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The field desorption mass spectra of several underivatized cyanogenic glycosides exhibit molecular ions or ions derived from the parent compound by protonation and alkali metal cationization. Abundant fragment ions are present and can be readily related to structure. Significant deviations from established fragmentation pathways are observed due to the nature of the aglycone. The ability to successfully determine the presence of cyanogenic glycosides by field desorption is demonstrated in crude extracts isolated from Vicia sativa, a food-contaminating plant material.

For many years it has been known that plants, when subjected to stress, produce "unusual" metabolites in response to that stress. Some of these metabolites are toxic and, consequently are of concern from the standpoint of contamination of foods. Each year additional stress metabolites are isolated and identified from plants and plant products subjected to stress conditions; these conditions include infection of the plant by microorganisms, mechanical damage during processing or storage, exposure to temperature extremes and the like. The need for an intensive research effort into formation, isolation and characterization, and toxicological evaluation of such metabolites in plants used for human food is discussed.

A sample preparation method has been developed that provides a nitric acid-hydrogen peroxide digestion of plant tissue when it is heated internally by the oscillating electromagnetic field generated in a microwave oven. The total elemental concentration for barium, calcium, magnesium, manganese, phosphorus, potassium, sodium, sulfur, and zinc can be determined by inductively coupled argon plasma emission spectroscopy after sample preparation in a microwave oven. The method is rapid and provides quantitative results that agree with certified values for 4 National Bureau of Standards Standard Reference Materials: 1570 Spinach, 1572 Citrus Leaves, 1573 Tomato Leaves, and 1575 Pine Needles.

In a review presented at the first FAO/WHO/UNEP Conference on Mycotoxins in 1977, the occurrence of aflatoxins, zearalenone, ochratoxin A, citrinin, trichothecenes, patulin, penicillic acid, and the ergot alkaloids was indicated to be significant in naturally contaminated foods and feeds. The information presented on aflatoxin contamination greatly exceeded that for all other mycotoxins combined. This study reviews the worldwide levels and occurrence of mycotoxins in various commodities since 1976. Comparatively few countries have lowered the acceptable levels for aflatoxins in susceptible commodities. However, intensified efforts are needed to establish control of aflatoxin levels in the global food supply, particularly in peanuts, tree nuts, corn, and animal feeds. Extensive deoxynivalenol (DON) contamination of grains, especially wheat, was demonstrated. Co-contamination of grains by Fusarium toxins, especially DON and nivalenol, with zearalenone to a lesser extent, was reported. However, more information on co-occurrence of Fusarium toxins in cereals should be developed. When contamination of feeds by ochratoxin A was significant, this toxin occurred in swine kidney and smoked meats in high levels. On the basis of occurrence and/or toxicity, patulin and penicillic acid contamination of foods does not appear to be of real concern. More recent developments suggest, however, that expanded monitoring studies of Alternaria toxins, moniliformin, citrinin, cyclopiazonic acid, penitrem A, and ergot alkaloids are indicated.

Aflatoxins, metabolic products of the molds Aspergillus flams and A. parasiticus, may occur in foods and feeds. These toxins cannot be entirely avoided or eliminated from foods or feeds by current agronomic and manufacturing processes and are considered unavoidable contaminants. To limit aflatoxin exposure, the U.S. Food and Drug Administration (FDA) has set action levels for these toxins in foods and feeds involved in interstate commerce. FDA continually monitors food and feed industries through compliance programs. This report summarizes data generated from compliance programs on aflatoxins for the fiscal year 1986. Commodities sampled included peanuts and peanut products, corn and corn products, tree nuts, cottonseed, milk, spices, manufactured products, and miscellaneous foods and feeds. Correlations were highest between aflatoxin contamination and geographical areas for corn/corn products and cottonseed/cottonseed meal. Higher incidences of aflatoxin contamination in corn and corn products designated for human consumption were observed in samples collected in the southeastern states (32 and 28%, respectively). A higher incidence of contamination was observed in corn designated for animal feed from Arkansas-Texas (74%) than from the southeastern states (47%). Only 3% of feed corn from corn belt states contained detectable aflatoxins. All aflatoxin-contaminated cottonseed was collected in the Arizona-California area; 80% of cottonseed meal analyzed from this area also contained detectable levels of aflatoxins. No aflatoxin Mi was detected in any of the 182 samples of fluid milk and milk products examined. The percentage of samples that contain measurable levels of aflatoxins is expected to vary with commodities from year to year; thus, the 1986 information can be used as a baseline for comparison to determine the effectiveness of control efforts exerted by the food and feed industries.

Chemical changes that occur in the proteins, nucleotides, and lipids of fish tissue during storage at low temperatures were investigated. Homogenized tissue, prepared from fresh rock-fish (striped hass, Roccus species), was stored up to six days at temperatures from -10° to 4°C and then analyzed. At 0°C and below, the solubility of myofibrillar proteins decreased. There were also changes in polyacrylamide gel electrophoretic patterns of protein extracts. The total nucleotide content decreased rapidly at all temperatures. The lipids were extracted from each sample and separated into neutral lipids, phospholipids, and free fatty acids by column chromatography. The fatty acid composition of each fraction was determined by gas chromatography. In the fresh tissue, polyunsaturated acids occurred in greatest proportion in the free fatty acid and phospholipid fractions, whereas inono-unsaturated acids were inofe highly concentrated in the neutral lipids. The percentages of saturated acids were approximately the same in all fractions. During storage, there were considerably larger losses of individual acids from phospholipids than from neutral lipids. The polyunsaturated acids of the phospholipid fraction were affected most. Over 10% of these aeids were lost in six days at ice temperature, but only a small proportion of the losses was accounted for by increases in free fatty acids. Oxidative proo esses may account for the imbalance because the rate of oxidation, as measured by the thio-barbituric acid test, increased with storage temperature in the same manner as the rale at which unsaturated fatty acids were lost from the pliospliolipuls. Losses of polyunsaturated acids from the neutral lipids were much smaller, suggesting a selectively protective mechanism or environment in that fraction. The changes in the phospholipid fatty acids may provide the basis for useful objective tests of fish lecomposilion.

The stability of fish lipids during storage of fish tissue at ice temperature was investigated. Homogenized tissue from rockfish (striped bass, Roccus species) was stored 16 days at melting ice temperature. Lipids were extracted at intervals and separated into various components by silicic acid column chromatography. Changes in the weights of individual lipid components were correlated with gas chromatographic data on changes in individual acids of these components. In the fresh tissue, the phospholipid fraction contained the highest proportion of polyunsaturated acids and the neutral lipid fraction contained the highest proportion of monounsaturated acids. During storage of the tissue, there were decreases in the weights of total phospholipids and neutral lipids and an almost equivalent increase in the amount of free fatty acids. Although there were changes in all acids during storage, the polyunsaturated acids, eicosapentaenoic (C20:5) and docosahexaenoic (C22:6), were affected most and were lost at a faster rate from phospholipids than from neutral lipids. The loss of polyunsaturated acids was apparently by a selective process because most of the loss was from the cephalin fraction, even though it contained only about ¼ of the total polyunsaturated acids. Relatively small amounts of these acids were lost from the neutral lipids and virtually none from the lecithin.

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 >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.

In a 1979 survey of manufactured dairy products (992 samples of nonfat dry milk, vanilla ice cream, yogurt, Cheddar cheese, and cottage cheese) for aflatoxin M 1 contamination, one sample, a cottage cheese, had detectable aflatoxin equivalent to .08ng/ml in the milk from which the product was made. Samples were taken by Food and Drug District inspectors from randomly selected establishments at three times throughout the year. The distribution of sample quotas to each District was weighted to double the representation of establishments in the southern tier of states. The conclusion from this survey is that in a "normal" year aflatoxin M 1 should not be in a manufactured dairy product in the United States at a level in excess of that from milk with .1ng aflatoxin M 1 /ml.

The production of phytoalexins by various plants belonging to the family Leguminosae is reviewed. Many of the plants involved and/ or products derived from them are currently being consumed by humans. Most of the compounds that have been characterized were found to be toxic to certain microorganisms and hence they may be potential hazards for humans. The induction, chemical and physical characteristics, and other available information on these compounds are presented along with pertinent references. The lack of complete information on many of the phytoalexins reported suggests the need for further and continuing research in this area.

Copy of an article from the Gospel Messenger, April 1, 1956 issue, written from the perspective of a participant, Garnett E. Phibbs, pastor of the Champaign church, Illinois, at the Summer School of Alcohol Studies from a religious point of view. Lists accusations against the school. Calls for appreciation of the Yale pioneers.

Alexander, Aaron D. (Walter Reed Army Institute of Research, Washington, D.C.), Herbert G. Stoenner, Garnett E. Wood, and Robert J. Byrne . A new pathogenic Leptospira , not readily cultivated. J. Bacteriol. 83: 754–760. 1962.—A pathogenic Leptospira was isolated from water of the Grand River, (S.D.) that differed significantly from other known leptospirae in that it could not be cultivated in conventional leptospiral media. Growth was promoted in Fletcher's medium modified to contain 20% rabbit serum. The isolate, after several serial passages, was lethal for hamsters. It could not be adapted to grow in the chick embryo. Guinea pigs and calves inoculated with the isolate developed febrile and antibody responses but showed no other overt signs of disease. The strain was identified on the basis of cross-agglutination and agglutinin-adsorption tests as a new subserotype of Leptospira naam and was therefore designated as L. naam , subserotype dakotii .

In this thesis I examine scientific practices which produce data on air pollution, and the ways in which these data are managed and co-ordinated by researchers to make claims about air pollution. In doing so, I attend to the everyday practices and experiences of scientific research, exploring the ways in which science is a social and cultural endeavour. Based on three years ethnographic fieldwork with a multi-disciplinary project studying the relationship between Weather, Health and Air Pollution (WHAP), I trace the local meaning of research, but also its implications, as part of a wider ensemble of environmental health and policy relations.\ud Managing different data and co-ordinating research practices was understood by scientists as a fundamental part of doing ‘collaborative research’. Collaboration was performed through the movement of data, and also became an ethnographic device by which I traced and followed the activities of scientists. Working with data was considered ‘real’ scientific work, and it was this appeal to authenticity that led me to examine data as a form of material practice. The craftwork involved in the production and use of data illustrates the embodied and tacit nature of research. The way in which these different types of knowledge were negotiated by researchers shows that ‘objectivity’ is situated, and that scientific legitimacy is contingent on the social and technical configuration of tools, technologies, people and standards.\ud Drawing upon research from social and cultural studies of science, I emphasise both the representational and performative shape of science. The reciprocal nature of data practices configure and enact accepted ways of seeing air pollution which make scientific claims appear as ‘natural’ and logical. These not only represent air pollution but mobilise policy norms and modes of intervening, and therefore particular ideas, values and power dynamics. The chapters in this thesis explore the collection, production, processing and re-use of multiple air pollution data, and how the relations - of technologies, people and ideas - imbricated in data mobilise air pollution as an environmental health concern.