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At least 1,639 records · Page 91Linked to original sources
PubMed2005

Peroxisomal proteomics, a new tool for risk assessment of peroxisome proliferating pollutants in the marine environment.

In an attempt to improve the detection of peroxisome proliferation as a biomarker in environmental pollution assessment, we have applied a novel approach based on peroxisomal proteomics. Peroxisomal proteins from digestive glands of mussels Mytilus galloprovincialis were analyzed using 2-DE and MS. We have generated a reference 2-DE map from samples obtained in a well-studied reference area and compared this with peroxisomal proteomes from other sequenced genomes. In addition, by comparing 2-DE maps from control samples with samples obtained in a polluted area, we have characterized the peroxisome proliferation expression pattern associated with exposure to a polluted environment. Over 100 spots were reproducibly resolved per 2-DE map; 55 differentially expressed spots were quantitatively detected and analyzed, and 14 of these showed an increase in protein expression of more than fourfold. Epoxide hydrolase, peroxisomal antioxidant enzyme, and sarcosine oxidase (SOX) have been identified by ESI MS/MS, and acyl-CoA oxidase, multifunctional protein, and Cu,Zn-superoxide dismutase were immunolocalized by Western blotting. Our results indicate that a peroxisomal protein pattern associated to marine pollutant exposure can be generated, and this approach may have a greater potential as biomarker than traditional, single-protein markers.

Animals↗
PubMed2005

A three-level model for binary time-series data: the effects of air pollution on school absences in the Southern California Children's Health Study.

A three-level model is proposed to simultaneously examine the effects of daily exposure to air pollution and individual risk factors on health outcomes without aggregating over subjects or time. We used a logistic transition model with random effects to take into account heterogeneity and overdispersion of the observations. A distributed lag structure for pollution has been included, assuming that the event on day t for a subject depends on the levels of air pollution for several preceding days. We illustrate this proposed model via detailed analysis of the effect of air pollution on school absenteeism based on data from the Southern California Children's Health Study.

Absenteeism↗
PubMed2006

Cumulative effects of air pollution on public health.

Cumulative effect is an important way through which the pollutants affect public health. However, few existing dynamical models are well enough understood and documented to detect or quantify the cumulative effects and to answer pertinent questions posed by the World Health Organization (WHO): 'Is there a threshold below which no effects of the pollutants on health are expected to occur in all people?' and 'What averaging period (time pattern) is the most relevant from the point of view of health?'. Using a new semi-parametric time series modelling approach, which incorporates non-linearity and latent cumulative variables, we show that the cumulative effects on health due to continual exposure to environmental pollutants can be very serious even at levels below the national ambient air quality standards of America (NAAQS). The situation is especially worrying for chronic sufferers. Our study suggests that different pollutants may require different cumulative periods (on average) to impact on health but they share a similar functional form in respect of their impact. We also suggest some possible revision of the ambient air quality standards.

Air Pollution↗
PubMed2000

Activation of transcription factors in zebrafish cell cultures by environmental pollutants.

Many classes of environmental pollutants are found at significant levels in the aquatic environment. We are designing a fish model as an inexpensive and efficient system for the assessment of aquatic pollution. Three classes of environmental pollutants-halogenated and nonhalogenated aromatic hydrocarbons, heavy metals, and potent electrophiles-are known to upregulate particular mammalian genes via the activation of specific DNA motifs called aromatic hydrocarbon (AHREs), heavy metal (MREs), and electrophile (EPREs) response elements, respectively. We have made plasmid constructs, using these mammalian or trout response elements to drive the luciferase reporter gene. Here we show that transient transfection of the zebrafish ZEM2S cell line with these reporter constructs imparts dose-dependent gene induction upon exposure to a variety of chemicals within each of these three classes of inducers: [a] (AHRE-mediated) 2,3,7,8-tetrachlorodibenzo-p-dioxin, 3-methylcholanthrene, 3,4,5,3',4',5'-hexabromobiphenyl, Aroclor 1254, and benzo[a]pyrene; [b] (MRE-mediated) Cd(2+), Zn(2+), Hg(2+), and Al(3+); and [c] (EPRE-mediated) tert-butylhydroquinone, Hg(2+), Pb(2+), As(3+), Cu(2+), and Cd(2+). As expected, some agents gave a response to only one of the three classes, whereas others gave a mixed (AHRE- plus EPRE-mediated or MRE- plus EPRE-mediated) response. In response to several environmental agents, we found that differences in the electrophoretic mobility shift assay, using the AHRE or MRE as probe, were consistent with the degree of transcriptional activation seen with the reporter constructs. Our data suggest that these reporter constructs might be valuable for the generation of transgenic zebrafish in order to carry out mechanistic and developmental studies of transcriptional activation by environmental contaminants; moreover, such transgenic zebrafish lines might be useful as a sentinel for assessing aquatic pollution.

Animals↗
PubMed1996

Impact of point and nonpoint source pollution on pore waters of two Chesapeake Bay tributaries.

Chesapeake Bay and its tributaries are contaminated by industrial and municipal point sources and agricultural nonpoint sources of pollution. The objective of this study was to compare the porewater characteristics of two Chesapeake Bay tributaries: Wicomico River (WR) contaminated by point source and Pocomoke River (PR) contaminated by both point and nonpoint sources of pollution. Four study sites (1 mile before, adjacent to, and 1 and 2 miles after the sewage treatment plant) were chosen to collect sediment samples in both the rivers. The sediment-pore waters were analyzed for toxicity using Microtox marine luminescent bacteria-Vibrio fischeri. USEPA toxicity identification evaluation tests on these pore waters confirmed that the contaminants (ammonia and heavy metals) in WR were from municipal point sources, whereas in PR the contamination (metals, pesticides, and PCBs) was from nonpoint sources (agriculture) of pollution. The toxicity (and the concentration of contaminants) decreased both upstream and downstream from the most polluted site in both the rivers.

Analysis of Variance↗
PubMedDate not supplied

Brown trout as biomonitor of heavy metal pollution: effect of age on the reliability of the assessment.

Brown trout (Salmo trutta L.) is a native fish of the rivers of northern Spain. It is the dominant fish species in these rivers, and it is widespread over all the range of freshwater ecosystems in the area, including ecosystems potentially polluted with heavy metals. In this study, the potential of brown trout as biomonitor of heavy metal pollution and the effect of fish age on the reliability of the assessment are analyzed. Copper, lead, and cadmium concentrations of both abiotic compartments (water and sediments) and brown trout (S. trutta) from three northern Spanish rivers were analyzed. Significant correlations were found between sediment lead content and lead concentration in trout liver. One-year-old juvenile trouts were demonstrated to be useful as a biomonitor of copper and lead pollution, revealing between-location differences. Older trouts do not seem adequate to properly monitor heavy metal pollution. The effect of aging on the reliability of this species as biomonitor is discussed.

Aging↗
PubMed2000

Screening of organophosphate insecticide pollution in water by using Daphnia magna.

A simple and rapid screening method using Daphnia magna Straus (water fleas) on the basis of their immobilization was developed for detecting pesticide pollution. The laboratory testing of the toxicity of 11 organophosphate insecticides to D. magna determined 50% inhibition concentration of mobility at 48 h of exposure (48-h EC50) of 0.19 to 2.6 microg/L. The mobility of D. magna was inhibited in several river and stream waters sampled from May 1995 to February 1998 in Tokyo. Chemical analysis of the waters revealed that they were polluted by sub-ppb or ppb level of organophosphate insecticides. A significant relationship was observed between the immobilization of D. magna and the pollution level of the river and stream waters. The D. magna test could be used as a low-cost preliminary screening method for insecticide pollution.

Animals↗
PubMed2001

Metallothionein as bioindicator of freshwater metal pollution: European eel and brown trout.

The aim of this work was to evaluate the potential of metallothionein (MT) as a bioindicator of heavy metal pollution in brown trout and European eel in the field situation. River Ferrerias (North Spain) provided a good gradient of metal contamination: concentrations of heavy metals were elevated both in water and in sediments at the downstream (polluted) site and were low at the upstream (unpolluted) site. MT levels of brown trout exhibited statistically significant differences between sites. Although European eel at the polluted site had a higher MT content, differences were not significant. It is concluded that MT is a good bioindicator of heavy metal pollution in brown trout.

Anguilla↗
PubMed1999

Air pollution and respiratory drug sales in the City of Le Havre, France, 1993-1996.

The aim of this study is to evaluate ambulatory respiratory drug sales data as health indicators for the short-term effects of ambient air pollution in the city of Le Havre. Daily respiratory drug sales data were crossed with daily ambient air concentrations of sulfur dioxide (SO2), nitrogen dioxide (NO2), and black smoke (BS) using an autoregressive Poisson regression model adjusting for time trends, seasonal variations, influenza epidemics, and weather. Relative risks (RR) were expressed for an increase of two standard deviations above the mean of each pollutant. Respiratory drug sales were associated with most pollutants studied with lags varying from 1 to 9 days. For daily mean concentrations of BS, RR = 1.037 (95% confidence interval (CI) 1.009-1.066) for lag 1 and RR = 1.052 (95% CI 1.023-1.081) for lag 8. For daily mean concentrations of N02, RR = 1.033 (95% CI 1.001-1.066) for lag 1 and RR = 1.046 (95% CI 1.014-1.079) for lag 8. RR observed with a daily 1 h maximum of SO2 were RR= 1.027 (95% CI 1.004-1.051) for lag 3 and RR= 1.032 (95% CI 1.009-1.056) for lag 9. Our study concludes that ambulatory respiratory drug sales data could be useful for epidemiological surveillance of air pollutant health effects.

Air Pollution↗
PubMed2000

Air pollution and daily mortality in seven major cities of Korea, 1991-1997.

The relationship between ambient air pollution and daily mortality in seven major cities of Korea for the period 1991-1997 was examined. These cities account for half of the Korean population (about 22 million). The observed concentrations of sulfur dioxide (SO(2), mean=23.3 ppb), ozone (O(3), mean=23.7 ppb), and total suspended particulates (TSP, mean=77.9 microg/m(3)) during the study period were at levels below Korea's current ambient air quality standards. Generalized additive models were applied to allow for the highly flexible fitting of seasonal and long-term time trends in air pollution as well as nonlinear associations with weather variables, such as air temperature and relative humidity. In city-specific analyses, an increase of 50 ppb of SO(2) corresponded to 1-12% more deaths, given constant weather conditions. The risk of all-cause mortality was estimated to increase by 0.5-4%, with an increase in the 2-day moving average of TSP levels equal to 100 microg/m(3). In multipollutant models with pooled data, we found that the estimated risk of death by SO(2) was notably unaffected by adding the other two pollutants (TSP and O(3)) to the model and was statistically significant in various regression models. The rate ratio (RR) for SO(2) remained elevated, indicating an excess mortality of 3% 50 ppb (RR=1.03; 95% CI, 1.01-1.05). TSP's effect on mortality maintained its significance with O(3), but not with SO(2). This implies that there may be collinearity problems where TSP and SO(2) are included in the same model or that TSP may function less than SO(2) as a surrogate for fine particles in the ambient air of Korea. In conclusion, increased mortality was associated with air pollution at SO(2) levels below the current recommendation for air quality. Further research is needed to clarify the relationship between SO(2) and fine particles in Korea.

Adolescent↗
PubMed2001

The association between daily mortality and ambient air particle pollution in Montreal, Quebec. 2. Cause-specific mortality.

This study was undertaken to determine whether variations in concentrations of particulates in the ambient air of Montreal, Quebec, during the period 1984 to 1993, were associated with daily variations in cause-specific daily mortality. Fixed-site air pollution monitors in Montreal provided daily mean levels of various measures of particles and gaseous pollutants. Total sulfate was also measured daily (1986-1993) at a monitoring station 150 km southeast of the city (Sutton, Quebec). We used coefficient of haze (COH), extinction coefficient, and sulfate from the Sutton station to predict fine particles and sulfate from fine particles for days that were missing. We estimated associations between cause-specific mortality and PM(2.5), PM(10), predicted fine particles and fine sulfate particles, total suspended particles, coefficient of haze, extinction coefficient, and total sulfate measured at the Sutton station. We selected a set of underlying causes of death, as recorded on the death certificates, as the endpoint and then regressed the logarithm of daily counts of cause-specific mortality on the daily mean levels for the above measures of particulates, after accounting for seasonal and subseasonal fluctuations in the mortality time series, non-Poisson dispersion, weather variables, and gaseous pollutants. We found positive and statistically significant associations between the daily measures of ambient particle mass and sulfate mass and the deaths from respiratory diseases and diabetes. The mean percentage change in daily mortality (MPC), evaluated at the interquartile range for pollutants averaged over the day of death and the preceding 2 days, for deaths from respiratory diseases was MPC(COH)=6.90% (95% CI: 3.69-10.21%), MPC(Predicted PM2.5)= 9.03% (95% CI: 5.83- 12.33%), and MPC(Sutton sulfate)=4.64% (95% CI: 2.46-6.86%). For diabetes, the corresponding estimates were MPC(COH)=7.50% (95% CI: 1.96-13.34%), MPC(Predicted PM2.5)=7.59% (95% CI: 2.36-13.09%), and MPC(Sutton sulfate)=4.48% (95% CI: 1.08-7.99%). Among individuals older than 65 years at time of death, we found consistent associations across our metrics of particles for neoplasms and coronary artery diseases. Associations with sulfate mass were also found among elderly persons who died of cardiovascular diseases and of lung cancer. These associations were consistent with linear relationships. The associations found for respiratory diseases and for cardiovascular diseases, especially in the elderly, are in line with some of the current hypotheses regarding mechanisms by which ambient particles may increase daily mortality. The positive associations found for cancer and for diabetes may be understood through a general hypothesis proposed by Frank and Tankersley, who suggested that persons in failing health may be at higher risk for external insults through the failure of regulating physiological set points. The association with diabetes may be interpreted in light of recent toxicological findings that inhalation of urban particles in animals increases blood pressure and plasmatic levels of endothelins that enhance vasoconstriction and alter electrophysiology. Further research to confirm these findings and to determine whether they are causal is warranted.

Aged↗
PubMed2002

The health and visibility cost of air pollution: a comparison of estimation methods.

Air pollution from motor vehicles, electricity-generating plants, industry, and other sources can harm human health, injure crops and forests, damage building materials, and impair visibility. Economists sometimes analyze the social cost of these impacts, in order to illuminate tradeoffs, compare alternatives, and promote efficient use of scarce resource. In this paper, we compare estimates of the health and visibility costs of air pollution derived from a meta-hedonic price analysis, with an estimate of health costs derived from a damage-function analysis and an estimate of the visibility cost derived from contingent valuation. We find that the meta-hedonic price analysis produces an estimate of the health cost that lies at the low end of the range of damage-function estimates. This is consistent with hypotheses that on the one hand, hedonic price analysis does not capture all of the health costs of air pollution (because individuals may not be fully informed about all of the health effects), and that on the other hand, the value of mortality used in the high-end damage function estimates is too high. The analysis of the visibility cost of air pollution derived from a meta-hedonic price analysis produces an estimate that is essentially identical to an independent estimate based on contingent valuation. This close agreement lends some credence to the estimates. We then apply the meta hedonic-price model to estimate the visibility cost per kilogram of motor vehicle emissions.

Air Pollutants↗
PubMed1997

Cytokine production by human airway epithelial cells after exposure to an air pollution particle is metal-dependent.

Despite the many epidemiological studies supporting the contention that ambient air pollution particles can adversely affect human health, there is no clear agreement as to a biologically plausible mechanism which can explain the acute mortality and morbidity associated with exposure to particles less than 10 microm in size. We tested the hypothesis that metals present in an air pollution particle can induce the synthesis and expression of the inflammatory cytokines IL-8, IL-6, and TNFalpha. A residual oil fly ash (ROFA) containing the transition metals vanadium, nickel, and iron was used as a model emission source air pollution particle. Normal human bronchial epithelial (NHBE) cells were exposed for either 2 or 24 hr to 0, 5, 50, or 200 microg/ml ROFA. Concentrations of IL-8, IL-6, and TNF-alpha proteins were measured with commercially available ELISA kits. mRNA for these same cytokines was quantified by RT-PCR. NHBE cells exposed to ROFA produced significant amounts of IL-8, IL-6, and TNF, as well as mRNAs coding for these cytokines. Cytokine production was inhibited by the inclusion of either the metal chelator deferoxamine (1.0 mM) or the free radical scavenger dimethylthiourea (1.0 mM). In addition, vanadium containing compounds, but not iron or nickel sulfates, mimicked the effects of intact ROFA. These results demonstrate that metals present in ROFA may be responsible for production and release of inflammatory mediators by the respiratory tract epithelium and suggest that these mediators may contribute to the toxic effects of particulate air pollutants reported in epidemiology studies.

Air Pollutants, Occupational↗
PubMed1992

Microbial bioconversion of pollutants.

Microorganisms totally detoxicate xenobiotics of various chemical structures, which are serious and, in some cases, very hazardous pollutants. At present, the efforts of a number of researchers promoted the establishment in this country of a collection of microorganisms able to degrade volatile toxic pollutants--toluene, isomeric xylenes, styrene, alpha-methylstyrene, crotonaldehyde; widely distributed xenobiotics chlorobenzoic acids; isomeric aryldicarboxylic acids; and ecologically hazardous pollutants such as aromatic nitrocompounds. The active strains-destructors are mainly representatives of the genera Pseudomonas and Rhodococcus. Research into their physiological characteristics, key enzymes, pathways of xenobiotics degradation, genetic mechanisms determining the degradation of these foreign compounds, and behaviour of the strains in a real environment made it possible to develop the theoretical principles of using these microbial cultures to purify real industrial wastes and remediate polluted areas of soil and water. Improvement of the methods of immobilizing the active xenobiotics-degrading strains on cheap and efficient carriers made it possible to significantly intensify the cleanup process of industrial wastes and eliminate a number of problems during the development of the biotechnologies for industrial waste cleanup. Successfully operated at present are the biotechnologies of the local cleanup of waste waters of terephthalate production, microbial purification of industrial waste waters in nylon-66 production from hexamethylenediamine, purification of coke production wastes from phenols, waste waters of polyisocyanate production from aromatic amines, local purification of waste waters in synthetic rubber production from alpha-methylstyrene, acetaldehyde production wastes from crotonaldehyde and mercury. Microbial strains constructed by gene engineering methods for the cleanup of contaminated soils from dicofol and 3-chlorobenzoate were successfully applied (Golovleva et al. 1988).

Biodegradation, Environmental↗
PubMedDate not supplied

Health effects from indoor air pollution: case studies.

In recent years there has been a growing awareness of the health effects associated with the presence of contaminants in indoor air. Numerous agents can accumulate in public buildings, homes and automobiles as a result of ongoing activities that normally occur in these closed spaces. Ventilation is a major factor in the control of indoor air pollutants since proper movement of air can prevent or minimize the build up of compounds in buildings. The recent emphasis on energy conservation has lead to measures which economize on energy for heating and air conditioning, but which also trap pollutants within a building. Three cases of indoor air pollution were investigated. A typical investigation of indoor air pollutant problems includes the following: interviews with building occupants; history of the building with regard to maintenance, pesticide treatment, etc.; a survey of the building and ventilation; and when warranted, sampling and analysis of air. Each case presented is unique in that atypical situations caused agents to accumulate in a building or section of a building. The indoor air problems in these cases were solved by identifying and removing the source of the offending agent and/or improving the ventilation in the building.

Adhesives↗
PubMed1979

Consideration on the effects of pollution at community and population level.

The effects of pollution at population level are considered in relation to demographic characteristics and overall to the birthrate. The direct and indirect effects of pollution on community structure is discussed. The influence of pollution may vary according to the food-chain structure; (as a consequence, the hazard 'ceteris paribus' will be greater in freshwater communities than in marine ones). Relations between 'diversity' and 'stability' are discussed. In addition, the advantages and difficulties in using 'diversity' and 'biotic' indices for monitoring polluted water are taken into account.

Animals↗
PubMedDate not supplied

[Burdens due to noise and air pollution in residents of areas near streets with heavy traffic].

The residents of different streets with varying traffic density and building density were questioned about annoyance due to traffic noise and air pollution. Frequency and extent of annoyance felt, effects of immissions on such living aspects as recreation, or communication, and also the reactions to the disturbance felt (such as closing windows and taking sleeping pills) were investigated. Noise levels as well as particulate matter and gaseous air pollutant concentrations were measured along the streets under investigation. The evaluation of 1300 questionaires showed that reactions to noise were different in different quarters although noise levels were the same. In general, about 40% of residents were heavily disturbed during daytime when the noise level Leq was around 65 dB(A); while for the same noise level at night about 55% reported to be heavily disturbed. Strong correlations were also obtained between annoyance due to noise and that due to air pollution. The results show that annoyance felt is dependent not only on the measured noise levels and/or air pollution concentrations, but that there do exist interactions between the residential quarters and annoyance. These interactions should be considered while fixing the limits and standards.

Air Pollution↗
PubMed1986

[Atmospheric pollution and chronic respiratory diseases].

A national cooperative study was conducted from 1974 to 1976 in twenty-four areas located in six French cities, in order to investigate the relationships of air pollution to ventilatory function and the prevalence of respiratory symptoms. The concentrations of the following pollutants were daily measured: SO2, suspended particulates, NOx. The population included men and women, non manual workers, aged 25 to 59, and children, aged 6 to 10. The respiratory symptoms and other characteristics of the subjects were recorded and their ventilatory function was measured with a dry expirograph. The main results were as following: a) in adults of both sexes, the pollution in SO2 was associated with the prevalence of lower respiratory symptoms. b) in children, it was associated with the prevalence of upper respiratory symptoms. c) in both adults and children, the higher the SO2 concentration, the lower the FEV1. d) no other pollutant was related to respiratory diseases.

Adult↗