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171-471: Since its inception in the early 1990s, more and more devices are recycled worldwide due to increased awareness and investment. Electronic recycling occurs primarily in order to recover valuable rare-earth metals and precious metals , which are in short supply, as well as plastics and metals. These are resold or used in new devices after purification, in effect creating a circular economy . Such processes involve specialised facilities and premises, but within

342-549: A fissile material . The principal sources of rare-earth elements are the minerals bastnäsite ( RCO 3 F , where R is a mixture of rare-earth elements), monazite ( XPO 4 , where X is a mixture of rare-earth elements and sometimes thorium), and loparite ( (Ce,Na,Ca)(Ti,Nb)O 3 ), and the lateritic ion-adsorption clays . Despite their high relative abundance, rare-earth minerals are more difficult to mine and extract than equivalent sources of transition metals (due in part to their similar chemical properties), making

513-595: A CO 2 -rich primary magma, by fractional crystallization of an alkaline primary magma, or by separation of a CO 2 -rich immiscible liquid from. These liquids are most commonly forming in association with very deep Precambrian cratons , like the ones found in Africa and the Canadian Shield. Ferrocarbonatites are the most common type of carbonatite to be enriched in REE, and are often emplaced as late-stage, brecciated pipes at

684-490: A compilation of air pollutant emission factors for a wide range of industrial sources. The United Kingdom, Australia, Canada, and many other countries have published similar compilations, as well as the European Environment Agency . An air pollutant is a material in the air that can have many effects on humans and the ecosystem. The substance can be solid particles, liquid droplets, or gases, and often takes

855-447: A complicated, self-managed, competitive environment where paid listings might not sell. Online classified ads can be similarly risky due to forgery scams and uncertainty. When researching computer companies before a computer purchase, consumers can find out if they offer recycling services. Most major computer manufacturers offer some form of recycling. At the user's request they may mail in their old computers, or arrange for pickup from

1026-532: A component of magnets in hybrid car motors." The global demand for rare-earth elements (REEs) is expected to increase more than fivefold by 2030. The REE geochemical classification is usually done on the basis of their atomic weight . One of the most common classifications divides REE into 3 groups: light rare earths (LREE - from 57 La to 60 Nd), intermediate (MREE - from 62 Sm to 67 Ho) and heavy (HREE - from 68 Er to 71 Lu). REE usually appear as trivalent ions, except for Ce and Eu which can take

1197-612: A continued debate between export-friendly e-cycling and increased regulation of that practice. In the European Union, debate regarding the export of e-waste has resulted in a significant amendment to the WEEE directive (January 2012) with a view to significantly diminishing the export of WEEE (untreated e-waste). During debate in Strasburg, MEPs stated that "53 million tonnes of WEEE were generated in 2009 but only 18% collected for recycling" with

1368-482: A convenient recycler or refurbisher. In the recycling process, TVs, monitors, mobile phones and computers are typically tested for reuse and repaired. If broken, they may be disassembled for parts still having high value if labour is cheap enough. Other e-waste is shredded to roughly 100 mm pieces and manually checked to separate out toxic batteries and capacitors which contain poisonous metals. The remaining pieces are further shredded to ~10 mm and passed under

1539-672: A cord, light or takes some kind of battery. Investment in e-cycling facilities has been increasing recently due to technology's rapid rate of obsolescence, concern over improper methods, and opportunities for manufacturers to influence the secondary market (used and reused products). Higher metal prices can result in more recycling taking place. The controversy around methods stems from a lack of agreement over preferred outcomes. World markets with lower disposable incomes, consider 75% repair and reuse to be valuable enough to justify 25% disposal. Debate and certification standards may be leading to better definitions, though civil law contracts, governing

1710-481: A decent number of physical machines to compensate for hardware failures while maintaining the required reliability and availability. This implies a direct need for a matching underling infrastructure to house all the computers and servers. Scaling this paradigm is also quite limited due to the increasing importance of factors like power efficiency and maintenance efforts, making this kind of computing perfect for mid-sized applications. Although consumer electronics such as

1881-768: A faster rate of breathing than a child engaged in sedentary activity. The daily exposure must therefore include the amount of time spent in each micro-environmental setting as well as the kind of activities performed there. The air pollutant concentration in each microactivity/microenvironmental setting is summed to indicate the exposure. For some pollutants such as black carbon , traffic related exposures may dominate total exposure despite short exposure times since high concentrations coincide with proximity to major roads or participation in (motorized) traffic. A large portion of total daily exposure occurs as short peaks of high concentrations, but it remains unclear how to define peaks and determine their frequency and health impact. In 2021,

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2052-551: A few high-value items that were cherished for years and repaired when necessary, to short-lived items that were rapidly replaced owing to wear or simply fashion, and discarded rather than repaired. This was particularly evident in computing, highlighted by Moore's Law . In 1988 two severe incidents highlighted the approaching e-waste crisis. The cargo barge Khian Sea , was loaded with more than 14,000 tons of toxic ash from Pennsylvania which had been refused acceptance in New Jersey and

2223-657: A few percent of yttrium). Uranium ores from Ontario have occasionally yielded yttrium as a byproduct. Well-known minerals containing cerium, and other LREE, include bastnäsite , monazite , allanite , loparite , ancylite , parisite , lanthanite , chevkinite, cerite , stillwellite , britholite, fluocerite , and cerianite. Monazite (marine sands from Brazil , India , or Australia ; rock from South Africa ), bastnäsite (from Mountain Pass rare earth mine , or several localities in China), and loparite ( Kola Peninsula , Russia ) have been

2394-562: A fifth of the 10-ton e-waste that the city generates each year. According to a report by UNEP titled, "Recycling – from E-Waste to Resources," the amount of e-waste being produced – including mobile phones and computers – could rise by as much as 500 percent over the next decade in some countries, such as India. One theory is that increased regulation of electronic waste and concern over the environmental harm in mature economies creates an economic disincentive to remove residues prior to export. Critics of trade in used electronics maintain that it

2565-657: A health environment is not maintained. Even at levels lower than those considered safe by United States regulators, exposure to three components of air pollution, fine particulate matter, nitrogen dioxide and ozone, correlates with cardiac and respiratory illness. Individual reactions to air pollutants depend on the type of pollutant a person is exposed to, the degree of exposure, and the individual's health status and genetics. The most common sources of air pollution include particulates and ozone (often from burning fossil fuels), nitrogen dioxide, and sulfur dioxide. Children aged less than five years who live in developing countries are

2736-531: A laptop refurbisher in Nevada that claims to be the first to buy laptops online, in 2001. With the constant rising costs due to inflation, many families or schools do not have the sufficient funds available for computers to be used along with education standards. Families also impacted by disaster suffer as well due to the financial impact of the situation they have incurred. Many nonprofit organizations, such as InterConnection.org , can be found locally as well as around

2907-549: A legal definition of air pollution, 31 percent lack outdoor air quality standards, 49 percent restrict their definition to outdoor pollution only, and just 31 percent have laws for tackling pollution originating from outside their borders. National air quality laws have often been highly effective, notably the 1956 Clean Air Act in Britain and the US Clean Air Act , introduced in 1963. Some of these efforts have been successful at

3078-482: A link between air pollution levels and longevity. The WHO estimates that in 2016, ~58% of outdoor air pollution-related premature deaths were due to ischaemic heart disease and stroke. The mechanisms linking air pollution to increased cardiovascular mortality are uncertain, but probably include pulmonary and systemic inflammation. India and China have the highest death rate due to air pollution. India also has more deaths from asthma than any other nation according to

3249-453: A magnet to remove ferrous metals. An eddy current ejects non-ferrous metals, which are sorted by density either by a centrifuge or vibrating plates. Precious metals can be dissolved in acid, sorted, and smelted into ingots. The remaining glass and plastic fractions are separated by density and sold to re-processors. TVs and monitors must be manually disassembled to remove either toxic lead in CRTs or

3420-554: A market for recycling of desktop computers has proven more difficult than exchange programs for laptops, smartphones and other smaller electronics. A basic business model is to provide a seller an instant online quote based on laptop characteristics, then to send a shipping label and prepaid box to the seller, to erase, reformat, and process the laptop, and to pay rapidly by cheque. A majority of these companies are also generalized electronic waste recyclers as well; organizations that recycle computers exclusively include Cash For Laptops ,

3591-544: A maximum number of 25 was estimated. The use of X-ray spectra (obtained by X-ray crystallography ) by Henry Gwyn Jeffreys Moseley made it possible to assign atomic numbers to the elements. Moseley found that the exact number of lanthanides had to be 15, but that element 61 had not yet been discovered. (This is promethium, a radioactive element whose most stable isotope has a half-life of just 18 years.) Using these facts about atomic numbers from X-ray crystallography, Moseley also showed that hafnium (element 72) would not be

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3762-432: A melt phase if one is present. REE are chemically very similar and have always been difficult to separate, but the gradual decrease in ionic radius from light REE (LREE) to heavy REE (HREE), called the lanthanide contraction , can produce a broad separation between light and heavy REE. The larger ionic radii of LREE make them generally more incompatible than HREE in rock-forming minerals, and will partition more strongly into

3933-404: A melt phase, while HREE may prefer to remain in the crystalline residue, particularly if it contains HREE-compatible minerals like garnet . The result is that all magma formed from partial melting will always have greater concentrations of LREE than HREE, and individual minerals may be dominated by either HREE or LREE, depending on which range of ionic radii best fits the crystal lattice. Among

4104-503: A mine in the village of Ytterby in Sweden ; four of the rare-earth elements bear names derived from this single location. A table listing the 17 rare-earth elements, their atomic number and symbol, the etymology of their names, and their main uses (see also Applications of lanthanides ) is provided here. Some of the rare-earth elements are named after the scientists who discovered them, or elucidated their elemental properties, and some after

4275-415: A mixture of natural and human sources. There are also sources from processes other than combustion : Air pollutant emission factors are reported representative values that aim to link the quantity of a pollutant released into the ambient air to an activity connected with that pollutant's release. The weight of the pollutant divided by a unit weight, volume, distance, or time of the activity generating

4446-475: A number of grassroots efforts have contributed to the growth of e-cycling processes which emphasize decreased exports over increased reuse rates. The Electronic Waste Recycling Act was passed in California in 2003. It requires that consumers pay an extra fee for certain types of electronics, and the collected money be then redistributed to recycling companies that are qualified to properly recycle these products. It

4617-485: A practice, and criticism of the specific legislated means proposed to enhance it. A hefty criticism often lobbed at reuse based recyclers is that people think that they are recycling their electronic waste, when in reality it is actually being exported to developing countries like China, India, and Nigeria. For instance, at free recycling drives, "recyclers" may not be staying true to their word, but selling e-waste overseas or to parts brokers. Studies indicate that 50–80% of

4788-414: A quarry in the village of Ytterby , Sweden and termed "rare" because it had never yet been seen. Arrhenius's "ytterbite" reached Johan Gadolin , a Royal Academy of Turku professor, and his analysis yielded an unknown oxide ("earth" in the geological parlance of the day ), which he called yttria . Anders Gustav Ekeberg isolated beryllium from the gadolinite but failed to recognize other elements in

4959-451: A rare-earth element. Moseley was killed in World War I in 1915, years before hafnium was discovered. Hence, the claim of Georges Urbain that he had discovered element 72 was untrue. Hafnium is an element that lies in the periodic table immediately below zirconium , and hafnium and zirconium have very similar chemical and physical properties. During the 1940s, Frank Spedding and others in

5130-404: A separate group of rare-earth elements (the terbium group), or europium was included in the cerium group, and gadolinium and terbium were included in the yttrium group. In the latter case, the f-block elements are split into half: the first half (La–Eu) form the cerium group, and the second half (Gd–Yb) together with group 3 (Sc, Y, Lu) form the yttrium group. The reason for this division arose from

5301-420: A similar effect. In sedimentary rocks, rare-earth elements in clastic sediments are a representation of provenance. The rare-earth element concentrations are not typically affected by sea and river waters, as rare-earth elements are insoluble and thus have very low concentrations in these fluids. As a result, when sediment is transported, rare-earth element concentrations are unaffected by the fluid and instead

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5472-568: A source of toxins and carcinogens . Rapid technology change, low initial cost, and planned obsolescence have resulted in a fast-growing surplus of computers and other electronic components around the globe. Technical solutions are available, but in most cases a legal framework, collection system, logistics, and other services need to be implemented before applying a technical solution. The U.S. Environmental Protection Agency , estimates 30 to 40 million surplus PCs , classified as "hazardous household waste", would be ready for end-of-life management in

5643-426: A spectrum of clinical disorders that include emphysema , bronchiectasis , and chronic bronchitis . COPD risk factors are both genetic and environmental. Elevated particle pollution contributes to the exacerbation of this disease and likely its pathogenesis. The risk of lung disease from air pollution is greatest for infants and young children, whose normal breathing is faster than that of older children and adults;

5814-423: A temperature of 400 °C (752 °F). These elements and their compounds have no biological function other than in several specialized enzymes, such as in lanthanide-dependent methanol dehydrogenases in bacteria. The water-soluble compounds are mildly to moderately toxic, but the insoluble ones are not. All isotopes of promethium are radioactive, and it does not occur naturally in the earth's crust, except for

5985-563: A total of 460,000 deaths in the US were attributed to coal PM 2.5 . The largest cause of air pollution is fossil fuel combustion  – mostly the production and use of cars , electricity production, and heating. There are estimated 4.5 million annual premature deaths worldwide due to pollutants released by high-emission power stations and vehicle exhausts. Diesel exhaust (DE) is a major contributor to combustion-derived particulate matter air pollution. In several human experimental studies, using

6156-515: A trace amount generated by spontaneous fission of uranium-238 . They are often found in minerals with thorium , and less commonly uranium . Though rare-earth elements are technically relatively plentiful in the entire Earth's crust ( cerium being the 25th-most-abundant element at 68 parts per million, more abundant than copper ), in practice this is spread thin across trace impurities, so to obtain rare earths at usable purity requires processing enormous amounts of raw ore at great expense, thus

6327-457: A valence of 3 and form sesquioxides (cerium forms CeO 2 ). Five different crystal structures are known, depending on the element and the temperature. The X-phase and the H-phase are only stable above 2000 K. At lower temperatures, there are the hexagonal A-phase, the monoclinic B-phase, and the cubic C-phase, which is the stable form at room temperature for most of the elements. The C-phase

6498-794: A well-validated exposure chamber setup, DE has been linked to acute vascular dysfunction and increased thrombus formation. A study concluded that PM 2.5 air pollution induced by the contemporary free trade and consumption by the 19 G20 nations causes two million premature deaths annually, suggesting that the average lifetime consumption of about ~28 people in these countries causes at least one premature death (average age ~67) while developing countries "cannot be expected" to implement or be able to implement countermeasures without external support or internationally coordinated efforts. The US EPA has estimated that limiting ground-level ozone concentration to 65 parts per billion (ppb), would avert 1,700 to 5,100 premature deaths nationwide in 2020 compared with

6669-494: A year and fine particulate (PM 2.5 ) pollution around another 2.1 million. The scope of the air pollution crisis is large: In 2018, WHO estimated that "9 out of 10 people breathe air containing high levels of pollutants." Although the health consequences are extensive, the way the problem is handled is considered largely haphazard or neglected. The World Bank has estimated that welfare losses (premature deaths) and productivity losses (lost labour) caused by air pollution cost

6840-510: Is a significant risk factor for a number of pollution-related diseases , including respiratory infections , heart disease , chronic obstructive pulmonary disease (COPD), stroke , and lung cancer . Growing evidence suggests that air pollution exposure may be associated with reduced IQ scores, impaired cognition, increased risk for psychiatric disorders such as depression and detrimental perinatal health. The human health effects of poor air quality are far reaching, but principally affect

7011-685: Is an initiative by the United States Environmental Protection Agency (EPA) which refers to donations, reuse, shredding and general collection of used electronics. Generically, the term refers to the process of collecting, brokering, disassembling, repairing and recycling the components or metals contained in used or discarded electronic equipment, otherwise known as electronic waste (e-waste). "E-cyclable" items include, but are not limited to: televisions, computers, microwave ovens, vacuum cleaners, telephones and cellular phones, stereos, and VCRs and DVDs just about anything that has

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7182-851: Is associated with nearly one in three strokes (29%) worldwide (33.7% of strokes in developing countries versus 10.2% in developed countries). In women, air pollution is not associated with hemorrhagic but with ischemic stroke. Air pollution was found to be associated with increased incidence and mortality from coronary stroke. Associations are believed to be causal and effects may be mediated by vasoconstriction, low-grade inflammation and atherosclerosis . Other mechanisms such as autonomic nervous system imbalance have also been suggested. Research has demonstrated increased risk of developing asthma and chronic obstructive pulmonary disease (COPD) from increased exposure to traffic-related air pollution. Air pollution has been associated with increased hospitalization and mortality from asthma and COPD. COPD comprises

7353-461: Is called the bixbyite structure, as it occurs in a mineral of that name ( (Mn,Fe) 2 O 3 ). As seen in the chart, rare-earth elements are found on Earth at similar concentrations to many common transition metals. The most abundant rare-earth element is cerium , which is actually the 25th most abundant element in Earth's crust , having 68 parts per million (about as common as copper). The exception

7524-654: Is covered by at least two legislations: the Law for the Promotion of Effective Utilization of Resources (LPUR); and, the Law for the Recycling of Specified Kinds of Home Appliances (LRHA). The former, which was passed in 2001, encouraged manufacturers to voluntarily help recycle goods while the LRHA, which was adopted in 2009, required more recycling efforts by both consumers and manufacturers of home appliances. However, no legislation exists to cover

7695-599: Is high, weathering forms a thick argillized regolith, this process is called supergene enrichment and produces laterite deposits; heavy rare-earth elements are incorporated into the residual clay by absorption. This kind of deposit is only mined for REE in Southern China, where the majority of global heavy rare-earth element production occurs. REE-laterites do form elsewhere, including over the carbonatite at Mount Weld in Australia. REE may also be extracted from placer deposits if

7866-420: Is in the lead glass of the cathode ray tube (CRT). A typical 15 inch (38 cm) computer monitor may contain 1.5 pounds (1 kg) of lead but other monitors have been estimated to have up to 8 pounds (4 kg) of lead. Circuit boards contain considerable quantities of lead-tin solders that are more likely to leach into groundwater or create air pollution due to incineration. In US landfills, about 40% of

8037-459: Is introduced with the use of air fresheners , incense , and other scented items. Controlled wood fires in cook stoves and fireplaces can add significant amounts of harmful smoke particulates into the air, inside and out. Indoor pollution fatalities may be caused by using pesticides and other chemical sprays indoors without proper ventilation. Also the kitchen in a modern produce harmful particles and gases, with equipment like toasters being one of

8208-658: Is nitrogen dioxide and other nitrogen oxides (NOx) emitted by road vehicles. Across the European Union , air pollution is estimated to reduce life expectancy by almost nine months. In a 2015 consultation document the UK government disclosed that nitrogen dioxide is responsible for 23,500 premature UK deaths per annum. There is a positive correlation between pneumonia -related deaths and air pollution from motor vehicle emissions in England. Eliminating energy-related fossil fuel emissions in

8379-445: Is possible to observe the serial trend of the REE by reporting their normalized concentrations against the atomic number. The trends that are observed in "spider" diagrams are typically referred to as "patterns", which may be diagnostic of petrological processes that have affected the material of interest. According to the general shape of the patterns or thanks to the presence (or absence) of so-called "anomalies", information regarding

8550-450: Is sent to landfills or incinerated , which releases materials such as lead , mercury , or cadmium into the soil, groundwater , and atmosphere, thus having a negative impact on the environment. Many materials used in computer hardware can be recovered by recycling for use in future production. Reuse of tin , silicon , iron , aluminium , and a variety of plastics that are present in bulk in computers or other electronics can reduce

8721-741: Is stringent legislation designed to enforce and encourage the sustainable disposal of appliances, the most notable being the Waste Electrical and Electronic Equipment Directive of the European Union and the United States National Computer Recycling Act. In 2009, 38% of computers and a quarter of total electronic waste was recycled in the United States, 5% and 3% up from 3 years prior respectively. Obsolete computers and old electronics are valuable sources for secondary raw materials if recycled; otherwise, these devices are

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8892-408: Is strong evidence linking both short- and long-term exposure to air pollution with cardiovascular disease mortality and morbidity, stroke, blood pressure, and ischemic heart diseases (IHD). Air pollution is a leading risk factor for stroke, particularly in developing countries where pollutant levels are highest. A systematic analysis of 17 different risk factors in 188 countries found air pollution

9063-443: Is synthetically produced in nuclear reactors. Due to their chemical similarity, the concentrations of rare earths in rocks are only slowly changed by geochemical processes, making their proportions useful for geochronology and dating fossils. Rare-earth elements occur in nature in combination with phosphate ( monazite ), carbonate - fluoride ( bastnäsite ), and oxygen anions. In their oxides, most rare-earth elements only have

9234-517: Is the highly unstable and radioactive promethium "rare earth" is quite scarce. The longest-lived isotope of promethium has a half-life of 17.7 years, so the element exists in nature in only negligible amounts (approximately 572 g in the entire Earth's crust). Promethium is one of the two elements that do not have stable (non-radioactive) isotopes and are followed by (i.e. with higher atomic number) stable elements (the other being technetium ). The rare-earth elements are often found together. During

9405-491: Is the only state that legislates against e-waste through this kind of consumer fee; the other states' efforts focus on producer responsibility laws or waste disposal bans. No study has shown that per capita recovery is greater in one type of legislated program (e.g. California) versus ordinary waste disposal bans (e.g. Massachusetts), though recovery has greatly increased in states which use either method. Rare-earth element The rare-earth elements ( REE ), also called

9576-461: Is theorized that manufacturers who take part in e-cycling would be motivated to use fewer materials in the production process, create longer lasting products, and implement safer, more efficient recycling systems. This theory is sharply disputed and has never been demonstrated. The critics of e-cycling are just as vocal as its advocates. According to the Reason Foundation , e-cycling only raises

9747-654: Is too easy for brokers calling themselves recyclers to export unscreened electronic waste to developing countries, such as China, India and parts of Africa, thus avoiding the expense of removing items like bad cathode ray tubes (the processing of which is expensive and difficult). The developing countries are becoming big dump yards of e-waste. Proponents of international trade point to the success of fair trade programs in other industries, where cooperation has led creation of sustainable jobs, and can bring affordable technology in countries where repair and reuse rates are higher. Organizations like A2Z Group have stepped in to own up

9918-563: The Oddo–Harkins rule : even-numbered REE at abundances of about 5% each, and odd-numbered REE at abundances of about 1% each. Similar compositions are found in xenotime or gadolinite. Well-known minerals containing yttrium, and other HREE, include gadolinite, xenotime, samarskite , euxenite , fergusonite , yttrotantalite, yttrotungstite, yttrofluorite (a variety of fluorite ), thalenite, and yttrialite . Small amounts occur in zircon , which derives its typical yellow fluorescence from some of

10089-533: The rare-earth metals or rare earths , and sometimes the lanthanides or lanthanoids (although scandium and yttrium , which do not belong to this series, are usually included as rare earths), are a set of 17 nearly indistinguishable lustrous silvery-white soft heavy metals . Compounds containing rare earths have diverse applications in electrical and electronic components, lasers, glass, magnetic materials, and industrial processes. Scandium and yttrium are considered rare-earth elements because they tend to occur in

10260-486: The upper mantle (200 to 600 km depth). This melt becomes enriched in incompatible elements, like the rare-earth elements, by leaching them out of the crystalline residue. The resultant magma rises as a diapir , or diatreme , along pre-existing fractures, and can be emplaced deep in the crust , or erupted at the surface. Typical REE enriched deposits types forming in rift settings are carbonatites, and A- and M-Type granitoids. Near subduction zones, partial melting of

10431-454: The world economy $ 5 trillion per year. The costs of air pollution are generally an externality to the contemporary economic system and most human activity, although they are sometimes recovered through monitoring, legislation, and regulation . Many different technologies and strategies are available for reducing air pollution. Although a majority of countries have air pollution laws , according to UNEP , 43 percent of countries lack

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10602-428: The "heavy" group from 6.965 (ytterbium) to 9.32 (thulium), as well as including yttrium at 4.47. Europium has a density of 5.24. Rare-earth elements, except scandium , are heavier than iron and thus are produced by supernova nucleosynthesis or by the s-process in asymptotic giant branch stars. In nature, spontaneous fission of uranium-238 produces trace amounts of radioactive promethium , but most promethium

10773-600: The 300,000 to 400,000 tons (270,000 to 360,000 tonnes) of e-waste is being sent overseas, and that approximately 2 million tons (1.8 million tonnes) per year go to U.S. landfills. Although not possible in all circumstances, the best way to e-cycle is to upcycle e-waste. On the other hand, the electronic products in question are generally manufactured, and repaired under warranty, in the same nations, which anti-reuse recyclers depict as primitive. Reuse-based e-recyclers believe that fair-trade incentives for export markets will lead to better results than domestic shredding. There has been

10944-568: The 4 f orbital which acts against the electrons of the 6 s and 5 d orbitals. The lanthanide contraction has a direct effect on the geochemistry of the lanthanides, which show a different behaviour depending on the systems and processes in which they are involved. The effect of the lanthanide contraction can be observed in the REE behaviour both in a CHARAC-type geochemical system (CHArge-and-RAdius-Controlled ) where elements with similar charge and radius should show coherent geochemical behaviour, and in non-CHARAC systems, such as aqueous solutions, where

11115-526: The 75 ppb standard. The agency projected the more protective standard would also prevent an additional 26,000 cases of aggravated asthma, and more than a million cases of missed work or school. Following this assessment, the EPA acted to protect public health by lowering the National Ambient Air Quality Standards (NAAQS) for ground-level ozone to 70 ppb. A 2008 economic study of

11286-945: The American Lung Association; the US Consumer Product Safety Commission (CPSC) 2012; and the US Environmental Protection Agency 2012a. Indoor contaminants that can cause pollution include asbestos, biologic agents, building materials, radon, tobacco smoke, and wood stoves, gas ranges, or other heating systems. Radon (Rn) gas, a carcinogen , is exuded from the Earth in certain locations and trapped inside houses. Building materials including carpeting and plywood emit formaldehyde (H-CHO) gas. Paint and solvents give off volatile organic compounds (VOCs) as they dry. Lead paint can degenerate into dust and be inhaled. Intentional air pollution

11457-640: The Caribbean . After sailing for 16 months, all the waste was dumped as "topsoil fertiliser" in Haiti and in the Bay of Bengal by November 1988. In June 1988, a large illegal toxic waste dump which had been created by an Italian company was discovered. This led to the formation of the Basel Convention to stem the flow of poisonous substances from developed countries in 1989. In 1991, the first electronic waste recycling system

11628-499: The House Science and Technology Committee approved funding for research on reducing electronic waste and mitigating environmental impact, regarded by sponsor Ralph Hall ( R - TX ) as the first federal bill to directly address electronic waste. Many states have introduced legislation concerning recycling and reuse of computers or computer parts or other electronics. Most American computer recycling legislations address it from within

11799-498: The LREE. This has economic consequences: large ore bodies of LREE are known around the world and are being exploited. Ore bodies for HREE are more rare, smaller, and less concentrated. Most of the current supply of HREE originates in the "ion-absorption clay" ores of Southern China. Some versions provide concentrates containing about 65% yttrium oxide, with the HREE being present in ratios reflecting

11970-519: The Resource Conservation and Recovery Act. Companies can mitigate these risks by requiring waivers of liability, audit trails, certificates of data destruction, signed confidentiality agreements, and random audits of information security . The National Association of Information Destruction is an international trade association for data destruction providers. Online auctions are an alternative for consumers willing to resell for cash less fees, in

12141-533: The UK, waste or obsolete corporate related computer hardware is treated via third party authorized treatment facilities, who normally impose a charge for its collection and treatment. Since mid 2020 the classification of WEEE changed with regards to POPs ( persistent organic pollutants ). In the UK WEEE containing POPs is now classified as a hazardous waste, this includes printed circuit boards, cable from WEEE and categories 1,2,3,6,7 (cat 4 and 5 unless evidence provided to

12312-614: The USA under the Clean Air Act and in Europe under numerous directives (including the Air "Framework" Directive, 96/62/EC, on ambient air quality assessment and management, Directive 98/24/EC, on risks related to chemical agents at work, and Directive 2004/107/EC covering heavy metals and polycyclic aromatic hydrocarbons in ambient air). The risk of air pollution is determined by the pollutant's hazard and

12483-459: The United States (during the Manhattan Project ) developed chemical ion-exchange procedures for separating and purifying rare-earth elements. This method was first applied to the actinides for separating plutonium-239 and neptunium from uranium , thorium , actinium , and the other actinides in the materials produced in nuclear reactors . Plutonium-239 was very desirable because it is

12654-499: The United States would prevent 46,900–59,400 premature deaths each year and provide $ 537–$ 678 billion in benefits from avoided PM 2.5 -related illness and death. A study published in 2023 in Science focused on sulfur dioxide emissions by coal power plants (coal PM 2.5 ) and concluded that "exposure to coal PM 2.5 was associated with 2.1 times greater mortality risk than exposure to PM 2.5 from all sources." From 1999 to 2020,

12825-480: The WEEE directive via Producer Compliance Schemes (whereby manufacturers of electronics pay into a scheme that funds its recovery from household waste recycling centres (HWRCs) and nominated waste treatment facilities (known as Obligated WEEE). However, recycling of ex-corporate computer hardware and associated electronic equipment falls outside the Producer Compliance Scheme (known as non-obligated). In

12996-460: The WHO halved its recommended guideline limit for tiny particles from burning fossil fuels. The new limit for nitrogen dioxide (NO 2 ) is 75% lower. Growing evidence that air pollution—even when experienced at very low levels—hurts human health, led the WHO to revise its guideline (from 10 μg/m to 5 μg/m ) for what it considers a safe level of exposure of particulate pollution, bringing most of

13167-402: The WHO reported that outdoor air pollution was estimated to cause 4.2 million premature deaths worldwide in 2019. The global mean loss of life expectancy (LLE; similar to YPLL ) from air pollution in 2015 was 2.9 years, substantially more than, for example, 0.3 years from all forms of direct violence. Communities with persons that live beyond 85 years have low ambient air pollution, suggesting

13338-743: The World Health Organization estimated that every year air pollution causes the premature death of 7 million people worldwide, 1 in 8 deaths worldwide. A study published in 2019 indicated that in 2015 the number may be closer to 8.8 million, with 5.5 million of these premature deaths due to air pollution from anthropogenic sources. A 2022 review concluded that in 2019 air pollution was responsible for approximately 9 million premature deaths. It concluded that since 2015 little real progress against pollution has been made. Causes of deaths include strokes, heart disease, COPD , lung cancer, and lung infections. Children are particularly at risk. In 2021,

13509-778: The World Health Organization, these may be defined as asbestosis, lung cancer, and peritoneal mesothelioma (generally a very rare form of cancer, when more widespread it is almost always associated with prolonged exposure to asbestos). Biological sources of air pollution are also found indoors, as gases and airborne particulates. Pets produce dander, people produce dust from minute skin flakes and decomposed hair, dust mites in bedding, carpeting and furniture produce enzymes and micrometre-sized fecal droppings, inhabitants emit methane, mold forms on walls and generates mycotoxins and spores, air conditioning systems can incubate Legionnaires' disease and mold, and houseplants, soil and surrounding gardens can produce pollen , dust, and mold. Indoors,

13680-563: The World Health Organization. In 2019, 1.6 million deaths in India were caused by air pollution. In 2013, air pollution was estimated to kill 500,000 people in China each year. In 2012, 2.48% of China's total air pollution emissions were caused by exports due to US demand, causing an additional 27,963 deaths across 30 provinces. Annual premature European deaths caused by air pollution are estimated at 430,000 to 800,000. An important cause of these deaths

13851-449: The accompanying HREE. The zirconium mineral eudialyte , such as is found in southern Greenland , contains small but potentially useful amounts of yttrium. Of the above yttrium minerals, most played a part in providing research quantities of lanthanides during the discovery days. Xenotime is occasionally recovered as a byproduct of heavy-sand processing, but is not as abundant as the similarly recovered monazite (which typically contains

14022-445: The air when primary pollutants react or interact. Ground level ozone is a prominent example of a secondary pollutant. Some pollutants may be both primary and secondary: they are both emitted directly and formed from other primary pollutants. Pollutants emitted into the atmosphere by human activity include: Secondary pollutants include: There are many other chemicals classed as hazardous air pollutants. Some of these are regulated in

14193-704: The amount of exposure to that pollutant. Air pollution exposure can be measured for a person, a group, such as a neighborhood or a country's children, or an entire population. For example, one would want to determine a geographic area's exposure to a dangerous air pollution, taking into account the various microenvironments and age groups. This can be calculated as an inhalation exposure. This would account for daily exposure in various settings, e.g. different indoor micro-environments and outdoor locations. The exposure needs to include different ages and other demographic groups, especially infants, children, pregnant women, and other sensitive subpopulations. For each specific time that

14364-448: The anhydrous rare-earth phosphates, it is the tetragonal mineral xenotime that incorporates yttrium and the HREE, whereas the monoclinic monazite phase incorporates cerium and the LREE preferentially. The smaller size of the HREE allows greater solid solubility in the rock-forming minerals that make up Earth's mantle, and thus yttrium and the HREE show less enrichment in Earth's crust relative to chondritic abundance than does cerium and

14535-411: The body's respiratory system and the cardiovascular system . Individual reactions to air pollutants depend on the type of pollutant a person is exposed to, the degree of exposure, and the individual's health status and genetics . Air pollution is the largest environmental risk factor for disease and premature death and the fourth largest risk factor overall for human health. Air pollution causes

14706-489: The condition of the underlying infrastructure. This paradigm became more widely used with the introduction of cluster orchestration software like Kubernetes or Apache Mesos , since large monolithic applications require reliability and availability on machine level whereas this kind of software is fault tolerant by design. Those orchestration tools also introduced fairly fast set-up processes allowing to use junkyard computing economically and even making this pattern applicable in

14877-557: The contrary). The United States Congress considers a number of electronic waste bills, like the National Computer Recycling Act introduced by Congressman Mike Thompson (D-CA). The main federal law governing solid waste is the Resource Conservation and Recovery Act of 1976. It covers only CRTs, though state regulations may differ. There are also separate laws concerning battery disposal . On March 25, 2009,

15048-812: The core of igneous complexes; they consist of fine-grained calcite and hematite, sometimes with significant concentrations of ankerite and minor concentrations of siderite. Large carbonatite deposits enriched in rare-earth elements include Mount Weld in Australia, Thor Lake in Canada, Zandkopsdrift in South Africa, and Mountain Pass in the USA. Peralkaline granites (A-Type granitoids) have very high concentrations of alkaline elements and very low concentrations of phosphorus; they are deposited at moderate depths in extensional zones, often as igneous ring complexes, or as pipes, massive bodies, and lenses. These fluids have very low viscosities and high element mobility, which allows for

15219-456: The costs of constructing new systems. Components frequently contain copper , gold , tantalum , silver , platinum , palladium , and lead as well as other valuable materials suitable for reclamation. Computer components contain many toxic substances, like dioxins , polychlorinated biphenyls (PCBs), cadmium , chromium , radioactive isotopes and mercury . A typical computer monitor may contain more than 6% lead by weight, much of which

15390-448: The country exporting and receiving the waste. Companies may find it cost-effective in the short term to sell outdated computers to less developed countries with lax regulations. It is commonly believed that a majority of surplus laptops are routed to developing nations . The high value of working and reusable laptops, computers, and components (e.g. RAM ) can help pay the cost of transportation for many worthless commodities. Laws governing

15561-408: The crude yttria and found the same substances that Mosander obtained, but Berlin named (1860) the substance giving pink salts erbium , and Delafontaine named the substance with the yellow peroxide terbium . This confusion led to several false claims of new elements, such as the mosandrium of J. Lawrence Smith , or the philippium and decipium of Delafontaine. Due to the difficulty in separating

15732-735: The crystallization of large grains, despite a relatively short crystallization time upon emplacement; their large grain size is why these deposits are commonly referred to as pegmatites. Economically viable pegmatites are divided into Lithium-Cesium-Tantalum (LCT) and Niobium-Yttrium-Fluorine (NYF) types; NYF types are enriched in rare-earth minerals. Examples of rare-earth pegmatite deposits include Strange Lake in Canada and Khaladean-Buregtey in Mongolia. Nepheline syenite (M-Type granitoids) deposits are 90% feldspar and feldspathoid minerals. They are deposited in small, circular massifs and contain high concentrations of rare-earth-bearing accessory minerals . For

15903-413: The difference in solubility of rare-earth double sulfates with sodium and potassium. The sodium double sulfates of the cerium group are poorly soluble, those of the terbium group slightly, and those of the yttrium group are very soluble. Sometimes, the yttrium group was further split into the erbium group (dysprosium, holmium, erbium, and thulium) and the ytterbium group (ytterbium and lutetium), but today

16074-409: The electron structure is also an important parameter to consider as the lanthanide contraction affects the ionic potential . A direct consequence is that, during the formation of coordination bonds, the REE behaviour gradually changes along the series. Furthermore, the lanthanide contraction causes the ionic radius of Ho (0.901 Å) to be almost identical to that of Y (0.9 Å), justifying the inclusion of

16245-651: The element showing the anomaly and the predictable one based on the average of the normalized concentrations of the two elements in the previous and next position in the series, according to the equation: where [ REE i ] n {\displaystyle [{\text{REE}}_{i}]_{n}} is the normalized concentration of the element whose anomaly has to be calculated, [ REE i − 1 ] n {\displaystyle [{\text{REE}}_{i-1}]_{n}} and [ REE i + 1 ] n {\displaystyle [{\text{REE}}_{i+1}]_{n}}

16416-525: The environment by avoiding pollution. Such e-cycling can theoretically be a sustainable alternative to disposing of e-waste in landfills. In addition, e-cycling allows for the reclamation of potential conflict minerals , like gold and wolframite , which requires less of those to be mined and lessens the potential money flow to militias and other exploitative actors in third-world that profit from mining them. Supporters of one form of "required e-cycling" legislation argue that e-cycling saves taxpayers money, as

16587-417: The existence of an unknown element. The fractional crystallization of the oxides then yielded europium in 1901. In 1839 the third source for rare earths became available. This is a mineral similar to gadolinite called uranotantalum (now called " samarskite ") an oxide of a mixture of elements such as yttrium, ytterbium, iron, uranium, thorium, calcium, niobium, and tantalum. This mineral from Miass in

16758-403: The expected process are still vital to any contracted process, as poorly defined as "e-cycling". The e-waste disposal occurring after processing for reuse, repair of equipment, and recovery of metals may be unethical or illegal when e-scrap of many kinds is transported overseas to developing countries for such processing. It is transported as if to be repaired and/or recycled, but after processing

16929-426: The exportation of waste electronics are put in place to govern recycling companies in developed countries which ship waste to Third World countries. However, concerns about the impact of e-recycling on human health, the health of recycling workers and environmental degradation remain. For example, due to the lack of strict regulations in developing countries, sometimes workers smash old products, propelling toxins on to

17100-663: The extensive use of asbestos in industrial and domestic environments in the past has left a potentially very dangerous material in many localities. Asbestosis is a chronic inflammatory medical condition affecting the tissue of the lungs. It occurs after long-term, heavy exposure to asbestos from asbestos-containing materials in structures. Those with asbestosis have severe dyspnea (shortness of breath) and are at an increased risk regarding several different types of lung cancer . As clear explanations are not always stressed in non-technical literature, care should be taken to distinguish between several forms of relevant diseases. According to

17271-401: The financial responsibility would be shifted from the taxpayer to the manufacturers. Advocates of more simple legislation (such as landfill bans for e-waste) argue that involving manufacturers does not reduce the cost to consumers, if reuse value is lost, and the resulting costs are then passed on to consumers in new products, particularly affecting markets which can hardly afford new products. It

17442-419: The first place. Further use cases were introduced when continuous delivery was getting more widely accepted. Infrastructure to execute tests and static code analysis was needed which requires as much performance as possible while being extremely cost effective. From an economical and technological perspective, junkyard computing is only practicable for a small number of users or companies. It already requires

17613-511: The following observations apply: anomalies in europium are dominated by the crystallization of feldspars . Hornblende , controls the enrichment of MREE compared to LREE and HREE. Depletion of LREE relative to HREE may be due to the crystallization of olivine , orthopyroxene , and clinopyroxene . On the other hand, the depletion of HREE relative to LREE may be due to the presence of garnet , as garnet preferentially incorporates HREE into its crystal structure. The presence of zircon may also cause

17784-433: The form of Ce and Eu depending on the redox conditions of the system. Consequentially, REE are characterized by a substantial identity in their chemical reactivity, which results in a serial behaviour during geochemical processes rather than being characteristic of a single element of the series. Sc, Y, and Lu can be electronically distinguished from the other rare earths because they do not have f valence electrons, whereas

17955-470: The form of an aerosol (solid particles or liquid droplets dispersed and carried by a gas). A pollutant can be of natural origin or man-made. Pollutants are classified as primary or secondary. Primary pollutants are usually produced by processes such as ash from a volcanic eruption. Other examples include carbon monoxide gas from motor vehicle exhausts or sulfur dioxide released from factories. Secondary pollutants are not emitted directly. Rather, they form in

18126-566: The fractionation of trace elements (including rare-earth elements) into the liquid phase (the melt/magma) into the solid phase (the mineral). If an element preferentially remains in the solid phase it is termed 'compatible', and if it preferentially partitions into the melt phase it is described as 'incompatible'. Each element has a different partition coefficient, and therefore fractionates into solid and liquid phases distinctly. These concepts are also applicable to metamorphic and sedimentary petrology. In igneous rocks, particularly in felsic melts,

18297-405: The geographical locations where discovered. A mnemonic for the names of the sixth-row elements in order is "Lately college parties never produce sexy European girls that drink heavily even though you look". Rare earths were mainly discovered as components of minerals. Ytterbium was found in the "ytterbite" (renamed to gadolinite in 1800) discovered by Lieutenant Carl Axel Arrhenius in 1787 at

18468-463: The ground, contaminating the soil and putting those who do not wear shoes in danger. Other procedures include burning away wire insulation and acid baths to resell circuit boards. These methods pose environmental and health hazards, as toxins are released into the air and acid bath residue can enter the water supply. In Switzerland , the first electronic waste recycling system was implemented in 1991, beginning with collection of old refrigerators; over

18639-508: The health impacts and associated costs of air pollution in the Los Angeles Basin and San Joaquin Valley of Southern California shows that more than 3,800 people die prematurely (approximately 14 years earlier than normal) each year because air pollution levels violate federal standards. The number of annual premature deaths is considerably higher than the fatalities related to auto collisions in

18810-449: The heavy metals of which the electronic products are composed, and as little as 1–5% of the original cost of materials can be retrieved. A final problem that people find is that identity fraud is all too common in regards to the disposal of electronic products. As the programs are legislated, creating winners and losers among e-cyclers with different locations and processes, it may be difficult to distinguish between criticism of e-cycling as

18981-448: The heavy rare-earth elements (HREE), and those that fall in between are typically referred to as the middle rare-earth elements (MREE). Commonly, rare-earth elements with atomic numbers 57 to 61 (lanthanum to promethium) are classified as light and those with atomic numbers 62 and greater are classified as heavy rare-earth elements. Increasing atomic numbers between light and heavy rare-earth elements and decreasing atomic radii throughout

19152-417: The home or ordinary workplace, sound components of damaged or obsolete computers can often be reused, reducing replacement costs. Recycling is considered environmentally friendly because it prevents hazardous waste, including heavy metals and carcinogens, from entering the atmosphere, landfill or waterways. While electronics consist a small fraction of total waste generated, they are far more dangerous. There

19323-630: The international level, such as the Montreal Protocol , which reduced the release of harmful ozone depleting chemicals, and the 1985 Helsinki Protocol , which reduced sulfur emissions , while others, such as international action on climate change , have been less successful. There are many different sources of air pollution. Some air pollutants (such as nitrogen oxides) originate mainly from human activities, while some (notably radon gas) come mostly from natural sources. However, many air pollutants (including dust and sulfur dioxide) come from

19494-1014: The lack of air circulation allows these airborne pollutants to accumulate more than they would otherwise occur in nature. Air pollution has both acute and chronic effects on human health, affecting a number of different systems and organs but principally affect the body's respiratory system and the cardiovascular system. Afflictions include minor to chronic upper respiratory irritation such as difficulty in breathing, wheezing, coughing, asthma and heart disease , lung cancer , stroke , acute respiratory infections in children and chronic bronchitis in adults, aggravating pre-existing heart and lung disease, or asthmatic attacks. Short and long term exposures have been linked with premature mortality and reduced life expectancy and can result in increased medication use, increased doctor or emergency department visits, more hospital admissions and premature death. Diseases that develop from persistent exposure to air pollution are environmental health diseases, which develop when

19665-961: The larger electronic waste issue. In 2001, Arkansas enacted the Arkansas Computer and Electronic Solid Waste Management Act, which requires that state agencies manage and sell surplus computer equipment, establishes a computer and electronics recycling fund, and authorizes the Department of Environmental Quality to regulate and/or ban the disposal of computer and electronic equipment in Arkansas landfills. The recently passed Electronic Device Recycling Research and Development Act distributes grants to universities, government labs and private industries for research in developing projects in line with e-waste recycling and refurbishment. In Japan , sellers and manufacturers of certain electronics (such as televisions and air conditioners ) are required to recycle them. This

19836-470: The latter among the REE. The application of rare-earth elements to geology is important to understanding the petrological processes of igneous , sedimentary and metamorphic rock formation. In geochemistry , rare-earth elements can be used to infer the petrological mechanisms that have affected a rock due to the subtle atomic size differences between the elements, which causes preferential fractionation of some rare earths relative to others depending on

20007-461: The lead content levels are from e-waste. The processing (e.g. incineration and acid treatments) required to reclaim these precious substances may release, generate, or synthesize toxic byproducts. Export of waste to countries with lower environmental standards is a major concern. The Basel Convention includes hazardous wastes such as, but not limited to, CRT screens as an item that may not be exported transcontinentally without prior consent of both

20178-471: The legislation was slow on take-up, with Italy and the United Kingdom being the final member states to pass it into law. The success of the WEEE directive has varied significantly from state to state, with collection rates varying between 13 kilograms per capita per annum to as little as 1 kg per capita per annum. Computers & electronic waste collected from households within Europe are treated under

20349-761: The less valuable e-scrap becomes e-waste/pollution there. Another point of view is that the net environmental cost must be compared to and include the mining, refining and extraction with its waste and pollution cost of new products manufactured to replace secondary products which are routinely destroyed in wealthier nations, and which cannot economically be repaired in older or obsolete products. As an example of negative impacts of e-waste, pollution of groundwater has become so serious in areas surrounding China's landfills that water must be shipped in from 18 miles (29 km) away. However, mining of new metals can have even broader impacts on groundwater. Either thorough e-cycling processing, domestic processing or overseas repair, can help

20520-418: The logarithm to the base 10 of the value. Commonly, the rare-earth elements are normalized to chondritic meteorites , as these are believed to be the closest representation of unfractionated Solar System material. However, other normalizing standards can be applied depending on the purpose of the study. Normalization to a standard reference value, especially of a material believed to be unfractionated, allows

20691-472: The main grouping is between the cerium and the yttrium groups. Today, the rare-earth elements are classified as light or heavy rare-earth elements, rather than in cerium and yttrium groups. The classification of rare-earth elements is inconsistent between authors. The most common distinction between rare-earth elements is made by atomic numbers ; those with low atomic numbers are referred to as light rare-earth elements (LREE), those with high atomic numbers are

20862-573: The manufacturer. Hewlett-Packard also offers free recycling, but only one of its "national" recycling programs is available nationally, rather than in one or two specific states. Hewlett-Packard also offers to pick up any computer product of any brand for a fee, and to offer a coupon against the purchase of future computers or components; it was the largest computer recycler in America in 2003, and it has recycled over 750,000,000 pounds (340,000,000 kg) of electronic waste globally since 1995. It encourages

21033-413: The mercury in flat screens. Corporations face risks both for incompletely destroyed data and for improperly disposed computers. In the UK, some recycling companies use a specialized WEEE-registered contractor to dispose IT equipment and electrical appliances, who disposes it safely and legally. In America, companies are liable for compliance with regulations even if the recycling process is outsourced under

21204-522: The metals (and determining the separation is complete), the total number of false discoveries was dozens, with some putting the total number of discoveries at over a hundred. There were no further discoveries for 30 years, and the element didymium was listed in the periodic table of elements with a molecular mass of 138. In 1879, Delafontaine used the new physical process of optical flame spectroscopy and found several new spectral lines in didymia. Also in 1879, Paul Émile Lecoq de Boisbaudran isolated

21375-688: The most part, these deposits are small but important examples include Illimaussaq-Kvanefeld in Greenland, and Lovozera in Russia. Rare-earth elements can also be enriched in deposits by secondary alteration either by interactions with hydrothermal fluids or meteoric water or by erosion and transport of resistate REE-bearing minerals. Argillization of primary minerals enriches insoluble elements by leaching out silica and other soluble elements, recrystallizing feldspar into clay minerals such kaolinite, halloysite, and montmorillonite. In tropical regions where precipitation

21546-422: The most vulnerable population to death attributable to indoor and outdoor air pollution. Under the Clean Air Act , U.S. EPA sets limits on certain air pollutants, including setting limits on how much can be in the air anywhere in the United States. Mixed exposure to both carbon black and ozone could result in significantly greater health affects. Estimates of deaths toll due to air pollution vary. In 2014

21717-415: The name "rare" earths. Because of their geochemical properties, rare-earth elements are typically dispersed and not often found concentrated in rare-earth minerals . Consequently, economically exploitable ore deposits are sparse. The first rare-earth mineral discovered (1787) was gadolinite , a black mineral composed of cerium, yttrium, iron, silicon, and other elements. This mineral was extracted from

21888-447: The natural environment (for example, climate change , ozone depletion or habitat degradation ) or built environment (for example, acid rain ). Air pollution can be caused by both human activities and natural phenomena. Air quality is closely related to the Earth's climate and ecosystems globally. Many of the contributors of air pollution are also sources of greenhouse emission i.e., burning of fossil fuel . Air pollution

22059-453: The natural features of the atmosphere. There are many different types of air pollutants, such as gases (including ammonia , carbon monoxide , sulfur dioxide , nitrous oxides , methane and chlorofluorocarbons ), particulates (both organic and inorganic) and biological molecules . Air pollution can cause diseases, allergies, and even death to humans; it can also cause harm to other living organisms such as animals and crops, and may damage

22230-560: The new element samarium from the mineral samarskite . The samaria earth was further separated by Lecoq de Boisbaudran in 1886, and a similar result was obtained by Jean Charles Galissard de Marignac by direct isolation from samarskite. They named the element gadolinium after Johan Gadolin , and its oxide was named " gadolinia ". Further spectroscopic analysis between 1886 and 1901 of samaria, yttria, and samarskite by William Crookes , Lecoq de Boisbaudran and Eugène-Anatole Demarçay yielded several new spectral lines that indicated

22401-499: The next few years. The U.S. National Safety Council estimates that 75% of all personal computers ever sold are now surplus electronics. In 2007, the United States Environmental Protection Agency (EPA) stated that more than 63 million computers in the U.S. were traded in for replacements or discarded. Today, 15% of electronic devices and equipment are recycled in the United States. Most electronic waste

22572-450: The non profit and charitable sectors and schools. The term junkyard computing is a colloquial expression for using old or inferior hardware to fulfill computational tasks while handling reliability and availability on software level. It uses abstraction of computational resources via software, allowing hardware replacement at very low effort. Ease of replacement is hereby a corner point since hardware failures are expected at any time due to

22743-424: The normalized concentration, [ REE i ] sam {\displaystyle {[{\text{REE}}_{i}]_{\text{sam}}}} the analytical concentration of the element measured in the sample, and [ REE i ] ref {\displaystyle {[{\text{REE}}_{i}]_{\text{ref}}}} the concentration of the same element in the reference material. It

22914-427: The normalized concentrations of the respectively previous and next elements along the series. The rare-earth elements patterns observed in igneous rocks are primarily a function of the chemistry of the source where the rock came from, as well as the fractionation history the rock has undergone. Fractionation is in turn a function of the partition coefficients of each element. Partition coefficients are responsible for

23085-432: The observed abundances to be compared to the initial abundances of the element. Normalization also removes the pronounced 'zig-zag' pattern caused by the differences in abundance between even and odd atomic numbers . Normalization is carried out by dividing the analytical concentrations of each element of the series by the concentration of the same element in a given standard, according to the equation: where n indicates

23256-516: The ore. After this discovery in 1794, a mineral from Bastnäs near Riddarhyttan , Sweden, which was believed to be an iron – tungsten mineral, was re-examined by Jöns Jacob Berzelius and Wilhelm Hisinger . In 1803 they obtained a white oxide and called it ceria . Martin Heinrich Klaproth independently discovered the same oxide and called it ochroia . It took another 30 years for researchers to determine that other elements were contained in

23427-414: The others do, but the chemical behaviour is almost the same. A distinguishing factor in the geochemical behaviour of the REE is linked to the so-called " lanthanide contraction " which represents a higher-than-expected decrease in the atomic/ionic radius of the elements along the series. This is determined by the variation of the shielding effect towards the nuclear charge due to the progressive filling of

23598-742: The pollutant is how these factors are commonly stated (e.g., kilograms of particulate emitted per tonne of coal burned). These criteria make estimating emissions from diverse sources of pollution easier. Most of the time, these components are just averages of all available data of acceptable quality, and they are thought to be typical of long-term averages. The Stockholm Convention on Persistent Organic Pollutants identified pesticides and other persistent organic pollutants of concern. These include dioxins and furans which are unintentionally created by combustion of organics, like open burning of plastics, and are endocrine disruptors and mutagens . The United States Environmental Protection Agency has published

23769-468: The premature deaths of around 7 million people worldwide each year, or a global mean loss of life expectancy (LLE) of 2.9 years, and there has been no significant change in the number of deaths caused by all forms of pollution since at least 2015. Outdoor air pollution attributable to fossil fuel use alone causes ~3.61 million deaths annually, making it one of the top contributors to human death . Anthropogenic ozone causes around 470,000 premature deaths

23940-446: The principal ores of cerium and the light lanthanides. Enriched deposits of rare-earth elements at the surface of the Earth, carbonatites and pegmatites , are related to alkaline plutonism , an uncommon kind of magmatism that occurs in tectonic settings where there is rifting or that are near subduction zones. In a rift setting, the alkaline magma is produced by very small degrees of partial melting (<1%) of garnet peridotite in

24111-647: The problem to developing countries without enforced environmental legislation. This is cheaper: the cost of recycling of computer monitors in the US is ten times more than in China. Demand in Asia for electronic waste began to grow when scrap yards found they could extract valuable substances such as copper, iron, silicon, nickel and gold, during the recycling process. The Waste Electrical and Electronic Equipment Directive (WEEE Directive) became European Law in February 2003 and covers all aspects of recycling all types of appliance. This

24282-440: The processes at work. The geochemical study of the REE is not carried out on absolute concentrations – as it is usually done with other chemical elements – but on normalized concentrations in order to observe their serial behaviour. In geochemistry, rare-earth elements are typically presented in normalized "spider" diagrams, in which concentration of rare-earth elements are normalized to a reference standard and are then expressed as

24453-433: The product and waste management costs of e-waste for consumers and limits innovation on the part of high-tech companies. They also believe that e-cycling facilities could unintentionally cause great harm to the environment. Critics claim that e-waste doesn't occupy a significant portion of total waste. Another opposition to e-cycling is that many problems are posed in disassembly: the process is costly and dangerous because of

24624-491: The radio have been popular since the 1920s, recycling was almost unheard of until the early 1990s. At the end of the 1970s, the accelerating pace of domestic consumer electronics drastically shortened the lifespan of electronics such as TVs, VCRs and audio. New innovations appeared more quickly, making older equipment considered obsolete. Increased complexity and sophistication of manufacture made local repair more difficult. The retail market shifted gradually, but substantially, from

24795-421: The rare-earth elements relatively expensive. Their industrial use was very limited until efficient separation techniques were developed, such as ion exchange , fractional crystallization, and liquid–liquid extraction during the late 1950s and early 1960s. Some ilmenite concentrates contain small amounts of scandium and other rare-earth elements, which could be analysed by X-ray fluorescence (XRF). Before

24966-567: The recycling of computer or cellphone-related wastes. It is required in South Korea and Taiwan that sellers and manufacturers of electronics be responsible for recycling 75% of their used products. In South Korea, some local governments have introduced recycling initiatives such as the case of Seoul , which launched its specialized e-waste recycling program. This includes the SR Center recycling facility, which takes apart and salvages materials from

25137-466: The remainder being exported or sent to landfill. The Amendment, voted through by a unanimous 95% of representatives, removed the re-use (repair and refurbishmet) aspect of the directive and placed more emphasis upon recycling and recovery of precious metals and base metals. The changes went further by placing the burden upon registered exporters to prove that used equipment leaving Europe was "fit for purpose". Currently, pieces of government legislation and

25308-722: The responsibility to collect and recycle e-waste at various locations in India. Thanks to the National Environmental Management Act 1998 and National Environmental Management Waste Act 2008, any person in any position causing harm to the environment and failing to comply with the Waste Act could be fined R10 Million or put into jail or receive both penalties for their transgressions. Consumer recycling options consists of (see below) sale, donating computers directly to organizations in need, sending devices directly back to their original manufacturers, or getting components to

25479-459: The rock retains the rare-earth element concentration from its source. Air pollution Air pollution is the contamination of air due to the presence of substances called pollutants in the atmosphere that are harmful to the health of humans and other living beings, or cause damage to the climate or to materials. It is also the contamination of the indoor or outdoor environment either by chemical, physical, or biological agents that alters

25650-485: The same ore deposits as the lanthanides and exhibit similar chemical properties, but have different electrical and magnetic properties . The term 'rare-earth' is a misnomer because they are not actually scarce, although historically it took a long time to isolate these elements. These metals tarnish slowly in air at room temperature and react slowly with cold water to form hydroxides, liberating hydrogen. They react with steam to form oxides and ignite spontaneously at

25821-504: The same area, which average fewer than 2,000 per year. A 2021 study found that outdoor air pollution is associated with substantially increased mortality "even at low pollution levels below the current European and North American standards and WHO guideline values" shortly before the WHO adjusted its guidelines. According to the Global Burden of Disease Study , air pollution is responsible for 19% of all cardiovascular deaths. There

25992-576: The seafloor, bit by bit, over tens of millions of years. One square patch of metal-rich mud 2.3 kilometers wide might contain enough rare earths to meet most of the global demand for a year, Japanese geologists report in Nature Geoscience ." "I believe that rare[-]earth resources undersea are much more promising than on-land resources," said Kato. "[C]oncentrations of rare earths were comparable to those found in clays mined in China. Some deposits contained twice as much heavy rare earths such as dysprosium,

26163-487: The sedimentary parent lithology contains REE-bearing, heavy resistate minerals. In 2011, Yasuhiro Kato, a geologist at the University of Tokyo who led a study of Pacific Ocean seabed mud, published results indicating the mud could hold rich concentrations of rare-earth minerals. The deposits, studied at 78 sites, came from "[h]ot plumes from hydrothermal vents pull[ing] these materials out of seawater and deposit[ing] them on

26334-419: The sequential accretion of the Earth, the dense rare-earth elements were incorporated into the deeper portions of the planet. Early differentiation of molten material largely incorporated the rare earths into mantle rocks. The high field strength and large ionic radii of rare earths make them incompatible with the crystal lattices of most rock-forming minerals, so REE will undergo strong partitioning into

26505-497: The series causes chemical variations. Europium is exempt of this classification as it has two valence states: Eu and Eu . Yttrium is grouped as heavy rare-earth element due to chemical similarities. The break between the two groups is sometimes put elsewhere, such as between elements 63 (europium) and 64 (gadolinium). The actual metallic densities of these two groups overlap, with the "light" group having densities from 6.145 (lanthanum) to 7.26 (promethium) or 7.52 (samarium) g/cc, and

26676-479: The shared approach of collection points for consumers and recyclers to meet. Manufacturers often offer a free replacement service when purchasing a new PC. For example, Dell Computers and Apple Inc. may take back old products when one buys a new one. Both refurbish and resell their own computers with a one-year warranty. Many companies purchase and recycle all brands of working and broken laptops and notebook computers from individuals and corporations. Building

26847-401: The southern Ural Mountains was documented by Gustav Rose . The Russian chemist R. Harmann proposed that a new element he called " ilmenium " should be present in this mineral, but later, Christian Wilhelm Blomstrand , Galissard de Marignac, and Heinrich Rose found only tantalum and niobium ( columbium ) in it. The exact number of rare-earth elements that existed was highly unclear, and

27018-766: The subducting plate within the asthenosphere (80 to 200 km depth) produces a volatile-rich magma (high concentrations of CO 2 and water), with high concentrations of alkaline elements, and high element mobility that the rare earths are strongly partitioned into. This melt may also rise along pre-existing fractures, and be emplaced in the crust above the subducting slab or erupted at the surface. REE-enriched deposits forming from these melts are typically S-Type granitoids. Alkaline magmas enriched with rare-earth elements include carbonatites, peralkaline granites (pegmatites), and nepheline syenite . Carbonatites crystallize from CO 2 -rich fluids, which can be produced by partial melting of hydrous-carbonated lherzolite to produce

27189-462: The subgroup is in the setting and engaged in particular activities, the exposure to an air pollutant must integrate the concentrations of the air pollutant with regard to the time spent in each setting and the respective inhalation rates for each subgroup, playing, cooking, reading, working, spending time in traffic, etc. A little child's inhaling rate, for example, will be lower than that of an adult. A young person engaging in strenuous exercise will have

27360-399: The system under examination and the occurring geochemical processes can be obtained. The anomalies represent enrichment (positive anomalies) or depletion (negative anomalies) of specific elements along the series and are graphically recognizable as positive or negative "peaks" along the REE patterns. The anomalies can be numerically quantified as the ratio between the normalized concentration of

27531-479: The time that ion exchange methods and elution were available, the separation of the rare earths was primarily achieved by repeated precipitation or crystallization . In those days, the first separation was into two main groups, the cerium earths (lanthanum, cerium, praseodymium, neodymium, and samarium) and the yttrium earths (scandium, yttrium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium). Europium, gadolinium, and terbium were either considered as

27702-484: The two ores ceria and yttria (the similarity of the rare-earth metals' chemical properties made their separation difficult). In 1839 Carl Gustav Mosander , an assistant of Berzelius, separated ceria by heating the nitrate and dissolving the product in nitric acid . He called the oxide of the soluble salt lanthana . It took him three more years to separate the lanthana further into didymia and pure lanthana. Didymia, although not further separable by Mosander's techniques,

27873-493: The web and give detailed descriptions as to what methods are used for dissemination and detailed instructions on how to donate. The impact can be seen locally and globally, affecting thousands of those in need. In Canada non profit organizations engaged in computer recycling, such as The Electronic Recycling Association Calgary, Edmonton, Vancouver, Winnipeg, Toronto, Montreal, Computers for Schools Canada wide, are very active in collecting and refurbishing computers and laptops to help

28044-445: The work of Advanced Recovery Inc., a small recycler, in trying to safely dismantle computers, even if most waste was landfilled. Several other companies emerged in the early 1990s, chiefly in Europe, where national 'take back' laws compelled retailers to use them. After these schemes were set up, many countries did not have the capacity to deal with the sheer quantity of e-waste they generated or its hazardous nature. They began to export

28215-525: The world—97.3 percent of the global population—into the unsafe zone. A lack of ventilation indoors concentrates air pollution where people often spend the majority of their time. Indoor air pollution can pose a significant health risk. According to EPA reports, the concentrations of many air pollutants can be two to five times higher in indoor air than in outdoor air. Indoor air pollutants can be up to 100 times higher in some cases than they are inside. People can spend up to 90% of their time indoors, according to

28386-535: The worst sources. Carbon monoxide poisoning and fatalities are often caused by faulty vents and chimneys, or by the burning of charcoal indoors or in a confined space, such as a tent. Chronic carbon monoxide poisoning can result even from poorly-adjusted pilot lights . Traps are built into all domestic plumbing to keep sewer gas and hydrogen sulfide , out of interiors. Clothing emits tetrachloroethylene , or other dry cleaning fluids, for days after dry cleaning. Though its use has now been banned in many countries,

28557-471: The years, all other electric and electronic devices were gradually added to the system. The established producer responsibility organization is SWICO, mainly handling information, communication, and organization technology. The European Union implemented a similar system in February 2003, under the Waste Electrical and Electronic Equipment Directive (WEEE Directive, 2002/96/EC). Pan-European adoption of

28728-548: Was followed by Electronic Waste Recycling Act, enshrined in Californian law in January 2005 The 2000s saw a large increase in both the sale of electronic devices and their growth as a waste stream: in 2002 e-waste grew faster than any other type of waste in the EU. This caused investment in modern, automated facilities to cope with the influx of redundant appliances. E-cycling or "E-waste"

28899-516: Was implemented in Switzerland, beginning with collection of old refrigerators but gradually expanding to cover all devices. The organisation SWICO handles the programme, and is a partnership between IT retailers. The first publication to report the recycling of computers and electronic waste was published on the front page of the New York Times on April 14, 1993, by columnist Steve Lohr. It detailed

29070-492: Was in fact still a mixture of oxides. In 1842 Mosander also separated the yttria into three oxides: pure yttria, terbia, and erbia (all the names are derived from the town name "Ytterby"). The earth giving pink salts he called terbium ; the one that yielded yellow peroxide he called erbium . In 1842 the number of known rare-earth elements had reached six: yttrium, cerium, lanthanum, didymium, erbium, and terbium. Nils Johan Berlin and Marc Delafontaine tried also to separate

29241-494: Was once thought to be in space group I 2 1 3 (no. 199), but is now known to be in space group Ia 3 (no. 206). The structure is similar to that of fluorite or cerium dioxide (in which the cations form a face-centred cubic lattice and the anions sit inside the tetrahedra of cations), except that one-quarter of the anions (oxygen) are missing. The unit cell of these sesquioxides corresponds to eight unit cells of fluorite or cerium dioxide, with 32 cations instead of 4. This

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