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PubMed1983

[Importance of atmospheric air pollution in the development of diseases].

Our knowledge on the effects of air pollution to health goes back up to antiquity. Industrialization with its consequences has multiplied the problem, the effects of air pollution to the lungs gaining special significance. The research of the relations is intricate because no simple dose-response relations are existing between environmental influence and population. The great number of harmful factors and of their changing concentration is faced the different susceptibility of the population and the range of response within different population groups and, finally, the multifactorial pathogenesis of chronic diseases, mentioned for assessing the hazards of air pollution. There is distinguished between local and systemic effects of air pollution to the respiratory tract. Chronic respiratory diseases and bronchial carcinoma are discussed as local effects whereas poisonings by carbon monoxide, lead and cadmium (over the human air tract) represent systemic effects.

Air Pollutants↗
PubMed1995

[Time series analysis in environmental epidemiology: short-term effects of air pollution on mortality and morbidity].

This work gives an overview of design and analysis of temporal studies using aggregated data in air pollution epidemiology. In the last years time series are often used to study the short-term association between ambient air pollution levels and aggregated health data. Health endpoints are usually daily mortality and/or daily hospital admission data from routine health registers. Air quality data are commonly obtained from one (or a few) fixed site monitoring stations. To detect the temporal association between the time-pattern in air pollution and the time-pattern in health data particular attention needs to be given to the autocorrelation structure, to the seasonality and long term trend in the data, and to the weather variables. Poisson regression with autocorrelated residuals is the suitable statistical method to analyze time studies. Furthermore, the pollutant variable can be analyzed at different lag-times to account for short latency periods in the manifestation of diseases. Studies with temporal aggregated data show the same disadvantages of the ecologic studies, although, in this case, confounding is less of a problem. Temporal studies usually are based on a large database, so that sufficient power can be achieved to detect even weak associations. Finally, the exposure information on subjects is often better characterized by short-term fluctuations in ambient air quality than is the case in geographic aggregations.

Air Pollutants↗
PubMed1993

[The effect of air pollution on the allergic reactivity of the population].

An epidemiological study was carried out in several regions in Bulgaria polluted by industry and motor vehicle transport. The investigation included monitoring of ambient air pollution, a questionnaire study of 13040 persons, and allergological/immunological testing of representative groups of population. The testing was performed on persons selected by the questionnaire study, who were not exposed professionally to toxicants. The ambient air was contaminated by particulates and gaseous contaminants in the majority of the studies areas. The questionnaire study revealed an increased incidence of complaints indicative of allergic reactions, such as recurring skin eruptions, allergic rhinitis, conjunctivitis, asthmatic bronchitis. The positive skin tests were twice as common among the residents of polluted areas as compared to control. A decreased activity of the complement and increased levels of immunoglobulins (IgG, IgA, IgM) were found in the exposed population. The changes found in the study suggest a health risk for the population created by air pollution.

Adult↗
PubMed1994

Health effects of outdoor air pollution.

One hundred sixty-four million Americans live in areas that fail to meet the National Ambient Air Quality Standards for six common air pollutants: particulates, sulfur dioxide, carbon monoxide, nitrogen dioxide, ozone and lead. The impact of these pollutants on health is significant. A Pollutant Standards Index (PSI) ranging from 0 to 500 is used to monitor air quality. When the PSI exceeds 100, the acceptable federal standard has been exceeded by at least one of four measured pollutants. When this occurs, all individuals should be advised to curtail physical activity between late morning and sunset and to remain indoors if possible. Athletes should be encouraged to train in the early morning, when photochemicals are usually at their lowest levels.

Air Pollutants↗
PubMed1993

[Urban atmospheric pollution and mortality: analysis of epidemiological studies published between 1980 and 1991].

This paper analyses 14 epidemiologic investigations (published from January 1980 to September 1991) about the relationship between urban air pollution and mortality. Air pollution indicators and mortality indicators are examined. Methods to analyse the relationships between these two kinds of indicators are classified according as they bring "qualitative information" trying to answer the question: "is there any relationship between air pollution and mortality?" or according as they try to quantify this relationship. Results are presented by author. Confounding factors and means to take them into account are described. This paper ends by a discussion about interest and limits of these studies. It emphasizes the importance of the collaboration between metrologists of urban air pollution and epidemiologists.

Air Pollutants↗
PubMed1997

Damage to the nasopharyngeal mucosa induced by current levels of urban air pollution: a field study in lambs.

This study concerns the effects of urban air pollution on the nasopharyngeal epithelium, with the aim of evaluating the possible harmful activity of levels of atmospheric pollution which are not currently considered to be dangerous. Over a 3 month period, 10 lambs kept in a zone characterized by numerous vehicles were sacrificed at regular intervals, and their nasopharyngeal mucosa was examined by scanning electron microscopy and image analysis. Two lambs kept in a rural area were used as controls. The local levels of some airborne contaminants (NO(x), NO2, NO, SO2, CO and particulate matter with aerodynamic diameter < or =10 microm (PM10)) were monitored throughout the experiment. The urban air had an irritating effect, inducing hypersecretion of mucus and morphological damage to the ciliated epithelium. These alterations increased with the duration of exposure to urban air and with increasing pollution levels, although the levels remained below current legal levels. We conclude that the harmful effects of airborne contaminants are probably underestimated. Moreover, physicochemical evaluation of pollution parameters should be complemented by morphological study of upper respiratory epithelium in exposed animals, since this mucosa is a sensitive target for irritating agents.

Air Pollutants↗
PubMedDate not supplied

[The characteristics of the air pollution of an industrial region].

A comprehensive hygienic evaluation was done of the ambient air pollution in urban industrial centers of the Dnepropetrovsk Province. Substantiated as priority pollutants were nitrogen dioxide, formaldehyde and benz(a)-pyren. Air pollution was at its greatest in Krivoi Rog and Dneprodzerzhinsk, with the aggregated atmospheric air pollution index being 34,9 and 34,5 respectively. The chief metals in the air were found to be lead, cadmium, manganese and copper. The results obtained served as a scientific justification for a block of ecologohygienic monitoring of the region.

Air Pollutants, Occupational↗
PubMedDate not supplied

The effect of the urban ambient air pollution mix on daily mortality rates in 11 Canadian cities.

OBJECTIVE: Determine the risk of premature mortality due to the urban ambient air pollution mix in Canada. METHODS: The number of daily deaths for non-accidental causes were obtained in 11 cities from 1980 to 1991 and linked to concentrations of ambient gaseous air pollutants using relative risk regression models for longitudinal count data. RESULTS: Nitrogen dioxide had the largest effect on mortality with a 4.1% increased risk (p < 0.01), followed by ozone at 1.8% (p < 0.01), sulphur dioxide at 1.4% (p < 0.01), and carbon monoxide at 0.9% (p = 0.04) in multiple pollutant regression models. A 0.4% reduction in premature mortality was attributed to achieving a sulphur content of gasoline of 30 ppm in five Canadian cities, a risk reduction 12 times greater than previously reported. CONCLUSIONS: Ambient air pollution generated from the burning of fossil fuels is a risk factor for premature mortality in 11 Canadian cities.

Air Pollutants↗
PubMed1997

[Respiratory tract symptoms in school children exposed to indoor and outdoor air pollution].

The epidemiologic study has been carried out in 1129 nine-year old schoolchildren in 4 city areas of Krakow, which differed in air pollution levels. Indoor air quality was assessed by the presence of the environmental tobacco smoke, type of domestic heating and the presence of molds or dampness on the walls. The occurrence of two or more respiratory symptoms (chronic cough, chronic phlegm, wheezing, dyspnea attacks, breathlessness or hay fever) was associated significantly with the outdoor air pollution score (chi 2 for trend = 13.315, df:1, p = .0000), with molds/dampness on the walls (OR = 2.16, 95% CI: 1.45-3.22) and allergy in children (OR = 5.94, 95% CI: 4.12-8.59). Since the results have shown the significant relationship between allergy and outdoor air pollution as well, the study confirms that outdoor pollutants increase the risk of allergic sensitization of young children.

Air Pollution↗
PubMed1999

Effects of ambient air pollution on nonelderly asthma hospital admissions in Seattle, Washington, 1987-1994.

As part of the Clean Air Act, Congress has directed EPA to set air quality standards to protect sensitive population groups from air pollutants in the ambient environment. People with asthma represent one such group. We undertook a study of the relation between measured ambient air pollutants in Seattle and nonelderly hospital admissions with a principal diagnosis of asthma. We regressed daily hospital admissions to local hospitals for area residents from 1987 through 1994 on particulate matter less than 10 and 2.5 microm in aerodynamic diameter (PM10 and PM2.5, respectively); coarse particulate mass; sulfur dioxide (SO2); ozone (O3); and carbon monoxide (CO) in a Poisson regression model with control for time trends, seasonal variations, and temperature-related weather effects. With the exception of seasonally monitored O3, we supplemented incomplete pollutant measures in a multiple imputation model to create a complete time series of exposure measures. We found an estimated 4-5% increase in the rate of asthma hospital admissions associated with an interquartile range change in PM (19 microg/m3 PM(10),11.8 microg/m3 PM2.5, and 9.3 microg/m3 coarse particulate mass) lagged 1 day; relative rates were as follows: for PM10, 1.05 [95% confidence interval (CI) = 1.02-1.08]; for PM2.5, 1.04 (95% CI = 1.02-1.07); and for coarse particulate mass, 1.04 (95% CI = 1.01-1.07). In single-pollutant models we also found that a 6% increase in the rate of admission was associated with an interquartile range change in CO (interquartile range, 924 parts per billion; 95% CI = 1.03-1.09) at a lag of 3 days and an interquartile range change in O3 (interquartile range, 20 parts per billion; 95% CI = 1.02-1.11) at a lag of 2 days. We did not observe an association for SO2. We found PM and CO to be jointly associated with asthma admissions. We estimated the highest increase in risk in the spring and fall seasons.

Adult↗
PubMed1997

DNA damage in nasal respiratory epithelium from children exposed to urban pollution.

The nasal cavity is the most common portal of entry to the human body and a well-known target site for a wide range of air pollutants and chemically induced toxicity and carcinogenicity. DNA single-strand breaks (SSB) can be used as a biomarker of oxidant exposure and as an indicator of the carcinogenicity and mutagenicity of a substance. We examined the utility of using the alkaline single cell gel electrophoresis assay (SCGE) for measuring DNA damage in children's nasal epithelium exposed to air pollutants. We studied 148 children, ages 6-12, including 19 control children from a low polluted Pacific port and 129 children from Southwest Metropolitan Mexico City, an urban polluted area with high ozone concentrations year-round. Three sets of two nasal biopsies were taken in a 3-month period. All exposed children had upper respiratory symptoms and DNA damage in their nasal cells. Eleven- and twelve-year-olds had the most DNA damage, and more than 30% of children aged 9-12 exhibited patchy areas of squamous metaplasia over high-flow nasal regions. These areas had the greatest numbers of damaged DNA cells (P < or = 0.001) and a large number of DNA tails > 80 microns (P < 0.001) when compared to the contralateral macroscopically normal site in the same child. The youngest children with significantly less outdoor exposure displayed patchy areas of goblet cell hyperplasia and had the least DNA damage. These findings suggest that SCGE can be used to monitor DNA damage in children's nasal epithelium and, further, the identification of DNA damage in nasal proliferative epithelium could be regarded as a sentinel lesion, most likely due to severe and sustained cell injury.

Air Pollution↗
PubMed1999

Electrophoretic monitoring of pollutants: effect of cations and organic compounds on protein interactions monitored by native gel electrophoresis.

We describe how the interaction between actin and its protein ligands can be used to evaluate the presence of certain metal (Cd, Cu, Hg, Zn) ions and organic compounds (2,4-dioxin or Picloram) which are common components of environmental pollution. The assay detects the high-affinity binding of actin to actin-binding proteins (ABPs), cofilin or DNase I. The actin-ABP complex was analyzed using native polyacrylamide gel electrophoresis and quantified by scanning densitometry. These proteins are widely distributed in animals and plant cells. The assay involves allowing the proteins to form an actin-ABP complex into which increasing amounts of pollutants are titrated. Thus, the assay directly tests for inhibition of protein-protein interaction. It is sensitive to common pollutants using concentration ranges over which they are known to exert a biological toxicity. A convenient feature of the assay is the fact that all the proteins can be stored in freeze-dried form, and can be purchased commercially. We suggest that if this molecular assay is sensitive to a wide range of environmental pollutants, it could be used as a rapid and convenient assay of the environment in combination with currently available tests.

Actin Depolymerizing Factors↗
PubMedDate not supplied

Mechanism of charged pollutants removal in an ion exchange membrane bioreactor: drinking water denitrification.

The mechanism of anionic pollutant removal in an ion exchange membrane bioreactor (IEMB) was studied for drinking water denitrification. This hybrid process combines continuous ion exchange transport (Donnan dialysis) of nitrate and its simultaneous bioreduction to gaseous nitrogen. A nonporous mono-anion permselective membrane precludes direct contact between the polluted water and the denitrifying culture and prevents secondary pollution of the treated water with dissolved nutrients and metabolic products. Complete denitrification may be achieved without accumulation of NO3(-) and NO2(-) ions in the biocompartment. Focus was given to the effect of the concentration of co-ions, counterions, and ethanol on the IEMB performance. The nitrate overall mass transfer coefficient in this hybrid process was found to be 2.8 times higher compared to that in a pure Donnan dialysis process without denitrification. Furthermore, by adjusting the ratio of co-ions between the biocompartment and the polluted water compartment, the magnitude and direction of each individual anion flux can be easily regulated, allowing for flexible process operation and control. Synthetic groundwater containing 135-350 mg NO3(-) L(-1) was treated in the IEMB system. A surface denitrification rate of 33 g NO3(-) per square meter of membrane per day was obtained at a nitrate loading rate of 360 g NO3(-) m(-3)d(-1), resulting in a nitrate removal efficiency of 85%.

Bioreactors↗
PubMed2000

Biomonitoring the human population exposed to pollution from the oil fires in Kuwait: analysis of placental tissue using (32)P-postlabeling.

The placenta is a readily available source of material for molecular epidemiological investigations. As such, DNA damage in this tissue can be indicative of maternal exposure to environmental pollutants such as polycyclic aromatic hydrocarbons (PAHs). Previous reports have demonstrated that (32)P-postlabeling (PPL) is able to detect the presence of aromatic adducts in human placenta that are associated with maternal smoking during pregnancy. Using PPL we have assayed the DNA damage in placental samples from Kuwaiti mothers who were exposed to environmental pollution during pregnancy. This pollution arose in the aftermath of the Iraqi invasion of Kuwait, which left hundreds of oil wells burning. For comparison, further Kuwaiti samples were obtained approximately 1 year after the oil well fires and, as such, are from individuals unexposed to the airborne pollution from the oil well fires during pregnancy. In addition, placental samples were obtained from subjects in the United Kingdom. Adduct levels were measured in all samples using both the nuclease P1 and butanol extraction enhancement procedures. No elevation of adduct levels was observed in the placenta of mothers exposed to the oil well fires (n = 40) with either procedure (144 +/- 30 attomol/microg DNA for nuclease P1 enrichment, 245 +/- 50 attomol/microg DNA for butanol extraction), when compared with the nonexposed Kuwaiti mothers (180 +/- 32 and 281 +/- 39 attomol/microg DNA, respectively, n = 24). Similar adduct levels were observed in UK mothers who smoked cigarettes (178 +/- 30 and 284 +/- 52 attomol/microg DNA, n = 30), which in turn were approximately twice those observed in nonsmoking mothers (90 +/- 14 and 141 +/- 15 attomol/microg DNA, n = 12), although there is no significant difference in the distribution of adduct levels when statistical analysis is performed. Comprehensive interpretation of the Kuwaiti data is difficult as precise information on PAH levels is unavailable, although the data do seem to indicate that exposure to PAHs was not biologically significant.

Air Pollutants↗
PubMedDate not supplied

Influence of air pollution on chronic obstructive respiratory diseases: comparison between city (Rome) and hillcountry environments and climates.

Chronic Obstructive Pulmonary Diseases (COPDs) constitute a social problem of widespread interest. These diseases increase slowly and constantly. Air pollution and its impact on public health continually repropose certain absolute priorities, such as the pin-pointing of strategies to control the pollution sources, the planning of observational studies and the epidemic control. This work shows that a climate marked by always windy weather and low humidity and with low chemical pollutant concentrations (Pietracupa; Molise, Italy) is connected to smaller prevalence of COPDs in comparison with big cities like Rome. Living in non-polluted areas, the benefits of a healthy climate in terms of an improvement in breathing and bronchial hyperactivity reduction, may only in part be backed up by epidemic evidence; however, they are a solid base on which to build definite research projects which can effectively validate it even from an experimental point of view supported by statistics.

Air Pollutants↗
PubMed2003

Mutagenic activation of arylamines by subcellular fractions of Chamaelea gallina clams exposed to environmental pollutants.

Biochemical measurements in the sentinel clam Chamaelea gallina have been used as biomarkers of marine pollution. In this study, S9, cytosolic fractions (CF), and microsomal fractions (MF) prepared from unexposed clams and clams exposed to model pollutants were used to activate 2-aminoanthracene (2-AA) and 2-acetylaminofluorene (AAF) to mutagens in Salmonella typhimurium strain BA149, which overexpresses O-acetyltransferase. Arylamine activation was similar with subcellular fractions from unexposed and Aroclor 1254-exposed clams, but decreased with fractions from As(III)- and Cu(II)-exposed clams. Bioactivation of arylamines by CF was higher than by MF, and higher with NADH than with NADPH as the reducing agent. alpha-Naphthoflavone inhibited AAF activation by CF and MF, but increased 2-AA activation nearly twofold. In contrast to the results with arylamine activation, benzo[a]pyrene hydroxylase (BPH) activity increased twofold in fractions from Aroclor 1254- and Cu(II)-exposed clams. Activation of 2-AA was also evaluated using S9 fractions from clams sampled at littoral sites with different pollutant levels. Compared to a reference site, lower 2-AA bioactivation and higher BPH activity were found in clams containing high levels of copper and organic contaminants, although the differences were not statistically significant. While these findings agree with the results of the model Cu(II) exposure, the effects of other pollutants cannot be ruled out. The results of the study demonstrate that arylamine activation by clams is not preferentially catalyzed by microsomal monooxygenases but by unknown cytosolic system(s), and that bioactivation of 2-AA and AAF appears to occur by different pathways.

2-Acetylaminofluorene↗
PubMed1979

Mutagens in a river heavily polluted with paper recycling wastes: results of field and laboratory mutagen assays.

Paper recycling industries generate considerable quantities of waterborne wastes, and thus water pollution constitutes the greatest environmental problem associated with this industrial activity [Hunt and Franklin, 1973]. Generally the impact of this water pollution is considered in terms of aesthetic blight and deterioration of water quality. We present data that document another aspect of this pollution, the environmental contamination of an aquatic ecosystem with mutagenic materials. A natural population of the fern Osmunda regalis growing in a river heavily polluted with paper recycling wastes had a high incidence of chromosome mutations. This population was monitored for four years for the frequency of two-break chromosome mutations. These mutations were postzygotic in origin and suggested the presence of mutagens in the river water. The fern population is downstream from the outfalls of a paper recycling mill, which was discharging 13.3 X 10(6) liters of untreated paper recycling waste per day. In 1977 a waste-water-treatment facility was constructed to remove the solid waste previously discharged into the river. This facility generates 69,300 kg of solid waste daily, which is taken to a landfill. Periodic samples of this solid waste were collected from the waste-treatment facility in the summer of 1978, extracted with various solvents, and the extracts tested for mutagenic activity with the Salmonella/mammalian microsome mutagenicity test [Ames et al, 1975]. A majority of the solid waste samples contained mutagenic materials, but in all cases S-9 activation was required for mutagenic activity. The samples also were assayed with the soybean mitotic crossing-over assay [Vig, 1975]. Four out of six samples were positive. These results document the presence of mutagens in the solid waste generated by a paper recycling industry and the genetic impact of these mutagens on the local biota.

Chromosome Aberrations↗