P-FLUX: A phosphorus budget dataset spanning diverse agricultural production systems in the United States and Canada.

Quantifying spatial and temporal fluxes of phosphorus (P) within and among agricultural production systems is critical for sustaining agricultural production while minimizing environmental impacts. To better understand P fluxes in agricultural landscapes, P-FLUX, a detailed and harmonized dataset of P inputs, outputs, and budgets, as well as estimated uncertainties for each P flux and budget, was developed. Data were collected from 24 research sites and 61 production systems through the Long-term Agroecosystem Research (LTAR) network and partner organizations spanning 22 U.S. states and 2 Canadian provinces. The objectives of this paper are to (a) present and provide a description of the P-FLUX dataset, (b) provide summary analyses of the agricultural production systems included in the dataset and the variability in P inputs and outputs across systems, and (c) provide details for accessing the dataset, dataset limitations, and an example of future use. P-FLUX includes information on select site characteristics (area, soil series), crop rotation, P inputs (P application rate, source, timing, placement, P in irrigation water, atmospheric deposition), P outputs (crop removal, hydrologic losses), P budgets (agronomic budget, overall budget), uncertainties associated with each flux and budget, and data sources. Phosphorus fluxes and budgets vary across agricultural production systems and are useful resources to improve P use efficiency and develop management strategies to mitigate environmental impacts of agricultural systems. P-FLUX is available for download through the USDA Ag Data Commons (https://doi.org/10.15482/USDA.ADC/1523365).

[Environmental medicine group diagnosis of children--studies from 1982 to 1990. Review]. / Umweltmedizinische gruppendiagnostische Kinder-untersuchungen 1982-1990. Ubersicht.

In the period of 1982-1990 a total of 5760 children (2893 boys, 2816 girls) were examined in the frame-work of the Clean Air Programme Rhine-Main: from the polluted Rhine-Main area 2511 children (Wiesbaden 1682, Frankfurt since 1985, 825), from the control areas 3153 children (Freiburg area 1937, Starnberg area 1316). Healthy children living in the industrialised Rhine-Main area exhibited alterations of the following parameters compared with healthy children living in the less polluted control areas: Long-term alterations, enlarged and fissured, rough palatine tonsils, palpably enlarged cervical and mandibular lymph nodes, Short-term alterations, erythrocyte count: from 1981-1988 relatively smaller numbers, from 1988-1990 equalized to the scatter range of controls, hemoglobin values: corresponding to erythrocyte counts, activity of lymphocyte nucleoli: increased until 1985, later on equalized, lymphocyte count: reduced, T8-suppressor cell count: decreased, chemiluminescence of granulocytes: increased, palatine tonsils: altered microbial contamination with contact germs, altered physiological resident flora, heavy metals (Pb, Cd) in hair: from 1982-1990 increased, then slowly reduced corresponding to the results of the ambient air analyses. These findings indicate an increased inclination for reaction of the healthy juvenile organism in the sense of biological adaptation to long-term stress, i.e. living for years in an area with air pollution, and are also in good agreement with the measuring values characterising the ambient air quality.

[Water disinfection of dental treatment units using ozone]. / Wasserdesinfektion zahnärztlicher Behandlungseinheiten durch Ozon.

The disinfecting effect of ozonized water has been investigated. Under the precondition that the dental chair had been thoroughly sanitized, the system showed a good disinfecting effect. Finally, for reasons of practical medical treatment, the ozone concentration in air and, for reasons of hygiene in drinking water, the ozone concentrations in water were determined under various conditions. In addition, the influence of continuous-flow water heaters is discussed. The problem of continuous-flow water heaters regarding their effects on the colonisation of water by microbes proves not to be significant. The exposure of patients to disinfectants is discussed.

Cytotoxicity and carcinogenicity of chrysotile fibres from asbestos-cement products.

Fibres from weathered asbestos-cement products have little or no haemolytic activity, as compared with UICC chrysotile; this is probably the result of magnesium leaching during the weathering process. Weathered samples of asbestos cement are cytotoxic, but the release of lactic dehydrogenase (LDH) by guinea-pig alveolar macrophages caused by low and intermediate dust concentrations of UICC chrysotile is greater than that of such samples. The influence of serum is different as between UICC chrysotile and asbestos cement. In the former, LDH release by macrophages is enhanced, whereas it is reduced in the latter. Cytotoxicity is length-dependent in respect of LDH release from macrophages and proliferating cells, as well as cell proliferation. In all test systems, the sample from the unweathered core of an asbestos-cement plate is less toxic; only in the haemolysis system using an unbuffered solution can erythrocyte destruction be observed. This may be because this sample contains fewer single fibres than the others and because the specific surface of those fibres is smaller. The carcinogenicity of the weathered asbestos-cement chrysotile fibres is comparable to that of standard chrysotile fibres following intraperitoneal (i.p.) application.

[Risk detection and risk assessment in environmental hygiene/ environmental medicine]. / Risikoerkennung und Risikoabschätzung in der Umwelthygiene/Umweltmedizin.

The complex, multifactorial impact of environmental factors on the human being is discussed. The concepts risk detection and risk assessment in environmental hygiene/environmental medicine are defined. For risk detection the special suitability of animal experiments (in vivo tests) as a screening method for the rapid detection of the toxic and oncogenic effects of environmental pollutants are pointed out as well as their supportive role for elucidation of clinical and epidemiological problems and the detection of causal relationships. Beyond that the advantages and disadvantages of the cell culture (in vitro test) are presented and examples of correlations between in vitro and in vivo results are described. For risk assessment, environmental factors, the interior environment as well as problems prospective and retrospective epidemiology are discussed. Finally, the possibilities of the risk assessment are presented and in this connection the determination of geomedically relevant data in order to provide active, effective environmental protection for the exposed population.

[Strategy of environmental medical research]. / Strategie der umweltmedizinischen Untersuchungen.

A report is made on the strategy and tactics of an environmental medical, group-diagnostic study of children which was carried out by order of the Hessian Minister of Social Security within the framework of the Lufreinhalteplan (Clean Air Plan) Rhine/Main in the time from 1982 to 1986. This is a group-diagnostic examination of ten-year-old healthy children in the burdened area Rhine/Main (Wiesbaden, Frankfurt) and in the control areas of Freiburg and Starnberg. The objective of the study is to register the influence of the environment, in particular of air pollution, on a portion of the child population, especially with regard to persons at risk who react particularly sensitive to environmental influences and/or who have special health problems. In this connection it is attempted to convert the measuring data collected for characterizing the environment (ambient air) into effect-oriented data. The targets examined, i.e. anthropometric and clinical examinations as well as microbiological, immunologic and haematologic tests and the analysis of hair are to be evaluated in addition to family and social factors. Beyond that the attempt is made to correlate the results of the study with the biometeorological effective variables.

[Clinical research]. / Klinische Untersuchung.

Distinct differences were determined during the clinical examinations of the ten-year-old child population in the polluted area Rhine/Main (Wiesbaden/Frankfurt) and the control areas Freiburg and Starnberg. In the group with long-term exposure enlarged tonsils with a rough surface, enlarged lymphatic nodes in throat and mandible were frequently found. When determining body height and weight, no distinct differences between the individual areas under examination could be proved.

[Hematology]. / Hämatologie.

The results of the hematologic examinations of children from the polluted Rhine/Main area and the control areas Freiburg and Starnberg are presented. In the years 1982 to 1985, the exposed children show et a lowered number of erythrocytes and a decreased content of haemoglobin as compared to the children from the control areas; this is a sign of permanent stress. When comparing the children from the control area Freiburg, a slight increase in the number of erythrocytes and the haemoglobin content was detected with increasing height as an adaptive reaction.

[Activity of the lymphocyte nucleoli]. / Aktivität der Lymphocytennucleoli.

The results of the lymphocyte-nucleolar test in 1985 and 1986 yielded distinct differences between the exposed children (Wiesbaden, Frankfurt) and the children in the control areas (Freiburg, Starnberg, i.e. an increased number of compact, activated lymphocyte-nucleoli in the former. These results are in harmony with the clinically determined findings on enlarged and fissured tonsils as well as enlarged mandibular and cervical lymph glands as an expression of heightened reactivity of the lymphatic tissue to a long-term burden by environmental factors such as e.g. air pollution.

Epidemiological investigations of decreased employees of the asbestos cement industry in the Federal Republic of Germany.

An epidemiological study of the causes of death was performed covering the entire German asbestos cement industry (10 plants). Of 376 workers who had died in the period of 1 January 1976 - 31 December 1980 and who had been employed for a minimum of 10 years, 314 were included; 307 of these were men. Special consideration was given to the asbestos-related diseases asbestosis, asbestosis in combination with lung cancer, and mesothelioma of the pleura or peritoneum. The relationship between lung cancer with asbestosis and lung cancer without asbestosis is nearly 1:1. From this the conclusion can be drawn that a causal relationship between asbestos exposure and lung cancer can be assumed in only half of the lung cancer cases. This is, however, an upper approximation, since 15 cases of lung cancer were found which is 1/3 less than the expected number in comparison with the normal population. This documents the relatively small excess (SPMR = 1.2) of all cases of lung cancer detected in the asbestos cement industry as compared to the expected lung cancer cases not due to asbestos.

Macrophage functions after exposure to nonfibrous mineral dusts.

The effects of the standard dusts, electrocorundum, and Dorentruper quartz (DQ12), as well as mine dusts have been tested in guinea pig lung macrophage cultures. The parameters compared were: release of lactic dehydrogenase for demonstration of plasma membrane permeability and production of lactic acid as an indicator of carbohydrate metabolism. In addition to the dose-dependent toxicity of different mine, coal and other mineral dusts, we studied the influence of cell culture media and the supplement of fetal calf serum (FCS) and bovine serum albumin (BSA) upon the cell toxicity in this test system. We demonstrated a protective effect of FCS and BSA on dusts of low and medium toxicity, while dusts of high toxicity, like DQ12, were not influenced in their toxicity.

Influence of well-defined mineral fibers on proliferating cells.

The effects of well-defined asbestos and man-made mineral fibers, as well as glass and synthetic fluoroamphibole, on phagocytizing permanent rat tumor cells were tested. The following parameters were compared: cell proliferation as determined by cell count and 3H-thymidine incorporation, RNA synthesis by 3H-uridine uptake, protein synthesis by incorporation of 3H-labeled amino acids, protein content and plasma membrane permeability by release of lactic dehydrogenase. The dosage of most of the dusts was estimated gravimetrically, but for some dusts also numerically. Because of the wide range of different fibers lengths, diameters and specific weights, it was sometimes difficult to compare chemically and physically differing fiber fractions with the same fiber counts. In some cases, resulting weights are so different that a direct comparison of the conclusions is impossible. The results with fibers of diverse sources showed the same trends: the toxicity of fibers increases with increasing length and dose. In this test system we found an inhibition of DNA and RNA synthesis. Protein synthesis as measured by amino acid uptake per total cell culture decreased, but the protein content of the single cell increased as determined by the Lowry method. The increase of plasma membrane permeability as determined by lactic dehydrogenase was also dependent on fiber length and concentration. Generally the thinner the fiber, the greater the toxicity when gravimetrical dosage and the same length distributions are employed. Beyond that we can state that the toxicity of fibers from different sources with similar fiber dimensions is similar. One of the glass fiber fractions has a comparable geometry (length, diameter) to the UICC fraction of chrysotile and exhibits the same high toxicity.

Macrophage functions after exposure to mineral fibers.

UICC, other well-defined asbestos samples and different man-made mineral fibers (MMM) such as glass fiber and synthetic amphibole asbestos were studied in vitro by using rat and guinea pig lung macrophages. These samples had relatively narrow length and diameter spectra. Most of the fiber samples were added to the cultures on a gravimetric basis, although some were added on a numerical basis. Electrocorundum and DQ12 (Dorentruper Quartz) were used as controls at comparable gravimetrical concentrations. The assays used were the release of lactate dehydrogenase (to demonstrate plasma membrane permeability) and the release of beta-glucuronidase (to indicate lysosomal permeability). Carbohydrate metabolism was monitored by the measurement of lactic acid production and, as one of the tests for macrophage function, the production of lysozyme was determined. The phagocytic ability of the cells was measured, after the addition of opsonized zymosan, by bioluminescence following luminol enhancement. Only some results could be evaluated, however, due to technical difficulties. A length- and dose-dependent cytotoxicity of the fibers was found in this system which was similar to that previously described with permanent cell lines. No great differences were found between fibers having different physicochemical compositions if their geometric dimensions were similar. Long, very thin fibers of glass, chrysotile, crocidolite and synthetic fluoroamphiboles were all toxic in the test system.

Cellular response to various chemical stimulants in the peritoneal cavity of the mouse.

A number of chemical substances were analysed for their effect on the total yield, differential count and cell volume of peritoneal exudate when administered parenterally. Inoculation of lysolecithin, thioglycolate and Freunds' complete adjuvant resulted in a cell-rich peritoneal lavage. Whereas the adjuvant-induced exudate was predominantly rich in polymorphonuclear cells, lysolecithin and thioglycolate produced maximum yield of mononuclear cells, with a mean spherical equivalent diameter bigger than those of the non-stimulated animals. The number of cells positive for non-specific esterase activity was significantly more in the stimulated animals.

Reaction of cells cultured in vitro to different asbestos dusts of equal surface area but different fibre length.

Peritoneal macrophages from mice were cultured in Leighton tubes and exposed to UICC chrysotile, crocidolite or amosite. Their cytotoxicity (Erythrosin uptake), release of lactate dehydrogenase (LDH) and uptake of 3H amino acids were determined according to weight (100 micrograms/tube), surface area (21.3 cm2 or fibre length. In all reactions tested chrysotile was more active than the amphiboles, but the latter gained activity if applied according to surface area. Uptake of 3H amino acids basis. Long-fibred asbestos dusts proved more cytotoxic than the corresponding short fibres when used on the basis of equal mass. In experiments with ascites tumour cells induced by nemalite the different asbestos dusts showed a very significant reduction of 3H-labelled thymidine uptake, but on weight basis the amphibole uptake was markedly higher.

Experimental pathology -- in vitro studies -- related to asbestos and other mineral fibres.

Current studies on the biologically relevant characteristics of inhalable fibres are described, including the papers presented in this session. The various cell systems used in in vitro tests, i.e., diploid and permanent proliferating and nonproliferating cells, are listed, as are the different endpoints of these tests. It is shown that use of in vitro tests complements the use of animal experimentation. Opinions on the nature of the acute toxic effects of asbestos fibres on macrophages differ; however, the dependence of toxicity on fibre length has been demonstrated in this system. These data show that the effects of mineral fibres in vitro give an indication of their potential fibrogenicity in vivo. Other cell culture systems, reported in papers in this session, include hamster lung fibroblasts, rat pleural mesothelial cells and mesothelioma cells. Experiments in which fibre geometry is altered, e.g., by acid treatment, indicate that it is an important factor in cytotoxicity; the haemolytic effect of fibres, however, appears to depend on their chemical composition. Thus, a combined physical-chemical effect would appear to be involved. In vitro testing has also made possible investigation of immunological and chromosomal changes due to inhalation of asbestos fibres. The practical use of findings made in vitro is also summarized.

Comparison of length-dependent cytotoxicity of inhalable asbestos and man-made mineral fibres.

Fibres of various defined length distributions were tested in vitro and in vivo. Tumour cells with phagocytic ability were used as the in vitro test system. DNA and protein synthesis and cell proliferation and enzyme release (LDH) were determined. Using gravimetrical and numerical doses in cultures, good indications of the toxicity of single fibres were found. It was possible to demonstrate clear-cut relationships between fibre length and cytotoxicity. In this test system, the toxicity of fibres increases with increasing length. The results of the cell experiments also furnish important indications of the doses of fibrous dusts to be used in animal tests and of the possibility of comparing different fibres with each other, especially with respect to the numerical or gravimetrical quantification of fibre fractions. Amosite, chrysotile, crocidolite and glass fibres of three or four different length spectra were tested.