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Total and methylmercury in sardines Sardinella aurita and Sardina pilchardus from Tunisia
1999
Joiris, C.R. | Holsbeek, L. | Moatemri, N.L. (Laboratory for Ecotoxicology, Free University of Brussels (VUB), Pleinlaan 2, B-1050 Brussels (Belgium))
Long-term bioaccumulation monitoring with transplanted bivalves in the San Francisco Estuary
1999
Gunther, A.J. | Davis, J.A. | Hardin, D.D. | Gold, J. | Bell, D. | Crick, J.R. | Scelfo, G.M. | Sericano, J. | Stephenson, M. (Applied Marine Sciences, Inc., 4749 Bennett Dr., Suite L, Livermore, CA 94550 (USA))
Parasites of sentinel bivalves in the NOAA status and trends program: distribution and relationship to contaminant body burden
1999
Kim YungKul | Powell, E.N. | Wade, T.L. | Presley, B.J. | Sericano, J. (Haskin Shellfish Research Laboratory, Institute of Marine and Coastal Sciences, Rutgers, The State University of New Jersey, 6959 Miller Ave., Port Norris, NJ 08349-3167 (USA))
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 [-]Distribution of volatile organic compounds in Madrid (Spain)
1999
Pérez-Pastor, Rosa María | García-Alonso, Susana | Cabezas, Alberto José Quejido
From November 1995 to October 1996, airborne concentrations of VOCs were measured in the Madrid area to study the organic pollution in general, and the correlation between different pollutants in relation to such parameters as location and season. Mean concentrations for up to 90 compounds were measured at four test sites, including both urban and suburban areas.At the urban sites, maximum concentrations occurred in the autumn and winter, whereas minimum concentrations were reached in summer and spring. Similar changes were obtained for the lesscontaminated site located in the SE of the city, whereas a different pattern was found at the site in the NW of the city due to meteorological aspects. Mean levels of hydrocarbons in Madrid were quite similar to those found in other European cities.Chemometrical techniques were applied to the set of data in order to assess the influence of such factors as traffic, temperature and seasonal variations on the VOC levels.
Afficher plus [+] Moins [-]Aliphatic hydrocarbons in an oil-contaminated soil : Carbon economy during microbiological decontamination
1999
Wibbe, Michael L. | Blanke, Michael M.
Microbial decontamination of hydrocarbon-polluted soil was paralleled with soil respiration measurements. About 1,500 tons of a loamy top soil were found to be contaminated with approximately 2000 mg/kg of aliphatic hydrocarbons, mainly oleic (C18:1) and linoleic acid (C18:2) found in the vicinity of a linoleum manufacturing and then a car dewaxing plant. The contaminated soil was analysed for dry matter, pH, dehydrogenase activity, electrical conductivity and nutrient content viz. nitrate, phosphorus and potassium, as well as a number of indigenous microbes. The soil was low in salt and nutrients. This paper describes the procedure and measures to decontaminate this bulk soil on site from approx. 2,000 to 500 mg of aliphatic hydrocarbons/kg dry matter by use of a nutrient emulsion, indigenous micro-organisms and aeration over 13 months. This 75% reduction in aliphatic hydrocarbons resulted in a concomitant carbon efflux, measured as soil respiration, and was used to calculate carbon fluxes.
Afficher plus [+] Moins [-]Absorption cross-sections of atmospheric constituents: NO2, O2, and H2O
1999
Hermans, Christian | Vandaele, Ann C. | Carleer, Michel | Fally, Sophie | Colin, Réginald | Jenouvrier, Alain | Coquart, Bernard | Mérienne, Marie-France
Absorption spectroscopy, which is widely used for concentration measurements of tropospheric and stratospheric compounds, requires precise values of the absorption cross-sections of the measured species. NO₂, O₂ and its collision-induced absorption spectrum, and H₂O absorption cross-sections have been measured at temperature and pressure conditions prevailing in the Earth’s atmosphere. Corrections to the generally accepted analysis procedures used to resolve the convolution problem are also proposed.
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 [-]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 [-]Identification of oxidized TNT metabolites in soil samples of a former ammunition plant
1999
Bruns-Nagel, Dirk | Schmidt, Torsten C. | Drzyzga, Oliver | Löw, Eberhard v | Steinbach, Klaus
Water extracts of soil samples of the former ammunition plant “Tanne” near Clausthal-Zellerfeld, Lower Saxony, Germany, were investigated for highly polar oxidized 2,4,6-trinitrotoluene (TNT) metabolites. 0.4 to 9.0 mg/kg dry soil 2,4,6-trinitrobenzoic acid (TNBA) and 5.8 to 544 mg/kg dry soil 2-amino-4,6-dinitrobenzoic acid (2-ADNBA) were found. In addition to the oxidized metabolites, TNT, 4- and 2-aminodinitrotoluene (4- and 2-ADNT), and 2,4-dinitrotoluene (2,4-DNT) were extractable with water. Most interestingly, in one sample, 2-ADNBA represented the main contaminant.The origin of the oxidized nitroaromatics is unknown at this time. They might be generated chemically or photochemically. Furthermore, a biological synthesis seems possible.
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