File Name: types of pollution causes and prevention .zip
Jerry Spiegel and Lucien Y. Over the course of the twentieth century, growing recognition of the environmental and public health impacts associated with anthropogenic activities discussed in the chapter Environmental Health Hazards has prompted the development and application of methods and technologies to reduce the effects of pollution.
In this context, governments have adopted regulatory and other policy measures discussed in the chapter Environmental Policy to minimize negative effects and ensure that environmental quality standards are achieved. The objective of this chapter is to provide an orientation to the methods that are applied to control and prevent environmental pollution. The basic principles followed for eliminating negative impacts on the quality of water, air or land will be introduced; the shifting emphasis from control to prevention will be considered; and the limitations of building solutions for individual environmental media will be examined.
It is not enough, for example, to protect air by removing trace metals from a flue gas only to transfer these contaminants to land through improper solid waste management practices. Integrated multimedia solutions are required. The environmental consequences of rapid industrialization have resulted in countless incidents of land, air and water resources sites being contaminated with toxic materials and other pollutants, threatening humans and ecosystems with serious health risks.
More extensive and intensive use of materials and energy has created cumulative pressures on the quality of local, regional and global ecosystems. Before there was a concerted effort to restrict the impact of pollution, environmental management extended little beyond laissez-faire tolerance, tempered by disposal of wastes to avoid disruptive local nuisance conceived of in a short-term perspective.
The need for remediation was recognized, by exception, in instances where damage was determined to be unacceptable. As the pace of industrial activity intensified and the understanding of cumulative effects grew, a pollution control paradigm became the dominant approach to environmental management.
Under the pollution control approach, attempts to protect the environment have especially relied on isolating contaminants from the environment and using end-of-pipe filters and scrubbers. These solutions have tended to focus on media-specific environmental quality objectives or emission limits, and have been primarily directed at point source discharges into specific environmental media air, water, soil. Application of pollution control methods has demonstrated considerable effectiveness in controlling pollution problems - particularly those of a local character.
Application of appropriate technologies is based on a systematic analysis of the source and nature of the emission or discharge in question, of its interaction with the ecosystem and the ambient pollution problem to be addressed, and the development of appropriate technologies to mitigate and monitor pollution impacts.
In their article on air pollution control, Dietrich Schwela and Berenice Goelzer explain the importance and implications of taking a comprehensive approach to assessment and control of point sources and non-point sources of air pollution. They also highlight the challenges - and opportunities - that are being addressed in countries that are undergoing rapid industrialization without having had a strong pollution control component accompanying earlier development.
Marion Wichman-Fiebig explains the methods that are applied to model air pollutant dispersion to determine and characterize the nature of pollution problems. This forms the basis for understanding the controls that are to be put into effect and for evaluating their effectiveness. As the understanding of potential impacts has deepened, appreciation of effects has expanded from the local to the regional to the global scale.
Hans-Ulrich Pfeffer and Peter Bruckmann provide an introduction to the equipment and methods that are used to monitor air quality so that potential pollution problems can be assessed and the effectiveness of control and prevention interventions can be evaluated.
John Elias provides an overview of the types of air pollution controls that can be applied and the issues that must be addressed in selecting appropriate pollution control management options. Preul explains the manner in which discharges are received in water bodies, and may be analysed and evaluated to assess and manage risks.
Finally, an overview is provided of the techniques that are applied for large-scale wastewater treatment and water pollution control. A case study provides a vivid example of how wastewater can be reused - a topic of considerable significance in the search for ways that environmental resources can be used effectively, especially in circumstances of scarcity. Alexander Donagi provides a summary of the approach that has been pursued for the treatment and groundwater recharge of municipal wastewater for a population of 1.
Under the pollution control perspective, waste is regarded as an undesirable by-product of the production process which is to be contained so as to ensure that soil, water and air resources are not contaminated beyond levels deemed to be acceptable. Lucien Maystre provides an overview of the issues that must be addressed in managing waste, providing a conceptual link to the increasingly important roles of recycling and pollution prevention.
In response to extensive evidence of the serious contamination associated with unrestricted management of waste, governments have established standards for acceptable practices for collection, handling and disposal to ensure environmental protection. Particular attention has been paid to the criteria for environmentally safe disposal through sanitary landfills, incineration and hazardous-waste treatment.
To avoid the potential environmental burden and costs associated with the disposal of waste and promote a more thorough stewardship of scarce resources, waste minimization and recycling have received growing attention. Niels Hahn and Poul Lauridsen provide a summary of the issues that are addressed in pursuing recycling as a preferred waste management strategy, and consider the potential worker exposure implications of this. End-of-pipe abatement risks transferring pollution from one medium to another, where it may either cause equally serious environmental problems, or even end up as an indirect source of pollution to the same medium.
While not as expensive as remediation, end-of-pipe abatement can contribute significantly to the costs of production processes without contributing any value. It also typically is associated with regulatory regimes which add other sets of costs associated with enforcing compliance. While the pollution control approach has achieved considerable success in producing short-term improvements for local pollution problems, it has been less effective in addressing cumulative problems that are increasingly recognized on regional e.
The aim of a health-oriented environmental pollution control programme is to promote a better quality of life by reducing pollution to the lowest level possible.
Environmental pollution control programmes and policies, whose implications and priorities vary from country to country, cover all aspects of pollution air, water, land and so on and involve coordination among areas such as industrial development, city planning, water resources development and transportation policies. Thomas Tseng, Victor Shantora and Ian Smith provide a case study example of the multimedia impact that pollution has had on a vulnerable ecosystem subjected to many stresses - the North American Great Lakes.
The limited effectiveness of the pollution control model in dealing with persistent toxins that dissipate through the environment is particularly examined. By focusing on the approach being pursued in one country and the implications that this has for international action, the implications for actions that address prevention as well as control are illustrated. As environmental pollution control technologies have become more sophisticated and more expensive, there has been a growing interest in ways to incorporate prevention in the design of industrial processes - with the objective of eliminating harmful environmental effects while promoting the competitiveness of industries.
Among the benefits of pollution prevention approaches, clean technologies and toxic use reduction is the potential for eliminating worker exposure to health risks. David Bennett provides an overview of why pollution prevention is emerging as a preferred strategy and how it relates to other environmental management methods.
This approach is central to implementing the shift to sustainable development which has been widely endorsed since the release of the United Nations Commission on Trade and Development in and reiterated at the Rio United Nations Conference on Environment and Development UNCED Conference in He identifies principles that can be usefully applied in assessing opportunities for pursuing this approach.
Dietrich Schwela and Berenice Goelzer. Air pollution management aims at the elimination, or reduction to acceptable levels, of airborne gaseous pollutants, suspended particulate matter and physical and, to a certain extent, biological agents whose presence in the atmosphere can cause adverse effects on human health e. The serious hazards associated with radioactive pollutants, as well as the special procedures required for their control and disposal, also deserve careful attention.
The importance of efficient management of outdoor and indoor air pollution cannot be overemphasized. Unless there is adequate control, the multiplication of pollution sources in the modern world may lead to irreparable damage to the environment and mankind. The objective of this article is to give a general overview of the possible approaches to the management of ambient air pollution from motor vehicle and industrial sources.
However, it is to be emphasized from the very beginning that indoor air pollution in particular, in developing countries might play an even larger role than outdoor air pollution due to the observation that indoor air pollutant concentrations are often substantially higher than outdoor concentrations. Beyond considerations of emissions from fixed or mobile sources, air pollution management involves consideration of additional factors such as topography and meteorology, and community and government participation, among many others all of which must be integrated into a comprehensive programme.
For example, meteorological conditions can greatly affect the ground-level concentrations resulting from the same pollutant emission. Air pollution sources may be scattered over a community or a region and their effects may be felt by, or their control may involve, more than one administration.
Furthermore, air pollution does not respect any boundaries, and emissions from one region may induce effects in another region by long-distance transport. Air pollution management, therefore, requires a multidisciplinary approach as well as a joint effort by private and governmental entities. The sources of man-made air pollution or emission sources are of basically two types:. In addition, there are also natural sources of pollution e.
Natural sources are not discussed in this article. Air pollutants are usually classified into suspended particulate matter dusts, fumes, mists, smokes , gaseous pollutants gases and vapours and odours.
Some examples of usual pollutants are presented below:. Suspended particulate pollutants, besides their effects of provoking respiratory diseases, cancers, corrosion, destruction of plant life and so on, can also constitute a nuisance e.
Gaseous pollutants include sulphur compounds e. Secondary pollutants may be formed by thermal, chemical or photochemical reactions. For example, by thermal action sulphur dioxide can oxidize to sulphur trioxide which, dissolved in water, gives rise to the formation of sulphuric acid mist catalysed by manganese and iron oxides. Photochemical reactions between nitrogen oxides and reactive hydrocarbons can produce ozone O 3 , formaldehyde and peroxyacetyl nitrate PAN ; reactions between HCl and formaldehyde can form bis-chloromethyl ether.
While some odours are known to be caused by specific chemical agents such as hydrogen sulphide H 2 S , carbon disulphide CS 2 and mercaptans R-SH or R1-S-R2 others are difficult to define chemically. Examples of the main pollutants associated with some industrial air pollution sources are presented in table Air quality management aims at the preservation of environmental quality by prescribing the tolerated degree of pollution, leaving it to the local authorities and polluters to devise and implement actions to ensure that this degree of pollution will not be exceeded.
An example of legislation within this approach is the adoption of ambient air quality standards based, very often, on air quality guidelines WHO for different pollutants; these are accepted maximum levels of pollutants or indicators in the target area e. Air quality standards are short-, medium- or long-term values valid for 24 hours per day, 7 days per week, and for monthly, seasonal or annual exposure of all living subjects including sensitive subgroups such as children, the elderly and the sick as well as non-living objects; this is in contrast to maximum permissible levels for occupational exposure, which are for a partial weekly exposure e.
Typical measures in air quality management are control measures at the source, for example, enforcement of the use of catalytic converters in vehicles or of emission standards in incinerators, land-use planning and shut-down of factories or reduction of traffic during unfavourable weather conditions.
The best air quality management stresses that the air pollutant emissions should be kept to a minimum; this is basically defined through emission standards for single sources of air pollution and could be achieved for industrial sources, for example, through closed systems and high-efficiency collectors.
An emission standard is a limit on the amount or concentration of a pollutant emitted from a source. This type of legislation requires a decision, for each industry, on the best means of controlling its emissions i. The emissions inventory is a most complete listing of sources in a given area and of their individual emissions, estimated as accurately as possible from all emitting point, line and area diffuse sources.
When these emissions are compared with emission standards set for a particular source, first hints on possible control measures are given if emission standards are not complied with. The emissions inventory also allows an estimate of air pollutant concentrations for those pollutants for which ambient concentration measurements are difficult or too expensive to perform. The air pollutant concentrations inventory summarizes the results of the monitoring of ambient air pollutants in terms of annual means, percentiles and trends of these quantities.
Compounds measured for such an inventory include the following:. Comparison of air pollutant concentrations with air quality standards or guidelines, if they exist, indicates problem areas for which a causal analysis has to be performed in order to find out which sources are responsible for the non-compliance. Using appropriate meteorology parameters in a suitable dispersion model, annual averages and percentiles can be estimated and compared to air quality standards or guidelines, if they exist.
If the compound or compounds have been fixed in a causal analysis compound-causal analysis , a second analysis has to be performed to find out the responsible sources source-causal analysis. Control measures for industrial facilities include adequate, well-designed, well-installed, efficiently operated and maintained air cleaning devices, also called separators or collectors. Wet collectors scrubbers can be used to collect, at the same time, gaseous pollutants and particulate matter.
Also, certain types of combustion devices can burn combustible gases and vapours as well as certain combustible aerosols. Depending on the type of effluent, one or a combination of more than one collector can be used. The control of odours that are chemically identifiable relies on the control of the chemical agent s from which they emanate e. However, when an odour is not defined chemically or the producing agent is found at extremely low levels, other techniques may be used, such as masking by a stronger, more agreeable and harmless agent or counteraction by an additive which counteracts or partially neutralizes the offensive odour.
It should be kept in mind that adequate operation and maintenance are indispensable to ensure the expected efficiency from a collector. This should be ensured at the planning stage, both from the know-how and financial points of view. Energy requirements must not be overlooked. Whenever selecting an air cleaning device, not only the initial cost but also operational and maintenance costs should be considered.
Whenever dealing with high-toxicity pollutants, high efficiency should be ensured, as well as special procedures for maintenance and disposal of waste materials. Substitution of materials. Examples: substitution of less toxic solvents for highly toxic ones used in certain industrial processes; use of fuels with lower sulphur content e.
You hear about pollution all the time. It could be the smog in your city or the trash covering your beach. There are lots of them. In simple terms, pollution is the introduction of harmful chemicals into some areas of the environment. This could be the toxic gases released from the burning of fossil fuels , or it could be the ash created by a natural volcano eruption. As you can see, pollution can have natural causes or be caused by humans. When you think of environmental pollution, it typically comes in seven different types.
Polluted water has inadequate oxygen levels. There are some useful controls for Soil Pollution. Soil.
You were introduced to wastes and pollutants in Study Session 1, where we discussed the interactions between humans and our environment. Pollution was defined as the introduction into the environment of substances liable to cause harm to humans and other living organisms. Many human activities pollute our environment, adversely affecting the water we drink, the air we breathe, and the soil in which we grow food. In this and the next study session we will look more closely at pollution. In this session you will learn about the different types and sources of pollution and the various human activities that can cause pollution. We will also describe the ways pollution can affect different sectors of the environment: water, air and soil.
Pollution , we probably hear of this term every other day at school, college, and offices. We also come across the term in newspapers, online journals, and media in general. So what is it and why is it deemed harmful? Pollution occurs when pollutants contaminate the natural surroundings; bringing about changes that affect our normal lifestyles adversely.
Theory of Environmental Pollution is one among them. In this article, we have thoroughly discussed the types, causes and impacts of different pollutions affecting humankind. Kidney problems, irritation in eyes, nose and throat, asthma, hypertension and carcinogenic effects on lungs. The improvement of nutrients in water bodies causes eutrophication.
Water pollution is the contamination of water bodies , usually as a result of human activities. Water bodies include for example lakes , rivers , oceans , aquifers and groundwater. Water pollution results when contaminants are introduced into the natural environment.
Он боялся ее как огня. Ее мозги работали словно на совсем другом уровне. Она подавляла его своей красотой, и всякий раз, когда он оказывался рядом, язык у него заплетался. Сейчас она держалась подчеркнуто сдержанно, и это пугало его еще сильнее. - Так в чем же проблема, Фил? - спросил Стратмор, открывая холодильник.
Через несколько секунд двенадцатитонная стальная махина начала поворачиваться. Она попыталась собраться с мыслями, но они упрямо возвращали ее к. Дэвид Беккер.
Он не сомневался в своей победе, не зная, что опоздал. Я всегда добиваюсь своей цели, - подумал Стратмор. Не обращая внимания на пролом в стене, он подошел к электронной двери.
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