Analysis of atmospheric conditions during air pollution episodes in Ankara, Turkey

This paper presents a detailed analysis of the meteorological conditions that are associated with strong air pollution episodes in Ankara, Turkey. Based on climatological and air quality data [SO2 and TSP (total suspended particulates)] obtained for the winter months during 1989-1994, the analysis showed that the presence of weak atmospheric pressure gradients and warm air advection were the most important factors leading to high SO2 and TSP concentrations. In addition, the onset of the high air pollution episodes was generally associated with a trend toward negative vorticity at the 850-hPa level.     

空气和土壤中酞酸酯的污染及其相关性分析

对天津市11个采样点的空气颗粒物和土壤样品进行采样调查,采用气相色谱/质谱联用仪分析样品中15种酞酸酯类化合物(PAEs)的含量。结果表明,11个采样点空气颗粒物样品中总酞酸酯类化合物(TPAEs)以体积计质量浓度为90.87～1355.70ng/m3,以质量计质量浓度为783.84～8712.37mg/kg;土壤中TPAEs质量浓度为0.53～2.53mg/kg。邻苯二甲酸二丁酯(DBP)与邻苯二甲酸二(2-乙基己基)酯(DEHP)是空气颗粒物和土壤样品中的主要污染物。土壤与空气颗粒物中TPAEs和DBP存在相关关系,Pearson相关系数分别为0.825和0.864(双尾检验,显著性水平0.01),且空气颗粒物中各种PAEs浓度为土壤PAEs浓度的数百至数万倍,说明空气沉降可能是土壤PAEs污染的主要原因之一。     

Lead exposure of small herbivorous vertebrates from atmospheric pollution

Concentrations of Pb in livers of willow grouse (Lagopus lagopus), black grouse (Tetrao tetrix), and hare (Lepus timidus) were determined in samples collected during the period 1990-92 from 77 locations distributed across Norway. Our objective was to elucidate the impact of long-range atmospheric transport on the Pb exposure of the animals. The moss Hylocomium splendens was measured for atmospheric Pb deposition and Pb in soil at 60-cm depth was determined to reflect the natural geochemical background at the study locations. Strong positive relationships were found between Pb in liver and atmospheric deposition of Pb for all species and age groups studied. Results indicate that long-range atmospheric transport was the main source of Pb in the animals studied. This conclusion was supported by Pb analysis of typical food plants for the animals. Correlation between Pb in liver and Pb in soil mineral matter was observed only when considering sites with very low impact of atmospheric deposition. Even though the observed liver Pb concentrations may seem low (< or =12 microg g(-1) dw) they approach levels where sub-lethal effects cannot be ignored.     

Inhalable urban atmospheric particulate matter in a semi-arid climate: The case of Santiago De Chile

The city of Santiago is characterized by low average rainfall and atmospheric thermal inversion layers. Air pollution levels are high. Dichotomous sampling of inhalable particulate matter (IPM) has been conducted at a fixed station on the Universidad de Santiago de Chile (USACH) campus from October 1981 to March 1983. The air sampling inlet cutoff was 15 μm, the fractioning cut being located at a 2.5 μm aerodynamic diameter. The samples were analyzed qualitatively by X-ray fluorescence (XRF) spectrometry. Information on the IPM component of urban air pollution in Santiago by particle sizing sampling methods was not previously available, nor had XRF spectrometry been applied to local IPM samples. A multivariate statistical analysis of the body of data comprising sample masses and XRF elemental intensities is presented and discussed. The group of elements Al, Si, K, Ca, Ti and Fe shows strong statistical correlations in the coarse particle fraction; correlations in the fine particle fraction include Br/Pb. Evidence for seasonal variations in the air pollution pattern is presented. Pollution by sulfur is discussed.     

转炉炼钢大气污染环境评价问题探讨

为了探讨转炉炼钢大气污染环境评价的关键问题,以某大型钢铁集团炼钢厂扩建项目为基础,分析了该类建设项目工艺流程和产污环节;确定了转炉炼钢的重点污染因子是粉尘、烟尘和SO2等.通过对转炉炼钢烟尘治理措施的有效性分析,得出了该扩建项目大气污染物粉尘、烟尘和SO2等能达标排放并满足总量控制指标,符合清洁生产要求.     

Effect of atmospheric electricity on dry deposition of airborne particles from atmosphere

The electric mechanism of dry deposition is well known in the case of unattached radon daughter clusters that are unipolar charged and of high mobility. The problematic role of the electric forces in deposition of aerosol particles is theoretically examined by comparing the fluxes of particles carried by different deposition mechanisms in a model situation. The electric mechanism of deposition appears essential for particles of diameter 10–200 nm in conditions of low wind speed. The electric flux of fine particles can be dominant on the tips of leaves and needles even in a moderate atmospheric electric field of a few hundred V m⁻¹ measured over the plane ground surface. The electric deposition is enhanced under thunderclouds and high voltage power lines. Strong wind suppresses the relative role of the electric deposition when compared with aerodynamic deposition. When compared with diffusion deposition the electric deposition appears less uniform: the precipitation particulate matter on the tips of leaves and especially on needles of top branches of conifer trees is much more intensive than on the ground surface and electrically shielded surfaces of plants. The knowledge of deposition geometry could improve our understanding of air pollution damage to plants.     

Urban atmospheric pollution: personal exposure versus fixed monitoring station measurements

We initiated the PETER (pedestrian environmental traffic pollutant exposure research) project to investigate pedestrians' exposure to traffic related atmospheric pollutants, based on data obtained with the collaboration of selected categories of pedestrian urban workers. We investigated relations between roadside personal exposure levels of volatile aromatic hydrocarbons (including benzene) and particulate matter <10 microm (PM10) among traffic police (n = 126) and parking wardens (n = 50) working in downtown Bologna, Italy. Data were collected from workshifts throughout four 1-week periods in different seasons of 2000-2001. For benzene and PM10, comparisons were made with measurements by fixed monitoring stations, and influence of localized traffic intensity and meteorological parameters was examined. Roadside personal exposure to benzene correlated more strongly with other volatile aromatic hydrocarbons (toluene, xylenes and ethylbenzene) than with PM10. Benzene and PM10 personal exposure levels were higher than fixed monitoring station values (both p<0.0001). At multivariate analysis, benzene and PM10 data from fixed monitoring stations both correlated with meteorological variables, and were also influenced by localized traffic intensity. Plausibly because of the downtown canyon-like streets, weather conditions (during a period of drought) only marginally affected benzene personal exposure, and moderately affected PM10 personal exposure. These findings reinforce the concept that urban atmospheric pollution data from fixed air monitoring stations cannot automatically be taken as indications of roadside exposures.     

Assessment of atmospheric pollution from toxic heavy metals in two cities in India

Atmospheric concentrations of Pb, Cd, Cu and Zn have been measured at different locations in Bombay. The concentration levels of these metals in blood and teeth of Bombay residents were also measured to assess the current and integrated exposure. Higher atmospheric concentrations were observed in higher vehicular traffic zones in Bombay. Environmental monitoring of Pb, Cd, Cu and Zn was also carried out at Moradabad, the largest production and exporting centre of brass wares in India. Surface soil concentrations of these metals were also measured in Moradabad and Bombay. The analysis of samples was carried out by differential pulse anodic stripping voltammetry (DPASV). The study indicates that automobile exhaust is the dominant source for heavy metals in the environment of Bombay whereas the brass industry is responsible for enhanced concentrations of these metals in Moradabad.     

The linear accumulation of atmospheric mercury by vegetable and grass leaves: Potential biomonitors for atmospheric mercury pollution

One question in the use of plants as biomonitors for atmospheric mercury (Hg) is to confirm the linear relationships of Hg concentrations between air and leaves. To explore the origin of Hg in the vegetable and grass leaves, open top chambers (OTCs) experiment was conducted to study the relationships of Hg concentrations between air and leaves of lettuce (Lactuca sativa L.), radish (Raphanus sativus L.), alfalfa (Medicago sativa L.) and ryegrass (Lolium perenne L.). The influence of Hg in soil on Hg accumulation in leaves was studied simultaneously by soil Hg-enriched experiment. Hg concentrations in grass and vegetable leaves and roots were measured in both experiments. Results from OTCs experiment showed that Hg concentrations in leaves of the four species were significantly positively correlated with those in air during the growth time (p?<?0.05), while results from soil Hg-enriched experiment indicated that soil-borne Hg had significant influence on Hg accumulation in the roots of each plant (p?<?0.05), and some influence on vegetable leaves (p?<?0.05), but no significant influence on Hg accumulation in grass leaves (p?>?0.05). Thus, Hg in grass leaves is mainly originated from the atmosphere, and grass leaves are more suitable as potential biomonitors for atmospheric Hg pollution. The effect detection limits (EDLs) for the leaves of alfalfa and ryegrass were 15.1 and 22.2 ng g^–1, respectively, and the biological detection limit (BDL) for alfalfa and ryegrass was 3.4 ng m^–3.     

Fine particles and oxidant pollution: developing an agenda for cooperative research

This paper describes a background for the North American Research Strategy for Tropospheric Ozone (NARSTO) cooperative program integrating studies of O3 and PM2.5. It discusses several important aspects for rationalizing NARSTO's trinational investigative approach, including (1) an outlook on the state of knowledge about fine particles in the troposphere and their origins in Canada, Mexico, and the United States; (2) the need for enhancement and strengthening of key field measurements in relation to tropospheric chemistry and a health effects component; and (3) the use of a central theme for advancing air quality modeling using evolving techniques to integrate and guide key process-oriented field campaigns. The importance of organizing a scientific program to acquire "policy-relevant" information is stressed, noting cooperative research directions that address combined PM2.5 and O3 issues, illustrated through exploration of hypothetical pathways of PM2.5 response to choices of O3 and PM precursor emission reductions. The information needed for PM2.5 research is noted to intersect in many cases with those of O3, but diverge in other cases. Accounting for these distinctions is important for developing NARSTO's strategy over the next decade.     

Stochastic modeling of atmospheric pollution: a spatial time-series framework. Part I: methodology

A geostatistical framework for joint spatiotemporal modeling of atmospheric pollution is presented. The spatiotemporal distribution of concentration levels is modeled as a joint realization of a collection of spatially correlated time series. Parametric temporal trend models, associated with long-term pollution variability are established from concentration profiles at monitoring stations. Such parameters, e.g., amplitude of seasonal variation, are then regionalized in space for determining trend models at any unmonitored location. The resulting spatiotemporal residual field, associated with short-term pollution variability, is also modeled as a collection of spatially correlated residual time series. Stochastic conditional simulation is proposed for generating alternative realizations of the concentration spatiotemporal distribution, which identify concentration measurements available at monitoring stations. Simulated realizations also reproduce the histogram of the sample data, and a model of their spatiotemporal correlation. Such alternative concentration fields can be used for risk analysis studies.     

Assessment of metal concentrations in atmospheric particles from Burnaby Lake,British Columbia,Canada

Trace metals were assessed in atmospheric particulates at Burnaby Lake, in the greater Vancouver area of British Columbia to assess concentrations, particle size distributions and deposition rates to an urban watershed. Week-long samples were collected over a period of 18 weeks in 1995 using a 13 stage low pressure impactor (LPI). Samples were analysed using inductively coupled plasma atomic emission spectroscopy (ICP). Aluminum, boron, calcium, iron, magnesium, manganese, sodium and strontium had a similar time series pattern and particle size distribution. For these metals, maximum concentrations occurred during weeks of low precipitation and exhibited a large peak in mid June. Their particle size distribution was mostly dominated by a large peak between 1.7–18.4 μm with a secondary peak at <0.08 μm. Metal concentrations were generally one to three orders of magnitude higher than those measured in a rural location 100 km away from Burnaby Lake but similar to those measured in urban Taipei, Taiwan. Concentrations of the highly toxic metals, arsenic, cadmium and lead were within current air quality guidelines, however boron exceeded the Ontario Ministry of Environment ambient air quality standard in two of the 16 samples. Deposition velocities ranged between 0.22 and 13 cm s⁻¹ with the largest values corresponding to the coarse particle mode. Mean deposition rates ranged between 4.0 μg m⁻² d⁻¹ and 650 mg m⁻² d⁻¹. Depending on the metal, yearly loadings to the watershed ranged from 90 kg to several thousand tonnes. Calcium, aluminum, boron and magnesium had the highest metal loadings to the watershed. Manganese also had relatively high loadings, a reflection of the high traffic density in the area. The relatively high metal deposition rates indicate that metal contribution from atmospheric sources may represent a significant portion of the total metal load to the Burnaby Lake watershed.     

Physiological indicators and susceptibility of plants to acidifying atmospheric pollution: a multivariate approach

Plant susceptibility to acidifying atmospheric pollution was investigated for a wide range of plant species under normal environmental conditions. Physiological and biochemical parameters were recorded for each plant species. Multivariate analysis using hierarchical clustering, principal component analysis ordination, as well as regression analysis were used to interpret the data. Analysis of the data separated plants into pioneer tree species, ruderal herbaceous species and climax, slow growing species. Pioneer and ruderal species showed higher potential for foliar nitrate assimilation coupled with higher base cation content and a tendency to a more neutral leaf pH than climax species. Acidic buffering capacities for leaf tissue from pioneer and ruderal species were higher than those of climax species. Nitrate assimilation produces hydroxyl ions, which in conjunction with high base cation content and more neutral leaf pH, provides better metabolic buffering and therefore make pioneer and ruderal species less susceptible to acidifying inputs. Climax species are less able to buffer against acidifying inputs and are subsequently more prone to acidifying air pollution damage.     

The radiative effect of atmospheric pollution: Latitudinally dependent radiation calculations including cloud contribution

In this paper, we have developed a radiation scheme based on the discrete-ordinate method into which a comparatively thick cloud layer can be incorporated for inhomogeneous aerosol atmospheres. Using the above radiation scheme, we performed calculations of the effect of clouds upon the inhomogeneous aerosol atmospheres, including the effects of optical depth, vertical distribution and extent of cloud layer. Calculations were also carried out for the local albedo, total absorption and diffuse transmission at each latitude belt, considering a land-sea distribution and a latitudinal variation of cloudiness, for six realistic model aerosol atmospheres. A 0.50 μm flux of the solar radiation is used for this study. The main conclusions of the radiative calculations may be summarized as follows.

• 1.(1) For the same optical thickness, a densely stratified cloud layer within the lower aerosol troposphere is apt to reflect the solar radiation much less effectively than other stratifications of cloud. If cloud layers are present at higher levels, absorption of solar radiation within the atmosphere would decrease considerably.
• 2.(2) Cloudiness and/or cloud thickness play a very important role upon the global heat balance problems and should never be ignored in studying the effects of increased aerosols upon climate, because contrary to the cloudless condition, heating of the earth-atmosphere system would tend to be induced by an increase of aerosols in the atmosphere where clouds are present. Because of the high surface albedo, an increase of aerosols reduces the reflectivity at the snow-covered high latitude belts, regardless of the effects of cloud.
• 3.(3) By the perturbation of adding aerosols into the troposphere or the stratosphere the diffuse transmission increases at the ground level. However, this effect is offset by the direct exponential attenuation of solar flux, and as a result, the total solar radiation reaching the ground is somewhat reduced.
• 4.(4) The absorption of solar radiation within the atmospheres due to aerosols would reach near 10% of incident solar flux for injection of a fairly massive amount of aerosols into the troposphere or the stratosphere due to great volcanic eruptions or man's impact.

     

Seveso: from pollution to regulation

The first part of the paper analyses the Seveso accident, which occurred in 1976 in northern Italy. It focuses mainly on sociological and organisational aspects, pointing to the lack of preparation and the improvisation in response from the company and the public authorities. Despite such inadequacies and despite all suffering, community recovery was finally accomplished. Yet, to some extent, this local success in recovery was achieved by exporting part of the problem. In this sense Seveso is representative of high technology industry, where successful consumer satisfaction has so far been sustained by the 'externalising' of its environmental costs and also social problems. The second part of the paper analyses and discusses the 'Seveso Directive', whose approval was accelerated by the Seveso accident. This establishes European legislation on major accident hazards, of which an essential feature is publicity about industrial operations.     

Photochemical oxidant pollution and vegetation: effects of mixtures of gases, fog and particles

Photochemical 'smog' contains mixtures of gases (e.g. ozone, nitrogen dioxide), and dry particles (e.g. nitrates). Intermittent fog in the same geographical area can be acidic with high concentrations of nitric acid. Results from recent field studies in the Los Angeles Basin have emphasized the relative toxicity of these components of photochemical air pollution. Studies have focused on gaseous+fog or gaseous+dry particulate effects on conifers, gaseous+fog effects on crops, and the effects of trace pollutants produced during generation of ozone on crops. Data from these studies indicate that direct alterations in growth and physiological responses were observed only with gaseous pollutants (primarily ozone), or repeated applications of highly acidic fogs (pH < 2.7). Direct particle dry deposition effects are unclear. Few interactions have been found between gaseous pollutants and acidic fog. Charcoal-filtered open-top chambers are highly effective in removing pollutants in the following order: fog (100%) > peroxyacetyl nitrate > ozone > nitrogen dioxide > sulfur dioxide > nitrate ion > ammonium ion > sulfate ion. However, nitric oxide concentrations are higher in charcoal-filtered chambers than in ambient air. The studies point out the importance of considering other components of photochemical pollution in addition to ozone, especially when investigating subtle, long-term effects on vegetation.     

Phytoextraction potential of two Rumex acetosa L. accessions collected from metalliferous and non-metalliferous sites: effect of fertilization

Metal tolerance and phytoextraction potential of two common sorrel (Rumex acetosa L.) accessions, collected from a Pb/Zn contaminated site (CS, Lanestosa) and an uncontaminated site (UCS, Larrauri), were studied in fertilized and non-fertilized pots prepared by combining soil samples from both sites in different proportions (i.e., 0%, 33%, 66% and 100% of Lanestosa contaminated soil). The original metalliferous mine soil contained 20480, 4950 and 14 mg kg(-1) of Zn, Pb and Cd, respectively. The microcosm experiment was carried out for two months under greenhouse controlled conditions. It was found that fertilization increased mean plant biomass of both accessions as well as their tolerance. However, only the CS accession survived all treatments even though its biomass decreased proportionally according to the percentage of contaminated mine soil present in the pots. This metallicolous accession would be useful for the revegetation and phytostabilization of mine soils. Due to its high concentration and bioavailability in the contaminated soil, the highest values of metal phytoextracted corresponded to Zn. The CS accession was capable of efficiently phytoextracting metal from the 100% mine soil, indeed reaching very promising phytoextraction rates in the fertilized pots (6.8 mg plant(-1) month(-1)), similar to the ones obtained with hyperaccumulator plants. It was concluded that fertilization is certainly worth being considered for phytoextraction and revegetation with native plants from metalliferous soils.