Chemicals in Household Products: Problems with Solutions

The success of a regulatory regime in decreasing point-source emissions of some harmful chemicals has highlighted the significance of other sources. A growing number of potentially harmful chemicals have been incorporated into an expanding range of domestic household products and are sold worldwide. Tighter regulation has been proposed, and the European Commission has introduced the Regulation on the Registration, Evaluation, and Authorisation of Chemicals to address this concern. However, it is clear that in addition to the regulation, there is a potential to effect change through retailer and consumer attitudes and behaviours. Interviews were conducted with 7 key stakeholder groups to identify critical issues, which were then explored using a public survey questionnaire (1,008 respondents) and 8 subsequent focus groups. The findings demonstrated that the issue of chemicals in products is of concern to consumers for reasons of personal health rather than environmental protection. Key obstacles to the wider purchase of “green-alternative” products included perceived high cost and poor performance, lack of availability of products, and poor information concerning such products. Although improved regulation was seen as part of the solution, consumers must also play a role. It was clear from this study that consumers are not currently able to make informed choices about the chemicals they use but that they would be receptive to moving toward a more sustainable use of chemicals in the future if empowered to do so.     

Improving the effectiveness of angular dispersion in plant neighbourhood models

Spatial arrangement can be an important factor affecting competition among plants. We evaluated three ways to improve the effectiveness of angular dispersion (AD) for describing spatial arrangement in plant neighbourhood models. First, we modified Zar's (1974) AD formula by weighting each neighbour by its competitive influence. We calculated this using two different competition indices to derive an AD of competitive influence, rather than of equally weighted plant locations, around a subject plant. Secondly, we constrained the effect of AD on the neighbourhood model using an optimised parameter that defines the minimum value that AD can adopt. Thirdly, we included the direction in which competition is concentrated (the mean azimuth of the weighted AD) in the growth models. These developments were evaluated within a radial growth model of Scots pine and birch growing in semi-natural, spatially heterogeneous forest. Weighted AD resulted in significant improvements in predicted radial growth of target trees over the traditional measure of AD. The optimised parameter that defines the minimum value of AD consistently evolved values significantly higher than zero. This suggests that clumped and dispersed neighbourhoods do not differ in their negative effects on a subject tree as much as expected. The inclusion of directional components of the weighted AD did not improve the accuracy of the growth models. Weighting of the angular dispersion of neighbours improved the performance of local competition models.     

Recording the Response of Plants to Various Air Pollutants

A discussion of the methods used to determine the most economic design of chimney for a new thermal power station or large industrial plant is presented, with the objective that ground level concentration of pollutants will be kept at a minimum. Attention is paid to the geography and climatology of the site, with special reference to the frequency and height of inversions and the prevailing wind direction and speed.

A method is illustrated in using a large thermal power station as an example. The maximum sulfur dioxide concentrations at ground level are computed for several chimney heights and gas exit velocities. The values of these sulfur dioxide concentrations, the capital cost of the chimney, the pumping costs, and the gas pressures within the chimney are considered in selecting a suitable chimney height and a gas exit velocity which will meet most economically the stated objective.

The paper deals primarily with chimneys for industrial or power boiler plant of maximum continuous rating greater than 450 million Btu/hr (about 450,000 lbs of steam/hr), or to chimneys serving furnaces burning fuel at a maximum rate greater than 50,000 lbs/hr of coal, or 80,000 lbs/hr of oil. For chimneys serving plant with smaller heat inputs, chimney selection by reference to Clean Air Act 1956, Memorandum on Chimney Heights is suggested.     

URBANIZATION INFLUENCES ON AQUATIC COMMUNITIES IN NORTHEASTERN ILLINOIS STREAMS1

ABSTRACT: Biotic indices and sediment trace element concentrations for 43 streams in northeastern Illinois (Chicago area) from the 1980s and 1990s were examined along an agricultural to urban land cover gradient to explore the relations among biotic integrity, sediment chemistry, and urbanization. The Illinois fish Alternative Index of Biotic Integrity (AIBI) ranged from poor to excellent in agricultural/rural streams, but streams with more than 10 percent watershed urban land (about 500 people/mi²) had fair or poor index scores. A macroinvertebrate index (MBI) showed similar trends. A qualitative habitat index (PIBI) did not correlate to either urban indicator. The AIBI and MBI correlated with urban associated sediment trace element concentrations. Elevated copper concentrations in sediment occurred in streams with greater than 40 percent watershed urban land. The number of intolerant fish species and modified index of biotic integrity scores increased in some rural, urbanizing, and urban streams from the 1980s to 1990s, with the largest increases occurring in rural streams with loamy/sandy surficial deposits. However, smaller increases also occurred in urban streams with clayey surficial deposits and over 50 percent watershed urban land. These data illustrate the potentially complex spatial and temporal relations among biotic integrity, sediment chemistry, watershed urban land, population density, and regional and local geologic setting.     

Carbon accounting model for forests in Australia

CAMFor (Carbon Accounting Model for Forests) is a sophisticated spreadsheet model developed to assist in carbon accounting and projection. This model can integrate information from a range of alternate sources including user input, default parameters and third party model outputs to calculate the carbon flows associated with a stand of trees and the wood products derived from harvests of that stand. Carbon is tracked in the following pools: * Biomass (stemwood, branches, bark, fine and coarse roots, leaves and twigs) * Soil (organic matter and inert charcoal) * Debris (coarse and fine litter, slash, below ground dead material) * Products (waste wood, sawn timber, paper, biofuel, reconstituted wood products). These pools can be tracked following thinning, fires and over multiple rotations. A sensitivity module has been developed to assist examination of the important assumptions and inputs. This paper reviews the functionality of CAMFor and reports on its use in a case study to explore the precision of estimates of carbon sequestration in a eucalypt plantation. Information on variability in unbiased models, measurement accuracy and other sources of error are combined in a sensitivity analysis to estimate the overall precision of sequestration estimates.     

Characterisation of airborne particles collected within and proximal to an opencast coalmine: South Wales,U.K

Airborne particulate matter has been collected from within,and proximal to, an opencast coal mine in south Wales. Thiswork forms the first part of a three year project to collectand characterise, then determine the possible toxicology ofairborne particles in the south Wales region. High-resolutionField Emission SEM has shown that the coal mine dusts consistlargely of an assemblage of mineral grains and vehicle exhaustparticles. SEM-EDX has shown that the mineralogical make-up ofthe PM10 is complex, heterogeneous, and constantly changing.These findings are supported by analytical TEM-EPXMA.However, patterns can be determined relating the mineralogicalcomposition of the airborne particles to collection locationsand mining activities within the opencast. At our studyopencast, Park Slip West, quartz, which has known healtheffects, never exceeded 30% of the total collection mass, andaverage levels were much less. Vehicle exhaust emissions wasthe largest source in terms of particle numbers. The mass ofairborne particulate matter within the pit averagedapproximately twice that of outside the pit: importantlyhowever, this higher mass was due to relatively large, andnon-respirable, mineral grains. This study demonstrates that the physicochemical andmineralogical characterisation of airborne particles frommining and quarrying is essential to quantify the respirablefraction, and to identify potentially hazardous componentswithin the PM10.     

Reproduction and development of the polychaete Stauronereis rudolphi,including a summary of development in the superfamily Eunicea

The life history of the dorvilleid polychaete Stauronereis rudolphi (Delle Chiaje) was studied through the F₂ generation under laboratory conditions. The species released its gametes into the water where fertilization occurred. The pelagic larvae swam for one week before settling. Segments were added successively and sexual maturity was reached in one year of laboratory culture. Spawned adults recovered and began feeding a few days after spawning. The culture techniques and foods used to rear developing eggs, larvae, juveniles, and adults were described. Comparisons were made with other developmental studies in the superfamily Eunicea.This study was a portion of a thesis submitted in partial fulfillment of the requirements for the degree of Master of Arts in the Department of Biology, California State College at Long Beach. It was in part supported by research grant WP-00531-02 from the National Institute of Health, U. S. Public Health Service, under supervision of Dr. Donald J. Reish. Contribution No. 1 of the Ira C. Darling Center for Research, Teaching and Service, University of Maine, Maine 04573, U.S.A.