Issenberg P , Klein D , Scanlan R , Thomas G , Thomsen J 
Published: February 2020

Abstract
Ten laboratories participated in a collaborative study of a method for the determination of JV-nitrosodimethylamine (NDMA) in nonfat dry milk. NDMA is eluted with dichloromethane from a mixture of Celite, acidic sulfamic acid, and nonfat dry milk (all packed in a chromatography column), concentrated in a Kuderna-Danish concentrator, and finally analyzed by a GC-thermal energy analyzer technique. Ten samples were studied: 6 were naturally contaminated (NDMA levels 0.38- 3.56 ppb) and 4 were spiked with known levels (0.96 and 3.2 ppb) of NDMA. The coefficients of variation (CV) of the complete data for the naturally contaminated samples (excluding the 2 samples containing the lowest levels) were 8.5% and 22.5% for repeatability and reproducibility, respectively. The corresponding CVs for the spiked samples were 14.4% and 20.4%, respectively. The percent recoveries of the added NDMA in the spiked samples (at the 2 levels indicated above) were 101.6 ± 3.2 (omitting 1 outlier) and 95 ∓ 2.1, respectively. The method has been adopted official first action.
Liquid Chromatographic Determination of Intermediates, Subsidiary Colors, and Two Reaction By-Products in FD&C Yellow No. 6: Reverse Phase Method
Authors: Cox Elizabeth A , Richfield-Fratz Naomi , Bailey Catherine J , Albert Richard H 
Published: February 2020

Abstract
A reverse phase liquid chromatographic (LC) method is presented for determining intermediates, subsidiary colors, and 2 reaction by-products in FD&C Yellow No. 6. Gradient elution from 0.02M ammonium acetate to 60% methanol in 0.02M ammonium acetate is performed on a C-8 column. Recoveries of the analytes from samples of FD&C Yellow No. 6 were as follows: 82 to 129% for the intermediate sulfanilic acid added at levels ranging from 0.04 to 0.2%; 85 to 107% for the intermediate Schaeffer's salt added at levels ranging from 0.03 to 0.3%; 91 to 107% for the reaction by-product 4,4'-(diazoamino)-dibenzenesulfonic acid added at levels ranging from 0.01 to 0.1%; 67 to 108% for the reaction by-product 6,6'-oxybis(2-naphthalenesulfonic acid) added at levels ranging from 0.1 to 1%; 88 to 100% for the subsidiary color 3-hydroxy-4-[(4-sulfophenyl)azo]-2,7-naphthaIenedisulfonic acid added at levels ranging from 0.7 to 5%; and 43 to 106% for the subsidiary color 6-hydroxy-5-(phenyIazo)-2-naphthalenesulfonic acid added at levels ranging from 0.1 to 1 %. To further demonstrate the capabilities of the method, results of multiple analyses of several FD&C Yellow No. 6 samples are presented, and results from corresponding analyses by an AOAC ion exchange LC method and by a thin layer chromatographic method are compared with results found with the new reverse phase LC method.
Composition and Protein Efficiency Ratio of Meat Samples Partially Defatted with Petroleum Ether, Acetone, or Ethyl Ether
Authors: Happich Muriel L , Ackerman Stanley , Miller Arthur J , Swift Clifton E , Gumbmann Michael R 
Published: February 2020

Abstract
Freeze-dried beef samples were partially defatted with either petroleum ether, acetone, or ethyl ether before determination of protein efficiency ratio (PER) to study the extraction effects on the composition and protein nutritional quality of the extracted beef. Defatting a protein source, such as meat or a meat product, may often be necessary to produce a test diet that contains 10% protein and 8% fat. Amino acid, carnosine, anserine, creatine, creatinine, inosine, and proximate com- 5 positions%ere determined on the extracted samples. Resulting data were compared to the composition and PER data of the beef that had no solvent treatment. Although the chemical analysis data from the study showed some variation between the proteins and other nitrogenous components of the unextracted and the extracted beef, these variations were too small to affect the protein nutritional quality of the beef as measured by PER.
Liquid Chromatographic Cleanup and Determination of Low Levels of Vitamin D3 in Sheep Plasma
Authors: Cohen Huguette , Hidiroglou Michel , Keough Michael 
Published: February 2020

Abstract
A liquid chromatographic (LC) method is described for the determination of vitamin D3 in sheep plasma. Samples are extracted by one of 2 different methods, depending on the concentration of vitamin D&gt; The samples are purified by using either a Sep-Pak silica cartridge or a small alumina column, followed by additional cleanup on a Metalsorb LC column. Final analysis was carried out on a 5 μm C18 column using a radial compression separation system with an acetonitrile-methanol solvent system. Vitamin D3 was completely resolved from any interfering compounds in the plasma; total run time was less than 15 min, using a variable wavelength detector set at 264 nm. The method was successfully applied to samples at levels of 1-10 ng added vitamin D3/mL sheep plasma, with recoveries in the range 90-97%.
Gas Chromatographic Determination of Pentachlorophenol in Gelatin
Authors: Borsetti Arnold P , Thurston Lee S 
Published: February 2020

Abstract
A method is described for the determination of pentachlorophenol (PCP) in gelatin. The method employs acid and heat to hydrolyze the gelatin matrix, a base partition and wash for separation and cleanup, and a reacidification and extraction with hexane for direct determination of PCP, without preparation of a derivative, using gas chromatography (GC) with a 1% SP-1240DA liquid phase and a 63Ni electron capture detector. Recoveries averaged 106% for fortifications between 0.02 and 1.0 ppm. The limit of quantitation is 20 ppb. The limit of detection is 4-6 ppb. The method, which has undergone a successful intralaboratory trial, is simple and rapid, and requires only general laboratory reagents and equipment. GC of the acetate derivative of PCP is used for confirmation of identity.