bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Confirmation of Diethylstilbestrol Residues in Beef Liver by Gas Chromatography-Mass Spectrometry
Authors: Day Edgar W , Vanatta Lynn E , Sieck Robert F 
Published: February 2020

Abstract
A confirmatory test for the presence of the growth-promoting hormone, diethylstilbestrol (DES), in beef liver is described. Samples are subjected to a published electron capture gas chromatographic method that involves the formation and measurement of the bis-dichloroacetyl derivative of DES. The presence of the derivative is then confirmed by gas chromatography-mass spectrometry, using a repetitive scanning technique to maximize response. The isotope pattern of the tetrachlorinated molecular ion greatly facilitates the confirmation.
Estimation of Glycoalkaloids as Solasodine in Solanum laciniatum
Authors: Karawya Mohamed S , Ghourab Mohamed G , Elrakhawy Faten H 
Published: February 2020

Abstract
Solasodine is isolated from Solatium laciniatum leaves by a rapid, one-step procedure which involves extraction and hydrolysis of the glycoalkaloids. The resulting steroidal aglycone is directly estimated by the formation of a colored complex with bromocresol green. The method is applicable to concentrations of 25–125 µg solasodine/7 ml.
The Analysis of Pharmaceuticals by Combined Gas Chromatography-Mass Spectrometry. I. The Analysis of a Medicated Aerosol Spray
Authors: Sheinin Eric B , Benson Walter R , Brannon Wilson L , Schwartzman George 
Published: February 2020

Abstract
A medicated aerosol product was qualitatively analyzed by combined gas chromatography-mass spectrometry. The data were processed by a minicomputer. Ten of the 11 peaks in the gas chromatogram were identified with the assistance of the National Institutes of Health/Division of Computer Research and Technology/Chemical Information System mass spectral search system. The unidentified peak is probably a member of the terpene class. The aerosol propellants were also partially analyzed by infrared spectrophotometry.
Chemical Ionization Mass Spectrometry of N-Methylcarbamate Insecticides, Some of Their Metabolites, and Related Compounds
Authors: Holmstead Roy L , Casida John E 
Published: February 2020

Abstract
The chemical ionization (CI) mass spectra with methane as the reagent gas are reported for 25 N-methylcarbamato insecticides or related compounds. The [M + 1]+ ions in the CI spectra are larger than the parent ions in the corresponding electron impact (EI) spectra of N-methyl- and N,N-dimethylcarbamates, but the contrary is true with N-hydroxymethylcarbamates. CI but not EI fragmentation of substituted- phenyl N-hydroxymethylcarbamates [ROC(0)NHCH2OH] appears to involve a 4-membered [ROC(0)NHCH2]+ intermediate which rearranges to give a [ROCH2]+ fragment. Other fragmentations unique to the CI spectra are also discussed.
Determination of Coumaphos and Its Oxygen Analog in Eggs by In Situ Fluorometry
Authors: Zakrevsky Jean-Guy , Mallet Victorin N 
Published: February 2020

Abstract
A method is reported for the simultaneous determination of coumaphos (O,0-diethyI 0-(3-chloro-4-methyl-2-oxo-2H-l-benzopyran-7-yl) phosphorothioate) and its oxygen analog, Coroxon, in eggs in the ppb range. The residues are extracted with acetone and chloroform. The extract is purified by liquid-liquid partition followed by column chromatography and then by 2-dimensional thin layer chromatography. The fluorescence is measured directly on the chromatogram.
Gas-Liquid Chromatographic Method for Determining Ethylenethiourea in Plants
Authors: Nash Ralph G 
Published: February 2020

Abstract
An additional gas-liquid chromatographic method has been developed for determining ethylenethiourea (ETU) in plants. Two ETU derivatives, 2-(o-chlorobenzy Ithio)-1-(pentafluorobenzoyl)-2-imidazoline and 2-(benzylthio)-1-(pentafluorobenzoyl)-2-imidazoline, can be prepared from the same extract, which allows confirmation of the presence and quantity of ETU at &gt;5 ppb. No degradation of the parent fungicides to ETU during benzylation or ochlorobenzylation was observed.
Collaborative Study of the Milko-Tester Method for Measuring Fat in Homogenized and Unhomogenized Milk
Authors: Shipe W Frank , Senyk Gary F 
Published: February 2020

Abstract
The Mark III Industrial Model Milko-tester was evaluated to determine its reliability for testing both unhomogenized and homogenized milk samples. Six laboratories participated in 2 trials. In the first trial, the range among laboratories for homogenized milk was 0.29% and unhomogenized milk 0.34%. This variation was apparently due to inaccurate calibrations. In the second trial, 2 calibration standards were used for each type of milk and the range was reduced to 0.04% for homogenized milk and 0.05% for unhomogenized milk. The standard deviations for unhomogenized and homogenized milk were 0.008 and 0.010 for trial 1 and 0.005 and 0.005 for trial 2, respectively. The official first action automated method I for the determination of fat in raw, unhomogenized milk has been expanded to include the determination of fat in homogenized milk by the use of the Mark III Industrial Model Milko-tester.
Determination of Benzaldehyde in Wines and Amyl Acetate and Isoamyl Acetate in Liqueurs by Gas-Liquid Chromatography and Confirmation by Mass Spectroscopy
Authors: Martin Glenn E , Buscemi Peter C , Butts Boyd B 
Published: February 2020

Abstract
Liquid-liquid extraction was carried out prior to gas-liquid chromatographic (GLC) determination of amyl and isoamyl acetate in alcoholic beverages. The concentrations of amyl acetate and isoamyl acetate ranged from 4 to 29 and 2.5 to 322 ppm, respectively. Recovery studies for isoamyl and amyl acetate were carried out; these compounds were recovered at 90 and 92%, respectively. A liquid-liquid extraction also was carried out prior to the GLC determination of benzaldehyde. When chloroform was used in the liquid extraction, the results obtained by the GLC procedure compared favorably in most cases with those obtained by the ultraviolet spectrophotometric procedure. In the GLC method the benzaldehyde varied from 5 to 150 ppm for both imported and natural wines. The compounds in the effluent from the chromatograph, namely, amyl acetate, isoamyl acetate, and benzaldehyde, were confirmed by mass spectroscopy.
Identification of d- or di-∝-Tocopherol in Pharmaceuticals, Food Supplements, or Feed Supplements: A Collaborative Study
Authors: Ames Stanley R , Drury Emma-Jane E 
Published: February 2020

Abstract
A collaborative study was conducted to evaluate a method for identifying d- or dl-∝-tocopherol in pharmaceuticals, food supplements, or feed supplements. The sample is extracted and saponified, the extraneous color is removed by chromatography, and the sample is assayed for vitamin E. Optical rotations are determined before and after formation of the ferricyanide oxidation product. The specific optical rotation of the oxidation product is negligible for the dJ-form and +25.5° for the d-form. Statistical analysis of the data reported by 8 collaborators for the standard d-∝-tocopheryl acetate and for 6 unknown samples indicates a significant interaction between laboratories and samples. The mean coefficients of variation among laboratories for the determinations of the corrected specific optical rotation of the standard and the rotation ratio for the unknown samples containing d-∝-tocopherol were 11.7 and 21.6%, respectively, for all laboratories and 5.8 and 11.8%, respectively, for experienced laboratories. This identification test for vitamin E is acceptable for determining the form of vitamin E as either d or dl, but is not acceptable for accurately determining mixtures of the 2 forms. The method has been adopted as official first action for the identification of d- or dl-∝-tocopherol.
A Specific Method for the Determination of Provitamin A Carotenoids in Orange Juice
Authors: Reeder Samuel K , Park Gary L 
Published: February 2020

Abstract
A method has been developed for rapidly determining the amounts of ∝-carotene, β-carotene, and cryptoxanthin in orange juice. The procedure includes extraction, saponification, and high-speed liquid chromatography. Limits of detection for the 3 carotenoids are 0.04, 0.02, and 0.04 μg/ml, respectively.
Collaborative Study of the Determination of Available Lysine in Proteins and Feeds
Authors: Couch J Russell 
Published: February 2020

Abstract
In the proposed method l-fluoro-2,4-dinitrobenzene (DNFB) is reacted with the free ɛ-amino groups in protein to form DNFB-ɛ-amino lysine which is stable to acid hydrolysis. The sample is acid hydrolyzed and unavailable lysine is determined with an amino acid analyzer; total lysine is determined on the untreated sample. The available lysine, which was bound by DNFB, is determined by difference. The available lysine has been determined in 3 samples of 44% protein soybean meal by 5 collaborators, following the method outlined. The range for available lysine in reference standard 1 was 2.02–2.14%, in reference standard 2, 2.59–2.73% and in reference standard 3, 0.55–0.91%. The method has been adopted as official first action.
Chromatographic Analysis of 4,4’- (Diazoamino) -dibenzenesulfonic Acid in FD&C Yellow No. 6
Authors: Bailey John E , Cox Elizabeth A 
Published: February 2020

Abstract
4,4’- (Diazoamino) -dibenzenesulfonic acid (DAADBSA) has been found in samples of FD&C Yellow No. 6 that were submitted for certification. The material was detected by conventional elution chromatography and highpressure liquid chromatography (HPLC). DAADBSA is synthesized by diazotizing sulfanilic acid. The diazonium compound is then coupled with undiazotized sulfanilic acid in the presence of sodium acetate. A method for the quantitative determination of DAADBSA in FD&C Yellow No. 6 using HPLC is presented. An untested method of correcting for interfering compounds is also described.
A Convenient Thin Layer Chromatographic Cleanup Procedure for Screening Several Mycotoxins in Oils
Authors: Hagan Susie N , Tietjen William H 
Published: February 2020

Abstract
A thin layer chromatographic cleanup development with benzene-hexane (34+1) effectively removed lipids and some contaminants from mixtures of mycotoxins in corn oil, olive oil, peanut oil, soybean oil, and seed extracts. A second development in the same direction as the first, using toluene-ethyl acetate-formic acid ( 6+3+1 ) or benzene-acetic acid (9+l), separated the mycotoxins. Satisfactory separation was achieved for commercial oils spiked with sterigmatocystin, zearalenone, ochratoxins A, B, and C, and anatoxins B1 B2, Gl and G2. This technique permits detection of 5 ppb aflatoxin B1 in corn.
Production of Sterigmatocystin
Authors: Steyn Martin , Rabie Chris J 
Published: February 2020

Abstract
A procedure for the isolation of pure sterigmatocystin is described. It involves cultivation of an appropriate fungus on sterile maize, and extraction and column chromatographic purification of the crude extract. With this method sterigmatocystin may be obtained at a fraction of its commercial cost. Aspergillus versicolor seemed to be the best producer (5–12 g/kg) in 250 ml Erlenmeyer flasks. The yield dropped markedly with increasing flask size.
Safety Evaluation Concepts
Authors: Golberg Leon 
Published: February 2020

Abstract
The approach to safety evaluation is strongly influenced by the standard of safety to which one aspires. Practical considerations demand that realistic limits be set to the attainable assurances of freedom from anticipated hazard under actual conditions of use of a product. The fact is that, in the interests of consumer health, more can be expected from a flexible, intelligent, and experienced approach to safety evaluation than from efforts at conformity with a set of rigidly standardized requirements that are theoretically all-encompassing. Establishment of safety demands a wide background of information about the properties and likely uses of the product; above all, knowledge of the chemical composition of the product and its impurities, degradation products, and metabolites is essential. Lack of such information is a frequent source of errors in safety evaluation. Based on a secure foundation of this sort, a program of investigations may be designed, aimed at establishing the basic biological properties of the material. Determination of the metabolic dynamics of the principal chemical agent or agents makes possible the emergence of a clear picture of the behavior of the compound(s) in the body and paves the way for more specialized studies of long term toxicity, carcinogenicity, effects on reproduction and teratogenesis, and investigations of multitest mutagenic potential. Emphasis is laid on the problems of interpretation of results in terms of hazard to man and on the crucial contribution that experience of human exposure can make toward assuring safety-inuse. Decisions on acceptable risk are the joint responsibility of many individuals but an essential element in reaching such decisions is contributed by the depth of understanding and broad experience of the toxicologist.
Acute and Prolonged Toxicity Tests
Authors: Loomis Ted A 
Published: February 2020

Abstract
An answer to the question of whether acute and prolonged toxicity tests are good candidates for standardization is developed by reviewing (1) the factors that are presumed to influence the results of these tests and (2) the collaborative studies that have been reported in the literature. In regard to acute toxicity tests it is clear that competent laboratories give due consideration for the control of factors that are known to influence these tests. Also competent laboratories using their own procedures provide reliable results, even though the procedures vary from laboratory to laboratory. In regard to prolonged toxicity tests there are no examples of controlled collaborative investigations which could be used to evaluate interlaboratory variation and its relation to the protocols involved. It is recommended that guidelines rather than rigid protocols would be an appropriate approach for improving the quality and accuracy of these toxicologic tests. Examples of such guidelines are given.
Pathology: Studies of Chronic Toxicity and Carcinogenicity
Authors: Newberne Paul M 
Published: February 2020

Abstract
Safety evaluation of chemicals in use or destined for use by humans is a complex endeavor which requires accurate analytical chemical results, extensive animal studies, and thoughtful interpretation of the data. Especially difficult are attempts to extrapolate the animal data to man. The analytical chemist can base many of his conclusions on data concerning quantity; the toxicologist cannot. The analytical chemist works very hard for an answer, but when he gets it, his task is usually completed. When the toxicologist gets an answer from a given experiment, his problems have just started; he must attempt to interpret the data and, even more difficult, to extrapolate the results of animal data to man. Thus, accurate analysis of chemicals and trace substances in biological tissues form the foundation of the work of the toxicologist. A closer association between analytical chemists and toxicologists should prove beneficial to both and to the progress of science.
Reproduction and Teratogenesis: Current Methods and Suggested Improvements
Authors: Wilson James G 
Published: February 2020

Abstract
The risks to human reproduction, particularly in regard to possible induction of birth defects, from present levels of environmental chemicals are thought to be low but in need of closer scrutiny than is now the case. Methods currently used to estimate the hazards to reproduction of new chemicals and drugs are reviewed and some shortcomings and potential sources of error are noted. Specific suggestions are made for improving existing methodology. In addition to the widely used treatment span encompassing all or most of the period of organogenesis, it is proposed that some exposure periods of shorter duration be added to avert possibly adaptative changes in maternal homeostatic systems. Greater diversity of test animals, beyond the rodent-rabbit species largely used today, is urged with the objective of better matching metabolic pathways in a test animal to those of man. The demonstration of an embryotoxicity effect-level must be regarded as essential in all tests, and once found this level should be used as the basis of extrapolating downward to find an acceptable tolerance level of dosage. More attention should be focused on postnatal functional evaluation after prenatal and perinatal exposure of test animals to environmental chemicals, especially those that might interfere with the maturation of the central nervous system, endocrine glands, and immunological mechanisms. The use of nonhuman primates should be reserved for the testing of drugs essential for use during human pregnancy or those likely to be taken inadvertently during early pregnancy, because of the scarcity of such animals and the high costs of doing meaningful tests with them.
Test Systems for Assessing Mutagenic Potential of Chemical Substances
Authors: Flamm W Gary 
Published: February 2020

Abstract
The first report that certain chemicals have the potential of inducing heritable effects (mutation) appeared in the mid-1940’s. Two decades passed before this and subsequent observations were translated into a concern that some of the chemicals to which we are exposed may constitute a hazard to man’s genetic material and hence a threat to future generations of individuals. Such concern has led to the gradual evolution of the newest subdiscipline of toxicology, genetic toxicology. This subdiscipline is still young and faces many challenges in terms of developing sound toxicologic approaches for meeting specific evaluation needs in the interest of public health. This paper describes the current status of efforts in genetic toxicology and the types of steps which must be taken in order to begin to meet the needs and requirements of regulatory agencies.
Summary
Authors: Borzelleca Joseph F 
Published: February 2020

Abstract
Two kinds of problems associated with developing standardized procedures for the safety evaluation of new compounds are identified. The first of these is the question of the desirability of using such standard methods. It is concluded that a basic set of procedures is to be recommended, but this should be supplemented with special tests as may be indicated. The second problem is connected with the technical difficulties of any given type of assay and is normally dealt with in terms of the state of the art at the time. Assays by the inhalation route tend to be custom designed and do not follow standard protocols. One of the causes of this situation is the propensity of individual investigators to design de novo the equipment used to effect exposure of animals to airborne substances. Second, some confusion exists because investigators do not always appreciate that the concentration-time product is not the same as the true dose received by the exposed subjects and this may lead to anomalies when dose-response relationships are being characterized. It is suggested that interlaboratory studies be undertaken to ascertain the variability that might be expected in independent assays of inhalation toxicity.
Bioaccumulation of Chlorinated Paraffin Residues in Fish Fed Chlorowax 500C
Authors: Lombardo Pasquale , Dennison J Lawrence , Johnson W Waynon 
Published: February 2020

Abstract
Fingerling rainbow trout were fed a diet fortified with 10 ppm Chlorowax 500C, a chlorinated paraffin, for up to 82 days. Chlorinated paraffin residues as high as 1.1 ppm (tissue basis) were found. Recoveries from fortified fish tissue were greater than 92%, and the method sensitivity (tissue basis) is at least 0.5 ppm. Ultraviolet irradiation of the sample extracts and microcoulometric gas chromatography minimized interferences. No gross toxicological effects were noted in the experimental fish, although their weight gain was less than that of the controls.
A Review of Bromine Determination in Foods
Authors: Getzendaner Milton E 
Published: February 2020

Abstract
Organic compounds containing bromine, including methyl bromide, ethylene dibromide, and l,2-dibromo-3-chloropropane, have been used extensively for the fumigation of foods, or soils in which foods grow, making it necessary to determine residues of bromine and bromine-containing organic compounds. A large number of methods for the determination of bromine in foods, as organic, inorganic, and combined total bromide, have been developed. In methods for organic bromide, the bromine is converted to the inorganic form for measurement by titration, photometry, or other means. In recent years, instrumental methods have been developed in which the total bromine in the sample is determined, regardless of the state in which it exists. X-ray fluorescence and neutron activation analysis are the 2 instrumental methods used most widely. Residue data are presented for some typical bromine-containing samples.
Thin Layer Chromatographic Separation and Spectrodensitometric Determination of Higher and Lower Sulfonated Subsidiary Dyes in FD&C Yellow No. 6
Authors: Bell Sandra 
Published: February 2020

Abstract
A thin layer chromatographic method is presented by which higher and lower sulfonated subsidiary dyes are simultaneously separated from FD&C Yellow No. 6. After separation, the colors are quantitated directly, using a spectrodensitometer. Recoveries of 1, 2, and 5% of added 1-(4-sulfophenylazo)-2-naphthol-3,6-disulfonic acid ranged from 92 to 111%. Recoveries of 1, 2, and 5% of added l-(4-sulfophenylazo)-2-naphthol ranged from 90 to 110%.
High-Pressure Liquid Chromatographic Method for the Determination of Patulin in Apple Butter
Authors: Ware George M 
Published: February 2020

Abstract
Patulin is extracted from apple butter samples with ethyl acetate and the extract is cleaned up on a silica gel column, using benzene-ethyl acetate (75+25) as the eluant. High-pressure liquid chromatography, using a 25 cm Zorbax-Sil column, isooctane-ethyl ether-acetic acid (750+250+0.5) as the mobile solvent, and a 254 nm ultraviolet detector, is used for the determinative step. Under these conditions, patulin is eluted before 5-hydroxymethylfurfural, a component of apple butter which interferes with other liquid chromatographic and thin layer chromatographic methods. Recoveries of patulin added at levels of 34.6, 138.4, and 276.8 μg/kg ranged from 89.0 to 112.1%.
Fluorometric Measurement of Aflatoxin Adsorbed on Florisil in Minicolumns
Authors: Velasco James 
Published: February 2020

Abstract
Filter fluorometers have been adapted to measure the fluorescence intensity of aflatoxin adsorbed on a Florisil layer in minicolumns. The relationship between concentration and intensity is near linear in the aflatoxin range from 10 to 100 ng. Although individual aflatoxin fractions cannot be resolved, since the measure is one of total intensity, fluorometric measurements advance the minicolumn screening procedure to a semiquantitative level. The detection of 1 ng aflatoxin B1 is well within the limits of a filter fluorometer with a photomultiplier detector. A precision, expressed as percent coefficient of variation, ranging from 1.2 to 4.2%, was obtained for standard B1 columns.