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At least 19 recordsLinked to original sources
PubMed1983

[Effects of photochemical smog from a flow reactor on bacteria. I. Determination of the effects of photochemical smog on bacteria].

To measure the damage to bacteria from photochemical smog Serratia marcescens, Staphylococcus epidermidis, Micrococcus luteus and spores of Bacillus cereus have been exposed to defined gas-mixtures. A smog-simulation-chamber has been used which allowed adjustment of reproducible and longterm constant smog formations due to the flow system. Two methods have been applied to examine the bactericidal effects of the photo-chemical smog: adsorption of bacteria to membrane filters and spraying on silk threads. Smog mixtures formed by olefines (propene 4200 ppb, isobutene 3000 ppb, trans-2-butene 1600 ppb) and nitrogene oxides (500-700 ppb) showed bactericidal effects at ozone levels of 500 ppb. The survival of exposed bacteria is influenced less by gasing with 500 ppb ozone than with the smog mixture.

Air Microbiology↗
PubMed1979

[Autoradiographic investigations on the effect of city smog extract on DNA synthesis and cell cycle of mammalian cells in vitro. I. Effect of city smog extract on DNA synthesis of kidney- and embryonic cells of the golden hamster in vitro (author's transl)].

We analysed the effect of city smog extract from Düsseldorf on DNA synthesis of mammalian cells in vitro. Airborne dust was extracted with aceton and thereafter transferred to dimethylsulfoxide. Dosage was calculated according to the benzo(a)pyrene content. We used logarithmically growing cultures of hamster kidney and embryonic cells. DNA synthesis was determined autoradiographically by incorporation of 3H-Thymidine. We found that city smog extract exerted a dose-dependent cytotoxic effect leading to a decrease of DNA synthesizing cells. High concentrations of city smog extract induced cell necrosis and suppressed DNA synthesis completely. Moderate doses of extract caused a dose-dependent, but temporary cessation of DNA synthesis. Cells resumed DNA synthesis after a certain delay. Low concentrations of city smog extract induced no detectable effects. Inhibition of DNA synthesis was evident already one hour after addition of extract. Therefore a direct effect on DNA metabolism could be supposed. Furthermore, exposed cultures demonstrated a delay in entrance of new cells into the DNA synthesis. Alterations in DNA synthesis could be of great importance for carcinogenesis, especially if we take in consideration the content of carcinogens in city smog extract.

Animals↗
PubMed1979

[Autoradiographic investigations on the effect of city smog extract on DNA synthesis and cell cycle of mammalian cells in vitro. II. Alterations of the cell cycle of hamsters kidney cells and hamster embryonic cells in presence of city smog extract (author's transl)].

We used the autoradiographic method according to Quastler and Sherman to analyse alterations in the cell cycle under the influence of city smog extracts. Investigations were performed on logarithmically growing cultures of kidney and embryonic cells of the Syrian golden hamster. Low concentrations of city smog extracts (0.125 micrograms/ml Benzo(a)pyren-equivalent) induced a remarkable delay of cell entrance into DNA-synthesis. Furthermore a considerable prolongation of generation time and phase of DNA-synthesis was detected. The number of mitosis was strongly reduced. Already a doubling of concentration of city smog extract caused an almost complete breakdown of the cell cycle and a disappearing of mitosis for a time period of 10 hours. Our results strongly indicate that city smog extracts lead to a severe alteration of the molecular biology of the cell. Taking this in consideration, it can be assumed that a long term exposure of human beings to the city smog could induce an injury of health.

Air Pollutants↗
PubMed1978

[Analysis of the biological effect of city smog extract. III. Comparative investigations on the effect of city smog extracts on cell replication and DNA-synthesis of kidney cells in vitro from the primate Cercopithecus aethiops (author's transl)].

We analysed the cytotoxic effect of city smog extracts from a heavy industrialized area using kidney cell cultures from the primate Cercopithecus aethiops.--Using logarithmically growing cell cultures we determined cell replication and the rate of DNA-synthesis after incorporation of 3H-thymidine.--In presence of city smog extracts we found a dose dependent reduction of cell replication and of DNA-synthesis. In presence of high concentrations (BP-aquivalent 0.25-0.5 microgram/ml) of city smog extract we found no increase in cell number over a period of 72 h. Under the same conditions hardly any DNA-synthesis was detected.--In presence of middle and low concentrations of city smog extract a dose- and time-dependent increase in cell number and rate of DNA-synthesis was detected.

Animals↗
PubMed1979

[Analysis of the biological effect of city smog extract. V. Comparative investigations on the effect of city smog extracts on DNA synthesis of Syrian hamster kidney and embryonic cells and of African green monkey kidney cells in vitro (author's transl)].

We analysed the effect of two samples of city smog extract from Bochum and Duisburg on DNA synthesis of mammalian cells in vitro. As a test system we used tissue cultures of kidney and embryonic cells from the Syrian golden hamster and monkey kidney cells from Cercopithecus aethiops. DNA synthesis of cells was measured by autoradiography using 3H-Thymidine. Both samples of city smog extract exerted a dose-dependent decrease of the rate of DNA synthesis in tissue culture cells. These alterations of nucleic acid metabolism were expressed by a reduction of DNA-synthesizing cells and by a delay of entrance of cells in DNA synthesis. High concentrations of city smog extracts induced a large number of cell necroses. Monkey kidney cells were more sensitive to the toxic action than hamster cells. Furthermore the city smog extract from Duisburg showed a stronger toxic effect than the extract from Bochum.

Air Pollutants↗
PubMed1977

[Analysis of the biological effect of city smog extract. I. Cytotoxicity of city smog extract from an urban area and of polycyclic aromatic hydrocarbons on mouse macrophages in vitro (author's transl)].

We analyzed the cytotoxic effect of a city smog extract from a large urban area, employing mouse macrophages in vitro. In parallel experiments we tested carcinogenic and non carcinogenic polycyclic aromatic hydrocarbons: benzo(a)pyrene, 7, 12-dimethylbenzanthracene, pyrene and anthracene. City smog extract induced a dose-dependent reduction of cell viability and an alteration in cell membrane permeability. In contrast to city smog extract the carcinogenic and non carcinogenic polycyclic aromatic hydrocarbons produced no detectable cytotoxic effects in the dose range we analyzed. Possible implications of the cytotoxic effect of city smog extract on the lung are discussed.

Air Pollutants↗
PubMed1978

[Analysis of the biological effect of city smog extract. II. Effect of a city smog extract on cell growth and DNA synthesis of hamster kidney cells in vitro (author's transl)].

A city smog extract from an urban area inhibits the cell growth of hamster kidney cells in vitro. Parallel to an inhibition of cell multiplication a diminished rate of total DNA synthesis appeared. The number of cells in DNA synthesis is depressed in presence of city smog extract. These phenomena revealed a dose-response relationship. The biological effect of city smog extract is discussed.

Animals↗
PubMed1983

[Effects of photochemical smog from a flow reactor on bacteria. II. Determination of bactericidal components in photochemical smog].

The mixture of substances in the photochemical smog could be detected by different reduction rates of exposed bacteria. Beside ozone other products of the ozone/olefine-reaction could reduce the survival of exposed bacteria. For Staph. epidermidis a toxic influence from the reaction products could be found only after UV-irradiation. The main components were aldehydes, hydrocarbons, radicals, peroxiradicals and radicaloxides. For peroxiacetylnitrate (PAN) no bactericidal effect could be found for bacteria adsorbed on membrane filters in concentrations of 300 ppb in the smog (UV-irradiation was put off for two hours) and even in concentrations of 1000 ppb prepared by gaschromatography. The influence on lipopolysaccharide (lps) defective mutants of Salmonella minnesota showed the protection of the lps-layer against e.g. relative humidity and ozone (500 ppb), but no specific protection against smog components.

Air Microbiology↗
PubMed1978

[Analysis of the biological effect of city smog extract IV. Growth inhibition of kidney cell cultures (cercopithecus aethiops) under the influence of a city smog extract and its polyaromatic fractions (author's transl)].

The cell growth of exponentially growing kidney cell cultures of Cercopithecus aethiops was determined by estimation of protein content. The effect of city smog extracts and its polyaromatic fractions on cell growth was examined. Based on the benzo(a)pyren-content the crude extract of city smog exerted the strongest inhibition of cell growth, followed by non purified and purified fraction of polyaromates. The inhibition of cell growth was dose dependent. Results indicate, that for cell growth inhibition are of importance concentrations of toxic substances and exposition time.

Animals↗
PubMed1983

[Biological effect of smog extract. VII. Severe disorders of the cell cycle and its phases in kidney cultures as effected by extract and fractions of smog from a heavily industrialized area].

We analyzed the effect of airborne particulate matter, collected from the city of Duisburg on DNA-synthesis, mitotic rate and the cell cycle employing mammalian cells in vitro. As a test system we used logarithmically growing kidney cell cultures of the Syrian golden hamster (Cricetus aureatus). To elucidate alterations of DNA-synthesis and cell cycle under influence of extracts and fractions of city smog we used the autoradiographic method and the analytic procedure according to Quastler and Sherman. Extract and fractions induced a dose dependent decrease of DNA synthesizing cells, reduction of mitotic rate and very strong alterations of the cell cycle. The particular phases of the cell cycle were extended, partly abolished. We observed great differences concerning the effect of various fractions. The strongest effect was exerted by the total extract and the methanol-fraction. In this case the effective dosage was equivalent to an air volume of 2-5 cbm. With a declining sequence of toxicity followed the fractions of cyclohexane, propanol and of polyaromates. Results demonstrate that airborne particulate matter or city smog from industrialized areas contain substances which act strongly cytotoxic on mammalian cells in vitro and induce heavy alterations of the cell cycle. Therefore we have to expect, especially after long-term exposure also in human being health damages.

1-Propanol↗
PubMed1980

[Analysis of the biological effect of city smog extract. VI. Comparative investigations on the effect of city smog extracts and their fractions on DNA synthesis of hamster kidney and embryonic cells and kidney cells of the primate Cercopithecus aethiops (author's transl)].

We analyzed the effect of two samples of city smog extracts and their fractions from Duisburg on the rate of DNA synthesis of mammalian cell cultures. - We employed tissue cultures of kidney and embryonic cells from the Syrian golden hamster (Cricetus aureatus) and kidney cells from the African green monkey (Cercopithecus aethiops). The DNA synthesis was determined autoradiographically after incubation with 3H-thymidine. We found that both city smog extracts exerted a dose-dependent suppression of cellular DNA synthesis. Monkey kidney cells were more sensitive than rodent cells. Analysis of single fractions indicate that the inhibition of DNA synthesis is the result of combined effects of all fractions. At present time it is not possible to correlate the toxic effect of the complete extract special to a single fraction or compound group.

Air Pollutants↗
PubMed1985

Bactericidal effects of photochemical smog constituents produced by a flow reactor. III. Communication: determination of mutagenic effects of photochemical smog on E. coli K 12 343/113.

The multipurpose strain E. coli K12 343/113 allows the simultaneous detection of different DNA alterations such as base-pair changes, frameshifts and deletions. The investigations show the detection of mutagenic potency in the mixture which is called photochemical smog, produced by a flow reactor. Responsible for these effects were ozone and hydrocarbon-radicals, but not NOx, hydrocarbons (propene, isobutene, trans-2-butene) and peroxiacetylnitrate (PAN). In the given conditions these mutagenic substances are involved in DNA alterations like base-pair changes and deletions due to the amounts of colonies in the gal+-, MTR-, and arg+-system. No frameshifts could be detected in the nad+-system.

Acetates↗
PubMed1992

Are children with asthma affected by smog?

OBJECTIVE: To assess the relationship between atmospheric smog and emergency department attendances in children with asthma. DESIGN: The number of child attendances with acute asthma was calculated retrospectively for each day of the 1989 calendar year. Daily smog data for 1989 were then obtained from the Environment Protection Authority of Victoria, and were related statistically to asthma attendances. SETTING: The Emergency Department of the Royal Children's Hospital, Melbourne, which provides primary, secondary and tertiary level health care to the children of Victoria. PATIENTS: All children over two years of age with acute asthma. MAIN OUTCOME MEASURE: The number of attendances with asthma each day for the 1989 calendar year. RESULTS: Smog alerts (smog days predicted by the Environment Protection Authority) and smog episodes (actual smog days of all types) were not significantly related to asthma attendances. A significant relationship was noted, however, between asthma attendances and days when the airborne particulate index was above the acceptable threshold. No relationship was found between asthma attendances and ozone levels (a marker of photo-oxidant smog), or between any smog index and days of unusually high asthma attendance (asthma epidemic days). All smog variables combined explained only 2.3% of the variance in asthma attendance. CONCLUSIONS: Although the overall contribution of smog to asthma attendances in children is small, the correlation between asthma attacks and airborne particles is a hitherto unreported finding in Australia and is potentially of public health importance.

Adolescent↗
PubMed1989

Does smog increase the general practitioner's workload?

Dublin city experienced a week-long episode of intense smog in November 1988. A retrospective analysis was carried out in ten general practices of the numbers of patients seen during November. Each practice was situated in an area affected by high smog levels. The numbers of patients seen in surgery and on house-calls showed no differences during the weeks preceding the smog outbreak, during the period of high smog levels or during the week after this period. No qualitative data on the reasons for patients' visits were collected and no comments can be made on the nature of patients' illnesses during this period. There was no evidence for an increased workload in general practice caused by this episode of intense smog but a prospective study is necessary to confirm this finding and to examine the nature of patients' problems during such an episode.

Humans↗
PubMed1984

[Biological effects of smog. VIII. Impulse cytophotometric cell cycle analysis of synchronized Syrian hamster kidney cell cultures (line 14-b)].

Syrian hamster kidney cultures of line 14-1b were synchronized by excess of thymidine. Thereafter in the phase of DNA synthesis cell cultures were exposed to extract and fractions of city smog, derived from a polluted area at the river Rhine and Ruhr. Using impulscytophotometry and estimation of mitotic frequency cell cycle analyses were conducted on synchronized exposed and control cultures. The total extract obtained by methanol treatment of city smog was further fractionated by organic solvents leading to fractions of cyclohexane, polyaromates and propanol. Cell cycle progression of synchronized cultures was inhibited in a dose dependent manner by increasing concentration of city smog extract and its fractions. This inhibition led to a prolongation of DNA synthetic phase and to an accumulation of cells in G2(+ M)-phase. The total cell cycle showed a prolongation of 3-5 h. The strongest effect was induced by the total extract. We have to emphasize that already amounts of city smog which were found in air volumes of 2-5 m3 exerted strong effects. With a declining sequence of toxicity followed the fractions of cyclohexane, propanol and of polyaromates. Our results show, that samples of city smog from polluted areas contain substances which induce heavy alterations in cell cycle progression of mammalian cells in vitro. These highly effective toxic substances are dangerous for human health, especially after a long-time exposition.

1-Propanol↗
PubMed1994

Trends in photochemical smog in the Cape Peninsula and the implications for health.

There has been growing public concern over reports of increasing air pollution in the Cape Peninsula. Attention has been focused on the 'brown haze' and on photochemical smog. Because of deficiencies in the monitoring equipment, information on trends in photochemical smog levels over the past decade is limited. Trends in oxides of nitrogen, one of the main precursors of photochemical smog, and therefore an indicator of the potential for its formation, were examined for the period 1984-1993. Meaningful data for determining trends were available from only a single site. Increases in mean monthly levels, peak hourly levels and the number of times guidelines were exceeded were demonstrated. Given the dynamics of formation of photochemical smog and the particular role of motor vehicles, it is argued that the trends measured at this site are probably an underestimate of the trends in other parts of the Cape Town metropolitan area. Some of the precursors of photochemical smog, notably nitrogen dioxide, and some of its components, notably ozone, have been shown to be detrimental to respiratory health at levels close to, or below, current recommended guidelines. A continuing increase in these pollutants will therefore result in more respiratory illness, particularly among susceptible groups. This calls for an upgrading of monitoring of air pollution in Cape Town and for appropriate steps to prevent its further increase.

Air Pollutants↗