bluuebunny/crossref_metadata_2025 huggingface dataset:
Are economists Kings? Economic evidence and discretionary assessments at the UK utility regulatory agencies
Authors: Mantzari Despoina
Published: February 2020

UK sectoral regulatory authorities are hybrid communities of, among others, lawyers and economists. Since the liberalization of essential services, expert economists enjoy broad discretionary powers in advancing the agencies’ broad statutory objectives. Yet, despite the significant societal impact of economic regulation, existing scholarship in the fields of competition law and regulation and public law has, with very few exceptions, disregarded these actors and the very essence of their work. This article aims to address this gap in the literature by blending theoretical with empirical insights deriving from 14 semi-structured elite interviews with regulatory economists in the regulatory agencies for energy (Office for Gas and Electricity Markets), telecoms (Office for Communications), and water (Office of Water Services). It explores the increased reliance on economics in the regulatory decision-making process and the impact this has had on the authorities’ decision-making and discretion, when making complex trade-offs between the various goals of the regulatory enterprise. In doing so, it puts forward a theoretical framework inspired by Craig Parsons’ typology of political action so as to identify and examine the nature and scope of the constraints that inform and shape the influence of economics in the exercise of regulatory discretion. This endeavour is significant in the sense that it is the first of its kind and, in that it provides a normative framework of analysis that can be applied in other areas of regulation heavily infused with and influenced by economic evidence and analysis, such as ‘pure’ competition law enforcement by both sectoral and competition authorities.
Allyl Isothiocyanate in Mustard Seed
Authors: Andersen Donald L
Published: February 2020

A new GLC method for the determination of allyl isothiocyanate in mustard seed was compared to a method of the Midwest Research Institute and to a combination of the AOAC official method and the proposed method. Twelve collaborators compared the AOAC method and the GLC method, using whole mustard seeds. Each collaborator assayed three seed portions by both methods. The range, standard deviation, and coefficient of variation are less for each seed portion by the proposed than by the official method. The average recovery value of allyl isothiocyanate in the prepared standard solutions is lower, using the proposed GLC procedure, but seed assay values are significantly and consistently higher for each seed portion when compared with the results for the AOAC method. Reports from the collaborators also indicate that the proposed method is rugged, as the GLC column preparation was subjected to many changes. It is recommended that the GLC method be adopted as official first action.
Isolation and Identification of Lysergic Acid Amide and Isolysergic Acid Amide as the Principal Ergoline Alkaloids in Argyreia nervosa, a Tropical Wood Rose
Authors: Miller Michael D
Published: February 2020

Lysergic acid amide and isolysergic acid amide have been extracted and isolated from the seed of Hawaiian baby wood rose. The ergoline alkaloids were identified by TLC, melting point determination, and UV and IR spectrophotometry.
GLC Determination of Quinaldine Residue in Fish
Authors: Allen John L , Sills Joe B
Published: February 2020

A procedure for the determination of quinaldine residue in various fish tissues is described. Homogenized tissues are extracted with hexane-ethyl ether, the extracts are concentrated by partitioning through 0.1N sulfuric acid, and the residues are measured by alkali flame ionization gas chromatography. Muscle tissues containing from 0.01 to 10.0 ppm quinaldine were successfully analyzed with recoveries from 75 to 100%.
GLC Determination of Butylated Hydroxyanisole and Butylated Hydroxytoluene in Breakfast Cereals
Authors: Takahashi David M
Published: February 2020

Eighteen laboratories studied the AOAC official first action method for GLC determination of BHA and BHT in corn and rice ready-toeat breakfast cereals. Recoveries obtained were superior to those from the previous collaborative study. Corn cereal spiked with 29.5 p pm BHA and 30.6 p pm BHT gave 98 and 101% average recoveries, respectively. Rice cereal spiked with 25.2 ppm BHA and 25.6 ppm BHT gave 98 and 100% average recoveries, respectively. The method, as amended, is recommended for adoption as official final action.
Comparison of Drained Weight Determinations by US and ISO Screens
Authors: Lamb Frank C , Farrow R P
Published: February 2020

US and ISO screen designations are compared for drained weight determinations on canned fruits and vegetables. It is concluded that there is no practical difference between the US No. 8 and 2 mesh screens, and ISO No. 7 and 7/6″ screens, respectively.
Rotary Separatory Funnel Rack and Shaker for Determination of Molybdenum in Plants and Soils
Authors: Doran J W , Martens D C
Published: February 2020

A rotary separatory funnel rack and shaker for determination of plant and soil molybdenum is described. The separatory funnel rack allows rotation around a fixed axis as well as shaking of 20 separatory funnels. Utilization of the funnel rack and shaking adapters reduces procedural time for molybdenum analyses by decreasing time of shaking and addition of reagents.
Direct Determination of Fluoride in Phosphate Materials in Mineral Feeds with the Fluoride Ion Activity Electrode
Authors: Tušl Jan
Published: February 2020

The fluoride electrode was used for the direct determination of fluoride in various basic phosphates used as mineral feed ingredients. The results were in good agreement with those obtained with the alizarin complexonate reagent after separation of fluoride from the sample by diffusion or microdistillation of the sample extract. The described method is very suitable for precise routine analyses.
Total Nitrogen Methods—Applicable to All Fertilizer Samples
Authors: Rexroad Paul R , Krause Gary F
Published: February 2020

An extensive collaborative study was conducted to evaluate a comprehensive nitrogen method and a Raney powder method for acceptance as official methods. Twenty-nine laboratories participated; 10 samples were used and the new methods were compared to the official method, 2.045 (sulfuric-salicylic acid). Evaluation of the data and overall consideration lead to the recommendation that both new methods be adopted as official. It is recommended that 2.047 (reduced iron) and 2.049 (chromium powder) be deleted as official methods.
Comparison of Elemental Composition of Pistol Bullets by Atomic Absorption: Preliminary Study
Authors: Brunelle R L , Hoffman C M , Snow K B
Published: February 2020

A method is presented for the determination of antimony, copper, bismuth, and silver in bullet leads by atomic absorption. Interference in the determination of these elements from high lead concentrations was studied. Bullets of the same caliber, produced by 3 different manufacturers, can be distinguished based on the antimony concentration alone. Measurable variations in the concentrations of antimony, copper, bismuth, and silver exist and can be used to estimate batch differences in lead produced by the same manufacturer.
Collaborative Study of an Electrometric Method for Determination of pH of Cacao Products
Authors: Iverson John L
Published: February 2020

The sample is dispersed in hot water, filtered, and cooled and the pH of the filtrate is measured with a pH meter standardized against standard buffers. Results of a collaborative study show good agreement between samples and laboratories. It is recommended that the method be adopted as official first action.
Stone Cell Count Method and Stone Cell Group Method for Estimating Shell in Chocolate Products
Authors: Jackson Manion M
Published: February 2020

Per cent shell in the chocolate component of cocoa and similar products is determined on the basis of an average stone cell content of 9340 stone cells/mg dry fat-free 250 mesh shell. The sample is weighed and diluted to a weighed suspension in 60% (v/v) glycerine. The total number of stone cells in a weighed drop on a slide are counted microscopically at 100–200X. The per cent shell chocolate component is then calculated. Seven cocoa samples were analyzed and their results were compared to previous results obtained by the spiral vessel count and pectic acid methods. Average results for shell in the chocolate component were 6.5% for the stone cell count method, 6.6% for the spiral vessel count method, and 6.4% for the pectic acid method. Six collaborators studied 4 cocoa samples and compared 3 methods: the stone cell count method, the calculation procedure of Van Brederode and Reeskamp, and the stone cell group method. Five varied less than 1 standard deviation from the average for 3 samples and 4 collaborators were within 1 standard deviation in the stone cell count method for the remaining sample. The stone cell count method is recommended for adoption as official first action for the analysis of shell for cocoa, cocoa press cake, chocolate liquor, and expeller cake; the group method is recommended for other chocolate products.
Collaborative Study of Extraction Methods for Fluorometric Assay of Riboflavin
Authors: Ritter E De
Published: February 2020

The AOAC fluorometric method for riboflavin is not applicable in the presence of materials that adsorb riboflavin. Deutsch et al. described a modified extraction with methanol- pyridine-water-glacial acetic acid (30 + 10 + 1 0 + 1 ) which yields higher recovery of riboflavin from samples containing interfering adsorbents. A collaborative study of 4 samples confirmed the more efficient extraction of riboflavin by the modified method. The study also shows that the permanganate oxidation step is unnecessary for extracts of relatively high potency products such as concentrates, premixes, and multivitamin supplements. It is recommended that an alternative method be adopted as official first action, with the following modifications: extracting with the new solvent mixture, omitting the permanganate treatment of the extract, and measuring the fluorescence of the standard riboflavin solution separately rather than after addition to an aliquot of sample solution.
New Method for the Extraction of Light Filth from Whole and Granulated Nutmeats
Authors: Gecan John S , Howarth Diane J , Brickey Paris M
Published: February 2020

A new method has been developed which is applicable to all nutmeats, with or without testa, either raw, dry, or oil roasted. Nutmeats are defatted by a 10 min boiling in chloroform (pecans require 3 defattings), after which the solvent is removed by aspiration and an isopropanol rinse. Following a short boiling deaeration and acid hydrolysis, light filth elements are extracted with mineral oil from a mixture of 60% ethanol and calcium chloride. Collaborative trials by the proposed method for nutmeats (except pecans) yielded significantly cleaner extraction papers and better recoveries of all light filth spike elements than by the official method. In addition, the proposed method resulted in reductions of coefficients of variation ranging from 47 to 93% of that for the official method. The modification for pecans, included in this method, required more extensive defatting and also resulted in improved light filth recoveries and reductions in coefficients of variation. Not all varieties of nutmeats were collaboratively studied; however, intralaboratory recovery trials on these nutmeats proved the proposed method superior to the official methods. The method is recommended for adoption as official first.
Extraction of Light Filth from Raw and Processed Wheat Germ
Authors: Roaf Andree L , Brickey Paris M , Dent Russell G
Published: February 2020

A method developed for the extraction of light filth from raw and processed wheat germ utilizes chloroform defatting and acid hydrolysis followed by wet sieving. Light filth is extracted with mineral oil from a hot ethanol or isopropanol solution. The collaborative study resulted in 90, 89, and 84% average recoveries of spike insect fragments, rodent hairs, and adult insects, respectively. The method is recommended for adoption as official first action.
Extraction and Spectrophotometry Determination of Benzthiazide, Hydrochlorothiazide, and Hydroflumethiazide in Pharmaceuticals
Authors: Fazzari F Raymond
Published: February 2020

A method has been developed for the determination of benzthiazide, hydrochlorothiazide, and hydroflumethiazide in pharmaceuticals. The procedure is rapid and specific and employs established separation techniques. The active ingredient is eluted from a basic Celite column with an acetic acid-ether solvent and extracted from the organic phase into NaOH for the spectrophotometric determination.
Determination of Aflatoxin in Cottonseed by Ferric Hydroxide Gel Cleanup
Authors: Velasco James
Published: February 2020

The procedure for determination of aflatoxin in cottonseed has been simplified by removal of interfering gossypol pigments with ferric hydroxide gel. The need for purification of the aflatoxin fractions through silica gel columns is eliminated, thereby reducing the time and cost of analysis. Greater amounts of aflatoxin Bi are recovered by this method than by the official AOAC method.
Determination of Patulin in Apple Juice
Authors: Pohland A E , Sanders K , Thorpe C W
Published: February 2020

A method is described for the quantitative analysis of patulin in apple juice involving ethyl acetate extraction followed by derivatization of the patulin and subsequent GLC analysis of the derivative. Preparation of 3 derivatives, the silyl ether, acetate, and chloroacetate, is described. Using the acetate derivative and the hydrogen flame detector, recoveries of patulin in spiked apple juice are 90% or better and the detection limit is about 0.7 μg/ml
Quantitation of Ammonium Glycyrrhizinate by Gas-Liquid Chromatography of the Silyl Ether Ester Derivative of the Aglycone
Authors: Larry Damon , Fuller Michael J , Harrill Prince G
Published: February 2020

GLC method has been developed for the quantitation of ammonium glycyrrhizinate as the aglycone, glycyrrhetic acid. The aglycone is freed from the sugar moiety in a dioxanewater mixture, using a well established acid hydrolysis procedure. The hydrolysate is extracted with chloroform, an aliquot is dried on a steam bath, and the residue is treated with pyridine - trimethylchlorosilane - N,0 - bis (trimethylsilyl)acetamide reagent. The reacted product and internal standard are then chromatographed on a column of 1.5% OV-1 on Gas Chrom Q. Recoveries from both water and sodas containing caramel averaged 87%.
Thin Layer Chromatographic Detection of Carbamate and Phenylurea Pesticide Residues in Natural Waters
Authors: El-Dib M A
Published: February 2020

Detection, separation, and identification of N-phenyl, N-methylcarbamates and related ureas in natural waters could be achieved on acidic silica plates. Six solvent systems and selective chromogenic agents have been found suitable according to compounds in question. Residues of chlorinated or organophosphorus pesticides did not interfere with this TLC procedure.
Method for Separating Polychlorinated Biphenyls from DDT and Its Analogs
Authors: Armour Judith A , Burke Jerry A
Published: February 2020

Polychlorinated biphenyls are separated from DDT and i t s analogs and other common chlorinated pesticides by column chromatography on silicic acid-Celite. PCB are eluted from the column with petroleum ether prior to elution of pesticides with a mixture of acetonitrile, hexane, and methylene chloride. Determination of PCB and pesticides can be made o,n the separate column eluates without cross interference. The method is applicable to samples prepared by multipesticide residue methodology and should be applicable to sample extracts prepared for gas chromatography by usual procedures. Recoveries of Aroclors 1254 and 1260 and of several chlorinated pesticides through the separation method ranged from 76 to 100% and 80 to 107%, respectively.
Microcrystalline Identification of Phenothiazine-Type Tranquilizers. II. Collaborative Study
Authors: Andres Carolyn N
Published: February 2020

The method for the microchemical identification of 12 related phenothiazine-type tranquilizers was studied collaboratively. It is recommended that the following most characteristic crystal tests be adopted as official first action: acetophenazine-picric acid, chloroprothixene-ammonium reineckate, fluphenazine-picric acid, mepazine-ammonium thiocyanate, mepazine-gold chloride, promazinegold chloride, promethazine-ammonium reineckate, promethazine-platinum bromide, propiomazine-ammonium reineckate, and trifluoperazine- stannous chloride.
Testing Germicidal Spray Products for Tuberculocidal Activity
Authors: Ortenzio L F
Published: February 2020

Certain procedural changes were recommended to update the following methods: phenol coefficient—5.001(a)(1), (4)(b), (4)(c), 5.002(d), 5.003, 5.005, and 5.006; water disinfectants for swimming pools—5.042; and tuberculocidal activity—5.048(b). Method 5.042 was also recommended for official final action status. Studies will continue on the possibility of adding a procedure for tuberculocidal activity to the germicidal spray test.
Moisture in Cheese by Gas Chromatography and by Karl Fischer Titrimetry
Authors: Strange Theron E
Published: February 2020

Anhydrous 2-propanol effectively removes water from cheese during blending in a tightly closed blender jar. The water is determined in the resulting extract by GLC or by Karl Fischer titration, and methods based on both procedures are reported. In the GLC method water was quantitated by incorporating an internal standard of ethanol and by using a Porapak Q or Porapak K column and thermal conductivity detector. The Karl Fischer titration method is essentially as previously reported. The 2-propanol extract of water is introduced into the titrating cell from a buret and, following the titration, the contents of the cell are removed by suction. Comparative results for moisture in several types of cheese are reported.
Review of the Application of Nuclear Magnetic Resonance Spectroscopy in Pesticide Analysis
Authors: Keith Lawrence H , Alford Ann L
Published: February 2020

Although the role of NMR spectroscopy in the area of pesticide chemistry is small relative to its usage in other areas of chemistry, the continued and expanding use of NMR spectroscopy by pesticide chemists has aroused a great deal of current interest in this subject. Accordingly, this review has included all references to date where NMR spectroscopy has been used for structural elucidation of pesticide metabolites and degradation products, for structural confirmation of new pesticides, or for product analysis of existing ones.
Rapid Colorimetric Method for Estimation of Ferbam and Ziram Residues on Grains
Authors: Rangaswamy J R , Poornima P , Majumder S K
Published: February 2020

The rapid colorimetric method for thiram reported earlier has been slightly modified and extended to the analysis of 2 dithiocarbamates (ferbam and ziram). The proposed method is applicable to technical formulations and fieldsprayed grains. Recoveries ranged from 91.35 to 100.50% for a ferbam formulation containing 85% active ingredient and from 88.06 to 100.00% for a ziram formulation containing 80% active ingredient. Recoveries from fortified samples were 93.69 to 99.56%.
Tyramine Content of Raspberries and Other Fruit
Authors: Coffin D E
Published: February 2020

The tyramine contents of 14 fruits and 9 fruit jams have been determined by gas chromatography of the trifluoroacetyl derivative of tyramine. Tyramine contents of more than 1 μg/g were found only in raspberries, raspberry jams, and 1 sample of apricot jam. The tyramine content of 15 samples of fresh raspberries varied from 12.8 to 92.5 μg/g; tyramine content of raspberry jams varied from 8.0 to 38.4 μ/g- The levels of tyramine in raspberries in relation to other fruit and the stability of tyramine under processing conditions indicate that it is a useful indicator of the presence of raspberry in fruit products. However, the wide variation in the levels of tyramine in raspberries indicates that it is not a satisfactory criterion for the estimation of the raspberry content of fruit products.
Determination of Small Quantities of Butyric Acid in Fatty Foods Application to Determination of Fatty Material of Butter
Authors: Karleskind A , Valmalle G , Wolff J -P
Published: February 2020

A gas chromatographic method is described for the determination of small quantities of butyric acid in fatty foods. After saponification of the fat in the sample and acid decomposition of the soaps formed, the fatty acids are steam distilled and butyric acid and other volatile acids are collected in dilute NaOH solution. The sodium salts formed are dried and then transformed directly into methyl esters. Methyl butyrate is determined by gas chromatography with an internal standard (methyl valerate).
Separation of Trisulfapyrimidines by Partition Column Chromatography
Authors: Miller Harvey M
Published: February 2020

A column partition method for the separation of the trisulfapyrimidines (sulfamethazine, sulfamerazine, and sulfadiazine) has been developed and studied collaboratively. The sulfas are separated on a O.1N KHCO3 column and eluted with various organic solvents. Three different samples gave fair results with an overall standard deviation of 2.58%. Difficulties were encountered with the 1-butanol used as a solvent and with the Celite. Further work is needed to correct this problem.
Effect of Freeze-Drying and Cooking on Shrimp Quality
Authors: Moorhouse Barbara R , Salwin Harold
Published: February 2020

Approximately 500 pounds of white shrimp were stored in crushed ice until they decomposed. Portions were withdrawn at intervals and processed. Based on judgments of odor, shrimp that reached a stage of incipient decomposition before processing were rated as passable after they were freeze-dried or cooked. The organoleptic quality of samples that reached a stage of advanced decomposition was also improved by processing, but not to the extent of their being classified as passable. Aerobic plate counts increased during storage but they were reduced significantly by freezedrying or cooking. Although there were changes in composition during storage, the classical chemical tests used were of limited value for assessing the degree of decomposition. Also, many volatile decomposition products were lost during processing. Computing the results of chemical analyses on a moisturefree basis offered distinct advantages. Inasmuch as organoleptic, bacteriological, and chemical tests on the finished products failed to reveal the decomposed condition of the starting material, there is need for additional investigation of methods for that purpose.
High Resolution Infrared Spectra of Some Naturally Occurring Sesquiterpene Hydrocarbons. II. Second Series
Authors: Wenninger John A , Yates Ronald L
Published: February 2020

An additional 24 high resolution IR spectra of naturally occurring sesquiterpene hydrocarbons are presented. Compounds were isolated from essential oils and purified by GLC techniques. The purity of each compound was checked by capillary column GLC. Infrared spectra of the following compounds are included: aromadendrene, allo-aromadendrene, cis-α-bergamotene, trans-β-bergamotene, cisa-α-bisabolene, trans-α-bisabolene, “α2-bisabolene“, cis-γ-bisabolene, β-cadinene, β1-cadinene, α-calacorene, chamazulene, β-chamigrene, “cubenene“, α-himachalene, β-himachalene, longicyclene, longifolene, α-muurolene, γ-muurolene, γ-patchoulene, epi-β-santalene, selina-4,ll-diene, and ylangene.
Assessment of the Nutritive Value of Heated Fish Protein Concentrates (FPC) by a Simple In Vitro Pepsin Digestion Procedure
Authors: Knipfel J E , Botting H G , Mclaughlan J M
Published: February 2020

A simple in vitro pepsin digestion procedure with capacity for large numbers of samples has been developed for assessing the nutritive value of FPC in quality control laboratories. In vitro dry matter digestibility (DMD) of autoclaved FPC was significantly correlated with in vivo DMD of the same FPC fed as supplements to wheat gluten diets for rats. Reduced nutritive value caused by autoclaving was not reflected in animal growth until after 4 hr of autoclaving, when the diet contained 4% FPC. Blood plasma and fecal concentrations of lysine and methionine and digestibility data showed that nutritive value of FPC was reduced after shorter periods of autoclaving than was suggested by growth. Reduction of the FPC supplement to 2.5% of diet resulted in nutritive value decreases becoming apparent after shorter autoclaving periods and in the attainment of a significant correlation between in vitro DMD and animal growth criteria.
Quantitative Ultraviolet Determination of Amiben in Dry Granular and Liquid Formulations: Collaborative Study
Authors: Brunstad Joax W
Published: February 2020

Amiben is determined as the sodium salt in 1% NaOH at 297 nm. Prepared materials and technical formulations containing 0-60 μg amiben/ml were analyzed in a collaborative study. Standard deviations for technical samples ranged from 0.05 to 0.45 and for prepared samples from 0.02 to 0.35. The method is recommended for adoption as official first action.
Fluorometric Analysis of Carbaryl Insecticide in Mixed Formulations
Authors: Argauer Robert J
Published: February 2020

The carbaryl present in formulations that contain other pesticides can be readily determined quantitatively by measuring the fluorescence emitted in dilute methanol solution or in an aqueous solution of sodium hydroxide during ultraviolet light excitation. The procedure includes a test that quickly detects and measures the amount of 1-naphthol present.
UV Identification and Quantitative Measurement of Quinaldine Residues in Fish
Authors: Allen John L , Sills Joe B
Published: February 2020

A method for the confirmatory analysis ofquinaldine residue in fish is described. The method utilizes the same extraction and cleanup procedure as the GLC method reported previously. The lower limit of sensitivity for quinaldine residue in fish muscle is 0.01 ppm. Identification is accomplished by comparing the UV spectra of the sample and a standard solution of quinaldine.
Gas-Liquid Chromatographic Method for the Determination of Isomeric Purity of Butylated Hydroxyanisole
Authors: Mahn F P , Viswanathan V , Plinton C , Venturella V S , Senkowski B Z
Published: February 2020

An assay method was investigated for the determination of the ratio of 2- and 3-isomers in butylated hydroxyanisole. The developed procedure involves dilution of the sample with acetone and injection into a gas chromatograph equipped with a hydrogen flame ionization detector. Diphenylamine is a suitable internal standard. XE–60 liquid phase effected an excellent resolution of the 2- and 3-isomers and diphenylamine. The method is quantitative and rapid; the chromatogram is completed in approximately 20 min.
Quantitative and Qualitative GLC Analysis of Free Amino Acids in Fruits and Fruit Juices
Authors: Fernandez-Flores Enriqe , KLINE DAVID A , Johnson Arthur R , Leber Harry L
Published: February 2020

V method utilizing gas-liquid chromatography and the Sorensen formol titration procedure has been devised for the qualitative and quantitative analysis of amino acids in fruits. Korty-four samples representing 22 varieties of fruits were analyzed for 15 free amino acids. The amino acids were determined as N-trifluoroacetyl n-butyl esters. In a majority of the fruits, aspartic acid was the major component, while hvdroxvproline was the minor component when present. All fruits were found to have different quantitative profiles as well as a distinct qualitative distribution of the free amino acids.
Quantitative Aspects of Isothermal and Programmed Temperature Gas Chromatography of Fatty Acid Esters and a Practical Lower Limit of Detection
Authors: Iverson John L
Published: February 2020

This study was initiated to define the importance of temperature and retention volume in quantitative gas chromatography with thermal conductivity detectors (TCD) and flame ionization detectors (FID). Optimum temperature and optimum retention volume increase with molecular weight for the C12 to C28 saturated esters. It is demonstrated that relatively large amounts of very long chain methyl esters would be undetected by present optimum isothermal methods for the usual fatty acids reported. The shape of gas chromatographic peaks is correlated with the linear range of detector response as a basis for a limit of detection. The limit of detection varies logarithmically with molecular weight in isothermal analysis. However, by using optimum programmed temperature gas chromatographic (PTGC) techniques, the limit of detection increases slowly with molecular weight and increased retention volumes.
Improved Quantitative Method for the Determination of Aldicarb and Its Oxidation Products in Plant Materials
Authors: Carey William F , Helrich Kenneth
Published: February 2020

A simplified method has been developed for the quantitative determination of aldicarb and its oxidation products, the sulfoxide and sulfone, in oranges, potatoes, carrots, corn, green beans, and silage. The method involves quantitative extraction from plant matrix, separation of aldicarb, the sulfoxide, and the sulfone on a liquid chromatographic column, oxidation to the sulfone, and GLC determination of the sulfone, using a sulfur mode-flame photometric detector. This method has a limit of detection of 0.005 ppm, using a 150 g sample for analysis. Recovery studies were run on a number of crops and silage. Samples of potatoes from Tern ik-trea ted plots were also analyzed.
Determination of Vitamin E in Foods and Feeds—A Collaborative Study
Authors: Ames Stanley R
Published: February 2020

A collaborative study was conducted to evaluate a method for the determination of vitamin E in foods and feeds. Both the naturally occurring and the supplemental vitamin E are extracted from the sample by the appropriate procedure, the lipid residue is saponified, and α-tocopherol is isolated by TLC and determined colorimetrically. To determine supplemental a-tocopheryl acetate specifically, the sample is extracted by the appropriate procedure, reducing substances including natural atocopherol are removed by oxidative chromatography, the a-tocopheryl acetate is saponified, and the resulting a-tocopherol is determined colorimetrically. These assays for vitamin E in foods and feeds are neither rapid nor easy and considerable skill is required to obtain reliable results. Data reported by 7 collaborators on 7 samples indicate that the standard deviation among laboratories is not significant for the determination of total α-tocopherol but is significant for the determination of supplemental a-tocopheryl acetate. The weighted mean coefficients of variation were 11.0% for the determination of total a-tocopherol and 7.0% for the determination of supplemental a-tocopheryl acetate. Since an official procedure for the determination of vitamin E in foods and feeds is needed and since most laboratories were successful in carrying out the procedure, the Associate Referee recommends that the method as modified be adopted as official first action.
Incidence of Clostridium perfringens in Dehydrated Soup, Gravy, and Spaghetti Mixes
Authors: Keoseyan Susan Adelle
Published: February 2020

Clostridium perfringens was found in 14% of a total of 250 analytical units of dehydrated mixes of soup, gravy, and spaghetti. The incidence in these products was as follows: spaghetti 40%, gravy 10%, and soup 5%. Presence of C. perfringens at relatively high levels may be of epidemiological significance because of short cooking time for rehydrated mixes and mishandling of prepared mixes.
Tylosin Residue Analyses in Swine Tissue
Authors: Kline R M , Waitt W P
Published: February 2020

A tolerance of 0.2 ppm, which is less than the sensitivity of the analytical method in certain swine tissue, was established for tylosin in edible animal tissues. Extrapolation of tissue residue data at high feeding levels indicates that the negligible residue level would not be exceeded from feeding tylosin at 100 g/ton, the recommended dosage for swine. Residual tylosin was detected in liver tissue from swine receiving tylosin at 1000 g/ton at 0 hr withdrawal, but no residues above the tolerance were detected in tissues when tylosin was fed at 500, 200, and 100 g/ton.
Microbiological Assay of Streptomycin in Feeds
Authors: Mayernik John J , Fiori Gloria Y
Published: February 2020

The official AOAC first action non-sulfadiazine-sensitized method for the determination of streptomycin in feed was modified slightly. The modification consists of filtering the assay solution to remove the precipitate which forms when the solution is adjusted to pH 8. Eighteen collaborators used this modified method to assay 12 poultry and swine feeds containing 30-5000 g streptomycin/ton. Mean recoveries ranged from 97.6 to 104.0% and coefficients of variation ranged from 4.0 to 7.1%. It is recommended that approval of the non-sensitized method, as modified, be extended to 30 g/ton from the previously adopted level of 5600 g/ton.
6,6′-Oxybis(2-Naphthalenesulfonic Acid) in Schaeffer’s Salt
Authors: Marmion Daniel M , White Robert G , Cashion Francis W , Whitcomb B Bailey
Published: February 2020

An unknown present in Schaeffer’s salt is identified as 6,6′-oxybis (2-naphthalenesulfonic acid), DONS. A method is presented for the determination of DONS in commercial Schaeffer’s salt by column chromatography and UV spectrophotometry.
Automated Steam Distillation and Fluorometry for Screening for Carbaryl as 1-Naphthol in Fruits and Vegetables
Authors: Ott Daniel E , Ittig Monika , Friestad Håkon O
Published: February 2020

A rapid method for screening for carbaryl in methylene chloride extract solutions of various fruits and vegetables has been developed. For most crops, sufficient cleanup was effected by solidification of many impurities in paraffin wax and further by automated steam distillation of 1-naphthol (free or free plus that produced from carbaryl by alkaline hydrolysis) into an alkaline scrubbing solution. This solution was pumped automatically into a fluorometer equipped with a continuous flow cell and a strip chart recorder to monitor the fluorescence intensity of 1-naphthol present. Apples and carrots required an additional cleanup procedure prior to presentation to the automated steam distillation and fluorometer system. Of 20 crops tested, celery was the only one causing background interference even after use of the additional cleanup procedure. All of the other crops were rapidly screened for carbaryl plus 1-naphthol or for free 1-naphthol, depending upon the sample preparation procedure; the difference between the 2 assays represents the contribution from the carbaryl residue. The automated analytical system was operated at a rate of 20 samples/hr and the lower limit of detection for carbaryl was 0.2 ppm of the fortified crop.
UV Spectrophotometric Assay of Neostigmine Methylsulfate as the Alkaline Hydrolysis Product, 3-Dimethylaminophenol
Authors: Kling Rita E
Published: February 2020

A rapid and sensitive method for the assay of neostigmine methylsulfate (NMS) in injectables has been developed. Following extraction of phenol and paraben preservatives, NMS is hydrolyzed to 3-dimethylaminophenol, which is determined by ultraviolet spectrophotometry. Standard recoveries of NMS from simulated injection solutions containing either (1) no preservatives, (2) phenol, or (3) parabens averaged 99.8%. A collaborative study was conducted using 2 simulated injection solutions (one without preservatives, one containing parabens) and 2 commercial injectables (one containing phenol, one containing parabens). Results of 9 collaborators averaged 100.6±1.4 and 102.1±1.5% for the simulated solutions. Results for the 2 commercial preparations averaged 103.0±1.2 and 101.8±1.6% of the respective label declarations. The results of the proposed method are in good agreement with the USP XVII and the new USP XVIII methods. The method is recommended for adoption as official first action.
The Loss of Food Flavors from Laboratory Animal Diets. II. Effect of Laboratory Environment
Authors: Jones William I , Roback Loretta A , Taylor Jean M
Published: February 2020

Analyses of animal diets containing flavoring agents or related substances were made after mixing and at 7 days to determine if there was a decrease in concentration on exposure to the laboratory environment. The test compounds were extracted from the diets by steam distillation or alcoholic extraction and the concentration was determined by saponification or measurement of UV absorbance. The amount of loss was inversely related to the boiling point for most compounds with the low-boiling ester, allyl butyrate, showing the greatest loss, 72%. Most compounds with boiling points greater than 220°C showed less than 10% loss.
Determination of Low Level Isolated Trans Isomers in Vegetable Oils and Derived Methyl Esters by Differential Infrared Spectrophotometry
Authors: Huang Anita , Firestone David
Published: February 2020

A procedure is described for differential infrared spectrophotometric determination of low levels (1–6%) of isolated trans isomers in vegetable oils or derived methyl esters. Triglycerides and methyl esters of known isolated trans content were analyzed by the procedure and results compared with those obtained with the American Oil Chemists’ Society tentative method for isolated trans isomers. Results obtained by the described method are more accurate than those obtained by the AOCS method.
Determination of Alcohol-Insoluble Solids in Frozen Peas
Authors: Winter F H
Published: February 2020

Additional collaborative studies on the method proposed were conducted. The standard deviation for 11 collaborators was 0.026 for frozen peas averaging 15.08% AIS and 0.30 for frozen peas averaging 19.74% AIS. It is recommended that the method be adopted as official first action.
Collaborative Study of the Colorimetric Determination of Nifursol in Feeds
Authors: Zietlow David C , Morrison J L
Published: February 2020

A collaborative study of a method for nifursol in feeds bas been conducted. The drug is extracted from the feed with DMF. Most of the extracted interferences are removed from the DMF solution by chromatographing the sample through an alumina column; the nifursol is then reacted with phenylhydrazine to form the 5-nitrofurfural phenylhydrazone, which is extracted into toluene and determined spectrophotometrically at 555 nm immediately after the addition of Hyamine-OH. The average recovery of all samples from 10 collaborators was 101.4%, with an average coefficient of variation of 7.88%. The method is recommended for adoption as official first action.
Chromatograms of Foods for Multicomponent Residue Determination of Pesticides Containing Phosphorus and/or Sulfur by GLC with Flame Photometric Detection
Authors: Bowman M C , Beroza Morton , Hill K R
Published: February 2020

As part of an effort to devise a multicomponent pesticide residue analysis, temperature programmed gas chromatography with the Melpar flame photometric detector was used to obtain chromatograms of extracts of 39 repsentative foods on the thermally stable OV-101 and OV-210 packings. The chromatograms, which show where interference occurs with each food, supplement data previously reported on the retention times of 138 pesticides and metabolites containing phosphorus and sulfur in their molecules. Thus, where interferences from a food are absent, observation of pesticide peaks is possible. Food samples were extracted by one of 4 methods and then partitioned between hexane and acetonitrile by one of 2 procedures prior to analysis by gas chromatography. Very little interference was seen in the chromatograms of about 90% of the food extracts in the P mode and about two-thirds of the food extracts in the S mode; except for high fat samples, weights of co-extractives were also generally small. The lower limit of detection for most pesticides was estimated to be 0.01–0.05 ppm in the P mode and 0.02–0.1 ppm in the S mode. Analysis using the S mode has limited applicability because of the large samples needed to offset the lesser sensitivity of the S detector and the resulting contamination of the chromatographic column by coextractives. Analysis using the P mode is considered practical now. Retention time data on 8 additional pesticidal compounds are also reported.
A General Method for Organophosphorus Pesticide Residues in Nonfatty Foods
Authors: Storherr R W , Ott P , Watts R R
Published: February 2020

A method is presented for determining residues of organophosphorus pesticides and alteration products in nonfatty foods. This method employs the acetonitrile extraction procedure as used by FDA for the chlorinated hydrocarbon pesticides. Cleanup is performed with a short charcoal column. GLC, using the potassium chloride thermionic detector or flame photometric detector, is used for determination. Forty-one organophosphorus pesticides and/or alteration products are evaluated.
GLC Determination of Methanol in Liquids: Collaborative Study
Authors: Andersen Donald L
Published: February 2020

A rapid, specific method for methanol in aqueous and nonaqueous liquids has been developed and studied collaboratively. The method involves sample dilution with dioxane to approximately 0.4% methanol and injection into a gas chromatograph fitted with a Porapak R column and a flame ionization detector. A collaborative study, with 7 collaborators each reporting on 6 test portions, showed coefficients of variation of 2.7, 2.1, 2.3, 4.2, 1.8, and 3.5. The method has been adopted as official first action.
Detection of Wheat Grains Contaminated with Urine
Authors: Thrasher J J
Published: February 2020

A modification of the present official method, 40.131-40.132 (Official Methods of Analysis, 11th Ed.), for the detection of urea is presented. Collaborative results show the modification of incorporating the urease and bromothymol blue in a soft (1%) agar to he more sensitive and responsive to the presence of urine on grains and seeds than the official method. The modified method has been adopted as official first action.
Collaborative Study of the Use of a Convenient Salt Measuring Titrator for Monitoring Salt Concentration in Meat, Fish, and Cheese
Authors: Vander Were Loren J , Free Alfred H
Published: February 2020

A collaborative study has been made on the use of the QUANTAB Chloride Titrator for monitoring salt concentration in meat, fish, and cheese. Data from 12 collaborators on 6 samples show good agreement of results from all of the collaborators on all of the samples. The QUANTAB method has been adopted as a procedure.
Automated Colorimetric Determination of Phenylephrine Hydrochloride in Drug Formulations. I. Development of the Method
Authors: Lane Jonathan R
Published: February 2020

The Emerson colorimetric reaction as modified by Koshy and Mitchner was adapted for automation of the phenylephrine assay. Using the AutoAnalyzer, studies were made of different reagent concentrations and reagent volume ratios to satisfy the reaction conditions of the official final action method, 36.112-36.114. The debubbler-flowcell design was changed to improve the flow dynamics, and the internal volumes of all unsegmented flow lines were minimized to permit good resolution at fast sampling ratios (50/hr). Relative standard deviations of less than 0.5% were obtained on multiple determinations of the same solutions. Essentially 100% recovery was obtained on assays of phenylephrine HCl added to a composite nasal solution preparation.
Collaborative Study of the Automated Method for K2O in Fertilizers
Authors: Hambleton Larry G
Published: February 2020

The automated method for K2O in fertilizers was studied again this year. The results from the automated method are compared to those obtained by the official STPB method, 2.090, for 10 typical fertilizer samples and a potassium nitrate primary standard. Nine complete sets of data are evaluated by the technique of closely matched pairs. The data show no difference between the different models of flame photometers. The means and standard deviations from the automated method compare favorably to those received with the official STPB method. The automated method for K2O in fertilizers has been adopted official first action.
Collaborative Study of a Gas Chromatographic Method for the Analysis of Atrazine
Authors: Murphy R T , Hofberg A H , Buser H R
Published: February 2020

A gas chromatographic method for the determination of atrazine in wettable powder formulations containing about 80% active ingredient was collaboratively studied, using the matched pair scheme. The atrazine was extracted from the powder with chloroform containing dieldrin as an internal standard and chromatographed on Carbowax 20M, using a flame ionization detector. Determinations on the 2 samples by 13 collaborators using peak height measurements show an overall coefficient of variation of 1.0% and a coefficient of variation of random error of 1.2%. Statistical evaluation of these factors reveals no evidence of systematic error contribution. The method has been adopted as official first action.
Collaborative Study of a Gas Chromatographic Method for the Analysis of Prometryne
Authors: Murphy R T , Hofberg A H , Buser H R
Published: February 2020

A gas chromatographic method for the determination of prometryne in wettable powder formulations containing about 80% active ingredient was collaboratively studied, using a matched pair scheme. The prometryne was extracted from the powder with chloroform containing dieldrin as an internal standard and chromatographed on Carbowax 20M, using a flame ionization detector. Determinations on the 2 samples by 12 collaborators using peak height measurements show an overall coefficient of variation of 1.4%, coefficient of variation of random error of 1.3%, and for systematic error, 0.4%. Application of the F-test shows the systematic error not to be significant. The method has been adopted as official first action.
Collaborative Study of a Method for the Determination of Trimethylamine Nitrogen in Fish
Authors: Boland Frederick E , Paige Dorothy D
Published: February 2020

Dyer’s method for the determination of trimethylamine was collaboratively studied. Six samples of fish extract and one standard solution were sent to each of 9 collaborators. The results from one laboratory differed significantly from the remainder and were not included in the statistical analysis. The results from the remainder of the collaborators were generally in good agreement. Results clearly differentiate between the acceptable and decomposed samples which were used in this study. The method for determining trimethylamine nitrogen in fish has been adopted as official first action.
Rapid Determination of Mercury in Fish
Authors: Bache Carl A , McKone Colin , Lisk Donald J
Published: February 2020

Successful oxygen flask combustion of samples of high oil or fat content has been particularly difficult in the past. A method is described for analysis of mercury in fish by modified Schöniger combustion and colorimetric determination of mercuric dithizonate. The recovery of mercury added to fish at the 0.5 ppm level was satisfactory.
IR Detection of False Positives for Gums in Mayonnaise Due to Mustard Flour
Authors: Krinitz Benjamin
Published: February 2020

A number of samples of mayonnaise were examined for added gums by first the precipitation of the protein with trichloroacetic acid and then the alcohol precipitation of water-soluble “gum.” Although the hydrolyzed precipitate gave a positive copper reduction and Molisch test, positive identification of gum could not be made. The IR spectrum confirmed the fact that the false positive for gums was due to the presence of mustard flour in the mayonnaise.