Analysis of Long-term Measurements of Airborne Concentrations of Sulphur Dioxide and SO42- in the Rural United Kingdom

During the last two decades, the importance of sulphur dioxide as a pollutant has moved away from its association with suspended particulate matter, to it being a precursor of SO ₄ ^2- aerosol (acidic e.g. sulphuric acid, or neutralised e.g. ammonium sulphate). Co-located concentration data of sulphur dioxide and SO ₄ ^2- , at nine monitoring sites situated in predominantly rural areas in the United Kingdom, collected over the time period 1979–1995, have been analysed. The time series for both species are discussed for the sites. Further analysis has shown that there is a degree of correlation between sulphur dioxide and SO ₄ ^2- for most of the sites considered. This correlation is of approximately the same level for most of the sites taken independently and together, and in most cases the slopes and intercepts associated with the simple empirical model equations arising from the correlation analysis, are of the same order of magnitude. The implementation of these site-dependent model equations within dispersion models for the prediction of the concentration of airborne sulphate aerosol from knowledge of sulphur dioxide concentration is discussed. Furthermore, the correlation analysis revealed the influence of transported sulphate aerosol on the local concentration, especially during high concentration episodes.     

Characterization of Volatile Organic Chemical Emissions From Carpet Cushions

Abstract

The U.S. Consumer Product Safety Commission is investigating chemical emissions from carpet systems in order to determine whether the emissions may be responsible for the numerous health complaints associated with carpet installation. As part of this effort, a study was conducted to identify and quantify volatile organic compounds (VOCs) released into the air by five major product types of new carpet cushions. Cushion samples were tested in small-volume dynamic chambers over a six-hour exposure period. Airborne VOCs collected on multisorbent samplers were identified using sensitive gas chromatography/mass spectrometry. The emissions of selected VOCs were quantitated with the small-scale chamber method and further characterized in larger environmental chambers conducted over a 96-hour period under conditions more representative of indoor environments. A separate chamber method was developed to screen polyurethane cushions for emissions of toluene diisocyanates (TDI). Over 100 VOCs, spanning a broad range of chemical classes, were emitted from 17 carpet cushions. The pattern of emitted VOCs varied between and among product types, which reflects probable differences in manufacturing processes and ingredients. No significant quantities of TDI or formaldehyde were released by any cushions. Emission profiles were characterized for total VOCs and for the predominant individual VOCs. As a group, the synthetic fiber cushion samples emitted the lowest quantities of VOCs. Cushion samples purchased from carpet retailers released lesser amounts of VOCs than samples of the same cushion types obtained directly from the manufacturing mills, suggesting that chemical losses from the bulk material may ensue as a result of transport, handling, and storage prior to installation. The data suggest that placement of carpet on top of a carpet cushion, as would occur in a residential installation, reduced the rate of some VOC emissions when compared to the cushion alone.     

In Situ Velocity Measurements from an Industrial Rotary Kiln Incinerator

Abstract

For the first time, velocities were measured inside a fieldscale rotary kiln incinerator. Combustion gas velocities and temperatures were measured at multiple points across a quadrant of the kiln near its exit using a bidirectional pressure probe and suction pyrometer. To accommodate the new bidirectional probe and gain access to the upper portion of the kiln, a lighter and stiffer positioning boom was designed. The kiln was directly fired using natural gas in a steady state mode. Results indicate strong vertical stratification of both velocity and temperature, with the highest values corresponding to the top of the kiln. Access restraints prevented the lower region of the kiln from being mapped. Horizontal variations in both temperature and velocity were insignificant. Operating conditions were varied by adjusting the amount of ambient air added to the front of the kiln. Increasing the flow of ambient air into the front of the kiln reduced the measured temperatures as expected, but did hot have as significant an effect on measured velocities. The quality of the results is examined by performing mass balances across the incinerator and by comparison to an existing numerical model. Both methods indicate that the experimental results are reasonable.     

Climatic, socio-economic, and health factors affecting human vulnerability to cholera in the Lake Victoria basin, East Africa

Cholera epidemics have a recorded history in the eastern Africa region dating to 1836. Cholera is now endemic in the Lake Victoria basin, a region with one of the poorest and fastest growing populations in the world. Analyses of precipitation, temperatures, and hydrological characteristics of selected stations in the Lake Victoria basin show that cholera epidemics are closely associated with El Ni?o years. Similarly, sustained temperatures high above normal (T(max)) in two consecutive seasons, followed by a slight cooling in the second season, trigger an outbreak of a cholera epidemic. The health and socioeconomic systems that the lake basin communities rely upon are not robust enough to cope with cholera outbreaks, thus rendering them vulnerable to the impact of climate variability and change. Collectively, this report argues that communities living around the Lake Victoria basin are vulnerable to climate-induced cholera that is aggravated by the low socioeconomic status and lack of an adequate health care system. In assessing the communities' adaptive capacity, the report concludes that persistent levels of poverty have made these communities vulnerable to cholera epidemics.     

Speciation of five arsenic species (arsenite, arsenate, MMAAV, DMAAV and AsBet) in different kind of water by HPLC-ICP-MS

A method using Ion Chromatography hyphenated to an Inductively Coupled Plasma-Mass Spectrometer has been developed to accurately determine arsenite (As(III)), arsenate (As(V)), mono-methylarsonic acid (MMAA(V)), dimethylarsinic acid (DMAA(V)) and arsenobetaine (AsBet) in different water matrices. The developed method showed a high sensitivity with detection limits for each arsenic species close to 0.4pg injected. Arsenite and arsenate were the major species found in surface and well waters, but AsBet and DMAA(V) were found in some surface waters, which has never been reported before, while in some natural mineral waters located in volcanic region, the arsenic content exceeded the maximal admissible arsenic content by European legislation standards and the predominant form was As(V).     

Land-Use Planning in the Chaco Plain (Burruyacú, Argentina): Part 2: Generating a Consensus Plan to Mitigate Land-Use Conflicts and Minimize Land Degradation

The Burruyacú district (Tucumán province, Northwest Argentina) has been traditionally an area with rural activities based on the exploitation of the Chaco forest for timber and livestock browsing. Since the 1960s, local institutions started promoting soybean due to favorable land conditions and good market prices. Soybean extension, as from the 1970s, has resulted in important reduction of the Chaco forest and also caused physical soil degradation, especially soil compaction and erosion. A land-use-planning exercise was carried out using the Land-Use Planning and Information System (LUPIS) as a spatial decision support system. LUPIS facilitates the generation of alternative land-use plans by adjusting the relative importance attributed by multiple stakeholders to preference and avoidance policies. The system leads to the allocation of competing land uses to land map units in accordance with their preferred resource requirements, conditional upon the resource base of the area and the stakeholders' demands. After generating a land use plan for each stakeholder category identified in the study area, including commercial farmers, conservative/conventional farmers, and conservationists, a consensus plan was established to address the land-use conflicts between mechanized agriculture, traditional agriculture and forest conservation, and to mitigate soil degradation caused by extensive dry-farming. Although the planning exercise did not directly involve the stakeholders, the results are sufficiently practical and realistic to suggest that the approach could be extended to the entire Chaco plain region.     

Detection of methylquinoline transformation products in microcosm experiments and in tar oil contaminated groundwater using LC-NMR

N-heterocyclic compounds are known pollutants at tar oil contaminated sites. Here we report the degradation of methyl-, and hydroxy-methyl-substituted quinolines under nitrate-, sulfate- and iron-reducing conditions in microcosms with aquifer material of a former coke manufacturing site. Comparison of degradation potential and rate under different redox conditions revealed highest degradation activities under sulfate-reducing conditions, the prevailing conditions in the field. Metabolites of methylquinolines, with the exception of 2-methylquinolines, were formed in high amounts in the microcosms and could be identified by ¹H NMR spectroscopy as 2(1H)-quinolinone analogues. 4-Methyl-, 6-methyl-, and 7-methyl-3,4-dihydro-2(1H)-quinolinone, the hydrogenated metabolites in the degradation of quinoline compounds, were identified by high resolution LC-MS. Metabolites of methylquinolines showed persistence, although for the first time a transformation of 4-methylquinoline and its metabolite 4-methyl-2(1H)-quinolinone is described. The relevance of the identified metabolites is supported by the detection of a broad spectrum of them in groundwater of the field site using LC-NMR technique. LC-NMR allowed the differentiation of isomers and identification without reference compounds. A variety of methylated 2(1H)-quinolinones, as well as methyl-3,4-dihydro-2(1H)-quinolinone isomers were not identified before in groundwater.     

Hydrodynamics of a periodically wind-forced small and narrow stratified basin: a large-eddy simulation experiment

Environmental Fluid Mechanics - We report novel results of a numerical experiment designed for examining the basin-scale hydrodynamics that control the mass, momentum, and energy distribution in a...     

Have international remittance inflows degraded environmental quality? A carbon emission mitigation analysis for Ghana

Environmental Science and Pollution Research - Despite the considerable contributions of remittances to households and economic advancements, their environmental implications have received little...