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103-660: There are several technologies used to treat wastewater for reuse. A combination of these technologies can meet strict treatment standards and make sure that the processed water is hygienically safe, meaning free from pathogens . The following are some of the typical technologies: Ozonation , ultrafiltration , aerobic treatment ( membrane bioreactor ), forward osmosis , reverse osmosis , and advanced oxidation , or activated carbon . Some water-demanding activities do not require high grade water. In this case, wastewater can be reused with little or no treatment. The cost of reclaimed water exceeds that of potable water in many regions of

206-543: A sustainability transition or sustainability transformation . Some barriers arise from nature and its complexity while others are extrinsic to the concept of sustainability. For example, they can result from the dominant institutional frameworks in countries. Global issues of sustainability are difficult to tackle as they need global solutions. Existing global organizations such as the UN and WTO are seen as inefficient in enforcing current global regulations. One reason for this

309-403: A conservation and replanting of timber that there can be a continuous, ongoing and sustainable use". The shift in use of "sustainability" from preservation of forests (for future wood production) to broader preservation of environmental resources (to sustain the world for future generations) traces to a 1972 book by Ernst Basler, based on a series of lectures at M.I.T. The idea itself goes back

412-520: A dual piping system to keep the recycled water separate from the potable water. Usage types are distinguished as follows: Irrigation with recycled municipal wastewater can also serve to fertilize plants if it contains nutrients, such as nitrogen, phosphorus and potassium. There are benefits of using recycled water for irrigation, including the lower cost compared to some other sources and consistency of supply regardless of season, climatic conditions and associated water restrictions. When reclaimed water

515-601: A few days before harvesting to allow pathogens to die off in the sunlight; applying water carefully so it does not contaminate leaves likely to be eaten raw; cleaning vegetables with disinfectant; or allowing fecal sludge used in farming to dry before being used as a human manure. Drawbacks or risks often mentioned include the content of potentially harmful substances such as bacteria, heavy metals, or organic pollutants (including pharmaceuticals, personal care products and pesticides). Irrigation with wastewater can have both positive and negative effects on soil and plants, depending on

618-621: A long time. Large towns on the River Thames upstream of London ( Oxford , Reading , Swindon , Bracknell ) discharge their treated sewage ("non-potable water") into the Thames, which supplies water to London downstream. In the United States, the Mississippi River serves as both the destination of sewage treatment plant effluent and the source of potable water. Non-potable reclaimed water

721-540: A mixture of chemical and biological pollutants. In low-income countries, there are often high levels of pathogens from excreta. In emerging nations , where industrial development is outpacing environmental regulation, there are increasing risks from inorganic and organic chemicals. The World Health Organization developed guidelines for safe use of wastewater in 2006, advocating a ‘multiple-barrier' approach wastewater use, for example by encouraging farmers to adopt various risk-reducing behaviors. These include ceasing irrigation

824-493: A municipal water supply system. Wastewater reclamation can be especially important in relation to human spaceflight . In 1998, NASA announced it had built a human waste reclamation bioreactor designed for use in the International Space Station and a crewed Mars mission. Human urine and feces are input into one end of the reactor and pure oxygen , pure water , and compost ( humanure ) are output from

927-489: A new development path was required, one that sustained human progress not just in a few pieces for a few years, but for the entire planet into the distant future. Thus 'sustainable development' becomes a goal not just for the 'developing' nations, but for industrial ones as well. The Rio Declaration from 1992 is seen as "the foundational instrument in the move towards sustainability". It includes specific references to ecosystem integrity. The plan associated with carrying out

1030-509: A process involving meiosis and fertilization . Meiosis involves the intimate pairing of homologous chromosomes and recombination between them. Examples of eukaryotic pathogens capable of sex include the protozoan parasites Plasmodium falciparum , Toxoplasma gondii , Trypanosoma brucei , Giardia intestinalis , and the fungi Aspergillus fumigatus , Candida albicans and Cryptococcus neoformans . Viruses may also undergo sexual interaction when two or more viral genomes enter

1133-536: A reliable, drought-proof source of drinking water. By using advanced purification processes, they produce water that meets all applicable drinking water standards. System reliability and frequent monitoring and testing are imperative to their meeting stringent controls. The water needs of a community, water sources, public health regulations, costs, and the types of water infrastructure in place— such as distribution systems, man-made reservoirs, or natural groundwater basins— determine if and how reclaimed water can be part of

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1236-426: A single specific definition of sustainability may never be possible. But the concept is still useful. There have been attempts to define it, for example: Some definitions focus on the environmental dimension. The Oxford Dictionary of English defines sustainability as: "the property of being environmentally sustainable; the degree to which a process or enterprise is able to be maintained or continued while avoiding

1339-437: A theorized equilibrium between a pathogen spreading to additional hosts to parasitize resources, while lowering their virulence to keep hosts living for vertical transmission to their offspring. Algae are single-celled eukaryotes that are generally non-pathogenic. Green algae from the genus Prototheca lack chlorophyll and are known to cause the disease protothecosis in humans, dogs, cats, and cattle, typically involving

1442-423: A variety of bacterial, viral, fungal, and parasitic pathogens, cholera is only caused by some strains of Vibrio cholerae . Additionally, some pathogens may only cause disease in hosts with an immunodeficiency . These opportunistic infections often involve hospital-acquired infections among patients already combating another condition. Infectivity involves pathogen transmission through direct contact with

1545-413: A variety of immunodeficiency disorders caused by viruses related to human immunodeficiency virus (HIV), such as BIV and FIV . Humans can be infected with many types of pathogens, including prions, viruses, bacteria, and fungi, causing symptoms like sneezing, coughing, fever, vomiting, and potentially lethal organ failure . While some symptoms are caused by the pathogenic infection, others are caused by

1648-402: A very long time: Communities have always worried about the capacity of their environment to sustain them in the long term. Many ancient cultures, traditional societies , and indigenous peoples have restricted the use of natural resources. The terms sustainability and sustainable development are closely related. In fact, they are often used to mean the same thing. Both terms are linked with

1751-405: A water treatment plant or distribution system. Modern technologies such as reverse osmosis and ultraviolet disinfection are commonly used when reclaimed water will be mixed with the drinking water supply. Many people associate a feeling of disgust with reclaimed water and 13% of a survey group said they would not even sip it. Nonetheless, the main health risk for potable use of reclaimed water

1854-444: A water-saving measure. When used water is eventually discharged back into natural water sources, it can still have benefits to ecosystems , improving streamflow, nourishing plant life and recharging aquifers , as part of the natural water cycle . Global treated wastewater reuse is estimated at 40.7 billion m per year, representing approximately 11% of the total domestic and manufacturing wastewater produced. Municipal wastewater reuse

1957-758: A wide array of pathogens and it has been estimated that only 3% of the disease caused by plant pathogens can be managed. Animals often get infected with many of the same or similar pathogens as humans including prions, viruses, bacteria, and fungi. While wild animals often get illnesses, the larger danger is for livestock animals. It is estimated that in rural settings, 90% or more of livestock deaths can be attributed to pathogens. Animal transmissible spongiform encephalopathy (TSEs) involving prions include bovine spongiform encephalopathy (mad cow disease), chronic wasting disease , scrapie , transmissible mink encephalopathy , feline spongiform encephalopathy , and ungulate spongiform encephalopathy. Other animal diseases include

2060-414: A wide variety of issues such as shorter plant height, growths or pits on tree trunks, root or seed rot, and leaf spots. Common and serious plant fungi include the rice blast fungus , Dutch elm disease , chestnut blight and the black knot and brown rot diseases of cherries, plums, and peaches. It is estimated that pathogenic fungi alone cause up to a 65% reduction in crop yield. Overall, plants have

2163-484: Is a social goal for people to co-exist on Earth over a long period of time. Definitions of this term are disputed and have varied with literature, context, and time. Sustainability usually has three dimensions (or pillars): environmental, economic, and social. Many definitions emphasize the environmental dimension. This can include addressing key environmental problems , including climate change and biodiversity loss . The idea of sustainability can guide decisions at

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2266-436: Is also the implementation of advanced wastewater treatment for the removal of organic micropollutants, which leads to an overall improved water quality. Water recycling and reuse is of increasing importance, not only in arid regions but also in cities and contaminated environments. Already, the groundwater aquifers that are used by over half of the world population are being over-drafted. Reuse will continue to increase as

2369-450: Is bad for the environment. Others focus more on the trade-offs between environmental conservation and achieving welfare goals for basic needs (food, water, health, and shelter). Economic development can indeed reduce hunger or energy poverty . This is especially the case in the least developed countries . That is why Sustainable Development Goal 8 calls for economic growth to drive social progress and well-being. Its first target

2472-510: Is called microbiology , while parasitology refers to the scientific study of parasites and the organisms that host them. There are several pathways through which pathogens can invade a host. The principal pathways have different episodic time frames, but soil has the longest or most persistent potential for harboring a pathogen. Diseases in humans that are caused by infectious agents are known as pathogenic diseases. Not all diseases are caused by pathogens, such as black lung from exposure to

2575-520: Is for: "at least 7 per cent GDP growth per annum in the least developed countries". However, the challenge is to expand economic activities while reducing their environmental impact. In other words, humanity will have to find ways how societal progress (potentially by economic development) can be reached without excess strain on the environment. The Brundtland report says poverty causes environmental problems. Poverty also results from them. So addressing environmental problems requires understanding

2678-445: Is generally treated to only secondary level treatment when used for irrigation. A pump station distributes reclaimed water to users around a city. These may include golf courses, agricultural uses, cooling towers, or landfills. Rather than treating municipal wastewater for reuse purposes, other options can achieve similar effects of freshwater savings: The cost of reclaimed water exceeds that of potable water in many regions of

2781-551: Is increasingly using untreated municipal wastewater for irrigation – often in an unsafe manner. Cities provide lucrative markets for fresh produce, so they are attractive to farmers. However, because agriculture has to compete for increasingly scarce water resources with industry and municipal users, there is often no alternative for farmers but to use water polluted with urban waste directly to water their crops. There can be significant health hazards related to using untreated wastewater in agriculture. Municipal wastewater can contain

2884-412: Is known through scientific study to applications in pursuit of what people want for the future." The 1983 UN Commission on Environment and Development ( Brundtland Commission ) had a big influence on the use of the term sustainability today. The commission's 1987 Brundtland Report provided a definition of sustainable development . The report, Our Common Future , defines it as development that "meets

2987-411: Is not a new phenomenon. But it has been only a local or regional concern for most of human history. Awareness of global environmental issues increased in the 20th century. The harmful effects and global spread of pesticides like DDT came under scrutiny in the 1960s. In the 1970s it emerged that chlorofluorocarbons (CFCs) were depleting the ozone layer . This led to the de facto ban of CFCs with

3090-672: Is often distributed with a dual piping network that keeps reclaimed water pipes completely separate from potable water pipes. There are several technologies used to treat wastewater for reuse. A combination of these technologies can meet strict treatment standards and make sure that the processed water is hygienically safe, meaning free from pathogens . Some common technologies include ozonation , ultrafiltration , aerobic treatment ( membrane bioreactor ), forward osmosis , reverse osmosis , advanced oxidation or activated carbon . Reclaimed water providers use multi-barrier treatment processes and constant monitoring to ensure that reclaimed water

3193-694: Is particularly high in the Middle East and North Africa region , in countries such as the UAE, Qatar, Kuwait and Israel. For the Sustainable Development Goal 6 by the United Nations, Target 6.3 states "Halving the proportion of untreated wastewater and substantially increasing recycling and safe reuse globally by 2030". Treated wastewater can be reused in industry (for example in cooling towers ), in artificial recharge of aquifers, in agriculture, and in

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3296-595: Is particularly high in the Middle East and North Africa region , in countries such as the UAE, Qatar, Kuwait and Israel. The term "water reuse" is generally used interchangeably with terms such as wastewater reuse, water reclamation, and water recycling. A definition by the USEPA states: "Water reuse is the method of recycling treated wastewater for beneficial purposes, such as agricultural and landscape irrigation, industrial processes, toilet flushing, and groundwater replenishing (EPA, 2004)." A similar description is: "Water Reuse,

3399-511: Is publicly acknowledged as an intentional project to recycle water for drinking water. There are two ways in which potable water can be delivered for reuse – "Indirect Potable Reuse" (IPR) and "Direct Potable Reuse". Both these forms of reuse are described below, and commonly involve a more formal public process and public consultation program than is the case with de facto or unacknowledged reuse. Some water agencies reuse highly treated effluent from municipal wastewater or resource recovery plants as

3502-595: Is resistant to the commonly prescribed beta-lactam antibiotics . A 2013 report from the Centers for Disease Control and Prevention (CDC) estimated that in the United States, at least 2 million people get an antibiotic-resistant bacterial infection annually, with at least 23,000 of those patients dying from the infection. Due to their indispensability in combating bacteria, new antibiotics are required for medical care. One target for new antimicrobial medications involves inhibiting DNA methyltransferases , as these proteins control

3605-641: Is safe and treated properly for the intended end use. Some water-demanding activities do not require high grade water. In this case, wastewater can be reused with little or no treatment. One example of this scenario is in the domestic environment where toilets can be flushed using greywater from baths and showers with little or no treatment. In the case of municipal wastewater , the wastewater must pass through numerous sewage treatment process steps before it can be used. Steps might include screening, primary settling, biological treatment, tertiary treatment (for example reverse osmosis), and disinfection. Wastewater

3708-418: Is the lack of suitable sanctioning mechanisms . Governments are not the only sources of action for sustainability. For example, business groups have tried to integrate ecological concerns with economic activity, seeking sustainable business . Religious leaders have stressed the need for caring for nature and environmental stability. Individuals can also live more sustainably . Some people have criticized

3811-574: Is the most common cause of thrush , and Cryptococcus neoformans , which can cause a severe form of meningitis . Typical fungal spores are 4.7 μm long or smaller. Prions are misfolded proteins that transmit their abnormal folding pattern to other copies of the protein without using nucleic acids . Besides obtaining prions from others, these misfolded proteins arise from genetic differences, either due to family history or sporadic mutations. Plants uptake prions from contaminated soil and transport them into their stem and leaves, potentially transmitting

3914-409: Is the potential for pharmaceutical and other household chemicals or their derivatives ( environmental persistent pharmaceutical pollutants ) to persist in this water. This would be less of a concern if human excreta was kept out of sewage by using dry toilets or, alternatively, systems that treat blackwater separately from greywater . Indirect potable reuse (IPR) means the water is delivered to

4017-776: Is used for irrigation in agriculture, the nutrient (nitrogen and phosphorus) content of the treated wastewater has the benefit of acting as a fertilizer . This can make the reuse of excreta contained in sewage attractive. The irrigation water can be used in different ways on different crops, such as for food crops to be eaten raw or for crops which are intended for human consumption to be eaten raw or unprocessed. For processed food crops: crops which are intended for human consumption not to be eaten raw but after food processing (i.e. cooked, industrially processed). It can also be used on crops which are not intended for human consumption (e.g. pastures, forage, fiber, ornamental, seed, forest and turf crops). In developing countries , agriculture

4120-480: Is water that is used more than one time before it passes back into the natural water cycle. Advances in municipal wastewater treatment technology allow communities to reuse water for many different purposes. The water is treated differently depending upon the source and use of the water as well as how it gets delivered. The World Health Organization has recognized the following principal driving forces for municipal wastewater reuse: In some areas, one driving force

4223-632: The Baltimore classification separates viruses by seven classes of mRNA production: Protozoans are single-celled eukaryotes that feed on microorganisms and organic tissues. Many protozoans act as pathogenic parasites to cause diseases like malaria , amoebiasis , giardiasis , toxoplasmosis , cryptosporidiosis , trichomoniasis , Chagas disease , leishmaniasis , African trypanosomiasis (sleeping sickness), Acanthamoeba keratitis , and primary amoebic meningoencephalitis (naegleriasis). Parasitic worms (helminths) are macroparasites that can be seen by

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4326-699: The Montreal Protocol in 1987. In the early 20th century, Arrhenius discussed the effect of greenhouse gases on the climate (see also: history of climate change science ). Climate change due to human activity became an academic and political topic several decades later. This led to the establishment of the IPCC in 1988 and the UNFCCC in 1992. In 1972, the UN Conference on the Human Environment took place. It

4429-439: The anthrax vaccine and pneumococcal vaccine . Many other bacterial pathogens lack vaccines as a preventive measure, but infection by these bacteria can often be treated or prevented with antibiotics . Common antibiotics include amoxicillin , ciprofloxacin , and doxycycline . Each antibiotic has different bacteria that it is effective against and has different mechanisms to kill that bacteria. For example, doxycycline inhibits

4532-405: The echinocandin family of drugs and fluconazole . While algae are commonly not thought of as pathogens, the genus Prototheca causes disease in humans . Treatment for protothecosis is currently under investigation, and there is no consistency in clinical treatment. Many pathogens are capable of sexual interaction. Among pathogenic bacteria , sexual interaction occurs between cells of

4635-531: The natural resources and ecosystem services needed for economies and society. The concept of sustainable development has come to focus on economic development , social development and environmental protection for future generations. Scholars usually distinguish three different areas of sustainability. These are the environmental, the social, and the economic. Several terms are in use for this concept. Authors may speak of three pillars, dimensions, components, aspects, perspectives, factors, or goals. All mean

4738-449: The tobacco mosaic virus which caused scientist Martinus Beijerinck to coin the term "virus" in 1898. Bacterial plant pathogens cause leaf spots, blight, and rot in many plant species. The most common bacterial pathogens for plants are Pseudomonas syringae and Ralstonia solanacearum , which cause leaf browning and other issues in potatoes, tomatoes, and bananas. Fungi are another major pathogen type for plants. They can cause

4841-512: The "integrity of the earth's life-support systems" was essential for sustainability. The authors said that "the SDGs fail to recognize that planetary, people and prosperity concerns are all part of one earth system, and that the protection of planetary integrity should not be a means to an end, but an end in itself". The aspect of environmental protection is not an explicit priority for the SDGs. This causes problems as it could encourage countries to give

4944-441: The "three dimensions of sustainability" concept. One distinction is that sustainability is a general concept, while sustainable development can be a policy or organizing principle. Scholars say sustainability is a broader concept because sustainable development focuses mainly on human well-being. Sustainable development has two linked goals. It aims to meet human development goals. It also aims to enable natural systems to provide

5047-400: The 17 Sustainable Development Goals (SDGs) with their 169 targets as balancing "the three dimensions of sustainable development, the economic, social and environmental". Scholars have discussed how to rank the three dimensions of sustainability. Many publications state that the environmental dimension is the most important. ( Planetary integrity or ecological integrity are other terms for

5150-458: The 1960s and 1970s. This led to discussions on sustainability and sustainable development. This process began in the 1970s with concern for environmental issues. These included natural ecosystems or natural resources and the human environment. It later extended to all systems that support life on Earth, including human society. Reducing these negative impacts on the environment would improve environmental sustainability. Environmental pollution

5253-569: The Brundtland Report, the environment and development are inseparable and go together in the search for sustainability. It described sustainable development as a global concept linking environmental and social issues. It added sustainable development is important for both developing countries and industrialized countries : The 'environment' is where we all live; and 'development' is what we all do in attempting to improve our lot within that abode. The two are inseparable. [...] We came to see that

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5356-651: The Clustered Regularly Interspaced Short Palindromic Repeats ( CRISPR ) associated with bacteriophages, removing the viral genes to avoid infection. This mechanism has been modified for artificial CRISPR gene editing . Plants can play host to a wide range of pathogen types, including viruses, bacteria, fungi, nematodes, and even other plants. Notable plant viruses include the papaya ringspot virus , which has caused millions of dollars of damage to farmers in Hawaii and Southeast Asia, and

5459-492: The Rio Declaration also discusses sustainability in this way. The plan, Agenda 21 , talks about economic, social, and environmental dimensions: Countries could develop systems for monitoring and evaluation of progress towards achieving sustainable development by adopting indicators that measure changes across economic, social and environmental dimensions. Agenda 2030 from 2015 also viewed sustainability in this way. It sees

5562-439: The SDGs. It should also show how to address the trade-offs between ecological footprint and economic development. The social dimension of sustainability is not well defined. One definition states that a society is sustainable in social terms if people do not face structural obstacles in key areas. These key areas are health, influence, competence, impartiality and meaning-making . Some scholars place social issues at

5665-758: The UN launched eight Millennium Development Goals . The aim was for the global community to achieve them by 2015. Goal 7 was to "ensure environmental sustainability". But this goal did not mention the concepts of social or economic sustainability. Specific problems often dominate public discussion of the environmental dimension of sustainability: In the 21st century these problems have included climate change , biodiversity and pollution. Other global problems are loss of ecosystem services , land degradation , environmental impacts of animal agriculture and air and water pollution , including marine plastic pollution and ocean acidification . Many people worry about human impacts on

5768-509: The augmentation of drinking water supplies with municipal wastewater treated to a level suitable for IPR followed by an environmental buffer (e.g. rivers, dams, aquifers, etc.) that precedes drinking water treatment. In this case, municipal wastewater passes through a series of treatment steps that encompasses membrane filtration and separation processes (e.g. MF, UF and RO), followed by an advanced chemical oxidation process (e.g. UV, UV+H 2 O 2 , ozone). In ‘indirect' potable reuse applications,

5871-508: The bodily fluids or airborne droplets of infected hosts, indirect contact involving contaminated areas/items, or transfer by living vectors like mosquitos and ticks . The basic reproduction number of an infection is the expected number of subsequent cases it is likely to cause through transmission. Virulence involves pathogens extracting host nutrients for their survival, evading host immune systems by producing microbial toxins and causing immunosuppression . Optimal virulence describes

5974-477: The composition of the wastewater and on the soil or plant characteristics. The use of reclaimed water to create, enhance, sustain, or augment water bodies including wetlands , aquatic habitats, or stream flow is called "environmental reuse". For example, constructed wetlands fed by wastewater provide both wastewater treatment and habitats for flora and fauna. Treated wastewater can be reused in industry (for example in cooling towers ). Planned potable reuse

6077-753: The consumer indirectly. After it is purified, the reused water blends with other supplies and/or sits a while in some sort of storage, man-made or natural, before it gets delivered to a pipeline that leads to a water treatment plant or distribution system. That storage could be a groundwater basin or a surface water reservoir. Some municipalities are using and others are investigating IPR of reclaimed water. For example, reclaimed water may be pumped into (subsurface recharge) or percolated down to (surface recharge) groundwater aquifers, pumped out, treated again, and finally used as drinking water. This technique may also be referred to as groundwater recharging . This includes slow processes of further multiple purification steps via

6180-432: The drinking water supply. Some communities reuse water to replenish groundwater basins. Others put it into surface water reservoirs. In these instances the reclaimed water is blended with other water supplies and/or sits in storage for a certain amount of time before it is drawn out and gets treated again at a water treatment or distribution system. In some communities, the reused water is put directly into pipelines that go to

6283-478: The economic dimension of sustainability are controversial. Scholars have discussed this under the concept of weak and strong sustainability . For example, there will always be tension between the ideas of "welfare and prosperity for all" and environmental conservation , so trade-offs are necessary. It would be desirable to find ways that separate economic growth from harming the environment . This means using fewer resources per unit of output even while growing

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6386-453: The economy but there is no fixed definition of sustainability indicators . The metrics are evolving and include indicators , benchmarks and audits. They include sustainability standards and certification systems like Fairtrade and Organic . They also involve indices and accounting systems such as corporate sustainability reporting and Triple Bottom Line accounting . It is necessary to address many barriers to sustainability to achieve

6489-399: The economy. This decoupling reduces the environmental impact of economic growth, such as pollution . Doing this is difficult. Some experts say there is no evidence that such a decoupling is happening at the required scale. It is challenging to measure sustainability as the concept is complex, contextual, and dynamic. Indicators have been developed to cover the environment, society, or

6592-584: The environment . These include impacts on the atmosphere, land, and water resources . Human activities now have an impact on Earth's geology and ecosystems . This led Paul Crutzen to call the current geological epoch the Anthropocene . The economic dimension of sustainability is controversial. This is because the term development within sustainable development can be interpreted in different ways. Some may take it to mean only economic development and growth . This can promote an economic system that

6695-528: The environment includes society, and society includes economic conditions. Thus it stresses a hierarchy. Another model shows the three dimensions in a similar way: In this SDG wedding cake model , the economy is a smaller subset of the societal system. And the societal system in turn is a smaller subset of the biosphere system. In 2022 an assessment examined the political impacts of the Sustainable Development Goals. The assessment found that

6798-495: The environment less weight in their developmental plans. The authors state that "sustainability on a planetary scale is only achievable under an overarching Planetary Integrity Goal that recognizes the biophysical limits of the planet". Other frameworks bypass the compartmentalization of sustainability into separate dimensions completely. The environmental dimension is central to the overall concept of sustainability. People became more and more aware of environmental pollution in

6901-426: The environmental dimension.) Protecting ecological integrity is the core of sustainability according to many experts. If this is the case then its environmental dimension sets limits to economic and social development. The diagram with three nested ellipses is one way of showing the three dimensions of sustainability together with a hierarchy: It gives the environmental dimension a special status. In this diagram,

7004-527: The factors behind world poverty and inequality. The report demands a new development path for sustained human progress. It highlights that this is a goal for both developing and industrialized nations. UNEP and UNDP launched the Poverty-Environment Initiative in 2005 which has three goals. These are reducing extreme poverty, greenhouse gas emissions, and net natural asset loss. This guide to structural reform will enable countries to achieve

7107-412: The global, national, organizational, and individual levels. A related concept is that of sustainable development , and the terms are often used to mean the same thing. UNESCO distinguishes the two like this: " Sustainability is often thought of as a long-term goal (i.e. a more sustainable world), while sustainable development refers to the many processes and pathways to achieve it." Details around

7210-768: The highest disease burdens , killing 1.6 million people in 2021, mostly in Africa and Southeast Asia. Bacterial pneumonia is primarily caused by Streptococcus pneumoniae , Staphylococcus aureus , Klebsiella pneumoniae , and Haemophilus influenzae . Foodborne illnesses typically involve Campylobacter , Clostridium perfringens , Escherichia coli , Listeria monocytogenes , and Salmonella . Other infectious diseases caused by pathogenic bacteria include tetanus , typhoid fever , diphtheria , and leprosy . Fungi are eukaryotic organisms that can function as pathogens. There are approximately 300 known fungi that are pathogenic to humans, including Candida albicans , which

7313-505: The host genome, and hijack the host's machinery to produce hundreds of new viruses until the cell bursts open to release them for additional infections. The lytic cycle describes this active state of rapidly killing hosts, while the lysogenic cycle describes potentially hundreds of years of dormancy while integrated in the host genome. Alongside the taxonomy organized by the International Committee on Taxonomy of Viruses (ICTV),

7416-492: The idea of sustainability. One point of criticism is that the concept is vague and only a buzzword . Another is that sustainability might be an impossible goal. Some experts have pointed out that "no country is delivering what its citizens need without transgressing the biophysical planetary boundaries". Sustainability is regarded as a " normative concept ". This means it is based on what people value or find desirable: "The quest for sustainability involves connecting what

7519-458: The immune system of the host, so that when the potential host encounters the virus in the wild, the immune system can defend against infection quickly. Vaccines designed against viruses include annual influenza vaccines and the two-dose MMR vaccine against measles , mumps , and rubella . Vaccines are not available against the viruses responsible for HIV/AIDS , dengue , and chikungunya . Treatment of viral infections often involves treating

7622-420: The immune system's efforts to kill the pathogen, such as feverishly high body temperatures meant to denature pathogenic cells. Despite many attempts, no therapy has been shown to halt the progression of prion diseases . A variety of prevention and treatment options exist for some viral pathogens. Vaccines are one common and effective preventive measure against a variety of viral pathogens. Vaccines prime

7725-561: The intersection of economics, the environment, and the social. There are many broad strategies for more sustainable social systems. They include improved education and the political empowerment of women . This is especially the case in developing countries. They include greater regard for social justice . This involves equity between rich and poor both within and between countries. And it includes intergenerational equity . Providing more social safety nets to vulnerable populations would contribute to social sustainability. A society with

7828-443: The layers of earth/sand (absorption) and microflora in the soil (biodegradation). IPR or even unplanned potable use of reclaimed wastewater is used in many countries, where the latter is discharged into groundwater to hold back saline intrusion in coastal aquifers. IPR has generally included some type of environmental buffer, but conditions in certain areas have created an urgent need for more direct alternatives. IPR occurs through

7931-572: The levels of expression for other genes, such as those encoding virulence factors. Infection by fungal pathogens is treated with anti-fungal medication. Athlete's foot , jock itch , and ringworm are fungal skin infections that are treated with topical anti-fungal medications like clotrimazole . Infections involving the yeast species Candida albicans cause oral thrush and vaginal yeast infections . These internal infections can either be treated with anti-fungal creams or with oral medication. Common anti-fungal drugs for internal infections include

8034-477: The long term. The concept of sustainability, or Nachhaltigkeit in German, goes back to Hans Carl von Carlowitz (1645–1714), and applied to forestry . The term for this now would be sustainable forest management . He used this term to mean the long-term responsible use of a natural resource. In his 1713 work Silvicultura oeconomica, he wrote that "the highest art/science/industriousness [...] will consist in such

8137-474: The long-term depletion of natural resources". The term sustainability is derived from the Latin word sustinere . "To sustain" can mean to maintain, support, uphold, or endure. So sustainability is the ability to continue over a long period of time. In the past, sustainability referred to environmental sustainability. It meant using natural resources so that people in the future could continue to rely on them in

8240-583: The naked eye. Worms live and feed in their living host, acquiring nutrients and shelter in the digestive tract or bloodstream of their host. They also manipulate the host's immune system by secreting immunomodulatory products which allows them to live in their host for years. Helminthiasis is the generalized term for parasitic worm infections, which typically involve roundworms , tapeworms , and flatworms . While bacteria are typically viewed as pathogens, they serve as hosts to bacteriophage viruses (commonly known as phages). The bacteriophage life cycle involves

8343-423: The need to frequently resupply the space station. De facto, unacknowledged or unplanned potable reuse refers to situations where reuse of treated wastewater is practiced but is not officially recognized. For example, a sewage treatment plant from one city may be discharging effluents to a river which is used as a drinking water supply for another city downstream. Unplanned Indirect Potable Use has existed for

8446-442: The needs of the present without compromising the ability of future generations to meet their own needs". The report helped bring sustainability into the mainstream of policy discussions. It also popularized the concept of sustainable development . Some other key concepts to illustrate the meaning of sustainability include: In everyday usage, sustainability often focuses on the environmental dimension. Scholars say that

8549-651: The oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent , or simply a germ . The term pathogen came into use in the 1880s. Typically, the term pathogen is used to describe an infectious microorganism or agent, such as a virus, bacterium, protozoan , prion , viroid , or fungus . Small animals, such as helminths and insects, can also cause or transmit disease. However, these animals are usually referred to as parasites rather than pathogens. The scientific study of microscopic organisms, including microscopic pathogenic organisms,

8652-583: The other end. The soil could be used for growing vegetables , and the bioreactor also produces electricity . Aboard the International Space Station, astronauts have been able to drink recycled urine due to the introduction of the ECLSS system. The system costs $ 250 million and has been working since May 2009. The system recycles wastewater and urine back into potable water used for drinking, food preparation, and oxygen generation. This cuts back on

8755-400: The overall system Reclaimed water systems usually require a dual piping network, often with additional storage tanks , which adds to the costs of the system. Barriers to water reclamation may include: Pathogen This is an accepted version of this page In biology , a pathogen ( Greek : πάθος , pathos "suffering", "passion" and -γενής , -genēs "producer of"), in

8858-453: The pollutant coal dust , genetic disorders like sickle cell disease , and autoimmune diseases like lupus . Pathogenicity is the potential disease-causing capacity of pathogens, involving a combination of infectivity (pathogen's ability to infect hosts) and virulence (severity of host disease). Koch's postulates are used to establish causal relationships between microbial pathogens and diseases. Whereas meningitis can be caused by

8961-822: The prions to herbivorous animals . Additionally, wood, rocks, plastic, glass, cement, stainless steel, and aluminum have been shown binding, retaining, and releasing prions, showcasing that the proteins resist environmental degradation. Prions are best known for causing transmissible spongiform encephalopathy (TSE) diseases like Creutzfeldt–Jakob disease (CJD), variant Creutzfeldt–Jakob disease (vCJD), Gerstmann–Sträussler–Scheinker syndrome (GSS), fatal familial insomnia (FFI), and kuru in humans. While prions are typically viewed as pathogens that cause protein amyloid fibers to accumulate into neurodegenerative plaques, Susan Lindquist led research showing that yeast use prions to pass on evolutionarily beneficial traits. Not to be confused with virusoids or viruses, viroids are

9064-542: The reclaimed wastewater is used directly or mixed with other sources. Direct potable reuse (DPR) means the reused water is put directly into pipelines that go to a water treatment plant or distribution system. Direct potable reuse may occur with or without "engineered storage" such as underground or above ground tanks. In other words, DPR is the introduction of reclaimed water derived from domestic wastewater after extensive treatment and monitoring to assure that strict water quality requirements are met at all times, directly into

9167-495: The rehabilitation of natural ecosystems (for example in wetlands ). The main reclaimed water applications in the world are shown below: In rarer cases reclaimed water is also used to augment drinking water supplies. Most of the uses of water reclamation are non-potable uses such as washing cars, flushing toilets, cooling water for power plants, concrete mixing, artificial lakes, irrigation for golf courses and public parks, and for hydraulic fracturing . Where applicable, systems run

9270-491: The same host cell. This process involves pairing of homologous genomes and recombination between them by a process referred to as multiplicity reactivation. The herpes simplex virus , human immunodeficiency virus , and vaccinia virus undergo this form of sexual interaction. These processes of sexual recombination between homologous genomes supports repairs to genetic damage caused by environmental stressors and host immune systems. Sustainability Sustainability

9373-589: The same species by the process of genetic transformation . Transformation involves the transfer of DNA from a donor cell to a recipient cell and the integration of the donor DNA into the recipient genome through genetic recombination . The bacterial pathogens Helicobacter pylori , Haemophilus influenzae , Legionella pneumophila , Neisseria gonorrhoeae , and Streptococcus pneumoniae frequently undergo transformation to modify their genome for additional traits and evasion of host immune cells. Eukaryotic pathogens are often capable of sexual interaction by

9476-411: The same thing in this context. The three dimensions paradigm has few theoretical foundations. The popular three intersecting circles, or Venn diagram , representing sustainability first appeared in a 1987 article by the economist Edward Barbier . Scholars rarely question the distinction itself. The idea of sustainability with three dimensions is a dominant interpretation in the literature. In

9579-530: The smallest known infectious pathogens. Viroids are small single-stranded, circular RNA that are only known to cause plant diseases, such as the potato spindle tuber viroid that affects various agricultural crops. Viroid RNA is not protected by a protein coat, and it does not encode any proteins, only acting as a ribozyme to catalyze other biochemical reactions. Viruses are generally between 20–200 nm in diameter. For survival and replication, viruses inject their genome into host cells, insert those genes into

9682-688: The soil-associated species Prototheca wickerhami . Bacteria are single-celled prokaryotes that range in size from 0.15 and 700 μM. While the vast majority are either harmless or beneficial to their hosts, such as members of the human gut microbiome that support digestion, a small percentage are pathogenic and cause infectious diseases. Bacterial virulence factors include adherence factors to attach to host cells, invasion factors supporting entry into host cells, capsules to prevent opsonization and phagocytosis , toxins, and siderophores to acquire iron. The bacterial disease tuberculosis , primarily caused by Mycobacterium tuberculosis , has one of

9785-537: The symptoms of the infection, rather than providing medication to combat the viral pathogen itself. Treating the symptoms of a viral infection gives the host immune system time to develop antibodies against the viral pathogen. However, for HIV, highly active antiretroviral therapy (HAART) is conducted to prevent the viral disease from progressing into AIDS as immune cells are lost. Much like viral pathogens, infection by certain bacterial pathogens can be prevented via vaccines. Vaccines against bacterial pathogens include

9888-461: The synthesis of new proteins in both gram-negative and gram-positive bacteria , which makes it a broad-spectrum antibiotic capable of killing most bacterial species. Due to misuse of antibiotics, such as prematurely ended prescriptions exposing bacteria to evolutionary pressure under sublethal doses, some bacterial pathogens have developed antibiotic resistance . For example, a genetically distinct strain of Staphylococcus aureus called MRSA

9991-482: The use of reclaimed water from treated wastewater, has been a long-established reality in many (semi)arid countries and regions. It helps to alleviate water scarcity by supplementing limited freshwater resources." The water that is used as an input to the treatment and reuse processes can be from a variety of sources. Usually it is wastewater ( domestic or municipal, industrial or agricultural wastewater) but it could also come from urban runoff . Reclaimed water

10094-425: The very center of discussions. They suggest that all the domains of sustainability are social. These include ecological , economic, political, and cultural sustainability. These domains all depend on the relationship between the social and the natural. The ecological domain is defined as human embeddedness in the environment. From this perspective, social sustainability encompasses all human activities. It goes beyond

10197-420: The viruses injecting their genome into bacterial cells, inserting those genes into the bacterial genome, and hijacking the bacteria's machinery to produce hundreds of new phages until the cell bursts open to release them for additional infections. Typically, bacteriophages are only capable of infecting a specific species or strain. Streptococcus pyogenes uses a Cas9 nuclease to cleave foreign DNA matching

10300-1010: The world's population becomes increasingly urbanized and concentrated near coastlines, where local freshwater supplies are limited or are available only with large capital expenditure . Large quantities of freshwater can be saved by municipal wastewater reuse and recycling, reducing environmental pollution and improving carbon footprint . Reuse can be an alternative water supply option. Achieving more sustainable sanitation and wastewater management will require emphasis on actions linked to resource management, such as wastewater reuse or excreta reuse that will keep valuable resources available for productive uses. This in turn supports human wellbeing and broader sustainability . Water/wastewater reuse, as an alternative water source, can provide significant economic, social and environmental benefits, which are key motivators for implementing such reuse programs. These benefits include: Reclaiming water for reuse applications instead of using freshwater supplies can be

10403-413: The world, where fresh water is plentiful. However, reclaimed water is usually sold to citizens at a cheaper rate to encourage its use. As fresh water supplies become limited from distribution costs, increased population demands, or climate change , the cost ratios will evolve also. The evaluation of reclaimed water needs to consider the entire water supply system, as it may bring important flexibility into

10506-466: The world, where fresh water is plentiful. The costs of water reclamation options might be compared to the costs of alternative options which also achieve similar effects of freshwater savings, namely greywater reuse systems, rainwater harvesting and stormwater recovery , or seawater desalination . Water recycling and reuse is of increasing importance, not only in arid regions but also in cities and contaminated environments. Municipal wastewater reuse

10609-446: Was the first UN conference on environmental issues. It stated it was important to protect and improve the human environment. It emphasized the need to protect wildlife and natural habitats: The natural resources of the earth, including the air, water, land, flora and fauna and [...] natural ecosystems must be safeguarded for the benefit of present and future generations through careful planning or management, as appropriate. In 2000,

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