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Factors Affecting Microbial Degradation of Polycyclic Aromatic Hydrocarbon Phenanthrene in the Caribbean Coastal Water
1999
Zaidi, B.R. | Imam, S.H.
Studies were conducted to assess factors that may influence the rate and extent of biodegradation of polyaromatic hydrocarbons (PAHs) in waters of Guayanilla Bay (latitude, 18°N; longitude, 66.45°W) Puerto Rico. Phenanthrene was used as a model PAHs compound. Both the rate and extent of phenanthrene degradation by natural microbial flora present in seawater samples from Guayanilla Bay were quite slow. Addition of KNO3 as a source of inorganic nitrogen (N) resulted in a 10-fold increase in the rate of phenanthrene degradation within a 125 h period, whereas, addition of K2HPO4 as a source of inorganic nutrient phosphorus (P) had no effect. Phenanthrene degradation was strongly inhibited when seawater pH was adjusted to 10.0. Phenanthrene in seawater samples degraded rapidly when first pretreated with hydrogen peroxide (H2O2) and then inoculated with a known indigenous phenanthrene degrading bacterium, Alteromonas sp. Pretreatment of phenanthrene with Triton-x-100 had little or no effect on its degradation by the same bacteria, whereas, degradation in samples preheated at 60°C was somewhat inhibited.
Afficher plus [+] Moins [-]Storm water pollution control
1999
Dodson, Roy D.
Economics of water pollution
1999
Murty, M. N. (Maddipati Narasimha) | James, A. J. | Miśra, Smitā
This book introduces readers to the theoretical and applied approaches used to control pollution in developing countries. The first of its kind in the Indian context, it investigates the case for using economic instruments to control environmental pollution, especially water pollution arising from industrial production. This book, dealing as it does with both theoretical and empirical issues, will be of interest to students, teachers and researchers of environmental economics as well as policy-makers. Professionals and activists involved in environmental protection will also find it useful.
Afficher plus [+] Moins [-]Response to marine oil pollution
1999
Cormack, Douglas
Air pollution VII | Air pollution 7 | Air pollution seven
1999
Brebbia, C. A. | Jacobson, M. A. | Power, H.
"This book contains over 100 contributions from the Seventh International Air Pollution Conference, held in July 1999. Bringing together recent results from state-of-the-art research projects world-wide, the goal of this meeting was to increase public awareness of air pollution issues and lay the groundwork for further investigations."--BOOK JACKET.
Afficher plus [+] Moins [-]Sources and control of air pollution | Air pollution
1999
Heinsohn, Robert Jennings | Kabel, Robert Lynn
"Students and practitioners alike will find Sources and Control of Air Pollution by Heinsohn and Kabel to be a comprehensive treatment of possible contamination of the atmosphere, the physical and social environment in which it occurs, and the resultant impacts. The cultural, aesthetic, biological, physiological, ecological, legal and economic contexts of air pollution are addressed in depth as are the scientific and engineering principles used to mitigate it."--Jacket.
Afficher plus [+] Moins [-]Photo-Induced OH reactions of naphthalene and its oxidation products on SiO2
1999
Brussol, Claire | Duane, Matthew | Carlier, Patrick | Kotzias, Dimitrios
The photo-induced degradation of naphthalene, 1,4-naphthoquinone, 1-naphthol and 1-NO₂ naphthalene, adsorbed on silica gel, and with the addition of nitrogenous air pollutants e.g. NO₂ (as KNO₂) was investigated. Results indicate that compounds adsorbed onto a solid carrier are degraded when irradiated with UV light (λ > 290 nm) in the presence of nitrites. The key species initiating the naphthalene degradation is the OH-radical which is generated through the photolysis of NO₂. Reaction products identified were 2-formyl-cinnamaldehyde, 1,4-naphthoquinone, nitronaphthol, o-phthaldialdehyde, phthalide and nitronaphthalene. A mass balance between 40–50% was achieved. Under the same irradiation conditions, 1-NO₂ naphthalene is mainly degraded by direct photolysis while degradation of 1-naphthol and 1,4-naphthoquinone proceeds via the reaction with OH-radicals. Identified products were hydroxy-nitro-nitroso- and quinones compounds.
Afficher plus [+] Moins [-]Endocrine disruptors : Status and regulatory aspects
1999
Basler, Armin | Lebsanft, Jörg
Numerous scientific publications have stirred a political debate about the impact of synthetic chemicals on the endocrine system of humans and animals. In an parliamentary inquiry, the Federal Government of Germany was requested to give its opinion on currently available information, to describe the measures taken so far and to outline the challenges for the future.The government’s reply — an abridged, translated version is published here — reviews crucial aspects of the present scientific debate. The main focus is on the critical examination of the request for immediate legal action (e.g. restricting the production or use of certain substances) to reduce exposure to endocrine disruptors. Furthermore, an overview is given on national and international measures taken so far to refine the assessment of the potential hazards emanating from these chemicals, to gain more insight into the underlying biological mechanisms and to improve the basis for targeted and adequate legal action.
Afficher plus [+] Moins [-]Agricultural work related injury and Ill-health and the economic cost
1999
Litchfield, Melville H.
This paper contains a literature review of the occupational injuries and ill-health in agriculture world-wide and a survey of the attempts that have been made to estimate the resulting economic and social costs.Agricultural workers suffer a wide variety of disorders as a result of their occupation. These range from minor (cuts, bruises) to more severe (deep wounds, fractures), permanent (amputation, spinal cord injury) and fatal injury. Ill-health as a result of contact with animals, micro-organisms, plant material dusts or chemicals are associated with certain types of agriculture. There is an underlying but unquantified incidence of pain, stress and injury as a result of ergonomic problems due to poor working procedures and conditions. Statistics from many countries or regions show that agriculture consistently has one of the highest accident and injury rates of the industrial sectors.There are many causes for the work related injury and ill-health in agricultural workers. In developed countries, tractors and other machinery cause a significant proportion of the accidents and are a major cause of occupational deaths. In less developed countries, accidents due to hand tools such as hoes, sickles and cutting instruments are most prevalent. Animals are a significant cause of injury and ill-health in many countries. Debilitating allergic reactions in the respiratory tract or the skin are caused by exposures to organic dusts, or by contact with allergenic plants in the field respectively. Where comparative data are available, occupational pesticide poisoning in agriculture is a small proportion (< 1–4%) of the total work related disorders.Because of the wide variety of occupational risks to agricultural workers, it is emphasised that if one type of agricultural practice is replaced by another then the risks from the alternative procedure need to be considered. If, for example, agrochemical pest control practices are replaced by methods involving the increased use of machinery, draught animals or manual operations, then an assessment of the resulting risks should be taken into account.Some of the economic costs of occupational injury and ill-health in agriculture can be quantified directly, such as medical costs, the cost of rehabilitation and loss of earnings. Other costs are more difficult to estimate such as loss of opportunity and income foregone for permanent and fatal injury and for the effect on a victim’s family. The estimation of the overall economic costs to farming communities and national agriculture requires further development. When one agricultural practice is replaced wholly or partly by another, for example agrochemical pest control by alternative control methods, then it is necessary to take into account the occupational health costs of the alternative procedure for realistic comparative assessment.There are a number of issues which require continued or increased attention by the relevant national and international authorities and by the agricultural industry. These include the improved collection and collation of occupational health statistics, a better understanding of the extent of ergonomic problems in agriculture, more realistic assessments of the cost of occupational injury and ill-health and the continued need to reduce occupational health disorders by appropriate training and education in agricultural practices and the use of agricultural equipment.
Afficher plus [+] Moins [-]Environmental accounting on a communal level: A tool to support environmental management and decision-making by communal executives
1999
Kröger, Gabriele | Pietsch, Jürgen | Ufermann, Kay
Starting from an ecological perspective of urban-industrial areas, environmental accounting is used to analyse and to evaluate which environmental impacts are the result of communal activities (e.g. the results of different kinds of water supply systems). Therefore, the anthropogenic fluxes, the changing quality of areas as well as the processes between the environmental fields are taken into account. The approach is based on methodical elements of te Life Cycle Analysis and the Environmental Impact Assessment.Looking at the ‘urban systems’ within the communal activities, ‘ecological modelling’ gives us a new and fuller picture of the spatial and temporal character of urban metabolism. The approach supports the perception of cumulative effects and the postponement of environmental problems and opens new horizons for process-oriented environmental planning within the community. Greater efficiency and a decrease in costs can be arrived at by leaving ‘end of the pipe’ strategies; opportunities for a better planning process and measures for different individuals and organisations can be drawn up. A data base which acts as a ‘support system’ implements the computer-aided approach to environmental accounting.
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