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PubMedDate not supplied

Is atmospheric superoxide vitally necessary? Accelerated death of animals in a quasi-neutral electric atmosphere.

To estimate the necessity of air ions (AIs) as a natural source of atmospheric gaseous superoxide for mammalia the effect of air ion deprivation on mice and rats was investigated. Ambient air deionization inside an experimental acrylic glass cage (AGC) was performed by electrostatic field, built up by acrylic glass surfaces. Under these conditions, four hours after the animals were placed into the AGC, the concentration of negative AIs was not detectable, the concentration of positive ions was (mean +/- SD) 77 +/- 18 ions x cm-3. The negative and positive AI concentrations in identical silicate glass cages (control) were 482 +/- 128 ions x cm-3 and 660 +/- 148 ions x cm-3 respectively. It was found that the prolonged deficiency of AIs in ambient air leads to accelerated death of the animals. The life span of the deprived mice and rats was 16.2 +/- 0.9 and 23.0 +/- 1.1 days respectively. The pathological symptoms and ultrastructural changes in the adeno- and neurohypophysis in deprived animals observed strongly suggest that animal death is related to disturbances in neurohormonal regulation and pituitary insufficiency. The possible physiological need of AIs and atmospheric superoxide, and its role in the development of environmental stress in human beings and in particular in premature infants is discussed.

Air↗
PubMedDate not supplied

Formation of prebiochemical compounds in models of the primitive earth's atmosphere. II: CH4 - H2S atmospheres.

In order to understand the role of sulfur in the primitive atmosphere, we have studied the action of a silent discharge on mixtures of CH4 and H2S at low pressure. The nature of the products formed in the gaseous phase, and the influence of several parameters, especially the H2S percentage, on the yield of the products are reported. The analysis of the products is carried out by gas liquid chromatography and infrared spectrometry. The formation of sulfur-containing compounds, such as thiols and sulfides, is reported. CS2 is formed in high yield (a few percent) in mixtures containing 40-50% of H2S, while the maximum concentration of thiols (i.e., CH3SH and C2H5SH) is reached with lower percentages of H2S. The formation of hydrocarbons decreases rapidly with increasing proportions of H2S. These results show the important inhibitor effect of H2S on the formation of hydrocarbons and the possibility of occurrence of many sulfur compounds in prebiological evolution.

Atmosphere↗
PubMed1999

Atmospheric pressure chemical ionization of fluorinated phenols in atmospheric pressure chemical ionization mass spectrometry, tandem mass spectrometry, and ion mobility spectrometry.

Atmospheric pressure chemical ionization (APCI)-mass spectrometry (MS) for fluorinated phenols (C6H5-xFxOH Where x = 0-5) in nitrogen with Cl- as the reagent ion yielded product ions of M Cl- through ion associations or (M-H)- through proton abstractions. Proton abstraction was controllable by potentials on the orifice and first lens, suggesting that some proton abstraction occurs through collision induced dissociation (CID) in the interface region. This was proven using CID of adduct ions (M Cl-) with Q2 studies where adduct ions were dissociated to Cl- or proton abstracted to (M-H)-. The extent of proton abstraction depended upon ion energy and structure in order of calculated acidities: pentafluorophenol > tetrafluorophenol > trifluorophenol > difluorophenol. Little or no proton abstraction occurred for fluorophenol, phenol, or benzyl alcohol analogs. Ion mobility spectrometry was used to determine if proton abstraction reactions passed through an adduct intermediate with thermalized ions and mobility spectra for all chemicals were obtained from 25 to 200 degrees C. Proton abstraction from M Cl- was not observed at any temperature for phenol, monofluorophenol, or difluorophenol. Mobility spectra for trifluorophenol revealed the kinetic transformations to (M-H)- either from M Cl- or from M2 Cl- directly. Proton abstraction was the predominant reaction for tetra- and penta-fluorophenols. Consequently, the evidence suggests that proton abstraction occurs from an adduct ion where the reaction barrier is reduced with increasing acidity of the O-H bond in C6H5-xFxOH.

Atmospheric Pressure↗
PubMed2004

Determination of carbamate pesticide residues in vegetables and fruits by liquid chromatography-atmospheric pressure photoionization-mass spectrometry and atmospheric pressure chemical ionization-mass spectrometry.

A liquid chromatography-atmospheric pressure photoionization (APPI)-mass spectrometry method was developed for the determination of 22 carbamates including their metabolites in vegetables and fruits. For the optimization of APPI, several APPI ion source parameters were examined. As a result, many carbamates with APPI using the optimized parameter gave simple mass spectra, and a strong signal corresponding to [M + H](+) was observed except for aldicarb. However, some carbamate metabolites gave ammonium adduct ions [M + NH(4)](+) as base peak ions. The mean recovery of each carbamate from grape and onion samples spiked at 5 ng/g was 81.7-105.7%, with relative standard deviations of 3.3-5.9%. Furthermore, matrix constituents did not significantly influence the ionization efficiency. The limit of detection (S/N = 3) in grape and onion was in the range of 0.33-3.33 ng/g. For the robustness of this method, this system has been used to analyze 50 samples, and the intensities for all carbamates were found to be unaffected by the contamination of the APPI source by sample matrix constituents. This result indicates that the method is reliable.

Atmospheric Pressure↗
PubMed1984

Allergen carriage by atmospheric aerosol. II. Ragweed-pollen determinants in submicronic atmospheric fractions.

Outdoor air was drawn by a vacuum system through a 0.8 micron molecular membrane filter and a back-up, refrigerated condensor from 8 A.M. to 5 P.M. daily during the 1982 ragweed-pollen season. Sample sets from each day were collected and stored separately. Condensate was collected in a freezing jacket, thawed, refiltered through a 0.45 micron filter, and lyophilized. Reconstituted condensates evoked wheal-and-flare skin reactions in a ragweed-sensitive individual and produced significant inhibition in an IgG-ELISA system by use of ragweed-pollen protein or ragweed antigen E conjugated to polystyrene microtiter plates, pooled serum of patients on ragweed immunotherapy, and alkaline phosphatase-labeled anti-human IgG. Earlier, in 1983 in this JOURNAL, we reported the presence of airborne ragweed-pollen antigen in aerosol fractions below 5 micron. The present data demonstrate similar in filtrates well below the micronic range. Furthermore, these antigenic properties are substantially associated with atmospheric water vapor-either naturally or as a readily-induced result of the collection procedure. These results suggest that naturally occurring mists, although free of native particulates, may yet carry allergens of clinical significance.

Air Pollutants↗
PubMed2004

Characterization of atmospheric concentrations and partitioning of PAHs in the Chicago atmosphere.

An intensive sampling program has been undertaken in the absence of precipitation at an urban site, Chicago, to characterize the atmospheric concentration and partitioning of PAHs. Two different sampling programs have been carried out with a large number of samples. Measured ambient concentrations of PAHs were classified as Land and Lake samples based on wind direction and back trajectory calculations. Differences in ambient concentrations of PAHs were observed between Land and Lake samples. The concentrations of PAHs when air originated over the Land were approximately two-four times higher than the concentrations measured when air originated over the Lake. It has been demonstrated that partitioning of PAHs shows a consistent difference between samples taken when wind came from off the land rather than off the water. This was most evident by more shallow slopes for Lake samples compared to the slopes for Land samples, when partition coefficient (K(p)) is plotted on a log-log scale vs. the subcooled liquid vapor pressure (P(L)(0)). Experimentally, determined K(p) values were compared with the results obtained using two different models, one based on absorption into aerosol organic matter and the other adsorption onto soot carbon. Experimental K(p) values generally agreed well with the soot+octanol based model predictions.

Adsorption↗
PubMed2005

Atmospheric emission inventory of the Maurienne valley for an atmospheric numerical model.

Within the framework of an air quality study of the French alpine valleys (POVA program), an atmospheric emission inventory concerning major pollutants: CO, NOx, SO(2), CH(4), particles (PT) and non-methane volatile organic compounds (NMVOC) was carried out. This inventory has a spatial resolution of 1 km(2) and was established for the reference year 2003. The coexistence of economic activities and the Vanoise national park makes the Maurienne valley a sensitive site, particularly representative of the problems of sustainable development in alpine areas, where air pollution is one of the most important aspects. The area, which covers 4588 km(2), is an alpine valley that is sensitive to air pollution due to the emission sources (traffic, industries, private heating, etc.), its morphology (a narrow valley surrounded by high ranges), and local meteorology (temperature inversions and slope winds). As expected, the result which includes both biogenic and anthropogenic sources shows serious emissions of pollutants that are mainly due to the presence of highways and industries around. Two emission inventories were drawn up: one with emission factors determined by CORINAIR (from the European Environment Agency) and the other with emission factors determined by BUWAL-OFEFP (from Swiss Agency for the Environment, Forests and Landscape). The inventories were then compared thanks to concentrations calculated from a numerical model. Computations were run for an intensive field observation period from 25 June to 2 July 2003.

Air Pollutants↗
PubMed2004

Fate of elemental mercury in the Arctic during atmospheric mercury depletion episodes and the load of atmospheric mercury to the Arctic.

Atmospheric mercury depletion episodes (AMDEs) were studied at Station Nord, Northeast Greenland, 81 degrees 36' N, 16 degrees 40' W, during the Arctic Spring. Gaseous elemental mercury (GEM) and ozone were measured starting from 1998 and 1999, respectively, until August 2002. GEM was measured with a TEKRAN 2735A automatic mercury analyzer based on preconcentration of mercury on a gold trap followed by detection using fluorescence spectroscopy. Ozone was measured by UV absorption. A scatter plot of GEM and ozone concentrations confirmed that also at Station Nord GEM and ozone are linearly correlated during AMDEs. The relationship between ozone and GEM is further investigated in this paper using basic reaction kinetics (i.e., Cl, ClO, Br, and BrO have been suggested as reactants for GEM). The analyses in this paper show that GEM in the Arctic troposphere most probably reacts with Br. On the basis of the experimental results of this paper and results from the literature, a simple parametrization for AMDE was included into the Danish Eulerian Hemispheric Model (DEHM). In the model, GEM is converted linearly to reactive gaseous mercury (RGM) over sea ice with temperature below -4 degrees C with a lifetime of 3 or 10 h. The new AMDE parametrization was used together with the general parametrization of mercury chemistry [Petersen, G.; Munthe, J.; Pleijel, K.; Bloxam, R.; Vinod Kumar, A. Atmos. Environ. 1998, 32, 829-843]. The obtained model results were compared with measurements of GEM at Station Nord. There was good agreement between the start and general features periods with AMDEs, although the model could not reproduce the fast concentration changes, and the correlation between modeled and measured values decreased from 2000 to 2001 and further in 2002. The modeled RGM concentrations over the Arctic in 2000 were found to agree well with the temporal and geographical variability of the boundary column of monthly average BrO observed by the GOME satellite. Scenario calculations were performed with and without AMDEs. For the area north of the Polar Circle, the mercury deposition increases from 89 tons/year for calculations without an AMDE to 208 tons/year with the AMDE. The 208 tons/year represent an upper limit for the mercury load to the Artic.

Air Pollutants↗
PubMed2005

Atmospheric chemistry of hydrofluoroethers: Reaction of a series of hydrofluoroethers with OH radicals and Cl atoms, atmospheric lifetimes, and global warming potentials.

The kinetics of the OH radical and Cl atom reactions with nine fluorinated ethers have been studied by the relative rate method at 298 K and 1013 hPa using gas chromatography-mass spectroscopy (GC-MS) detection: k(OH + CH3CH2OCF3) = (1.55 +/- 0.25) x 10(-13), k(OH + CF3CH2OCH3) = (5.7 +/- 0.8) x 10(-13),k(OH + CF3CH2OCHF2) = (9.1 +/- 1.1) x 10(-15), k(OH + CF3CHFOCHF2) = (6.5 +/- 0.8) x 10(-15), k(OH + CHF2CHFOCF3) = (6.8 +/- 1.1) x 10(-15), k(OH + CF3CHFOCF3) < 1 x 10(-15), k(OH + CF3CHFCF2OCHF2) = (1.69 +/- 0.26) x 10(-14), k(OH + CF3CHFCF2OCH2CH3) = (1.47 +/- 0.13) x 10(-13), k(OH + CF3CF2CF2OCHFCF3) < 1 x 10(-15), k(Cl + CH3CH2OCF3) = (2.2 +/- 0.8) x 10(-12), k(Cl + CF3CH2OCH3) = (1.8 +/- 0.9) x 10(-11), k(Cl + CF3CH2OCHF2) = (1.5 +/- 0.4) x 10(-14), k(Cl + CF3CHFOCHF2) = (1.1 +/- 1.9) x 10(-15), k(Cl + CHF2CHFOCF3) = (1.2 +/- 2.0) x 10(-15), k(Cl + CF3CHFOCF3) < 3 x 10(-15), k(Cl + CF3CHFCF2OCHF2) < 6 x 10(-16), k(Cl + CF3CHFCF2OCH2CH3) = (3.1 +/- 1.1) x 10(-12), and k(Cl + CF3CF2CF2OCHFCF3) < 3 x 10(-15) cm3 molecule(-1) s(-1). The error limits include three standard deviations (3 sigma) from the statistical data analyses, as well as the errors in the rate coefficients of the reference compounds that are used. Infrared absorption cross sections and estimates of the trophospheric lifetimes and the global warming potentials of the fluorinated ethers are presented. The atmospheric degradation of the compounds is discussed.

Journal Article↗
PubMed2006

Effects of polyvinyl chloride overwrap film, high-oxygen modified atmosphere packaging, or ultra-low-oxygen modified atmosphere packaging on bone marrow discoloration in beef humerus, rib, thoracic vertebra, and scapula.

Meat retailers have reported bone marrow discoloration to be a problem, especially in modified atmosphere packages (MAP). Therefore, it is important to determine the prevalence and cause(s) of bone marrow discoloration in different beef bones and packaging systems. Thirty-six beef humeri, ribs, scapulas, and thoracic vertebrae from USDA Select and Choice carcasses were obtained from a commercial abattoir, cut into 2.54-cm-thick sections at 4 d postmortem, and packaged into 1 of 3 systems: 1) polyvinyl chloride film (PVC) overwrap; 2) high-oxygen (80% O2, 20% CO2) MAP; and 3) ultra-low-oxygen (70% N2, 30% CO2) MAP. Instrumental reflectance and visual color scores were taken on d 0, 2, and 4, and on d 0 to 4 of display, respectively. Bone marrow was extracted from humeri, ribs, and thoracic vertebrae for analysis but not from scapulas. Ribs, scapulas, and thoracic vertebrae packaged in PVC and high-oxygen MAP developed undesirable gray or black discoloration. In ultra-low-oxygen MAP, mean visual color scores were acceptable throughout the entire display period. Discoloration (darkening) was more extensive for ribs, scapulas, and thoracic vertebrae than for humeri, especially for bones packaged in PVC and high-oxygen MAP. Humeri had lower (P < 0.05) a* values (larger positive a* values indicate a redder color) than the other bones. The a* values for ribs, scapulas, and thoracic vertebrae decreased (P < 0.05) over time. Chroma showed that bone marrow discolored during display, but graying was dramatically less for all bones packaged in ultra-low-oxygen MAP and for humeri in PVC and high-oxygen MAP. Humeri marrow had lower (P < 0.05) 2-thiobarbituric acid reactive substances (TBARS) than did ribs and thoracic vertebrae marrow. Ultra-low-oxygen MAP resulted in the least amount of change in TBARS from d 0 to 4, whereas thoracic vertebrae marrow had greater (P < 0.05) TBARS values at d 4 of display than at d 0 in PVC and high-oxygen MAP. Humeri marrow had dramatically less total Fe and hemoglobin than did that of ribs and thoracic vertebrae for all packaging systems. Myoglobin was undetectable in humeri marrow. The much larger amounts of Fe and hemoglobin in ribs and thoracic vertebrae likely contribute to marrow discoloration. Bone marrow discoloration was distinct in ribs, scapulas, and thoracic vertebrae packaged in PVC or high-oxygen MAP. Bones packaged in ultra-low-oxygen MAP had minimal discoloration.

Animals↗
PubMed1997

[Marked increase of atmospheric pollen dispersion of ragweed (Ambrosia spp.)--annual changes in atmospheric pollen counts of major allergen plants in autumn in Saitama Prefecture].

An annual atmospheric pollen survey was performed for 14 consecutive years in the autumn at Sakado city, Saitama prefecture. The survey was performed on the transition of pollen dispersion of major allergen plants: ragweed (Ambrosia spp.), Humulus japonicus, Artemisia spp. and Gramineae. 1. Annual total pollen count of ragweed showed marked increases beginning from 1991. Total pollen count in 1991 was 8.8 times and that in 1996 was 18.6 times that in 1983. This increase is probably caused by marked proliferation of giant ragweed which is left without mowing as it is on a dry riverbed, and consequently produces much more pollen than short ragweed. 2. Annual increases in total pollen counts of other major plants which disperse their pollen in the same season as ragweed were 0.95 times in 1991 and 0.5 times in 1996 that in 1983 for Humulus japonicus, 0.68 times in 1991 and 1.5 times in 1996 that in 1983 for Artemisia spp. and 1.3 times in 1991 and 1.4 times in 1996 that in 1983 for Gramineae. None of these species showed a marked increase of pollen dispersion although they showed some annual variation. The above findings suggest that changes in the proliferous state of various allergenic plants due to environmental change should be considered with respect to characteristics of pollen allergy.

Air Pollution↗
PubMed2005

Trends in atmospheric ammonium concentrations in relation to atmospheric sulfate and local agriculture.

Ammonium (NH(4)(+)) concentrations in air and precipitation at the Institute of Ecosystem Studies (IES) in southeastern New York, USA declined over an 11-year period from 1988 to 1999, but increased from 1999 to 2001. These trends in particulate NH(4)(+) correlated well with trends in particulate SO(4)(2-) over the 1988-2001 period. The NH(4)(+) trends were not as well correlated with local cattle and milk production, which declined continuously throughout the period. This suggests that regional transport of SO(4)(2-) may have a greater impact on concentrations of NH(4)(+) and subsequent deposition than local agricultural emissions of NH(3). Ammonium concentrations in precipitation correlated significantly with precipitation SO(4)(2-) concentrations for the 1984-2001 period although NH(4)(+) in precipitation increased after 1999 and SO(4)(2-) in precipitation continued to decline after 1999. The correlation between NH(4)(+) and SO(4)(2-) was stronger for particulates than for precipitation. Particulate NH(4)(+) concentrations were also correlated with particulate SO(4)(2-) concentrations at 31 of 35 eastern U.S. CASTNet sites that had at least 10 years of data. Air concentrations of NH(4)(+) and SO(4)(2-) were more strongly correlated at the sites that were located within an agricultural landscape than in forested sites. At most of the sites there was either no trend or a decrease in NH(4)(+) dry deposition during the 1988-2001 period. The sites that showed an increasing trend in NH(4)(+) dry deposition were generally located in the southeastern U.S. The results of this study suggest that, in the northeastern U.S., air concentrations of NH(4)(+) and subsequent deposition may be more closely linked to SO(4)(2-) and thus SO(2) emissions than with NH(3) emissions. These results also suggest that reductions in S emissions have reduced NH(4)(+) transport to and NH(4)(+)-N deposition in the Northeast.

Agriculture↗