Critical review of industrial and medical waste practices in Dar es Salaam City

Industrial and medical wastes constitute a larger part on what is known as ‘hazardous wastes’. The production of these wastes is and will continue to be an on going phenomenon as long as human civilization persists. The health impacts of direct and indirect exposure to hazardous wastes include carcinogenic effects, reproductive system damage, respiratory effects, central nervous system effects, and many others. Today, many developed countries have legal provisions with regard to proper management of hazardous wastes. Tanzania, like many developing countries, has little emphasis on the proper handling and disposal of hazardous wastes. There is a serious inadequacy in handling industrial and medical solid wastes in the Dar es Salaam City. Improper waste deposition is increasingly becoming a potential public health risk and an environmental burden. Due to poor control of waste, industrialists and hospital owners are not well checked on how they handle and dispose of the wastes they produce with the result that many hazardous wastes reach the Vingunguti dumpsite without notice. Data on waste generation in Dar es Salaam is also inadequate, making it difficult to plan an efficient solid waste system. Promotion of public awareness, legislation and regulations enforcement and establishment of a proper sanitary landfill are considered to be principal remedial measures to ensure sound environmental maintenance. This paper summarizes the findings of the study on the practices of industrial and medical waste management in Dar es Salaam. The author aims to express the inadequacy in hazardous waste management and suggests possible measures to be applied in order to rectify the situation.     

Hazardous wastes transboundary movement management: a case study in Taiwan

More than 50,000 tons of hazardous waste are imported and exported worldwide each year. Over 50% of hazardous waste is exported to Southeast Asia, of which leather waste is the major component. The exportation quantities of hazardous waste to Organization of Economic Cooperation and Development (OECD) countries are decreasing while they are on the increase to non-OECD countries. Some of these wastes are intended for recycling purposes but the usage of some others is not stipulated. The hazardous waste importation quantity kept fairly steady from 1997 to 2000, of which ash or residues containing copper or copper compounds were the major component. Under existing regulations and measures, the transboundary movement of hazardous waste cannot be effectively controlled and monitored. In order to ensure environmentally sound hazardous waste management, EPA-Taiwan revised the Waste Disposal Act in 2001 and cooperated with the Industrial Development Bureau (IDB) to promote industrial waste reduction and recycling projects. Strategies were proposed based on evaluation according to the 3Es Principles and the site investigation in this study.     

发达国家和地区危险废物名录管理实践

危险废物名录制度是危险废物环境管理的基础。2016年6月14日,环境保护部、国家发改委、公安部联合公布了《国家危险废物名录》(2016年版),对2008年版危险废物名录进行了调整。本文介绍了主要发达国家和地区危险废物名录制度的基本情况,对其优缺点进行了对比分析,以期为更好的理解新版危险废物名录提供参考。主要发达国家和地区的危险废物名录管理体系具有以下优点:一是完善的危险废物豁免排除制度加强了企业和管理部门的责任意识。二是危险废物和一般固体废物共享分类体系便于对废物的统筹管理,废物代码内容翔实,增加了名录的可操作性。三是基于不同处理责任主体进行分类,避免了名录方式或列举方式造成的"漏分"现象。四是根据环境风险实行分级管理,重点突出。同时存在几点不足:一是鉴别程序繁琐,降低了危险废物处置效率;二是存在部分行业产生的废物遗漏、同类危险废物分类过细等问题;三是部分国家危险废物分类过于笼统,不利于企业对危险废物种类及属性的识别。     

An Expert System for Waste Management

Management of hazardous waste is an increasing problem for both the companies that generate the waste and for the communities that eventually experience the consequences of the management decisions. Thus, both social and political aspects must be considered when solving these problems. It is thus important that waste management technologies are evaluated by a panel of experts with various backgrounds. The methodology for developing an expert system for waste treatment technology evaluation was discussed. An expert system was developed to select the “best” waste treatment alternatives. This expert system includes two different knowledge bases: one for the economic and technical parts of the problem and another for the social and political aspects. This expert system was developed on an IBM personal computer using Turbo Prolog™. The pulp and paper industry was selected as an example problem for developing this expert system, which system was tested using two example waste streams from the pulp and paper industry. The results agree with the current treatment facilities the companies are using.     

A new system for groundwater contamination hazard rating of landfills

In developing countries, several unregulated landfills exist adjacent to large cities, releasing harmful contaminants to the underlying aquifer. Normally, landfills are constructed to hold three types of waste, namely hazardous waste, municipal solid waste, and construction and demolition waste. Hazardous waste and municipal solid waste landfills are of greater importance as these pose greater hazard to groundwater, in comparison with landfills holding waste from construction and demolition. The polluting landfills need to be prioritized to undertake necessary control and remedial measures. This paper assesses existing site hazard rating systems and presents a new groundwater contamination hazard rating system for landfills, which can be used for site prioritization. The proposed system is based on source-pathway-receptor relationships and evaluates different sites relative to one another. The system parameters have been selected based on literature. The Delphi technique is used to derive the relative importance weights of the system parameters. The proposed system is compared with nine existing systems. The comparison shows that the site hazard scores produced by the existing systems for hazardous waste, municipal solid waste, and construction and demolition waste landfills are of the same order of magnitude and tend to overlap each other but the scores produced by the proposed system for the three types of landfills vary almost by an order of magnitude, which shows that the proposed system is more sensitive to the type of waste. The comparison further shows that the proposed system exhibits greater sensitivity also to varied site conditions. The application of different systems to six old municipal solid waste landfills shows that whereas the existing systems produce clustered scores, the proposed system produces significantly differing scores for all the six landfills, which improves decision making in site ranking. This demonstrates that the proposed system makes a better tool for prioritization of landfills for adopting control measures and remediation.     

基于GIS技术的重庆市危险废物管理信息系统研究

重庆市每年都会产生大量的危险废物，直接威胁到了重庆市的水环境及生态环境，因此，有效的管理重庆市的危险废物是处理和处置的重要保证。主要介绍了基于CIS危险废物管理信息系统的设计，将危险废物、计算机技术和GIS技术相结合，为危险废物的管理提供快捷、方便、科学的管理和决策支持。该系统包括六个子系统，分别是数据输入、数据查询、数据库管理和维护、模型库、决策支持、系统管理。该系统具有界面友好、操作方便、实用等特点，将在重庆市危险废物管理方面起到重要作用。     

Overview of Environmental Hazards and Health Effects of Pollution in Developing Countries: A Case Study of Nigeria

Pollution has taken on a global dimension, and the effects are most obvious in developing countries. The effects take a toll on human health, animals, and vegetation, as well as on soil, air, and water quality. The objective of this article is to discuss the current relationships among pollution, environmental quality, and human health within the frame of anthropogenic activities in developing countries. In addition to personal observations, we review relevant literature on conditions throughout the developing world and case studies on conditions and activities in Nigeria. Key findings show the significant, adverse contributions to human health and environmental risk from current waste generation and handling practices, indoor and outdoor air pollution, wastewater and effluent generation and disposal, the hazardous nature and pollution potential of wastes, and the human behaviors that contribute to pollution in developing countries. There is an urgent need to create awareness among the various segments of society of the human health hazards posed by pollution as well as a need for the comprehensive development and enforcement of appropriate policies to prevent a descent into an abyss of deteriorating human and environmental health.     

A Paradigm of International Environmental Law: The Case for Controlling the Transboundary Movements of Hazardous Wastes

The production of large quantities of wastes globally has created a commercial activity involving the transfrontier shipments of hazardous wastes, intended to be managed at economically attractive waste-handling facilities located elsewhere. In fact, huge quantities of hazardous wastes apparently travel the world in search of “acceptable” waste management facilities. For instance, within the industrialized countries alone, millions of tonnes of potentially hazardous waste cross national frontiers each year on their way for recycling or to treatment, storage, and disposal facilities (TSDFs) because there is no local disposal capacity for these wastes, or because legal disposal or reuse in a foreign country may be more environmentally sound, or managing the wastes in the foreign country may be less expensive than at home. The cross-boundary traffic in hazardous wastes has lately been under close public scrutiny, however, resulting in the accession of several international agreements and laws to regulate such activities. This paper discusses and analyzes the most significant control measures and major agreements in this new commercial activity involving hazardous wastes. In particular, the discussion recognizes the difficulties with trying to implement the relevant international agreements among countries of vastly different socioeconomic backgrounds. Nonetheless, it is also noted that global environmental agreements will generally be a necessary component of ensuring adequate environmental protection for the world community—and thus a need for the careful implementation of such agreements and regulations.     

Estimating maquiladora hazardous waste generation on the U.S./Mexico border

Maquiladoras, manufacturing plants that primarily assemble foreign components for reexport, are located in concentrations along the northern frontier of the US/Mexico border. These plants process a wide variety of materials using modern industrial technologies within the context of developing world institutions and infrastructure. Hazardous waste generation by maquiladoras represents a critical environmental management issue because of the spatial concentration of these plants in border municipalities where the infrastructure for waste management is nonexistent or poor. These border municipalities contain rapidly increasing populations, which further stress their waste handling infrastructure capacities while exposing their populations to greater contaminant risks. Limited empirical knowledge exists concerning hazardous waste types and generation rates from maquiladorsas. There is no standard reporting method for waste generation or methodology for estimating generation rates at this time. This paper presents a method that can be used for the rapid assessment of hazardous waste generation. A first approximation of hazardous waste generation is produced for maquiladoras in the three municipalities of Nogales, Sonora, Mexicali, Baja California, and Cd. Juarez, Chihuahua, using the INVENT model developed by the World Bank. In addition, our intent is to evaluate the potential of the INVENT model for adaptation to the US/Mexico border industrial situation. The press of border industrial development, especially with the recent adoption of the NAFTA, make such assessments necessary as a basis for the environmental policy formulation and management needed in the immediate future.     

Hazardous waste indicators for national decision makers

Indicators and indices are important tools that assist decision makers to formulate and implement plans for management at local, national and international levels. Four indicators for hazardous waste management are described that have recently been adopted within the United Nations framework of Indicators of Sustainable Development. Although these four indicators will be useful tools, the need for a broader range of policy-relevant qualitative and quantitative indicators, proxy indicators and indices is outlined. The argument is advanced that in order for all nations to better manage the range of hazardous waste issues, including waste generation, export/import and disposal, a set of innovative indicators and indices is required. Useful indicators and indices are described that could be used to link and quantify likely environmental, ecosystem and health impacts and risks especially from hazardous waste disposal. Indicators are also suggested that could be used to illustrate the shift in industrial strategy away from end-of-pipe processes towards waste recycling, cleaner production and integrated life-cycle analysis. It was concluded that until the lack of reliable and harmonized data on hazardous waste is addressed, indicator development and use by national and international decision makers cannot readily be implemented.     

沥青废气燃烧处理技术

在不同温度、不同沥青废气与天然气混合比及不同催化剂的条件下,用燃烧法对沥青熔化中产生的废气进行处理,研究其最佳处理效果,降低沥青废气排放浓度和废气中有害物质的浓度,解决了沥青废气严重污染环境的问题。     

Management of urban solid waste: Vermicomposting a sustainable option

Solid waste management is a worldwide problem and it is becoming more and more complicated day by day due to rise in population, industrialization as well as changes in our life style. Presently most of the waste generated is either disposed of in an open dump in developing countries or in landfills in the developed ones. Landfilling as well as open dumping requires lot of land mass and could also result in several environmental problems. Land application of urban/municipal solid waste (MSW) can be carried out as it is rich in organic matter and contains significant amount of recyclable plant nutrients. The presence of heavy metals and different toxics substances restricts its land use without processing. Vermicomposting of MSW, prior to land application may be a sustainable waste management option, as the vermicast obtained at the end of vermicomposting process is rich in plant nutrients and is devoid of pathogenic organism. Utilization of vermicast produced from urban/municipal solid waste in agriculture will facilitate in growth of countries economy by lowering the consumption of inorganic fertilizer and avoiding land degradation problem. Vermicomposting of urban/MSW can be an excellent practice, as it will be helpful in recycling valuable plant nutrients. This review deals with various aspects of vermicomposting of MSW.     

Should tobacco products’ waste be considered as hazardous in India?

Tobacco and its associated products are known to be harmful for health. Moreover, the waste emanating out of the production, processing, packaging, and consumption of these products is equally harmful for humans as well as other biotic/abiotic agencies. Taking into account the toxic nature of these waste products, it is necessary to have a well-defined approach to deal with this waste. Consideration of tobacco products’ waste as municipal solid waste has serious implications in the long-term as it results in dumping of these wastes mixed-up with domestic waste in landfills. With time, toxic components become part of the leachate which contaminates water and soil, further leading to the contamination in food chain. Therefore, many countries are now considering this waste under the hazardous category and evolving various measures to safely dispose it off. In the light of recent researches and policies, it is time to re-consider this important public health issue.     

Chemical Warfare Materiel: Unique Regulatory Issues

In those states that have not included CWM as hazardous materials in their RCRA programs, the RCRA requirements for management of hazardous waste would not strictly apply to any of the CWM. The Army has historically implemented procedures requiring that chemical warfare agents be managed as RCRA hazardous waste regardless of the concentration, physical form, or configuration of the agent. Such application of strict hazardous waste requirements to management of potentially nonhazardous CWM can result in remedial costs well out of proportion to potential human health and environmental benefits. Recent development of chronic toxicity values for the CWM has opened the door for development of cleanup and waste management standards for waste streams or media containing small residual amounts of CWM. Implementation of this health-based approach to management of CWM remediation wastes may, in part, help to reduce potentially unnecessary hazardous waste management costs for the nonhazardous CWM.     

Rapid population growth and environmental degradation: ultimate versus proximate factors

This philosophical review of 2 arguments about responsibility for and solutions to environmental degradation concludes that both sides are correct: the ultimate and the proximal causes. Ultimate causes of pollution are defined as the technology responsible for a given type of pollution, such as burning fossil fuel; proximate causes are defined as situation-specific factors confounding the problem, such as population density or rate of growth. Commoner and others argue that developed countries with low or negative population growth rates are responsible for 80% of world pollution, primarily in polluting technologies such as automobiles, power generation, plastics, pesticides, toxic wastes, garbage, warfaring, and nuclear weapons wastes. Distortionary policies also contribute; examples are agricultural trade protection, land mismanagement, urban bias in expenditures, and institutional rigidity., Poor nations are responsible for very little pollution because poverty allows little waste or expenditures for polluting, synthetic technologies. The proximal causes of pollution include numbers and rate of growth of populations responsible for the pollution. Since change in the ultimate cause of pollution remains out of reach, altering the numbers of polluters can make a difference. Predictions are made for proportions of the world's total waste production, assuming current 1.6 tons/capita for developed countries and 0.17 tons/capita for developing countries. If developing countries grow at current rates and become more wealthy, they will be emitting half the world's waste by 2025. ON the other hand, unsustainable population growth goes along with inadequate investment in human capital: education, health, employment, infrastructure. The solution is to improve farming technologies in the 117 non-self-sufficient countries, fund development in the most unsustainable enclaves of growing countries, break institutionalized socio-political rigidity in these enclaves, and focus on educating and empowering women in these enclaves. Women are in charge of birth spacing and all aspects of management of energy, food, water and the local environment, more so than men, in most countries.     

基于多模态感知的危险废物环境风险评估与预警研究

为了有效地防范化解危险废物的环境风险,亟须构建风险的精细化评估与实时智能预警系统。然而,危险废物特性复杂、全过程流转链条长,传统的单一感知数据并不能满足环境风险评估和预警的需求。因此,本文提出基于多模态感知的危险废物环境风险评估与预警方法,采用物联网、大数据、人工智能等技术手段,实现危险废物基础信息、环境要素、空间信息的多模态实时感知,并通过感知信息的融合、分析,进行准则判断或现象描述。围绕以上研究思路,本文针对危险废物贮存环节及非法倾倒两个重要风险因子释放情景,设计了基于多模态感知的风险评估与预警方法,以期为危险废物环境风险的管控提供相应的服务与决策。     

我国废铅酸蓄电池污染防治技术及政策探讨

废铅酸蓄电池回收环节产生的废渣、铅酸污泥等属于危险废物,必须按照危险废物进行管理;而废铅酸蓄电池铅回收过程也会产生二次污染,其生产过程和管理不当会产生严重的环境污染。本文在分析我国再生铅生产工艺技术现状、废铅酸蓄电池资源再生过程污染源的基础上,对废铅酸蓄电池资源再生过程污染源治理和污染预防措施以及目前废铅酸蓄电池铅回收相关政策和管理要求进行了较为系统的分析和总结。     

Hazardous waste sites,stress, and neighborhood quality in USA

Summary Seven neighborhoods adjacent to hazardous waste were surveyed. The authors found that respondents did not rate their neighborhoods as highly as Americans as a whole, but, like most Americans, they did rate their present neighborhood better, or the same as, their previous one. The adjacent hazardous waste site was mentioned as distressing more often than any other neighborhood characteristic. Yet in four of the seven neighborhoods, dilapidated buildings and streets, odors and smoke from sewage treatment plants and factories, noise from trains and traffic congestion, or another neighborhood characteristic was mentioned as more stressful than the hazardous waste site. It is argued that govemment needs to be more aggressive about understanding community viewpoints before proposing multi-million dollar hazardous waste remediation plans that could be resisted by a community.Professor Michael Greenberg and Dr Dona Schneider are regular contributors to this Journal. All three authors work in the Department of Urban Studies and Community Health, and support the New Jersey Graduate Program in Public Health at Rutgers University.     

基于人工神经网络模型预测2017~2018年成都市危险废物增量研究

危险废物对环境或者人体健康会造成有害影响,有效地预测其产量是优化管理和合理处置的重要依据。以2008~2016年成都市危险废物产生量为基础,通过数据带入和整合及综合各参数因子的影响,利用人工神经网络模型预测方法客观反映并预测成都市危废产量的变化趋势。结果表明该模型预测2017~2018年成都市危险废物年产量分别达到24.46万t和26.88万t,模拟精度偏差低。因此,人工神经网络模型可以作为一种预测危险废物产生量的工具,其预测结果可以为职能部门提供决策参考。     

辽宁省危险废物排放现状与污染控制战略

结合辽宁省危险废物排放现状，提出辽宁省危险废物污染控制战略。建立全省危险废物管理与登记交换中心，建设省级危险废物安全填埋处置中心、危险废物焚烧中心、省级危险废物污染事故预警系统。提出全省医疗废物处置设施建设布局和技术路线选择方案、硼泥和铬渣处置技术路线。在大城市或经济较发达城市，可采取回转炉方法集中焚烧医疗废物，而运输半径之外偏远山区或经济欠发达城市可采用高温灭菌方法处置本辖区内的医疗废物。硼泥、铬渣则优先采用资源化技术进行处置。