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Public views on the links between air pollution and health in Northeast England.

We investigated how public perceptions of the links between air pollution and health varied with contextual factors describing individuals and their locality. Information was collected via postal surveys on 2744 adults resident in five neighborhoods in Northeast England. Perceptions were compared by individual factors (health status, age, and gender) and locality factors (relative deprivation, proximity to industry and district-Teesside or Sunderland, with different amounts of heavy industry). There was relatively little variation in views about air pollution and health links between neighborhoods. The greatest contrasts were found when comparing those living near or further from industry and between the two districts. Any differences were related more to awareness of illness in the neighborhood thought to be affected by air pollution, rather than belief that a particular disease was linked to air pollution. Chronic illness status and age were sometimes found to be associated with perceptions of disease affected by air pollution, but gender and material deprivation were not central to differences in risk perceptions among the population studied. In understanding public perceptions about the links between air quality and health, research should focus on the characteristics of places as well as of people.

Adult↗

Association between air pollution and ischemic cardiovascular emergency room visits.

This study observed the relationship between air pollutants and ischemic cardiac diseases such as angina and acute myocardial infarction in a representative cardiovascular center emergency room in São Paulo, Brazil. Daily emergency room admissions to the Institute of the Heart of the University of São Paulo, as well as data concerning daily air pollutant levels and meteorological variables, were collected from January 1994 to August 1995. Generalized additive Poisson regressions were fitted to the logarithm of the expected values of total emergency room visits due to angina or acute myocardial infarction, controlling for smooth functions of season and weather and indicators for days of the week. All investigated pollutants were positively associated with ischemic cardiovascular disease emergency room visits, and the time lags were relatively short, but only CO presented an effect that was statistically significant. An interquartile range increase in CO was associated with an increase of 6.4% (95% CI: 0.7-12.1) in daily angina or acute myocardial infarction emergency room visits. This result did not change when estimates were done using linear models and natural cubic splines. This study showed that air pollution has a role in cardiovascular morbidity in São Paulo, reinforcing the necessity for air pollutant emission-controlling polices in urban areas.

Aged↗

Air pollution and daily mortality: associations with particulates and acid aerosols.

The association between total daily mortality and air pollution was investigated for a 1-year period (September 1985 through August 1986) in St. Louis and in the counties in eastern Tennessee surrounding Kingston/Harriman. The purpose of this study was to evaluate the relative importance of various measures of particulate and gaseous air pollution as predictors of daily mortality. Concentrations of inhalable particles (PM10), fine particles (PM2.5), the elemental composition of these particles, and aerosols acidity were measured daily during the period of study. The effect of each air pollutant on daily mortality was estimated after controlling for meteorologic and seasonal influences. Total mortality in St. Louis was found to increase 16% (95% CI-1 to 33%) for each 100 micrograms/m3 increase in PM10, and by 17% (95% CI-12 to 57%) in eastern Tennessee. Positive but progressively weaker associations were found with PM2.5, sulfate, and aerosol acidity concentrations in both communities. Associations with gaseous pollutants--sulfur dioxide, nitrogen dioxide, and ozone--were all far from statistical significance. Because of the short monitoring period for daily particulate air pollution, the power of this study to detect associations was limited. Nevertheless, statistically significant associations with PM10 were found in St. Louis, and, more importantly, the estimated effects were consistent between the two communities studied and with other reported analyses of the effects of particles on daily mortality. These data suggest that the acidity of particles is not as important in associations with daily mortality as the mass concentrations of particles.

Aerosols↗

Elementary school absences and PM10 pollution in Utah Valley.

This study assessed the association between school absenteeism and respirable particulate pollution (PM10) in Utah Valley for the six school years of 1985 to 1990. Weekly absenteeism data from the Provo School District and daily data from a single elementary school in the Alpine School District were analyzed for kindergarten through sixth grade. PM10 concentrations during the study period averaged approximately 50 micrograms/m3 with the 24-hr maximum equal to 365 micrograms/m3. Absenteeism was regressed on PM10 pollution levels, temperature, snowfall, and variables indicating day of week, month of school year, and days preceding and following holidays and extended weekends. Estimated associations between absenteeism and PM10 pollution in both data sets were positive, statistically significant (P less than 0.01), and robust to different model specifications. PM10 effects persisted for up to 3 or 4 weeks. Regression results from both data sets indicated that an increase in 28-day moving average PM10 equal to 100 micrograms/m3 was associated with an increase in the absence rate equal to approximately two percentage points, or an increase in overall absences equal to approximately 40%. Similar relationships were observed for all grade levels, although the response of absences to air pollution was generally greater for grades 1-3 compared with grades 4-6. Associations between absenteeism and PM10 pollution were observed even for levels below 150 micrograms/m3.

Age Factors↗

Psychological reactions to air pollution.

Interviews with a large representative sample of Los Angeles residents reveal that these citizens are somewhat aware and concerned about air pollution, but not knowledgeable about its causes. Direct behaviors to reduce causes of pollution or one's exposure to it are rare. A moderate percentage of people seek out information about air pollution or complain about it. Fewer follow state health advisories by reducing automobile driving or restricting activity during air pollution episodes. Preliminary modeling of citizen compliance with air pollution health advisories suggest that personal beliefs about negative health effects are a important predictor of compliance. Finally, modest but significant relationships are noted between ambient photochemical oxidants and anxiety symptoms. The latter finding controls for age, socioeconomic status, and temperature.

Adaptation, Psychological↗

Do migratory or demographic disruptions rule the population impact of pollution in spatial networks?

Ecotoxicology supplies environmental quality criteria mainly based on the potential effects of contaminants on demographic rates of natural populations. Possible impacts through pollutant-induced disruptions of spatial behaviors are totally neglected. Should it be significant to take into account this "second way"? We developed the example of a hypothetical brown trout population living in a river network. We analyzed how behaviors of toxic avoidance or attraction during the spawning migration alter the impact of pollution. Attraction behaviors basically enhanced the bad effect of pollution. More interesting, avoidance behaviors can weakly lift the asymptotic population growth rate, while if there is density-dependent effects on recruitment, pollutant avoidance can actually lead to a substantial drop in equilibrium size. Our model allowed comparing the relative significance of migratory and demographic disruptions for explaining the population impacts of pollution; we thus stress on the need of increasing efforts to develop knowledge relative to toxicant-induced spatial behaviors and to integrate such effects in the definition of environmental quality criteria.

Animal Migration↗

Occurrence and densities of fungi from northern Greek coastal bathing waters and their relation with faecal pollution indicators.

The objective of this study was to determine the frequency and densities of yeasts and filamentous fungi in coastal water samples as well as their correlation with the indicator bacteria of faecal pollution. The prevalence of fungi was investigated in parallel with the standard pollution indicator microorganisms in 197 marine water samples from six northern Greek prefectures during the bathing season May-October 1999. Filamentous fungi were isolated from all the examined samples and yeasts from 29 (14.7%) of them; among the positive samples, their mean counts were 90.9 and 38.4cfu/100 ml, respectively. A total of 23 genera of filamentous fungi and four genera of yeasts were identified. Prevailing genera of filamentous fungi were Penicillium, Aspergillus and Alternaria spp., whereas Candida spp. was the most frequently isolated yeast. Counts of yeasts were significantly (p < 0.01) correlated with those of total and faecal coliforms, whereas no correlation was found between filamentous fungi and the indicator bacteria of faecal pollution. Significantly higher counts of total and faecal coliforms (p < 0.05), and enterococci (p < 0.001), were found during the months with the higher water temperatures and bather numbers. In the six prefectures, significant differences were observed in the counts of filamentous fungi and yeasts as well as in the counts of all the faecal pollution indicators. The results of this study indicate that coastal water can be a path for contamination of swimmers with yeasts and filamentous fungi and that the pollution indicator microorganisms cannot always predict their presence.

Feces↗

Use of a lux-marked rhizobacterium as a biosensor to assess changes in rhizosphere C flow due to pollutant stress.

The flow of carbon from plant roots into soil supports a range of microbial processes and is therefore critical to ecosystem function and health. Pollution-induced stress, which influences rhizosphere C flow is of considerable potential importance, and therefore needs to be evaluated. This paper reports on a method, based on reporter gene technology, for quantifying pollutant effects on rhizosphere C flow. The method uses the lux-marked rhizobacterium Pseudomonas fluorescens, where bioluminescence output of this biosensor is directly correlated with the metabolic activity and reports on C flow in root exudate. Plantago lanceolata was treated with paraquat (representing a model pollutant stress) in a simple microcosm system. The lux-biosensor response correlated closely with C concentrations in the exudate and demonstrated that the pollutant stress increased the C flow from the plantago roots, 24 h after application of the herbicide. The lux-reporter system therefore potentially offers a technique for use in assessing the impact of pollutant stress on rhizosphere C flow through the soil microbial biomass.

Carbon↗

Contribution of stack gases and solid process wastes to the organic pollutant output of thermal waste treatment plants.

Within the scope of fundamental investigations as well as individual research projects (W. Knorr, B. Hentschel, C. Marb. S. Schädel, M. Swerev, O. Vierle, J.-P. Lay, 1999. Rückstände aus der Müllverbrennung-Chancen für eine stoffliche Verwertung von Aschen und Schlacken. Initiativen zum Umweltschutz, 13 ed., Deutsche Bundesstiftung Ulmwelt, Erich Schmidt, Berlin), the Bavarian State Office for Environmental Protection performs emission measurements at thermal waste treatment plants to optimize operation, to accompany and support development of new technologies, and to study the effect of this kind of waste treatment technology on the environment. Based on recent studies (October 1995-July 1999) at six municipal solid waste incinerators (MSWI) in Bavaria all emission streams (solid and gas) are characterized with respect to organic pollutant contents and compared to the emissions of waste pyrolysis. The significant ranges of pollutant concentration as well as the specific congener patterns observed are similar for all MSWI, regardless of differences in technical design and waste input, but differ markedly from those of the pyrolysis products. The overall approach, including the sampling of all output streams and the determination of mass streams and volume flow rates, allows the calculation of the total output of different organic pollutants for waste incineration plants aand to estimate the relative contribution of each of the emission streams to the total pollutant load. Removal efficiencies are also calculated for the air pollution control (APC) systems of the different MSWI plants.

Air Movements↗

A preliminary investigation of persistent organic pollutants in ambient air in Hong Kong.

Air samples were collected for characterisation of PCDD/Fs and other persistent organic pollutants (POPs) such as aldrin, alpha-HCH, beta-HCH, delta-HCH, gamma-HCH, o,p'-DDT, p,p'-DDT, o,p'-DDE, p,p'-DDE, o,p'-DDD, p,p'-DDD, dieldrin, endrin, endosulfan I and II, heptachlor, heptachlor epoxide and hexachlorobenzene during the winter of 2000/2001 at the weather station of the Hong Kong Observatory at Tai Mo Shan (TMS), which is the highest point (approximately 957 m) in Hong Kong, besides the routine monitoring of PCDD/Fs and 200 other toxic air pollutants (TAPs) at two urban TAPs stations at Tsuen Wan and Central & Western. Concentrations of the pollutants detected at TMS station were evaluated and compared to those recorded at the urban stations. Though pesticides including alpha-HCH, hexachlorobenzene, DDT, DDE, heptachlor, and endosulfan I were detected, these pesticides were found at relatively low concentrations of about 0.02-0.23 ng/m3 and should not have any significant health effects. Concentrations of some of the monitored POPs were found to be higher whilst most of the monitored TAPs were at comparable levels to those measured at the urban stations during the same period. According to the Stockholm Convention on POPs (May 2001), the 12 chemicals labelled by the United Nations as the most dangerous are: aldrin, chlordane, DDT, dieldrin, endrin, heptachlor, mirex, toxaphene, hexachlorobenzene, PCBs and dibenzo-p-dioxins/dibenzofurans (PCDDs)/(PCDFs). Given that there has not been any large scale use of organo-chlorine pesticides recorded since the decline of local farming activities in recent years, the results of the present study again show that pesticides and POPs such as PCDDs/PCDFs are ubiquitous environmental contaminants present in the atmosphere of Hong Kong. The findings also indicate that organo-chlorine pesticides and PCDDs/PCDFs are among the most prevalent chlorinated semi-volatile pollutants present in Hong Kong. Results obtained in the present study suggest that selected pesticides may be used as tracers for transport of pollutants for regional air quality study.

Air Pollutants↗

Fungal microflora biodiversity as a function of pollution in Oued Sebou (Morocco).

An inventory of the fungal microflora present in sediments collected at 11 sites along Oued Sebou has been established. The influence of some climatic parameters (temperature, rainfall) and of pollution on the composition of the fungal communities has been questioned. Emericella nidulans, Eurotium amstelodami, Neosartotya fisheri var. glabrum (Ascomycetes), Dreschslera biseptata (Dematiaceae), Penicillium citrinum (Mucedinaceae) and Phoma sp. (Sphaeropsidale) can be considered as strains sensitive to pollution. Penicillium janthelinum, Trichoderma koningii (Mucedinaceae) and Candida albicans (Yeast) were found only at the most polluted sites; Talaromyces flavus (Ascomycete) Rhodotorula rubra, Saccharomyces cerevisiae (Yeasts) and Fusarium oxysporum (Tuberculariales) were more often found at heavily polluted sites than at lightly polluted ones.

Climate↗

Heavy metals in the waters of the Nant-y-Fendrod: change in pollution levels and dynamics associated with the redevelopment of the Lower Swansea Valley, South Wales, UK.

Approximately 240 years (c. 1720-1960) as a world centre for the metal smelting industry left the Lower Swansea Valley as a derelict urban landscape with severe Cu, Zn, Pb, Cd and Ni and metal contamination. Using analysis of archival water quality and discharge records, this paper assesses changes in river pollution over the period 1966-1999 for the Nant-y-Fendrod stream. The marked reduction in metal pollution levels over the period can be linked to the cessation of remaining metal smelting activity and to the rehabilitation and redevelopment measures and their timing. Pollution, both in the past and currently, is shown to be episodic rather than continuous and relationships of high pollution levels to antecedent weather, season, discharge and hydrograph position are explored. Some of the highest levels were recorded during redevelopment itself. Prospects for metal pollution episodes in the Nant-y-Fendrod with further redevelopment in the Lower Swansea Valley in the future are briefly discussed.

Conservation of Natural Resources↗

An economic approach to reducing water pollution: point and diffuse sources.

A review of economic policy towards pollution control is presented which shows that appropriate measures will depend on whether the pollution is of a point or a diffuse nature. Regulation of the former is comparatively straightforward, with command and control and market instruments the tools of pollution control. The advantages and disadvantages of each measure are outlined. However, the inability to monitor emissions at source, precludes the application of point source measures in the case of diffuse source pollution. Instead, methods are required which overcome the need for direct monitoring. Several suggestions that propose ways of achieving this have been put forward and these are described. It is concluded that appropriate measures depend on the particular features of the problem and it is not possible to offer a blanket solution to either point sources or diffuse pollution.

Agriculture↗

Factors influencing mass concentration and chemical composition of fine aerosols during a PM high pollution episode.

Results obtained during a winter field campaign for the fine fractions of particulate matter are presented. A high pollution episode together with an analysis of the main factors, which influence accumulation of pollutants is described. The measurement campaigns were carried out simultaneously at two sites in Northern Italy, Milan and Erba, during the winter of 2000. The daily variability in the mass concentration values and PM2.5/PM10 ratios appeared to be strongly dependent upon meteorological and atmospheric stability conditions and, in particular, wind regimes. During the intensive field campaign a high-pollution episode occurred that led to TSP and fine fraction concentrations well above the attention and alarm thresholds, reaching values of up to 200-250 microg m(-3). The elemental concentrations were determined by ED-XRF analysis. The elemental composition of the particulate matter indicated that crustal matter oxides (soil dust) were the main component in particles with aerodynamic diameter d(ae) > 10 microm. They were an important part also in particles with 2.5 < d(ae) < 10 microm, but strongly decreased in particles with d(ae) < 2.5 microm. In the finer fraction sulphates nitrogen and carbon compounds played a major role. The temporal patterns of mass and elemental concentrations, as well as the main components of PM were very similar at the two sites. The high-pollution episode was recorded at many locations in the Po plain, highlighting the role of meteorology and thermodynamic atmospheric conditions on pollution build-up on a large area.

Aerosols↗

Critical levels of atmospheric pollution: criteria and concepts for operational modelling of mercury in forest and lake ecosystems.

Mercury (Hg) is regarded as a major environmental concern in many regions, traditionally because of high concentrations in freshwater fish, and now also because of potential toxic effects on soil microflora. The predominant source of Hg in most watersheds is atmospheric deposition, which has increased 2- to >20-fold over the past centuries. A promising approach for supporting current European efforts to limit transboundary air pollution is the development of emission-exposure-effect relationships, with the aim of determining the critical level of atmospheric pollution (CLAP, cf. critical load) causing harm or concern in sensitive elements of the environment. This requires a quantification of slow ecosystem dynamics from short-term collections of data. Aiming at an operational tool for assessing the past and future metal contamination of terrestrial and aquatic ecosystems, we present a simple and flexible modelling concept, including ways of minimizing requirements for computation and data collection, focusing on the exposure of biota in forest soils and lakes to Hg. Issues related to the complexity of Hg biogeochemistry are addressed by (1) a model design that allows independent validation of each model unit with readily available data, (2) a process- and scale-independent model formulation based on concentration ratios and transfer factors without requiring loads and mass balance, and (3) an equilibration concept that accounts for relevant dynamics in ecosystems without long-term data collection or advanced calculations. Based on data accumulated in Sweden over the past decades, we present a model to determine the CLAP-Hg from standardized values of region- or site-specific synoptic concentrations in four key matrices of boreal watersheds: precipitation (atmospheric source), large lacustrine fish (aquatic receptor and vector), organic soil layers (terrestrial receptor proxy and temporary reservoir), as well as new and old lake sediments (archives of response dynamics). Key dynamics in watersheds are accounted for by quantifying current states of equilibration in both soils and lakes based on comparison of contamination factors in sediment cores. Future steady-state concentrations in soils and fish in single watersheds or entire regions are then determined by corresponding projection of survey data. A regional-scale application to southern Sweden suggests that the response of environmental Hg levels to changes in atmospheric Hg pollution is delayed by centuries and initially not proportional among receptors (atmosphere >> soils not equal sediments>fish; clearwater lakes >> humic lakes). This has implications for the interpretation of common survey data as well as for the implementation of pollution control strategies. Near Hg emission sources, the pollution of organic soils and clearwater lakes deserves attention. Critical receptors, however, even in remote areas, are humic waters, in which biotic Hg levels are naturally high, most likely to increase further, and at high long-term risk of exceeding the current levels of concern: </=0.5 mg (kg fw)(-1) in freshwater fish, and 0.5 mg (kg dw)(-1) in soil organic matter. If environmental Hg concentrations are to be reduced and kept below these critical limits, virtually no man-made atmospheric Hg emissions can be permitted.

Air Pollutants↗

Applications of redundancy analysis for the detection of chemical response patterns to air pollution in lichen.

The lichens Ramalina celastri (Spreng.) Krog & Swinsc., Punctelia microsticta (Müll. Arg.) Krog and Canomaculina pilosa (Stizenb.) Elix & Hale were transplanted simultaneously to 17 urban-industrial sites in a northwestern area of Córdoba city, Argentina. The transplantation sites were set according to different environmental conditions: traffic, industries, tree cover, building height, topographic level, position in the block and distances from the river and from the power plant. Three months later, chlorophyll a, chlorophyll b, phaeophytin a, soluble proteins, hydroperoxy conjugated dienes, malondialdehyde concentration and sulfur accumulation were determined, and a pollution index was calculated for each sampling site. Redundancy analysis was applied to detect the variation pattern of the lichen variables that can be 'best' explained by the environmental variables considered. The present study provides information about both the specific pattern response of each species to atmospheric pollution, and environmental conditions that determine it. As regards pollutants emission sources R. celastri showed a chemical response associated mainly with pollutant released by the power plant and traffic. P. microsticta and C. pilosa responded mainly to industrial sources. Regarding environmental conditions that affect the spreading of air pollutants and their incidence on the bioindicator, the topographic level and tree cover surrounding the sampling site were found to be important for R. celastri, tree cover surrounding the sampling site and the building height affected P. microsticta, while building height did so for C. pilosa.

Air Pollutants↗

Toxicity of the 13 priority pollutant metals to Vibrio fisheri in the Microtox chronic toxicity test.

The Microtox Acute Toxicity Test has been successfully used to measure the toxicity of metals and other pollutants at high concentrations (ppm) in selected environmental samples. However, metals and other toxicants are often found in much lower concentrations (ppb) in many municipal wastewaters and receiving waters. In order to assess the toxicity of these pollutants in these samples, a more sensitive toxicity assay is needed. The Microtox chronic toxicity test has been developed to measure the sublethal effect of toxicants over multiple generations of the test species, Vibrio fisheri. In this study, the toxicity of the 13 priority pollutant metals [i.e. As, Se, Cd, Cr (III and VI), Cu, Pb, Sb, Ag, Tl, Zn, Be, Hg and Ni] to V. fisheri was evaluated using the Microtox chronic toxicity test. In this test, the inhibitory concentration (IC), lowest observable effect concentration (LOEC), and no observable effect concentration (NOEC) were obtained after 22-h of incubation at 27+/-1 degrees C, by comparing the light output of the control to that of the test sample. Among the 13 priority pollutant metals, beryllium (Be) was found to be the most toxic in the test (LOEC=0.742-1.49 microg/l) while thallium (Tl) was the least toxic (LOEC=3840-15300 microg/l). The LOECs for copper (as Cu) and lead (Pb) in reagent (ASTM Type I) water were 6.78-13.6 microg/l and 626-1251 microg/l, respectively. The toxicity of copper sulfate (as Cu) in reagent water was shown and significantly reduced with the addition of natural organic matter (fulvic acid) or EDTA to the sample. The LOEC values for the 13 priority pollutant metals in this test were comparable to or lower than those reported for commonly used aquatic toxicity tests, such as the Ceriodaphnia dubia assay.

Benzopyrans↗

The longevity of minewater pollution: a basis for decision-making.

Pollution from abandoned mines is a serious, widespread and increasingly common cause of surface water degradation in the LOIS study region. Indeed, in some areas of the UK it is now the single greatest cause of freshwater pollution. Remediation of such pollution in the long-term is probably best achieved by passive treatment, which has the advantage of concentrating expenditure in capital costs, with only modest financial commitments for long-term maintenance. To plan such remediation, however, it is important to have an understanding of the physical and chemical processes governing pollutant release over scales of many decades. By analysing water quality records for major abandoned mine discharges in Scotland, Wales and Cornwall, long-term acidity generation is shown to have two components: "vestigial' and "juvenile'. The vestigial component relates to the geochemical trauma which occurs as abandoned mine voids are allowed to fill with water for the first time, taking ferrous and ferric hydroxysulphate salts (intermediate products of pyrite oxidation) into solution. Dissipation of vestigial acidity is primarily controlled by the hydraulic retention time of the flooded mine system, and will generally be accomplished in less than 40 years. Juvenile acidity arises from on-going pyrite oxidation in the zone of water table fluctuation within the mined system, and can be expected to continue for many hundreds of years, until the supply of pyrite is finally exhausted. Rational planning for the remediation of minewater pollution should be based on intensive treatment of discharges while the vestigial acidity is being depleted, followed by long-term passive treatment of the juvenile acidity.

Coal↗