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At least 919 records · Page 51Linked to original sources
PubMed1999

Factors other than environmental issues influence resource allocation decisions of school foodservice directors.

OBJECTIVE: To identify resource allocation decisions and policies and procedures used by school foodservice directors that were based on the concepts of pollution prevention, product stewardship, and sustainable development. DESIGN: A questionnaire about operational characteristics (including equipment and production systems, menu selection and service style) and environmental issues was mailed to school foodservice directors. SUBJECTS/SETTING: Subjects were school foodservice directors in major cities who were members of the American School Food Service Association. Of the 389 questionnaires mailed, 168 (45.5%) were returned and used for data analysis. STATISTICAL ANALYSIS PERFORMED: Descriptive statistics, analysis of variance, and correlation were used to analyze data. RESULTS: Cost factors were rated more important (P < or = .05) than environmental factors when operational decisions were made. Labor was ranked as the most important future issue by 45.0% of respondents, but it was not the most important factor when current operational decisions were made. Less than 20.0% of the respondents indicated that their districts had specific water (3.3%), energy (14.2%), or solid waste management policies (16.0%). However, 62.6% of respondents stated that their district had a recycling program. APPLICATIONS/CONCLUSIONS: With the exception of recycling programs, school foodservice departments have not adopted a framework of pollution prevention, product stewardship, and sustainable development practices. Recycling and energy conservation programs and use of locally grown food products would minimize the environmental impact of school foodservice operations while reducing operational costs.

Conservation of Natural Resources↗
PubMed1992

Blood lead levels in incinerator workers.

Questions have been raised concerning the safety of mass burn incineration and its role in solid waste management. In 1989, the New York City Office of Occupational Safety and Health examined air levels of metals in New York City incinerators and found that workers were exposed to air lead levels as high as 2500 micrograms/m3 while cleaning the electrostatic precipitators in the plant. In order to determine the biologic significance of these exposures to the workers, blood samples were taken from 56 incinerator workers and 25 controls and analyzed for lead and erythrocyte protoporphyrin levels. Incinerator workers were found to have a mean blood lead of 11.0 micrograms/dl as compared to the control group level of 7.4 micrograms/dl. Risk factors for increased blood lead levels were analyzed using multiple regression analyses. Wearing a personal protective device "always" or not and the interaction of smoking and cleaning the precipitator more than seven times in the past year were found to be significant predictors for blood lead. These results indicate that lead in municipal incinerator ash from electrostatic precipitators is bioavailable and that the effects of such exposure can be minimized by wearing personal protective devices, not smoking, and rotating the work force to minimize precipitator ash contact.

Air Pollutants, Occupational↗
PubMed1999

Agricultural policy and sustainable livestock development.

Future agricultural and rural development is, to a large extent, influenced by the projected food needs of 2.5 billion people expected to swell the world population by 2020. This increase will require more food in general and, in view of recent experience in East Asia, more animal products. To achieve this increase will require judicious use of resources, and trade, especially in those countries where natural resources are insufficient to support food production. Achieving food sufficiency in a sustainable manner is a major challenge for farmers, agro-industries, researchers and governments. The latter play an important role as many of the farmers' choices are, to a large extent, directed by government or supra-government, often through macro- and micro-economic policy. In many countries the economic, environmental, trade and agricultural policies have not been conducive to an agricultural development that is risk-free with respect to the environment, animal welfare or public health. The recent decline of government support in agriculture forced farmers in Western countries to think about more risk adverse agricultural practices and more efficient production systems. On the other hand, many countries in Eastern Europe and the former Soviet Union, as well as other developing countries, are still going through a painful process of adjustment to new market conditions. International banks and development agencies have a mandate to help developing countries, but are somewhat restricted both by needing to work directly with governments and by their perceived dogmatic approach to development. Changing policies do, now and in the future, also affect the development of animal disease control programmes, including the control of parasitic diseases. On the one hand there is an increasing interest in risk-free control practices, and on the other hand a demand for greater regulatory control over the production process. As parasitic diseases of animals are closely linked to the environment (i.e. grazing and waste management) and public health (i.e. parasitic zoonoses), the new interest in sustainable agriculture provides a challenge for those concerned with the control and prevention of animal parasitism.

Agriculture↗
PubMed2003

Quantification and classification of ship scraping waste at Alang-Sosiya, India.

Alang-Sosiya located on the Western Coast of Gulf of Cambay, is the largest ship recycling yard in the world. Every year on average 365 ships having a mean weight (2.10x10(6)+/-7.82x10(5) LDT) are scrapped. This industry generates a huge quantity of solid waste in the form of broken wood, rubber, insulation materials, paper, metals, glass and ceramics, plastics, leather, textiles, food waste, chemicals, paints, thermocol, sponge, ash, oil mixed sponges, miscellaneous combustible and non-combustible. The quantity and composition of solid waste was collected for a period of three months and the average values are presented in this work. Sosiya had the most waste 15.63 kg/m(2) compared to Alang 10.19 kg/m(2). The combustible solid waste quantity was around 83.0% of the total solid waste available at the yard, which represents an average weight of 9.807 kg/m(2); whereas, non-combustible waste is 1.933 kg/m(2). There is not much difference between the average of total solid waste calculated from the sampling data (96.71 MT/day) and the data provided by the port authorities (96.8 MT/day).

India↗
PubMed2001

Anaerobic codigestion of municipal solid waste and biosolids under various mixing conditions--II: Microbial population dynamics.

Microbial population dynamics were evaluated in anaerobic codigesters treating municipal solid waste and sewage sludge. Ribosomal RNA based oligonucleotide probes were used to characterize changes in population abundance of syntrophic volatile fatty acid degrading bacteria and methanogens. Changes in community structure were linked to traditional performance parameters during the recovery of previously unstable codigesters induced by a reduction in mixing levels. Methanosarcina spp. were the most abundant aceticlastic methanogens in unstable codigesters with high acetate concentrations, while Methanosaeta concilii was dominant in stable systems with low levels of acetate. Growth of Syntrophobacter wolinii was enhanced during stabilization of a codigester with a well-developed population of Methanobacteriaceae, possibly because the presence of adequate numbers of these hydrogenotrophic methanogens encouraged the syntrophic oxidation of propionate. Mesophilic saturated fatty acid beta-oxidizing syntrophs were most abundant in previously unstable codigesters. One minimally mixed reactor became unstable after switching to continuously mixed conditions. After the switch, total archaeal abundance decreased sharply, though Methanobacteriaceae and Methanosarcina spp. levels increased as the fermentation became unbalanced. Based on the results presented here, mixing appears to inhibit the syntrophic oxidation of volatile fatty acids, possibly by disrupting the spatial juxtaposition of syntrophic bacteria and their methanogenic partners.

Biomass↗
PubMed2001

Anaerobic codigestion of municipal solid waste and biosolids under various mixing conditions--I. Digester performance.

The feasibility of codigestion of the organic fraction of municipal solid waste, primary sludge, and waste activated sludge was evaluated in mesophilic (37 degrees C), laboratory-scale digesters. In a first experiment, different startup strategies were compared using four digesters, operated under continuously mixed conditions. After two weeks, the experiment was continued under minimally mixed conditions. Results demonstrated that reducing the level of mixing improved digester performance. Therefore, in a second experiment, six digesters were operated to compare performance under continuous mixing and reduced mixing levels at various loading rates and solids levels. The continuously mixed digesters exhibited unstable performance at the higher loading rates, while the minimally mixed digesters performed well for all loading rates evaluated. In a third experiment, it was demonstrated that an unstable, continuously mixed digester was quickly stabilized by reducing the mixing level. These experiments confirmed that continuous mixing was not necessary for good performance and was inhibitory at higher loading rates. In addition, reduction of mixing levels may be used as an operational tool to stabilize unstable digesters.

Oxygen↗
PubMed1998

Dioxin levels in the emissions from municipal waste incinerators in Taiwan.

In this study, characteristics of dioxins emission from existing modern MWIs were evaluated via simultaneous sampling of flue gas and various types of fly ashes. Preliminary results showed that PCDDs congeners distributions were quite similar in flue gas and various types of ashes of both MWIs. PCDFs/PCDDs ratio in cyclone ash was lower than that in combustor ash or fabric filter ash excluding economizer ash of MWI-A. Similarly, PCDFs/PCDDs ratio in ESP ash was lower than that in boiler ash. PCDFs concentration was about 1.5 to 4.3 times higher than PCDDs concentration in flue gas of both MWIs. The mass balance factors of MWI-A (0.9 approximately 1.02) were clearly lower than that of MWI-B (7.71 approximately 15.63), indicating that de novo synthesis occurred under the operating conditions of ESP. In other words, MWIs equipped with ESP were less efficient in controlling PCDD/Fs emissions than that equipped with fabric filters.

Benzofurans↗
PubMed2000

Environmental epidemiology forward.

Environmental epidemiology is the specialized aspect of public health science that studies human health risk from environmental hazards. It is rises largely upon a foundation of public health surveillance, and relies heavily upon analyses of data for small areas and sparse population groups. To a degree, environmental epidemiology is assigned the role of discerning very subtle human health impacts, or discerning early evidence of a tragic sequence. In that context, environmental epidemiology has a substantial public education and risk communication role. Environmental epidemiology will be greatly advanced as effective biological markers of exposure and precursor health effects are developed. At this point in time, statistical methods are in place to monitor population-level disease rates in high-risk populations for early risk identification and sentinel event recognition. Advances in geographic methods have provided a boon to the discipline by advantaging spatial studies. These advances in the discipline still need further refinement and pilot experiences. The inclusion of environmental epidemiological considerations with instances of proposed industrial expansion, hazardous waste management, and contamination remediation is heartily recommended.

Environmental Medicine↗
PubMed1998

The Doñana ecological disaster: contamination of a world heritage estuarine marsh ecosystem with acidified pyrite mine waste.

One of the most important bird breeding and over wintering sites in the west of Europe, the Coto Doñana, was severely impacted by the release of 5 million cubic meters of acid waste from the processing of pyrite ore. The waste entered ecologically sensitive areas of the park (including breeding areas for internationally endangered bird species) causing sustained pH decreases from pH 8.5 to 4.5 and resulting in massive metal contamination of the impacted ecosystem. The contaminating sludge waste contained arsenic at 0.6%, lead at 1.2% and zinc at 0.8% on a dry weight basis. The acid conditions facilitated the solubilization of these metals, leading to water concentrations lethal for aquatic wildlife. The accident caused considerable fish and invertebrate kills and has severe consequences for the protected bird species dependent on the impacted habitats and adjacent areas.

Animals↗
PubMed2002

Novel aquatic modules for bioregenerative life-support systems based on the closed equilibrated biological aquatic system (C.E.B.A.S.).

The closed equilibrated biological aquatic system (C.E.B.A.S) is a man-made aquatic ecosystem which consists of four subcomponents: an aquatic animal habitat, an aquatic plant bioreactor, an ammonia oxidizing bacteria filter and a data acquisition/control unit. It is a precursor for different types of fish and aquatic plant production sites which are disposed for the integration into bioregenerative life-support systems. The results of two successful spaceflights of a miniaturized C.E.B.A.S version (the C.E.B.A.S. MINI MODULE) allow the optimization of aquatic food production systems which are already developed in the ground laboratory and open new aspects for their utilization as aquatic modules in space bioregenerative life support systems. The total disposition offers different stages of complexity of such aquatic modules starting with simple but efficient aquatic plant cultivators which can be implemented into water recycling systems and ending up in combined plant/fish aquaculture in connection with reproduction modules and hydroponics applications for higher land plants. In principle, aquaculture of fishes and/or other aquatic animals edible for humans offers optimal animal protein production under lowered gravity conditions without the tremendous waste management problems connected with tetrapod breeding and maintenance. The paper presents details of conducted experimental work and of future dispositions which demonstrate clearly that aquaculture is an additional possibility to combine efficient and simple food production in space with water recycling utilizing safe and performable biotechnologies. Moreover, it explains how these systems may contribute to more variable diets to fulfill the needs of multicultural crews.

Animals↗
PubMed1997

Mineralization of wastes of human vital activity and plants to be used in a Life Support System.

Available methods for mineralizing wastes of human activity and inedible biomass of plants used in this country and abroad are divided into two types: dry mineralization at high temperatures up to 1270 K with subsequent partial dissolution of the ash and the other--wet oxidation by acids. In this case mineralization is performed at a temperature of 470-460 K and a pressure of 220-270 atmospheres in pure oxygen with the output of mineral solution and dissoluble sediments in the form of scale. The drawback of the first method is the formation of dioxins, CO, SO2, NO2 and other toxic compounds. The latter method is too sophisticated and is presently confined to bench testing. The here proposed method to mineralize the wastes is in mid-position between the thermal and physical chemical methods. At a temperature of 80-90 degrees C the mixture was exposed to a controlled electromagnetic field at normal atmospheric pressure. The method merits simplicity, reliability, produces no dissoluble sediment or emissions noxious for human and plants. The basic difference from the above said methods is to employ as an oxidizer atomic oxygen, its active forms including OH-radicals with hydrogen peroxide as the source. Hydrogen peroxide can be produced with electric power from water inside the Life Support System (LSS).

Biomass↗
PubMed2000

Safe biotechnology 10: DNA content of biotechnological process waste. The Safety in Biotechnology Working Party of the European Federation of Biotechnology.

The adequacy of the existing treatment, disposal and recycling processes of waste streams from biotechnological laboratories and industrial processes, especially those using genetically modified microorganisms, have been repeatedly discussed. Here, we focus on the discussions linked to the DNA content of these wastes, the properties of extracellular (or 'naked') DNA and the ability to transfer genetic information between bacteria (e.g. antibiotic resistances) or into higher organisms.

Bacteria↗
PubMed2001

Biotechnology and the utilization of biowaste as a resource for bioproduct development.

There is widespread concern that increasing concentrations of carbon dioxide and other greenhouse gases in the earth's atmosphere will ultimately lead to climate changes. Recognizing the important role that fossil fuels have in the economies and lifestyles of people throughout the world, it is reasonable to ask if the global economy can be powered in ways that might have less impact on the environment because they discharge less carbon dioxide. A way of addressing this sensitive issue could be through the biodevelopment of biowaste as an alternative and renewable energy resource. Landfilling and incineration are popular ways to deal with biowaste but both cause negative environmental effects such as the use of valuable land and production of dangerous gases. The structural components of cells, cellulose and hemicellulose, make biowaste very susceptible for bioproduct development and biowaste offers biotechnology an opportunity to assist in maintaining environmental quality.

Biotechnology↗
PubMed2002

An overview of small-scale food fermentation technologies in developing countries with special reference to Thailand: scope for their improvement.

Small-scale food fermentation technologies in developing countries have evolved through years of experience rather than through scientific breakthroughs. Many small-scale manufacturers are, therefore, reluctant to accept change and modify fermentation processes. Upgrading the quality and safety of fermented foods, while reducing their production cost and maintaining their authenticity and uniqueness, is of utmost importance. One strategic approach, which has been successfully implemented for the improvement of small-scale soy sauce fermentation in Thailand, is the consortium approach. This approach has allowed industry to work closely in sharing knowledge and common problems, which in turn has provided scientists with the research direction that would best benefit the industry. This consortium approach has brought about changes in the methodologies used in the production of soy sauce, by shortening processing times, introducing fiberglass tanks as bioreactors instead of the traditionally used small earthenware containers and introducing cost-effective waste management systems. One barrier to the application of starter cultures in the small-scale fermentation industry is the loss of uniqueness of fermented products. However, the advent of molecular biology techniques has allowed science to tailor starter cultures to the specific requirements of the manufacturer. Using the techniques of molecular biology, it has been shown that microflora of a specific product vary according to origin and sensory quality. A cell bank is being developed to serve as a resource base for Thai fermented pork sausage in order to facilitate the application of starter cultures in the manufacture of that product.

Developing Countries↗
PubMed1998

The biodegradation of recalcitrant effluents from an olive mill by a white-rot fungus.

Biodegradation of olive-mill wastewater (OMW) was performed by the polyurethane-immobilized mycelium of Lentinula edodes. Throughout three consecutive treatment cycles of the effluent significant abatements of its polluting characteristics were observed. In fact, its contents in total organic carbon, total phenols, total ortho-diphenol were dramatically reduced. In addition, a significant effluent decolorization was evident.

Biodegradation, Environmental↗
PubMed1998

Ethene removal from gas by recycling a water-immiscible solvent through a packed absorber and a bioreactor.

Hydrophobic pollutants in waste gases are difficult to remove with the conventional biological treatment techniques because of the slow gas/water mass transfer rate. A two-stage system with a water-immiscible solvent as intermediate liquid was developed. This system consisted of a packed absorber for transfer of the model pollutant, ethene, from gas to solvent and a stirred-tank reactor (mixer) for solvent/water transfer and subsequent degradation by Mycobacterium parafortuitum. The solvent FC40, a perfluorocarbon, was recycled between these two compartments. The stability of the system was shown during a run of 10 days. The elimination efficiency was found to be a function of the solvent flow: 9% and 15% elimination were obtained at solvent flows of 6 x 10(-8) m3.s-1 and 11.3 x 10(-8) m3.s-1, respectively. Ethene removal remained constant at increasing solvent hold-ups up to 50% (v/v). In spite of the low elimination efficiencies caused by an inefficient use of the column, the feasibility of the system to remove ethene has been demonstrated. The system's performance was described by a steady-state mathematical model. Simulated ethene removal efficiencies agreed well with the experimental data. Based on this, the model was used to optimise the dimensions and operating conditions. Furthermore, the model was used to compare the performance of the combined system (PA/MS) with the performance of a similar system without solvent. It was found that the use of solvent as intermediate liquid can improve substantially the removal efficiency of hydrophobic gaseous pollutants compared with the system without solvent. This is dependent however, on the solubility of the pollutant in the solvent, on the dimensions of the system and on the operating conditions.

Absorption↗
PubMed2001

Tritium and 36Cl as constraints on fast fracture flow and percolation flux in the unsaturated zone at Yucca Mountain.

An analysis of tritium and 36Cl data collected at Yucca Mountain, Nevada suggests that fracture flow may occur at high velocities through the thick unsaturated zone. The mechanisms and extent of this "fast flow" in fractures at Yucca Mountain are investigated with data analysis, mixing models and several one-dimensional modeling scenarios. The model results and data analysis provide evidence substantiating the weeps model [Gauthier, J.H., Wilson, M.L., Lauffer, F.C., 1992. Proceedings of the Third Annual International High-level Radioactive Waste Management Conference, vol. 1, Las Vegas, NV. American Nuclear Society, La Grange Park, IL, pp. 891-989] and suggest that fast flow in fractures with minimal fracture-matrix interaction may comprise a substantial proportion of the total infiltration through Yucca Mountain. Mixing calculations suggest that bomb-pulse tritium measurements, in general, represent the tail end of travel times for thermonuclear-test-era (bomb-pulse) infiltration. The data analysis shows that bomb-pulse tritium and 36Cl measurements are correlated with discrete features such as horizontal fractures and areas where lateral flow may occur. The results presented here imply that fast flow in fractures may be ubiquitous at Yucca Mountain, occurring when transient infiltration (storms) generates flow in the connected fracture network.

Chlorine↗