Indoor air pollution from particulate matter emissions in different households in rural areas of Bangladesh

Indoor air pollution from the combustion of traditional biomass fuels (wood, cow dung, and crop wastes) is a significant public health problem predominantly for poor populations in many developing countries. It is particularly problematic for the women who are normally responsible for food preparation and cooking, and for infants/young children who spend time around their mothers near the cooking area. Airborne particulate matter (PM) samples were collected from cooking and living areas in homes in a rural area of Bangladesh to investigate the impact of fuel use, kitchen configurations, and ventilation on indoor air quality and to apportion the source contributions of the measured trace metals and BC concentrations. Lower PM concentrations were observed when liquefied petroleum gas (LPG) was used for cooking. PM concentrations varied significantly depending on the position of kitchen, fuel use and ventilation rates. From reconstructed mass (RCM) calculations, it was found that the major constituent of the PM was carbonaceous matter. Soil and smoke were identified as components from elemental composition data. It was also found that some kitchen configurations have lower PM concentrations than others even with the use of low-grade biomass fuels. Adoption of these kitchen configurations would be a cost-effective approach in reducing exposures from cooking in these rural areas.     

Aggregate resources inventory in Ontario,Canada

Ontario has an abundance of aggregate resources; however, their location is fixed by nature and they are not always found in the areas of greatest demand. Over 120 million tonnes are produced yearly. Much of this production is in urban fringe areas. Comprehensive planning and resource management strategies, based on an appropriate planning framework and a sound knowledge of the total mineral aggregate resource base, are required to make the best use of available resources. To achieve this, Ontario's Mineral Aggregate Resource Policy requires 1) the Ontario Ministry of Natural Resources to prepare a detailed inventory of the aggregate resources, including location, quality, quantity and extractive activity, and 2) the recognition of aggregate resources in municipal official plans.     

Size distribution of methylmercury associated with particulate and dissolved organic matter in freshwaters

Water samples were collected from 20 wetland, river and lake sites across Eastern Ontario and Western Quebec to investigate the distribution of methylmercury (MeHg) associated with various size fractions of dissolved organic matter (DOM). Tangential Flow UltraFiltration (TUF) was used to fractionate DOM by nominal molecular size (<0.2 μm, <300 kDa, <30 kDa, <5 kDa and <1 kDa). DOM fluorescence (DOM FL) and absorbance (DOC Abs) were used to quantify DOM photoreactivity and aromaticity in each sample. Significant differences in the size-associated distribution of MeHg, Dissolved Organic Carbon (DOC), DOM FL, and DOM Abs were observed between wetlands, rivers, and lakes. The low molecular weight (LMW) fraction (<5 kDa) in wetlands contained the majority of MeHg (70.0 ± 13.8%), DOC (56.1 ± 9.4%), and DOM FL (77.4 ± 7.5%). DOM FL was also high in the LMW fraction for rivers (60.6 ± 25%) and lakes (75.2 ± 16.9%). Mean MeHg concentrations in the LMW fraction of lakes (41 ± 26 pg L^− 1) and rivers (32 ± 19 pg L^− 1) were substantial but much lower than wetlands. Rivers had the highest percentage of methylmercury (38.0 ± 23.5%) in the particulate (>0.2 µm) fraction. This research highlights the importance of low molecular weight dissolved organic matter in methylmercury fate. For example, a large proportion of MeHg was found in the LMW weight fractions (mean = 47.3 ± 25.4%) of the wetlands, rivers, and lakes in this study.     

Some elements comprising particulate matter during summer in waters of various environments in British Columbia, Canada

Multi-elemental traces comprising particulate matter in natural water collected during summer in 1978 and 1979 from British Columbia, Canada, were analyzed by α-particle excited X-ray fluorometry. Common elements from all waters examined were Si, Cl, Ca and Fe. The similarity of their distribution in different aquatic environments was statistically analyzed. They were distributed homogeneously in the marine environment but heterogeneously in the freshwater environments. No heavy metals concerned with the environmental standards were detected for all waters examined.     

Fine-scale mercury trends in temperate deciduous tree leaves from Ontario, Canada

This study focused on the value of deciduous leaves as biomonitors of total mercury (THg). Leaf samples were collected from a range of deciduous species from five sampling sites in the province of Ontario, Canada. These included a site in the northwest (the Experimental Lakes Area, ELA), two sites in central Ontario (the town of Dorset and the Centre for Atmospheric Research Experiments, CARE), and two sites in the southeast (Sandbanks Provincial Park, SBPP and the City of Kingston). The sampled species exhibited distinctive species-specific differences with red oaks consistently having lower leaf THg concentrations than all maple species, while black and white ash leaves had the highest concentrations. Spatially, leaves collected across the distance between ELA and SBPP (~ 1500 km apart) had overlapping THg concentrations between 20 and 40 ng/g. Unexpectedly, leaves from urban parks of Kingston had considerably lower THg concentrations (< 25 ng/g) than the other sites, which suggested leaves may not reflect subtle gradients of atmospheric THg found under field conditions. Leaf THg increased with the growing season, with highest THg leaf concentrations found in early autumn just before senescence. Microspatial differences within a single tree, such as position on a branch are important, since higher mercury concentrations were associated with leaves positioned deeper into the canopy relative to outer leaves more exposed to wind turbulence and sunlight. Within any single leaf, THg concentrations were highest in the leaf tissue, and consistently distributed, while the vein and petiole tissue had lower THg concentrations. There was no relationship between THg concentrations and leaf area. Using deciduous tree leaves as regional temporal monitors of bioavailable mercury may be feasible, but careful selection of leaf sampling sites on the tree itself and the timing is of utmost importance for ensuring consistent and high quality biomonitoring data.     

Characterization of particulate emissions from occupant activities in offices

This paper characterizes the relationship between occupant activities and indoor air particulate levels in a non-smoking office building. Occupant activities were recorded on video. Particulate concentrations were monitored by three optical particle counters (OPCs) in five size ranges at three heights. Particulate mass concentrations were measured gravimetrically and bioaerosol concentrations were determined by impaction methods. Occupant activities and number concentrations were determined with 1-min resolution over a 1-week period. Occupant activities such as walking past or visiting the monitoring site explained 24-55% of the variation of 1- to 25-micron diameter particle number concentrations. Statistical models associating particulate concentrations with occupant activities depended on the size fraction and included an autocorrelative term. Occupant activities are estimated to contribute up to 10 micrograms m-3 in particulate concentrations per person. Number concentrations of particles smaller than 1 micron had little correlation with indoor activities other than cigarette smoking and were highly correlated with outdoor levels. The method can be used to characterize emissions from activities if rapid measurements can be made and if activities can be coded from the video record.     

Spectrofluorometric properties of dissolved organic matter from Central and Southern Ontario streams and the influence of iron and irradiation

Fluorescence measurements were used to compare characteristics of dissolved organic matter (DOM) from distinctly different origins: boreal, agricultural and urban streams as well as a storm runoff pond and the outlet of a tertiary wastewater treatment plant. The primary goal was to determine if differences among stream types could be detected using DOM fluorescence in lieu of isolated fulvic acids (FA). Differences in peak excitation and peak emission wavelengths, fluorescence integrated over the 3-D matrix volume integrated fluorescence (VIF), and in a fluorescence index (FI) were examined. In general, peak fluorescence excitation and emission wavelengths as well as FI best distinguished DOM from the various origins. Results suggested that DOM from the boreal streams was of a higher molecular weight and more complex than that of agricultural and urban streams. The effects of irradiation as well as Fe on fluorescence of natural stream waters were also investigated, both of which decreased the ability of optical properties to distinguish DOM source.     

Sources and properties of non-exhaust particulate matter from road traffic: a review

While emissions control regulation has led to a substantial reduction in exhaust emissions from road traffic, currently non-exhaust emissions from road vehicles are unabated. These include particles from brake wear, tyre wear, road surface abrasion and resuspension in the wake of passing traffic. Quantification of the magnitude of such emissions is problematic both in the laboratory and the field and the latter depends heavily upon a knowledge of the physical and chemical properties of non-exhaust particles. This review looks at each source in turn, reviewing the available information on the source materials and particles derived from them in laboratory studies. In a final section, some of the key publications dealing with measurements in road tunnels and the roadside environment are reviewed. It is concluded that with the exception of brake dust particles which may be identified from their copper (Cu) and antimony (Sb) content, unequivocal identification of particles from other sources is likely to prove extremely difficult, either because of the lack of suitable tracer elements or compounds, or because of the interactions between sources prior to the emission process. Even in the case of brake dust, problems will arise in distinguishing directly emitted particles from those arising from resuspension of deposited brake dust from the road surface, or that derived from entrainment of polluted roadside soils, either directly or as a component of road surface dust.     

Natural, anthropogenic and fossil organic matter in river sediments and suspended particulate matter: a multi-molecular marker approach

Different classes of organic matter (OM) have been systematically investigated in sediments and suspended particulate matter (SPM) along the Danube River in order to understand causes of compositional changes. Analytical pyrolysis revealed the dominance of natural organic matter (NOM) in most of the samples. The predominance of aquatic biomass is evident mainly from the abundance of organonitrogen compounds and phenol distributions. As the river enters a forested gorge, the terrestrial component of the NOM in sediments is more significant. This is reflected in abundant methoxyphenols and a very high carbon preference index. SPM sample from a tributary shows a unique geochemical signature. It contains abundant carboxylic acids, amines, isoprenoids in the pyrolyzate, and is dominated by phytol and 24-methyl-cholesta-5,24(28)-dien-3β-ol in the extract, produced by a diatom bloom. Wax esters with a relatively high proportion of short, methyl-branched alkyl-chains appear together with abundant phytadienes and n-C₁₇ alkane in some samples, suggesting a microbial origin. Anthropogenic OM from runoff and atmospheric deposition was evident from a minor input of polycyclic aromatic hydrocarbons (PAHs) originating from mixed combustion sources. Multivariate analysis using PAH data led us to define simple molecular ratios to distinguish the PAH composition in sand and silty sediments. The newly defined ratios are the alkylated phenanthrenes and anthracenes ratio (APA; C₁-C₃/C₀-C₃ phenanthrenes and anthracenes) and the PAH ring number ratio (RN; 5-6 ring parent PAHs/all parent PAHs). This demonstrates that alkylated, as well as 5-6 ring PAHs are better preserved in the finer than in coarser grained sediments. A ubiquitous, but minor input of petroleum-related contamination with a uniform composition was evident in all samples as revealed by the analysis of petroleum biomarkers. This study demonstrates that the investigation of different classes of riverine OM requires a detailed molecular analysis, applying a series of analytical techniques and adequate statistical data treatment.     

Loss of fish populations from unexploited remote lakes in Ontario, Canada as a consequence of atmospheric fallout of acid

Fish populations in the study lakes were disappearing, primarily as a result of the high acid content of the lakes. As a lake became acidic, the more acid sensitive species ceased reproduction and eventually disappeared. The loss of fish populations resulted both from a long-term lethal effect and from an absence of recruitment of young into the population due to the failure of reproduction. In one of the lakes the acid levels have been high long enough to cause the loss of populations of even the most resistant species.The anomalous concentrations of nickel in the lakes and precipitation; the high concentrations of nickel emitted into the atmosphere in Sudbury, Ontario; the ability of sulfur dioxide to form acid in the atmosphere and fallout in the precipitation over considerable distances from the emission source; the tremendous quantities of sulfur dioxide emitted by industry in Sudbury; the abnormally high concentrations of hydrogen and sulfate ions in the study lakes; all indicated that the emissions from the nickel smelters near Sudbury were the most probable source of contamination that has resulted in the loss of fish stocks from O.S.A., Muriel, and other lakes.     

Effects of Housing Development on Bird Species Diversity in a Forest Fragment in Ontario, Canada

This study investigated the effects of a housing development on the number and composition of forest bird species in an adjacent remnant woodlot in Southern Ontario, Canada. The predicted effects of the development on the woodlot species were the subject of two regulatory hearings between 1979 and 1983. Theoretical evidence was presented that predicted a significant decrease in the number of interior species. The regulatory board ruled that theory was insufficient evidence upon which to predict the effects of the development, and allowed the development to proceed. To measure the effects of the development, a pre-development study undertaken by a consulting firm in 1977 was repeated in 1999, about 10 years after completion of the housing subdivision. The observed number of interior forest specialist species was found to have declined in agreement with prevailing theory, but the observed number of interior-edge and edge generalist species had unexpectedly increased. The results of this study, along with those from other recent studies, have been used to suggest mitigating measures for future developments.     

Landscape Policy and Planning Practice: The gap in understanding,Ontario, Canada

Distortions inevitably occur between the creation of policy and its practical application. The gap that exists between the understanding of landscape held by the policy writers and that of the implementers of land-use planning legislation in Ontario, Canada is revealed. The story is told over a nine-month period between the passing and defeat of one planning act, and the introduction of another. A change of government and a substantive shift in governing ideology resulted in the radical transformation of the policies protecting landscapes in this Canadian province's land-use development process. The research documented took place over that crucial period and gives a window into the dynamics of landscape conservation that is created by upper- and lower-tier differences. Higher-level policy makers have a considerable task in protecting landscapes within land-use planning that demands rational and bounded terminology and processes. Conversely, the local implementers of that policy need more flexible and site-specific strategies to conserve those landscapes on the ground. It is this gap that has stalled the protection of landscapes in Ontario, where governments and communities struggle to conserve their valued landscapes - a phenomenon not uncommon in other locations. Some strategies on how to bridge that gap in understanding and improve the prospects for landscape conservation are given.     

Landscape Policy and Planning Practice: the gap in understanding, Ontario, Canada

Distortions inevitably occur between the creation of policy and its practical application. The gap that exists between the understanding of landscape held by the policy writers and that of the implementers of land-use planning legislation in Ontario, Canada is revealed. The story is told over a nine-month period between the passing and defeat of one planning act, and the introduction of another. A change of government and a substantive shift in governing ideology resulted in the radical transformation of the policies protecting landscapes in this Canadian province's land-use development process. The research documented took place over that crucial period and gives a window into the dynamics of landscape conservation that is created by upper- and lower-tier differences. Higher-level policy makers have a considerable task in protecting landscapes within land-use planning that demands rational and bounded terminology and processes. Conversely, the local implementers of that policy need more flexible and site-specific strategies to conserve those landscapes on the ground. It is this gap that has stalled the protection of landscapes in Ontario, where governments and communities struggle to conserve their valued landscapes - a phenomenon not uncommon in other locations. Some strategies on how to bridge that gap in understanding and improve the prospects for landscape conservation are given.     

Bioreactivity of particulate matter in Beijing air: results from plasmid DNA assay

An in vitro plasmid assay was employed to study the bioreactivity of PM (particulate matter) in Beijing air. It was found that the TD20 (toxic dose of PM causing 20% of plasmid DNA damage) of Beijing PM can be as low as 28 microg ml(-1) and as high as >1000 microg ml(-1). Comparison of the physical properties, such as morphology and size distribution, and oxidative potential indicates that the PM(2.5) (particulate matter with an aerodynamic diameter of 2.5 microm or less) has a stronger oxidative capacity than PM(10) (particulate matter with an aerodynamic diameter of 10 microm or less), and that the higher number percentages of soot aggregates and lower number percentages of mineral and fly ashes are associated with the higher oxidative capacity. Although the mass of PM(10) during dust storms is commonly 5 times higher than that during non-dust storm episodes, the oxidative capacity of PM(10)s of dust storms is much lower than that of the non-dust storm PM(10)s. The water-soluble fractions and intact whole particle solutions of Beijing airborne particles produce similar plasmid assay results, demonstrating that the bioreactivity of Beijing airborne particles is mainly sourced from the water-soluble fraction. In the samples with stronger bioreactivity, the total analyzed water soluble Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As and Pb (ppm) concentrations are higher. The water soluble zinc shows a good negative correlation with TD20s, suggesting that the water-soluble zinc is probably the major element responsible for the plasmid DNA damage.     

Small is Transient: Housebuilding Firms in Ontario,Canada 1978-98

The North American housebuilding industry has been neglected in urban and housing studies. Its firm size structure and instability have long been cause for concern, but have rarely been given more than anecdotal treatment. This paper examines the transience of housebuilders in Ontario from 1978 to 1998. Using a census of builders provided by the Ontario New Home Warranty Program, the industry's firm membership is found to be extremely transient. Most transience comes by way of new firm formation and permanent firm exits from the market, while a small cohort of builders withdraw from and re-enter the market on a regular basis. The business cycle speeds and slows these processes but flux is due primarily to the annual turnover of small builders. To reduce transience, policy makers must decide between slowing entry and perhaps raising industry concentration or allowing continued firm entry and probably transience.     

Experimental investigation on the performance, gaseous and particulate emissions of a methanol fumigated diesel engine

Experiments were conducted on a 4-cylinder direct-injection diesel engine with fumigation methanol injected into the air intake of each cylinder. The fumigation methanol was injected to top up 10%, 20% and 30% of the power output under different engine operating conditions. The effects of fumigation methanol on engine performance, gaseous emissions and particulate emission were investigated. The experimental results show that there is a decrease in the brake thermal efficiency when fumigation methanol is applied, except at the highest load of 0.67 MPa. At low loads, the brake thermal efficiency decreases with increase in fumigation methanol; but at high loads, it increases with increase in fumigation methanol. The fumigation method results in a significant increase in hydrocarbon (HC), carbon monoxide (CO), and nitrogen dioxide (NO(2)) emissions. The concentration of nitrogen oxides (NOx) is significantly reduced except at close to full load condition. There is also a reduction in the smoke opacity and the particulate matter (PM) mass concentration. For the submicron particles, the total number of particles decreases at low and medium loads but increases at high loads. In all cases, there is a shift of the particles towards smaller geometrical mean diameter, especially at high loads. The increase in nano-sized particles and the increase in NO(2) emission could have serious impact on human health.     

Lead in the tissues of terrestrial raptors in southern Ontario, Canada, 1995-2001

Terrestrial raptors which feed on upland hunted game species may increase their risk to lead exposure and lead poisoning by ingesting lead shot found in the tissues of prey. Lead exposure in 225 individuals of nineteen species of terrestrial raptors, collected as carcasses in southern Ontario from 1995-2001, was examined through the analysis of bone, liver and kidney tissues. In this study, one red-tailed hawk contained liver lead concentrations and exhibited signs consistent with lead poisoning. Liver and kidney concentrations of one turkey vulture were also significantly higher than that associated with subclinical effects. This same bird, plus another turkey vulture and a northern harrier, had elevated bone lead concentrations (>10 microg/g dw) associated with possible toxicity. Turkey vultures had the highest mean concentrations of lead in bone and kidney compared to other raptor species. While it appeared only a single bird suffered acute lead poisoning, lead levels exceeded threshold concentrations associated with subclinical or acute toxicity in 4 of 225, almost 2%, of terrestrial raptors assessed. Given the association between lead exposure in raptors and hunting of game species reported in other studies, the continued use of lead shot for upland hunting in Ontario likely remains as one of the primary sources of lead and a continued risk to these birds of prey.     

Chlorophenoxy and chlorobenzoic acid herbicides; their use in eleven agricultural watersheds and their loss to stream waters in Southern Ontario,Canada 1975–1977

A survey in 1975 of eleven agricultural watersheds revealed that chlorophenoxy (CPOA) and chlorobenzoic acid (CBA) herbicides were used for weed control in cereals, corn, peas and beans on farm land and along right-of-ways and other sites on non-agricultural land. These land uses represented 52.6% of the eleven watersheds and 31.8% of this area received treatments of CPOA and CBA herbicides. The quantities and areas treated with chloramben, 2,4-D, 2,4-DB, dicamba, MCPA, mecoprop and 2,4,5-T were documented.Analysis of 949 initial stream waters revealed residues of 2,4-D in sixty-six, 2,4,5-T in twenty-one, MCPA in six and dicamba in one. Losses to stream water were correlated to spray activity adjacent to streams especially where careless use of equipment or material contaminated the water. In addition, storm runoff waters carried herbicide residues to streams, especially when occurring close to the time of application. Spraying of right-of-ways involved spraying of ditch banks with the inevitable contamination of stream water. Losses to water represented 0.03% of agricultural uses and 0.5% of non-agricultural uses. Concentrations found in water were well below currently accepted water quality objectives and therefore posed no known hazard.     

Retrieval of suspended particulate matter concentrations in the Danube River from Landsat ETM data

Alternations in river channel morphology result in a disturbed natural transport of suspended particulate matter (SPM). Suspended particulate matter serves as a transport medium for various pollutants, e.g. heavy metals. It is therefore important to understand how artificial obstructions alter the natural transport of suspended matter. Measurements of SPM in rivers are traditionally carried out during in situ sampling campaigns, which can provide only a limited view of the actual spatial distribution of suspended matter over large distances. Several authors have studied how space-borne remote sensing could be used for mapping of water quality in standing waters, but with only little attention paid to rivers. This paper describes the methodology how a Landsat ETM image was used to map the spatial patterns of SPM in the Slovak portion of the Danube River. Results of our investigation reveal that the Danube River in Slovakia exhibits gradual longitudinal decrease in concentrations of SPM. Based on a strong relationship between the Landsat near-infrared band (TM4) and field measurements, we developed a map of suspended particulate matter in the Danube River with a standard error (SE) of 2.92 mg/L. This study aims to show how archived satellite data and historical water quality data can be used for monitoring of SPM in large rivers. A methodology describing the minimum samples required for sufficiently accurate results is discussed in this paper also.     

Solid state partitioning of trace metals in suspended particulate matter from a river system affected by smelting-waste drainage

The partitioning of particulate trace metals was investigated during one year of monthly sampling of suspended particulate matter (SPM) at eight sites along the Lot-Garonne fluvial system, known for its polymetallic pollution. The chemical partitioning in five operationally defined fractions (exchangeable/carbonate, Fe/Mn oxides, organic matter/sulfides, acid soluble, residual) was determined using a multiple single extraction approach. This approach showed that Cd, Zn, Pb and Cu were mainly associated with acid soluble phases (84-95%, 65-88%, 61-82% and 55-80% of the respective total metal content), and therefore showed a high mean potential of mobilization and bioavailability. In the Riou-Mort River, draining the smelting-wastes, Zn, Cd and Mn showed high mobility as they were little associated with the residual fraction (1-2%) and mainly bound to the 'exchangeable' fraction of SPM (60-80%), probably weakly adsorbed on amorphous freshly-precipitated sulfide and/or oxide phases. Upstream and downstream of the anthropogenic source of metallic pollution, Mn and Cd, and Zn to a lesser extent, remained highly reactive. The other trace metals were mainly associated with the residual fraction and thus less mobile. However, the multiple single extraction scheme revealed that the most reactive transport phases were non-selectively extracted by the conventional extractants used here. These selectivity problems could not have been observed if sequential extraction was used.