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Among the many risk factors for the development of atopic eczema (AE), the influence of air pollution has recently been discussed more often. A systematic review about this topic however is lacking.Which effects of outdoor air pollution (particles, nitric oxides, sulfur dioxide, ozone or general traffic exhaust emissions) on AE can be demonstrated in a systematic analysis of available environmental epidemiologic studies?All environmental epidemiologic studies on AE and air pollution found in the literature database PubMed were identified. The most important key figures of these studies were tabulated, the quality of evidence was graded and the studies described.A total of 57 studies were identified. Only one of the 15 cross-sectional studies with a large-scale exposure assessment found a significant association between AE and air pollution. In contrast 23 of 30 studies with small-scale exposure assessment found a significant association between AE and traffic related emissions-especially from trucks. Of the 30 studies, 14 were cohort studies (1 adult, 13 birth cohorts). The sole adult cohort found an association with intrinsic AE. In the East Asian cohorts (all published since 2015), an association between maternal exposure to traffic-related pollution and incidence of AE in the offspring was found. This was less clear in cohorts from Europe/US or simply not investigated. In 5/5 panel studies (all from South Korea), symptom severity of AE was found to be significantly and positively related to outdoor air pollution.In a systematic analysis of environmental epidemiologic studies about air pollution and AE rather good evidence was found that, based on small-scale exposure measurements, especially truck traffic emissions increased AE prevalence, while large-scale exposure to larger particles (PM10) or SO

Diese Arbeit beschäftigt sich mit der elektrochemischen und chemischen Charakterisierung des anorganischen Batterieelektrolyten LiAlCl₄ in Schwefeldioxid. Der Schwerpunkt war die Bestimmung der Überführungszahl, eines wichtigen Transportparameters für Batterieelektrolytsysteme. Es werden die theoretischen Grundlagen zusammenfassend dargestellt und die verschiedenen Methoden zur Überführungszahlbestimmung kurz erklärt. Die Überführungszahlbestimmungen mit der Methode nach Hittorf und der Methode mittels DOSY-NMR-Spektroskopie werden ausführlicher diskutiert, da sie in dieser Arbeit auch praktische Anwendung an dem Elektrolyten LiAlCl₄ x 1.6 SO₂ fanden. Im Zuge dieser Arbeit wurden außerdem verschiedene Hittorf-Zellen aus Glas entworfen. Das Design wurde unter Zuhilfenahme der entsprechenden Literatur und praktischer Tests dahingehend optimiert, dass sich die Teilräume aufgrund von induzierten Konvektionsströmen weitestgehend nicht durchmischen, sich die Messzelle temperieren lässt, die Entleerung der Teilräume unter Atmosphärenausschluss stattfinden kann und eine Zellkonstante besitzt, so dass die Zelldimensionen und das benötigte Elektrolytvolumen akzeptabel sind. Des Weiteren ist für die Überführungszahlbestimmung nach der Hittorf-Methode eine besonders genaue Konzentrationsbestimmung vonnöten. Eine ausreichend genaue Lithium-Ionen-Konzentrationsbestimmung, die den Ansprüchen an die Hittorf-Messung gerecht wird, ist die indirekte Bestimmung über die Chlorid-Ionen, die sich nach vollständiger Hydrolyse des Elektrolyten LiAlCl₄/SO₂ mittels einer potentiometrischen Fällungstitration mit Silbernitrat sehr sensitiv bestimmen lassen. Weiterhin führt auch für diesen anorganischen Batterieelektrolyten eine Wasserkontamination zum Start irreversibler autokatalytischer Prozesse, die die Performance und Lebenszeit der Zelle negativ beeinflussen. Da der Elektrolyt zusätzlich mit Wasser reagiert, ist eine gängige Analysemethode, wie Karl-Fischer Titration, nicht möglich gewesen. In dieser Arbeit wurde die Wasserkontamination des Elektrolyten mittels ¹H-NMR-Spektroskopie bestimmt. Die außergewöhnlich hohe Lithiumionen-Überführungszahl von konzentrierten LiAlCl₄/SO₂ Lösungen gegenüber gängigen Elektrolytlösungen auf Basis organischer Carbonate, macht diese besonders attraktiv für Hochleistungs-Lithium-Ionen Batterien, da dadurch die Konzentrationspolarisation an den Elektroden sehr gering ist. Außerdem ist dieser Elektrolyt sehr schwer entflammbar, was ihn ebenfalls besonders attraktiv macht, da die aktuell weit verbreiteten Elektrolyte auf Basis von organischen Carbonaten brennbar sind., This thesis is concerned with the electrochemical and chemical characterization of the inorganic electrolyte LiAlCl₄/SO₂ for lithium-ion batteries. The project's main focus is on determining the transference number, which is an important transport parameter for battery electrolytes. Both the theoretical basics and an overview of several methods for determining transference numbers are also included. Moreover, the transference number determination of the electrolyte LiAlCl₄ x 1.6 SO₂ using Hittorf’s method and DOSY-NMR-spectroscopy are discussed in greater detail, as they are applied to the electrolyte as well. For the purpose of this thesis, several Hittorf cells were made out of glass. The cell design was optimized both through the review of the appropriate literature and practical experiments. Because of that, the intermixture of the cell compartments by induced convection flow was avoided, and the precise temperature control of the measurement cell could be guaranteed. It also made the draining of the compartments in inert gas conditions possible, and led to the optimization of the measurement cell by taking into consideration the electrolyte’s conductivity, acceptable cell dimensions, and a passable volume of the electrolyte. In order to obtain reliable transference numbers, a precise determination of lithium ion concentration is essential. A suitable method for the electrolyte LiAlCl₄/SO₂ is the indirect determination via potentiometric precipitation titration of chloride with silver nitrate after full hydrolysis of the electrolyte. Contamination of the battery electrolyte with water also initiates irreversible autocatalytic degradation processes, which in turn lead to loss of performance and reduced battery lifetime. As the electrolyte reacts with water, water content analysis via Karl-Fischer titration was not applicable. Therefore, the method of choice for this project was the determination of water content by means of ¹H-NMR spectroscopy. Concentrated solutions of LiAlCl₄ in sulfur dioxide show an extraordinarily high transference number of the lithium cation compared to the widely-used lithium-ion battery electrolytes based on organic carbonates. This characteristic results in a very low concentration polarization at the electrodes and makes the electrolyte a promising alternative for lithium ion cells with high power ability. Furthermore, this electrolyte has the advantage of being almost non-inflammable when compared to the widely-used battery electrolytes that are based on organic solvents.

Seit der ersten gezielten Nutzung von Feuer durch den Menschen spielt anthropogene Luftverunreinigung eine Rolle, und spätestens seit Beginn der Industrialisierung von Gesellschaften ist sie zu einem schwerwiegenden Problem geworden. Verunreinigte Luft ist eine Gesundheitsgefährdung, die die gesamte Erdbevölkerung betrifft, da sie an Staatsgrenzen nicht stoppt. Bestrebungen zur Verbesserung der Luftqualität zielen dabei vor allem auf die anthropogene Luftverschmutzung als einzigen beeinflussbaren Faktor ab und sollten möglichst überregional gestaltet werden. Hauptursachen für anthropogene Luftverunreinigungen sind der Straßenverkehr als mobile Quelle und Prozesse der Energieerzeugung und Industrie als stationäre Quellen. In dieser Arbeit wird erstmals eine szientometrische Analyse der Forschungsaktivität zum Thema Luftverschmutzung und hier besonders zur Verunreinigung durch Feinstaub und Schwefeldioxid durchgeführt. Dabei werden Artikel analysiert, die in den Online-Datenbanken „PubMed“ und „Web of Science“ erfasst sind. Zum Thema Feinstaub und Schwefeldioxid wird innerhalb der Ergebnisse zur Luftverschmutzung gesucht („Web of Science“), bzw. die Suche über die MeSH- Database mit der zur Luftverschmutzung verknüpft („PubMed“). Zur Datenauswertung und bildlichen Darstellung werden teilweise selbst entwickelte Programme genutzt, internationale Übersichten zu Veröffentlichungsanzahlen und Zitationsraten werden mit der Density-Equalizing-Methode dargestellt. Die Analyse ergibt im Zeitraum von 1955 bis 2006 im „Web of Science“ 26.253 und bei „PubMed“ 28.416 Veröffentlichung für Luftverschmutzung, 3567 bzw. 2738 Publikationen zum Feinstaub und 1440 bzw. 1068 Datenbankeinträge für Schwefeldioxid. Die Veröffentlichungszahlen steigen im „Web of Science“ innerhalb des Analysezeitraums konstant an, während sich in „PubMed“ Mitte der 1970er Jahre eine Spitze in den jährlichen Publikationszahlen zeigt; beiden Datenbanken ist ein rasanter Anstieg der Veröffentlichungszahlen ab Anfang der 1990er Jahre gemeinsam. So steigen auch die Zitierungen der Artikel pro Jahr ab 1991 an, jedoch überproportional zu den Publikationszahlen; dies gilt für alle drei Analysen und ist vor allem im Zusammenhang mit der Einführung des World Wide Web für die Öffentlichkeit Anfang der 1990er Jahre sowie einer öffentlich entbrannten Diskussion zur Luftreinheit Anfang der 1990er Jahre zu sehen. Dass Englisch die derzeitige Sprache der Wissenschaft ist, bestätigt die Tatsache, dass 96% (80% für Feinstaub und 97% für Schwefeldioxid) der Publikationen in englischer Sprache verfasst sind. Weitere häufiger genutzte Sprachen sind Deutsch und Französisch. Der größte Anteil der Publikationsaktivität ist den USA zuzuschreiben (38% für Luftverschmutzung, 40% für Feinstaub und 30% für Schwefeldioxid). So gilt auch die höchste Anzahl an Zitierungen US-amerikanischen Veröffentlichungen; bei der Errechnung der Zitationsraten treten zunächst Länder mit geringen Publikationszahlen und Teilnahme an großen internationalen Studien in den Vordergrund, nach Aufdecken dieses statistischen Mangels zeigen sich europäische Staaten (Feinstaub, Schwefeldioxid) und Neuseeland vor südamerikanischen Ländern (Luftverschmutzung) führend. Angesichts der hohen Dichte so genannter Megastädte im asiatischen Raum erscheint die Abwesenheit von asiatischen Veröffentlichungen unter den häufig zitierten verwunderlich. Unter den produktivsten Autoren finden sich hauptsächlich US-amerikanische, so auch der meist publizierende, J. Schwartz, daneben auch europäische und ein kanadischer. Zur Thematik Schwefeldioxid überwiegt der Anteil der europäischen Autoren. Die Anzahl der ihnen zugeordneten Veröffentlichungen korreliert weder mit der Anzahl der Listungen als Erstautor noch mit dem für sie errechneten h-Index. Bei näherer Betrachtung ist der Hauptanteil der Zitierungen ihrer Werke auf Selbstzitierungen oder bevorzugte Zitate von durch Kooperationen mit anderen Autoren entstandenen Werken zurückzuführen. Hier kann von einer bewussten Einflussnahme auf eigene bibliometrische Werte ausgegangen werden, was ein häufiges Phänomen in der Wissenschaft darstellt. Die mit Abstand häufigste Veröffentlichungsform ist der Artikel. Die Forschungsgebiete der produktivsten Zeitschriften setzen sich hauptsächlich aus umweltwissenschaftlichen Themen zusammen, hier sind in allen drei Analysen für „Atmospheric Environment“ die meisten Erscheinungen eingetragen. Weiterhin findet sich eine Zeitschrift mit epidemiologischem Schwerpunkt und zwei mit medizinischen Inhalten (respiratorisches System). Die Impact Factors korrelieren nicht mit der Produktivität der Zeitschriften, die Werte für Cited Half-Life und Immediacy Index deuten auf nicht schnelllebige Wissenschaftsfelder hin. Die Ergebnisse der Zeitschriftenanalyse widerspiegelnd, sind unter den forschenden Fachgebieten die Umweltwissenschaften am produktivsten. Die vier relevanten medizinischen Fachbereiche geben die schon bei den Zeitschriften auffallende Unterrepräsentanz von gesundheitlichen Themen wieder; gleichzeitig ist die schon erfolgte Aufteilung in Unterthemen zu beachten, während die Umweltwissenschaften ein großes Themengebiet darstellen. Unter den analysierten Organsystemen wurde der Lunge die größte Aufmerksamkeit geschenkt, was sich angesichts ihrer Funktion als Eintrittspforte von u. a. Luftschadstoffen einfach nachvollziehen lässt. Auch andere nennenswerte Organsysteme zeichnen sich durch direkten Luftkontakt bzw. unmittelbare funktionelle Nähe zum respiratorischen System aus. Hohe Publikationszahlen für Luftverschmutzung durch Feinstaub im Zusammenhang mit der Leber lassen sich durch kürzlich angenommene funktionelle Schädigungszusammenhänge über eine Rechtsherzinsuffizienz erklären., Ever since the first purposeful utilization of fire by humankind, anthropogenic air pollution has been an issue. At least by the beginning of the industrialization it has become a severe problem. Today, the main causes of anthropogenic air pollution are road traffic (a “mobile” source), and processes in energy production and industry (“stationary” sources). Efforts to improve air quality are mainly aimed at anthropogenic air pollution, as it is the only susceptible factor. Polluted air is a health hazard of concern for the world population as a whole, since it does not stop at national borders. Therefore, efforts towards air quality imp ovement should be organized at a supra-regional level, when feasibility is indicated. In this paper, the first scientometric analysis of the research activity concerning the field of air pollution is accomplished, with particular attention to particulate matter and sulfur dioxide. Articles in the online databases “PubMed” and “Web of Science” are analyzed. Results for particulate matter and sulfur dioxide are retrieved from the sum of results for the air pollution analysis (“Web of Science”), or linked to the same by the MeSH-database (“PubMed”). In part, proprietary program codes are used to evaluate and illustrate data. International diagrams to demonstrate publication numbers and citation rates are generated by means of density-equalizing mapping to demonstrate publication numbers and citation rates. For the time span 1955-2006, the analysis shows 26,253 results in “Web of Science” and 28,416 in “PubMed” for air pollution. More specifically, for particulate matter, “Web of Science” lists 3567 publications while “PubMed” 2738 entries; for sulfur dioxide 1440 and 1068 publications respectively. During the analysis period, the number of publications increased in “Web of Science” over time, whereas in “PubMed” a peak in yearly publications occurred in the mid-1970s. However, both databases display a rapid slope in publication numbers at the beginning of the 1990s. Therefore, citation numbers rise beginning in 1991, too, but disproportionately high to publications. This is applicable for all three analyses and is to be mainly ascribed to the implementation of the World Wide Web to the public in the beginning of the 1990s as well as to a public discussion about air quality beginning in the early 1990s. The fact that 96% of the publications are written in English (80% for particulate matter and 97% for sulfur dioxide) supports the notion that English has become the main language for scientific literature. Other frequently used languages are German and French. The largest part of publication activity is attributable to research in the USA (38% for air pollution, 40% for particulate matter and 30% for sulfur dioxide). Therefore the highest numberof citations is found for US-American publications; calculating the citation rates, countries with low publication numbers participating in large international studies are on top of the agenda at first. Eliminating this statistical deficiency, European states (particulate matter, sulfur dioxide) and New Zealand (air pollution) are leading ahead of South American countries. Regarding the high density of so-called mega-cities in the Asian area, the lack of Asian publications among the frequently cited seems rather remarkable. Mainly US-Americans are to be found among the most productive authors including the most publishing one, J. Schwartz, alongside with Europeans and one Canadian author. Regarding the topic of sulfur dioxide, European authors are prevailing. Publication numbers neither correlate with the number of entries as first author nor with the h-indexes. Under closer inspection, the largest fraction of citations is to be ascribed to self- citations or preferential citations of papers that derive from co-operations with other authors. Here, an intentional influence on bibliometric accounts can be assumed, which is a common phenomenon in science. The article is by far the most frequent document type. The most productive journals‟ subject areas mainly consist of themes originating from the environmental sciences. Most entries are papers from “Atmospheric Environment” in all three analyses. Furthermore, there is one journal with an epidemiological emphasis and two journals with medical content (respiratory system). The impact factors do not correlate with the journals‟ productivity; values for cited half-life and immediacy index do not suggest fast moving fields of science. Mirroring the results of the journal analysis, environmental sciences are the most productive among the researching subject areas. The fact that there are four relevant medical fields reflects that health-related topics are underrepresented. This was already shown in the journals‟ analysis. At the same time, there has to be some attention paid to the fact that the medical topics are partitioned into sub-themes, while the environmental sciences are a large field containing many possible sub-themes. The most attention among the analyzed organ systems is paid to the lung, which is easily understandable, considering its function as the entrance for air pollutants. Other relevant organ systems are characterized by direct air contact or immediate functional closeness to the respiratory system. High publication numbers regarding particulate air pollution in combination with the liver can be explained by recently assumed functional coherence in damaging mechanisms by means of a right heart insufficiency.

Pollen von Hasel, Erle, Birke, Honiggras und Beifuß wurden im Wirbelschichtreaktor gegenüber unterschiedlichen relativen Luftfeuchten (0 bis 80 % rF) und SO2-Konzentrationen (0,0076 bis 5 ppm SO2) für 9 Stunden exponiert. Für Honiggras- und Beifußpollen konnte eine signifikante zeitabhängige negative Korrelation zwischen relativer Luftfeuchte und der extrahierbaren Proteinmenge festgestellt werden. Dieser Effekt wurde durch SO2 konzentrations- und zeitabhängig reduziert. Die Ergebnisse sind durch hydrodynamische Regelprozesse zu erklären und deuten auf einen Einfluß von Umweltfaktoren auf atmosphärische Allergenkonzentrationen. In simulating natural air conditions pollen from hazel, alder, birch, meadow velvet and mugwort were exposed to synthetic air with different relative humidities (from 0 to 80 % rH) and concentrations of sulfur dioxide (from 0.0076 to 5 ppm SO2) for up to 9 hours in a fluidized bed reactor. A significant time dependant negative correlation between rH and protein content in the pollen extracts could be shown for meadow velvet and mugwort pollen. The effect was reduced by SO2 in a concentration and time dependant manner. This finding might be due to hydrodynamic mechanisms and sheds new light on the influence of environmental factors on atmospheric allergen concentrations.

Die vorliegende Arbeit beschäftigt sich mit der Löslichkeit von Gasen in chemisch reagierenden wässrigen Lösungen. Dabei werden zwei Beispiele näher betrachtet: Die simultane Löslichkeit von Ammoniak und Schwefeldioxid in wässrigen salzhaltigen Lösungen und die Löslichkeit von Kohlendioxid in wässrigen Lösungen von N-Methyldiethanolamin (MDEA), Piperazin und deren Mischungen. Die Phasengleichgewichte in solchen Systemen werden wesentlich durch die in der flüssigen Phase auftretenden chemischen Reaktionen und die dabei entstehenden ionischen Spezies beeinflusst. Die Lösungen weisen auch aufgrund der weitreichenden Coulombschen Wechselwirkungen ein stark reales Verhalten auf. Die Untersuchungen der vorliegenden Arbeit bauen auf früheren Arbeiten am Lehrstuhl für Technische Thermodynamik der Technischen Universität Kaiserslautern auf. In diesen Arbeiten wurden u.a. Modelle zur Beschreibung des Dampf-Flüssigkeits-Gleichgewichtes in den Systemen NH3+SO2+((NH4)2SO4 oder Na2SO4)+Wasser und CO2+MDEA+Piperazin+Wasser entwickelt. Diese Modelle wurden hier weiterentwickelt und verbessert. Beim System Ammoniak+Schwefeldioxid+Wasser wurde mittels ATR-IR-spektroskopischer Untersuchungen festgestellt, dass Pyrosulfit in den wässrigen Lösungen in nicht zu vernachlässigbarem Umfang auftritt. Deshalb muss die chemische Reaktion der Pyrosulfitbildung berücksichtigt werden, wenn die thermodynamischen Eigenschaften solcher Lösungen zuverlässig beschrieben werden sollen. Die chemische Gleichgewichtskonstante für die Pyrosulfitbildungsreaktion wurde aus IR-spektroskopischen und kalorimetrischen Untersuchungen des Systems Na2S2O5+H2O ermittelt. Das Modell zur Beschreibung des Dampf-Flüssigkeits-Gleichgewichtes und der Enthalpieänderung beim Verdünnen des Systems NH3+SO2+((NH4)2SO4 oder Na2SO4)+Wasser wurde zur Berücksichtigung sowohl der Pyrosulfitbildungsreaktion als auch der neuen experimentellen Daten für die Verdünnungsenthalpie von Meyer [70] erweitert. Das Modell ermöglicht Vorhersagen für das Dampf-Flüssigkeits-Gleichgewicht und Enthalpieänderungen der quaternären Systeme. Während die Gaslöslichkeit im System NH3+SO2+Na2SO4+Wasser zuverlässig beschrieben wird, sind die Vorhersagen für das Dampf-Flüssigkeits-Gleichgewicht des Systems NH3+SO2+(NH4)2SO4+Wasser nicht so gut. Ein Grund dafür mag darin liegen, dass bei den Untersuchungen an diesem System die Ionenstärke deutlich größer war (I=20 molal) als bei den Untersuchungen am System NH3+SO2+Na2SO4+Wasser (I=10 molal). Die Verdünnungsenthalpie wird für beide quaternäre Systeme gut vorhergesagt. Mithilfe NMR-spektroskopischer Untersuchungen am System CO2+Piperazin+D2O wurden die chemischen Gleichgewichtskonstanten der drei in diesem System auftretenden Carbamatbildungsreaktionen ermittelt. Außerdem wurde der Partialdruck von Kohlendioxid in den wässrigen Lösungen von MDEA oder Piperazin bzw. deren Mischungen bei 313 und 353 K gemessen. Das Modell zur Beschreibung des Dampf-Flüssigkeits-Gleichgewichtes wurde unter Einbeziehung der neuen experimentellen Daten überarbeitet. Das überarbeitete Modell ermöglicht die zuverlässige Beschreibung des Dampf-Flüssigkeits-Gleichgewichtes der Systeme CO2+MDEA+Wasser und CO2+Piperazin+Wasser sowohl im Hochdruck- als auch im Niederdruckbereich. Das Modell ermöglicht auch Vorhersagen für das Dampf-Flüssigkeits-Gleichgewicht des Systems CO2+MDEA+Piperazin+Wasser. Die Vorhersagen für das Dampf-Flüssigkeits-Gleichgewicht sind nicht so gut. Der Grund liegt vermutlich in der Vernachlässigung der Wechselwirkungen zwischen Piperazin- und MDEA- Spezies. In the present work the vapour-liquid equilibrium of two important systems have been considered: -the simultaneous solubility of sulfur dioxide and ammonia in aqueous salt solutions and -the solubility of carbon dioxide in aqueous solutions of 2,2´-methyliminodiethanol (N-methyldiethanolamine; MDEA) and/or piperazine. The first system is treated in many processes related to the chemical, power and oil industries (e.g., in coal gasification, in wet flue gas desulfurization, or in water washing processes of catalytic cracker overhead systems). In previous work, a thermodynamic model describing the phase equilibrium of the chemical reacting system SO2+NH3+H2O+salt (salt = (NH4)2SO4 or Na2SO4) was developed ([93], [95], [96], [98]). The model was based on phase equilibrium data of the systems a) (NH3+H2O), b) (SO2+H2O), c) (salt+H2O), d) (NH3+SO2+H2O), e) (NH3+salt+H2O), and f) (SO2+salt+H2O) for temperatures from 313 K to 373 K. The model takes into account the formation of two sulfur containing ionic species: bisulfite and sulfite. Transmission IR-spectroscopic investigations of the system SO2+NH3+H2O reported by Scott and McCarthy indicate that in those solutions pyrosulfite does not exist in significant amounts [102]. Therefore, the formation of pyrosulfite was neglected in the original development of that model. But, new results from attenuated total reflectance (ATR)-IR spectroscopic investigations presented here, reveal considerable amounts of pyrosulfite in that system. Only scarce information on the temperature dependent chemical reaction equilibrium constant for the formation of pyrosulfite in aqueous solutions is available in the literature [40]. In the present work, this chemical reaction equilibrium constant was determined for temperatures from 313 to 353 K by ATR-IR-spectroscopic and calorimetric investigations of the system Na2S2O5+H2O. The thermodynamic model for the system SO2+NH3+H2O+salt was extended using that new chemical reaction equilibrium constant for the formation of pyrosulfite as well as the enthalpy of dilution in the systems SO2+H2O, SO2+NH3+H2O and SO2+salt+H2O as determined by Meyer [70]. This new model is able to predict both the vapour-liquid equilibrium and the enthalpy of dilution for the quaternary systems. Predictions of the gas solubility in the system NH3+SO2+Na2SO4+H2O are in good agreement with the experimental results. Predictions of the vapour-liquid equilibrium in the system NH3+SO2+(NH4)SO4+H2O are not so good. Predictions of the enthalpy of dilution of the quaternary aqueous systems are in good agreement with experimental results. Aqueous MDEA solutions are widely used for the absorption of sour gases from gaseous effluents (e.g., natural gases, refinery gases and synthesis gases), especially for the selective removal of hydrogen sulfide from gases containing carbon dioxide. Process modifications attempt to improve the absorption of carbon dioxide by adding modifiers (usually primary or secondary amines) to the aqueous MDEA solution. Piperazine is a commonly used modifier. Correlating and predicting the vapour-liquid equilibrium for the simultaneous solubility of CO2 and H2S in aqueous solutions of MDEA and piperazine at first requires reliable information on the solubility of the single gases in water and in the aqueous solutions of the single amines. In addition, reliable information is required on the equilibrium constants of the interesting chemical reactions. In earlier investigations ([61], [83], [86], [122]), the solubility of the single gases carbon dioxide and hydrogen sulfide in aqueous MDEA or piperazine solutions was measured in the temperature range from 313 to 413 K, for amine molalities up to 8 mol per kilogram of water, and pressures up to about 8 MPa. In addition, the protonation constant of MDEA in aqueous solution was determined from emf-measurements (electromotive force) at temperatures from 278 to 368 K [84]. From literature no reliable data is available for three carbamate formation constants. In the present work these chemical reaction equilibrium constants were determined for temperatures from 283 to 333 K by NMR-spectroscopic investigations of the system CO2+piperazine+H2O. With this experimental data, a thermodynamic model for describing the phase equilibrium for the system CO2+H2S+MDEA+piperazine+water was developed in the previous work [86]. This model is able to predict the gas solubility in the low gas loadings region. The accuracy of this prediction could not be tested, as no sufficient experimental data are present for the comparison. Therefore, in the present work the solubility of carbon dioxide in aqueous solutions of MDEA and/or piperazine in the low loadings range was determined by means of Headspace gas chromatography. The model was extended using the new experimental data.

Based on several severe air pollution episodes, a temporal correlation between high concentrations of particulate matter (PM) and SO2 pollution and acute increases in respiratory and cardiopulmonary mortality had been established in Vienna for the 1970's. After air pollution had decreased in Austria in the 1980's--as documented by data on SO2, and total suspended particles (TSP)--no such associations between day-to-day changes of SO2 and TSP and mortality have been documented any more, however, traffic related pollutants like fine particles and NO2 remained a problem. Therefore, short term effects of PM on lung function, morbidity and mortality were investigated in Vienna, Linz, Graz and a rural control area. Long-term exposure and chronic disease--even more important for public health--were studied in repeated cross-sectional, a mixed longitudinal and a birth cohort study on school children in the city of Linz. Lung function growth was found impaired from long-term exposure to air pollutants and improved in districts where ambient air pollution had decreased. Where only TSP and SO2 had decreased, no continuous improvement of small airway function was found and end-expiratory flow rates stayed impaired where NO2-reduction from technical improvements of cars and industry was counterbalanced by increase of motorized (diesel) traffic. Remaining acute effects of ambient air pollution in 2001 from PM, NO2 and co-pollutants found in a time series study also show that continuing efforts are necessary. Active surface of particles inhaled several hours to days before spirometry was found related to short-term reductions in forced vital capacity-FVC (p0.01), forced expiratory volume in one second-FEV1 (p0.01) and maximal expiratory flow rate at 50% of vital capacity-MEF50 (p0.05). In pupils with asthma or previous airway obstruction 4-week-diaries proved that the following symptoms increased with acute exposure to higher active surface of particles: wheezing (p0.01), dyspnea, cough when going to sleep, cough at night (p0.05). Efforts to reduce exposure to fine particles from motor traffic and passive smoking have to be increased if we want to achieve full recovery of children from air pollution effects and best respiratory performance in adulthood. Surveillance seems to be necessary not only for particle mass but also for particle number and surface. Little is known on the mechanisms of irreversible long-term effects of PM such as myocardial infarction and cancer. In a prospective cohort study on 1630 dust-exposed and 1630 non dust-exposed workers matched for smoking we found an increase of lung cancer related to nonfibrous insoluble PM. Other studies were able to relate lung cancer to specific particles like those from diesel engines, and a large prospective study of the American Cancer Society was able to link lung cancer in the general population with long-term exposure to fine particles from combustion processes. All these recent epidemiological findings will have consequences for occupational and ambient air PM standards.

[no abstract]

Exposure to atmospheric pollutants may adversely effect respiratory function. Asthmatics as well as persons with airway hyperresponsiveness are more sensitive to atmospheric pollutants than normal persons. So we examined the influence of bovine serum albumin (BSA) sensitization on changes of respiratory function induced by SO2 exposure of 10 min. in non-anesthetized rabbits. Furthermore the effect of SO2-exposure on changes of respiratory function induced by secondary BSA-sensitization was tested. Respiratory flow (VR), tidal volume (Vt), respiratory pressure (PM), respiratory resistance (RL = PM/VR), and dynamic Compliance (Cdyn = Vt/PM) were examined. Our data showed that SO2-exposure marginally reduced respiratory flow and increased respiratory resistance but did not change tidal volume and dynamic compliance. Reduction of respiratory flow induced by SO2-exposure was independent from BSA-sensitization in the first week, however increase of respiratory resistance was slightly higher in BSA sensitized than in non-sensitized rabbits after SO2-treatment. Secondary BSA-sensitization reduced respiratory flow independent from SO2-inhalation and increased respiratory resistance stronger in SO2 treated than in non-treated rabbits. Tidal volume and dynamic compliance also increased after secondary sensitization. The increase of dynamic compliance was significantly higher in non-treated than in SO2 treated rabbits, but it was not so evident in case of tidal volume.

We studied the effect of sulfur dioxide (SO2) and nitrogen dioxide (NO2) on mucociliary activity (MCA) and ciliary beat frequency (CBF) in 63 guinea pig tracheas. The tracheas were placed in a gas cylinder and exposed for 30 minutes to SO2 concentrations ranging from 2.5 to 12.5 ppm or to NO2 concentrations ranging from 3.0 to 15.0 ppm. Control experiments were performed with exposure of the tracheas to synthetic air. MCA was measured by recording the light reflected from ciliated mucous membranes using an infrared barcode reader and CBF using video-interference microscopy. The exposure to 2.5 ppm SO2 caused a reduction in mean MCA of 63% and no significant changes in CBF. Higher SO2 concentrations caused a further impairment of MCA as well as a dose-dependent decrease in CBF. 10.0 or 12.5 ppm SO2 induced a decrease from baseline values to approximately 20% in MCA and to roughly 30% in mean CBF. The exposure to NO2 at concentrations ranging from 3.0 to 15.0 ppm did not induce any changes in MCA or CBF of the guinea pig tracheas. Our results show that exposure to SO2 for 30 minutes is able to depress the mucociliary clearance of guinea pig tracheas, whereas the exposure to equivalent NO2 concentrations for the same time do not alter the mucociliary transport.

Mucociliary transport is an important defense mechanism of the respiratory tract. The aim of this study was to investigate the effect of SO2 and NO2 at different concentrations on ciliary beat frequency (ZSF). Single ciliated cells were obtained from 25 volunteers by nose brush. ZSF was quantified using video-interference-microscopy. The cells were placed on a polycarbonate membrane, which was in contact with the surface of a reservoir filled with RPMI medium (bicarbonate buffered) or electrolyte solution (Ringer), allowing the cells to be supplied by capillarity. In an exposure chamber the cells were exposed for 30 to 120 min to SO2 2.5 to 15.0 ppm at 37 degrees C. SO2 induced a dose dependent decrease in ZSF of the cells, supported by Ringer solution. 2.5 ppm SO2 caused a 42.8%, 12.5 ppm a nearly 100% decrease (8.10 +/- 0.24 vs. 0.28 +/- 0.20 Hz). ZSF of cells cultured in RPMI medium was reduced moderately after 12.5 ppm SO2 exposure (7.90 +/- 0.26 vs. 6.66 +/- 0.31 Hz). In Ringer solution we observed a decrease of pH after 30 min SO2 exposure with 12.5 ppm to a minimum value of 3.6. In marked contrast, the pH of RPMI medium remained constant at 7.5 under identical conditions. After adding RPMI medium to Ringer solution, ZSF increased in parallel to the pH (5.0 ppm: 2.77 +/- 0.37 to 7.97 +/- 0.49 Hz). After an initial increase in ZSF, 120 min NO2 exposure to 15.0 ppm yielded a decrease in ZSF of 23.3% under conditions of constant pH.(ABSTRACT TRUNCATED AT 250 WORDS)

Mucus hypersecretion is an important symptom of chronic airway diseases such as Chronic Bronchitis, Asthma, and Cystic Fibrosis. The cellular and molecular pathogenesis of hypersecretion is poorly understood. Airway mucin is a marker of chronic hypersecretion. By characterising an airway mucin cDNA, we were able to show that human airway epithelium and the intestine express the same mucin gene MUC2. It is also expressed in Cystic Fibrosis tracheobronchial epithelium. In an animal model of hypersecretion, viral infection and sulfur dioxide exposition lead to a dramatic accumulation of mucin mRNA in the airway epithelium. This could represent an important initial step in the pathogenesis of tracheobronchial hypersecretion.

Sulfur dioxide (SO2) and Asbest are frequently found at workplaces. They can induce airway and lung parenchymal injury. Alveolar macrophages (AM) play an important and decisive role in the damage of respiratory tissue. We evaluated the reactive oxygen intermediates (ROI) production of AM and peripheral blood mononuclear cells after exposure with SO2 and Chrysotile B. The cells were exposed in a special gas exposure chamber at 37 degrees C and 100% air humidity for 30 minutes to 1.5 or 2.5 ppm SO2. Afterwards they were incubated for one hour with 100 micrograms or 200 micrograms Chrysotile B. Control experiments were performed with cell exposure to synthetic air without SO2 and Chrysotile B. Spontaneous and phorbol myristate acetate (PMA) stimulated ROI-release were measured by chemiluminescence and the cell toxicity was evaluated with the trypan blue exclusion test. Our results show a dose-dependent increase of the spontaneous ROI-production of AM after SO2 and Chrysotile B exposure. Exposure to 100 micrograms Chrysotile B caused an 1.5 fold, exposure to 1.5 or 2.5 ppm SO2 plus 100 micrograms Chrysotile B resulted in an 2.4 respectively 3.3 fold increase in ROI-release compared to control experiments. Exposure of AM to 200 micrograms Chrysotile B yielded an 1.9 fold, exposure to 2.5 ppm SO2 plus 200 micrograms Chrysotile B a 3.9 fold elevation in the spontaneous ROI-production compared to control experiment with standard air. A similar reaction pattern was observed in PMA-stimulated AM and in peripheral blood mononuclear cells.(ABSTRACT TRUNCATED AT 250 WORDS)

This paper describes results of ecotoxicological investigations concerning the effects of industrial pollutants on farm animals. By means of simultaneous experiments using dusts from lignite-filters and sedimentation-filters as well as sulfur dioxide (SO2) as stress models and by using studies on farm animals in pollutant-burden regions of eastern Germany it could be shown, that pollutants can lead to disorders of health, efficiency and behaviour, like o. g. heavy metals, and to contamination of food of animal origin. Dusts, resulting from combustion of lignite and SO2 initiate non specific effects in the organism and it is only difficult to determine their part on the decrease of productivity and metabolic disorder of farm animals in pollutant regions.

The Reutlingen/Tübingen/Rottenburg region in Baden-Württemberg is characterized by medium and small sized towns and rural areas. In 1986/87 875 cases of croup were registered there by the treating physicians during a 24-months period. In consideration of meteorological and virological "disturbing variables" the influence of the measured air pollution by SO2, NO, NO2, CO, ozone and dust on croup frequency was computed by means of statistical regression methods. For the months September till March, the main manifestation period of croup, weak but statistically significant influences of the daily means of NO and NO2 were found, for the whole year influences of NO, NO2, and CO. During the winter months temperature correlates positively and velocity of wind negatively, both statistically with significance, to croup frequency. The essential conditions of croup are individual and familiar disposition on the one hand, virus infections on the other. Air pollution of a concentration like given in the investigated region was found to be a weak additional factor that favours the manifestation of croup.

From 1978 to 1988 in the district of Annaberg (Saxony, state frontier to Czechoslovakia) investigations were accomplished to assess the state of health in people living there. The southern part of the district rises to a crest (Saxon Ore Mountains). It is influenced by air pollution from Northern Bohemia. The incidence of acute infections of the upper airways showed a remarkable dependence on the degree of air pollution in the age groups up to 18 years, especially in the group of infants. In the polluted area (high overload) the morbidity of infants was 7-fold in relation to the unpolluted area of the district. In the polluted area when temperature was lower than -5 degrees C the incidence of acute respiratory infections in infants closely correlated (r = 0.90) with the concentration of SO2 in ambient air. In the town Annaberg (urban air pollution) the frequency of absence of children from school caused by acute respiratory infections was elevated in relation to the rural parts of the district, but there were no differences among these rural parts. In the polluted area the severe stages of cardiorespiratory diseases were passed through with evident acceleration. In healthy adults living there the mean values for immunoglobulins of class A and class M tended to be elevated, and in school children the antibody titers against influenza A and B were increased.

The study was conducted on 29 New-Zealand female rabbits to examine the dose-response pattern of SO2 in inhaled air. A group of 14 animals was exposed to papain-aerosol (P-A) twice a week for 1 h each over 12 weeks in order to increase bronchial reactivity. A group of 9 animals received similar treatment but with saline-aerosol (NaCl-A); this group served for control. The third group of 6 animals remained untreated (K). After 12 weeks of treatment individual animals were anesthetized and the P-A and NaCl-A groups were exposed for 5 min each to different concentrations of SO2 (0.0, 1.0, 2.0, 4.0 and 9.0 mg/m3). The animals of group K were treated similarly but they were exposed 5X to synthetic air; this group served the purpose to follow the anesthesia effect on respiration and cardio-vascular system. The recovery period was 30 min between the exposures. The K-animals showed gradual decrease of lung resistance (R1). In contrast P-A and NaCl-A animals both showed a clear increase in R1 following exposure to SO2, and R1 was considerably higher in P-A than in NaCl-A animals. The maximum change in R1 was caused by exposure to 4.0 mg/m3 SO2 and it was even greater than the response produced by 9.0 mg/m3 SO2 in P-A animals. A similar pattern of response was also observed in NaCl-A animals, but the highest increase in R1 was caused by exposure to 2.0 mg/m3 SO2. From these results it can be concluded that high concentration of SO2 could have a damaging effect on sensory receptors of the tracheobronchial system.

In an industrial region respiratory morbidity of children was studied in 3 localities with different levels of air pollution within maximal permissible concentrations (average monthly SO2 0.35 mg/m3, 0.25 mg/m3 and less than 0.15 mg/m3 and correlating concentrations of CO, NO2 and particles). It was shown that acute respiratory morbidity and prevalence of recurrent bronchitis did not correlate with SO2 level and was highest in a big city. There was however a correlation with SO2 level of bronchial asthma prevalence (3.0, 2.7 and 2.1), as well as morbidity with acute bronchitis (45.1, 23.3 and 10.6) and acute obstructive bronchitis (15.0, 5.4 and 2.4)--all figures per 1,000 children. Daily acute respiratory morbidity also did not correlate with peaks of SO2 during 3 preceding days, but acute bronchitis correlated with such peaks 2 days before (r = +0.5). Passive smoking and stove heating were significantly more frequent in families of children with respiratory complaints as compared to those without such complaints. Since these differences were more pronounced in industrial towns than in rural areas, it well may be that industrial pollutants potentiate or aggravate the effect of indoor air pollution.

Based on the immission levels measured in the city of Bochum (approx. 20,000 readings), 1200 hospitalized children with pseudocroup were examined for a possible relationship between croup incidence and sulphur dioxide levels. Evaluation according to geographic location showed no statistically significant correlation between croup incidence and SO2 levels over a test period of 13 years. Only for 3 of 13 years did Spearman's rank correlation coefficient show a weakly significant positive correlation (P less than 0.05). In one test year, however, there was a statistically significant negative correlation (P less than 0.025). Evaluation of the 16-year study in terms of time-dependent relationships yielded no significant deviation of pseudocroup incidence from the expected mean value for the individual SO2 concentration ranges. Over the period of this study, there was therefore no cause-effect relationship between sulphur dioxide levels and pseudocroup incidence.

Following on from the first publication, (12) concerning the burning of plastics, another 13 chemical pure polymers were burnt in an electric oven to determine the level of solid and gaseous air pollution caused by their stackgases. All 13 polymers are highly combustible but require different burning temperatures (300-900 degrees C) in order to be burnt completely (i.e. without ashrest). With the exception of PMMA and PTFE, all plastics leave a very heavy tar- and soot deposit after burning. At the other end of the scale, burning at low temperature (300 degrees C) gives rise to high concentrations of alipathic aldehyds. The pH of the exhaust-gases, dissolved in water, is neutral to strong acid (PTFE), and will cause a severe corrosion. The nitrogen-containing polymers pollute by forming cyanides, nitrogenoxides and ammonia. PTFE gives off high concentrations of fluorid into the air. PMMA decomposes in its monomer methylmethacrylate and forms large amounts of aliphatic aldehyds. ABS and SBR cause a styrene pollution.

The Swiss Association for Environmental Research is regularly evaluating environmental research activities in Switzerland and has also tried to set priorities in this field which is important especially in a small country like Switzerland. More attention should be paid to the sectors of social and human sciences, energy, recycling and waste management, agriculture and cultivation in mountains, as well as to limits of maximum load of emissions and immissions within the field of environmental research. Dealing with immissions, one should differentiate between compounds which are already monitored and new compounds which are growing fast. In both cases occurrence, accumulation and effects have to be analyzed. In the sector of air hygiene probably the following areas are therefore the most critical: Immissions of nitrogen oxides, of specific hydrocarbons, of specific aerosols, of radioactive products and synergistic effects of several of these compounds and their interaction with natural processes.

On the basis of the data from the National Cancer Registry in the GDR an investigation was made, concerning the relationship between exposure to different levels of air pollution and lung cancer incidence. Estimates for the exposure to major factors of air pollution as sulfur dioxide, sedimentation dust and a global air index were calculated for each county of the GDR. The statistical comparison of these data with respect to the age-adjusted incidence rates of the corresponding counties for the time period 1978 to 1982 have not shown any differences neither in man nor in woman. On the other side a positive correlation to the per caput consumption of cigarettes was found.

Three atmospheric pollutants are discussed: Sulfur dioxide (SO2) acts as irritant gas on upper airways, trachea and large bronchi. Bronchoconstriction by SO2 is enhanced during work. Dose-response correlation may be observed with SO2 concentrations and bronchial hyperreactivity. Deaths and morbidity rates of patients with COPD parallel peaks of SO2 concentration such as occurred in the 1956 London smog. The mechanisms involved seem to be the same in cross sectional as in long term SO2 effects on human airways. Ozone (O3) is a major irritant pollutant. O3 penetrates deeply into the small airways, kills the macrophages and promotes infections. As peroxide it ruptures the cell membranes and thus lipogenases arise. Neutrophil leukocytes are attracted and transit into the peribronchiolar tissue, an enrichment which may be stopped in hydroxy-urea treated dogs. A marked correlation is observed between peribronchiolar tissue neutrophilia and bronchial hyperreactivity. This may even be a new pathway in the physiopathology of bronchial asthma. Lead is a constituent of exhaust particles and is easily absorbed into the blood. As in the case of drinking-water lead or otherwise absorbed lead, blood lead levels may be markedly reduced by adequate preventive measures. Diastolic and systolic blood pressures correlate significantly with the blood lead level. A further decrease would lower the incidence of myocardial infarctions, strokes and essential hypertension.

Combustion of dust is an old problem which has gained a new importance since the introduction of electric storage heaters for space heating. Physico-chemical changes caused by heating indoor dust in a model apparatus were investigated. Four dust samples of different origins were heated at three temperatures (200, 400, 600 degrees C) for three residence times (5, 15, 30 min). The higher the temperature, the higher the weight loss expressed as percentage (15 to 75%). The residence time had no effect on the loss. Three dust samples showed pH of about 7 before heated, while the fourth showed pH of about 10. After heating to 200 degrees C, the pH of one of the samples rose from 7 to 10. When heated to 400 and 600 degrees C, all the samples showed pH values between 10 and 11. The residence time had no effect. The pH of the gaseous reaction products did not show uniform pattern at 200 degrees C. At 400 degrees C, the measured pH was between 7.5 and 8.5, while at 600 degrees C no further change was observed. Changes in pH took place during the first fifteen minutes. Chemical analysis of the reaction products with help of detector tubes indicated that dust samples when heated emit carbon monoxide, carbon dioxide, oxides of nitrogen and ammonia.