The Fédération Internationale de Football Association is an organization which describes itself as an international governing body of association football, fútsal, beach soccer, eFootball. FIFA is responsible for the organization of football's major international tournaments, notably the World Cup which commenced in 1930 and the Women's World Cup which commenced in 1991. FIFA was founded in 1904 to oversee international competition among the national associations of Belgium, France, the Netherlands, Spain and Switzerland. Headquartered in Zürich, its membership now comprises 211 national associations. Member countries must each be members of one of the six regional confederations into which the world is divided: Africa, Europe, North & Central America and the Caribbean and South America. Although FIFA does not control the rules of football, that being the responsibility of the International Football Association Board, it is responsible for both the organization of a number of tournaments and their promotion, which generate revenue from sponsorship.
In 2017, FIFA had revenues of over US $734 million, for a net loss of $189 million, had cash reserves of over US$930 million. Reports by investigative journalists have linked FIFA leadership with corruption and vote-rigging related to the election of FIFA president Sepp Blatter and the organization's decision to award the 2018 and 2022 World Cups to Russia and Qatar, respectively; these allegations led to the indictments of nine high-ranking FIFA officials and five corporate executives by the U. S. Department of Justice on charges including racketeering, wire fraud, money laundering. On 27 May 2015, several of these officials were arrested by Swiss authorities, who were launching a simultaneous but separate criminal investigation into how the organization awarded the 2018 and 2022 World Cups; those among these officials who were indicted in the U. S. are expected to be extradited to face charges there as well. Many officials were suspended by FIFA's ethics committee including Michel Platini. In early 2017 reports became public about FIFA president Gianni Infantino attempting to prevent the re-elections of both chairmen of the ethics committee, Cornel Borbély and Hans-Joachim Eckert, during the FIFA congress in May 2017.
On May 9, 2017, following Infantino's proposal, FIFA Council decided not to renew the mandates of Borbély and Eckert. Together with the chairmen, 11 of 13 committee members were removed; the need for a single body to oversee association football became apparent at the beginning of the 20th century with the increasing popularity of international fixtures. The Fédération Internationale de Football Association was founded in the rear of the headquarters of the Union des Sociétés Françaises de Sports Athlétiques at the Rue Saint Honoré 229 in Paris on 21 May 1904; the French name and acronym are used outside French-speaking countries. The founding members were the national associations of Belgium, France, the Netherlands, Spain and Switzerland; that same day, the German Football Association declared its intention of affiliating through a telegram. The first president of FIFA was Robert Guérin. Guérin was replaced in 1906 by Daniel Burley Woolfall from England, by a member of the association; the first tournament FIFA staged, the association football competition for the 1908 Olympics in London was more successful than its Olympic predecessors, despite the presence of professional footballers, contrary to the founding principles of FIFA.
Membership of FIFA expanded beyond Europe with the application of South Africa in 1909, Argentina in 1912, Canada and Chile in 1913, the United States in 1914. During World War II, with many players sent off to war and the possibility of travel for international fixtures limited, the organization's survival was in doubt. Post-war, following the death of Woolfall, the organisation was run by Dutchman Carl Hirschmann, it was saved from extinction but at the cost of the withdrawal of the Home Nations, who cited an unwillingness to participate in international competitions with their recent World War enemies. The Home Nations resumed their membership; the FIFA collection is held by the National Football Museum at Urbis in England. The first World Cup was held in 1930 in Uruguay. FIFA is headquartered in Zürich, is an association established under the law of Switzerland. FIFA's supreme body is the FIFA Congress, an assembly made up of representatives from each affiliated member association; each national football association has one vote, regardless of footballing strength.
The Congress assembles in ordinary session once every year, extraordinary sessions have been held once a year since 1998. The congress makes decisions relating to FIFA's governing statutes and their method of implementation and application. Only the Congress can pass changes to FIFA's statutes; the congress approves the annual report, decides on the acceptance of new national associations and holds elections. Congress elects the President of FIFA, its general secretary, the other members of the FIFA Council in the year following the FIFA World Cup. FIFA Council — called the FIFA Executive Committee and chaired by the president — is the main decision-making body of the organisation in the intervals of congress; the council is composed of 37 people: the president. The Executive Committee is the body that decides w
The NRG Astrodome known as the Houston Astrodome or the Astrodome, is the world's first multi-purpose, domed sports stadium, located in Houston, Texas. Construction on the stadium began in 1962, it opened in 1965, it served as home to the Houston Astros of Major League Baseball from its opening in 1965 until 1999, the home to the Houston Oilers of the National Football League from 1968 until 1996, the part-time home of the Houston Rockets of the National Basketball Association from 1971 until 1975. Additionally, the Astrodome was the primary venue of the Houston Livestock Show and Rodeo from 1966 until 2002; when opened, it was named the Harris County Domed Stadium and was nicknamed the "Eighth Wonder of the World". After the original natural grass playing surface died, the Astrodome became the first major sports venue to install artificial turf, which became known as AstroTurf. In another technological first, the Astrodome featured the "Astrolite", the first animated scoreboard; the Astrodome was renovated in 1988, altering many original features.
By the 1990s, the Astrodome was becoming obsolete. Unable to secure a new stadium, Oilers owner Bud Adams moved the team to Tennessee after the 1996 season, where they became the Tennessee Titans; the Astros played at the dome through the 1999 season, before relocating to Enron Field in 2000, while the Houston Livestock Show and Rodeo continued to be held at the Astrodome until the opening of the adjacent NRG Stadium in 2002. Although it no longer had any primary tenants, the venue hosted events during the early 2000s, in 2005, was used as a shelter for residents of New Orleans affected by Hurricane Katrina; the Astrodome was declared non-compliant with fire code by the Houston Fire Department in 2008 and parts of it were demolished in 2013 after several years of disuse. In 2014 it was listed on the National Register of Historic Places. Major League Baseball expanded to Houston in 1960; the Houston Colt.45s were to begin play in 1962, along with their expansion brethren New York Mets. Roy Hofheinz, a former mayor of Houston, his group were granted the franchise after they promised to build a covered stadium.
It was thought a covered stadium was a must for a major league team to be viable in Houston due to the area's subtropical climate and hot summers. Game-time temperatures are above 97 °F in July and August, with high humidity and a likelihood of rain. Hofheinz claimed inspiration for what became the Astrodome when he was on a tour of Rome, where he learned that the builders of the ancient Colosseum installed giant velaria to shield spectators from the Roman sun; the Astrodome was conceived by Hofheinz as early as 1952, when he and his daughter Dede were rained out once too at Buffalo Stadium, home of Houston's minor league baseball team, the Houston Buffs. Hofheinz abandoned his interest in the world's first air-conditioned shopping mall, The Galleria, set his sights on bringing major league baseball to Houston; the Astrodome was designed by architects Hermon Lloyd & W. B. Morgan, Wilson, Morris and Anderson. Structural engineering and structural design was performed by Walter P Moore Engineers and Consultants of Houston.
It was constructed by Inc. for Harris County. It stands 18 stories tall; the dome is 710 feet in diameter and the ceiling is 208 feet above the playing surface, which itself sits 25 feet below street level. The scoreboard known as the "Astrolite", was designed by Fair Play Scoreboards of Des Moines, Iowa. Having designed the scoreboard for Dodger Stadium several years prior, team owner Roy Hofheinz was not impressed with the initial proposal for a much more generic type of scoreboard. Project designer Jack Foster teamed up with a creative professional based in Kansas City to create the first animated scoreboard, its reported cost was $2.1 million. The Dome was completed in November 1964, six months ahead of schedule. Many engineering changes were required during construction, including the modest flattening of the supposed "hemispherical roof" to cope with environmentally induced structural deformation and the use of a new paving process called "lime stabilization" to cope with changes in the chemistry of the soil.
The air conditioning system was designed by Houston mechanical engineers Israel A. Naman and Jack Boyd Buckley of I. A. Naman + Associates; the multi-purpose stadium, designed to facilitate both football and baseball, is nearly circular and uses movable lower seating areas. It ushered in the era of other domed stadiums, such as the Mercedes-Benz Superdome in New Orleans, as well as the now-demolished Pontiac Silverdome near Detroit, Hubert H. Humphrey Metrodome in Minneapolis, Kingdome in Seattle, RCA Dome in Indianapolis. To test what effect the enclosed air-conditioned environment might have on the delivery of breaking balls, Satchel Paige, in full Astros uniform, threw the first pitches at the Astrodome on February 7, 1965, he concluded that it was a "pitcher's paradise", as the lack of wind allowed for sensitive pitches to maneuver more easily. Hofheinz had an opulent apartment in the Dome, removed when the facility was remodeled in 1988. On Opening Day, April 9, 1965, a sold-out crowd of 47,879 watched an exhibition game between the Houston Astros and the New York Yankees.
President Lyndon B. Johnson and his wife Lady Bird were in attendance, as well as Texas Governor John Connally and Houston Mayor Louie Welch. Governor Connally tossed out the first ball for the first game played indoors. Dick "Turk" Farrell of
Natural rubber called India rubber or caoutchouc, as produced, consists of polymers of the organic compound isoprene, with minor impurities of other organic compounds, plus water. Thailand and Indonesia are two of the leading rubber producers. Forms of polyisoprene that are used as natural rubbers are classified as elastomers. Rubber is harvested in the form of the latex from the rubber tree or others; the latex is a sticky, milky colloid drawn off by making incisions in the bark and collecting the fluid in vessels in a process called "tapping". The latex is refined into rubber ready for commercial processing. In major areas, latex is allowed to coagulate in the collection cup; the coagulated lumps are processed into dry forms for marketing. Natural rubber is used extensively in many applications and products, either alone or in combination with other materials. In most of its useful forms, it has a large stretch ratio and high resilience, is waterproof; the major commercial source of natural rubber latex is the Pará rubber tree, a member of the spurge family, Euphorbiaceae.
This species is preferred. A properly managed tree responds to wounding by producing more latex for several years. Congo rubber a major source of rubber, came from vines in the genus Landolphia. Dandelion milk contains latex; the latex exhibits the same quality as the natural rubber from rubber trees. In the wild types of dandelion, latex content varies greatly. In Nazi Germany, research projects tried to use dandelions as a base for rubber production, but failed. In 2013, by inhibiting one key enzyme and using modern cultivation methods and optimization techniques, scientists in the Fraunhofer Institute for Molecular Biology and Applied Ecology in Germany developed a cultivar, suitable for commercial production of natural rubber. In collaboration with Continental Tires, IME began a pilot facility. Many other plants produce forms of latex rich in isoprene polymers, though not all produce usable forms of polymer as as the Pará; some of them require more elaborate processing to produce anything like usable rubber, most are more difficult to tap.
Some produce other desirable materials, for example chicle from Manilkara species. Others that have been commercially exploited, or at least showed promise as rubber sources, include the rubber fig, Panama rubber tree, various spurges, the related Scorzonera tau-saghyz, various Taraxacum species, including common dandelion and Russian dandelion, most for its hypoallergenic properties, guayule; the term gum rubber is sometimes applied to the tree-obtained version of natural rubber in order to distinguish it from the synthetic version. The first use of rubber was by the indigenous cultures of Mesoamerica; the earliest archeological evidence of the use of natural latex from the Hevea tree comes from the Olmec culture, in which rubber was first used for making balls for the Mesoamerican ballgame. Rubber was used by the Maya and Aztec cultures – in addition to making balls Aztecs used rubber for other purposes such as making containers and to make textiles waterproof by impregnating them with the latex sap.
The Pará rubber tree is indigenous to South America. Charles Marie de La Condamine is credited with introducing samples of rubber to the Académie Royale des Sciences of France in 1736. In 1751, he presented a paper by François Fresneau to the Académie that described many of rubber's properties; this has been referred to as the first scientific paper on rubber. In England, Joseph Priestley, in 1770, observed that a piece of the material was good for rubbing off pencil marks on paper, hence the name "rubber", it made its way around England. In 1764 François Fresnau discovered. Giovanni Fabbroni is credited with the discovery of naphtha as a rubber solvent in 1779. South America remained the main source of latex rubber used during much of the 19th century; the rubber trade was controlled by business interests but no laws expressly prohibited the export of seeds or plants. In 1876, Henry Wickham smuggled 70,000 Pará rubber tree seeds from Brazil and delivered them to Kew Gardens, England. Only 2,400 of these germinated.
Seedlings were sent to India, British Ceylon, Dutch East Indies and British Malaya. Malaya was to become the biggest producer of rubber. In the early 1900s, the Congo Free State in Africa was a significant source of natural rubber latex gathered by forced labor. King Leopold II's colonial state brutally enforced production quotas. Tactics to enforce the rubber quotas included removing the hands of victims to prove they had been killed. Soldiers came back from raids with baskets full of chopped-off hands. Villages that resisted were razed to encourage better compliance locally. See Atrocities in the Congo Free State for more information on the rubber trade in the Congo Free State in the late 1800s and early 1900s. Liberia and Nigeria started production. In India, commercial cultivation was introduced by British planters, although the experimental efforts to grow rubber on a commercial scale were initiated as early as 1873 at the Calcutta Botanical Gardens; the first commercial Hevea plantations were established at Thattekadu in Kerala in 1902.
In years the plantation expanded to Karnataka, Tamil Nadu and the Andaman and Nicobar Islands of India. India today is the
Copper is a chemical element with symbol Cu and atomic number 29. It is a soft and ductile metal with high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orange color. Copper is used as a conductor of heat and electricity, as a building material, as a constituent of various metal alloys, such as sterling silver used in jewelry, cupronickel used to make marine hardware and coins, constantan used in strain gauges and thermocouples for temperature measurement. Copper is one of the few metals; this led to early human use in several regions, from c. 8000 BC. Thousands of years it was the first metal to be smelted from sulfide ores, c. 5000 BC, the first metal to be cast into a shape in a mold, c. 4000 BC and the first metal to be purposefully alloyed with another metal, tin, to create bronze, c. 3500 BC. In the Roman era, copper was principally mined on Cyprus, the origin of the name of the metal, from aes сyprium corrupted to сuprum, from which the words derived and copper, first used around 1530.
The encountered compounds are copper salts, which impart blue or green colors to such minerals as azurite and turquoise, have been used and as pigments. Copper used in buildings for roofing, oxidizes to form a green verdigris. Copper is sometimes used in decorative art, both in its elemental metal form and in compounds as pigments. Copper compounds are used as bacteriostatic agents and wood preservatives. Copper is essential to all living organisms as a trace dietary mineral because it is a key constituent of the respiratory enzyme complex cytochrome c oxidase. In molluscs and crustaceans, copper is a constituent of the blood pigment hemocyanin, replaced by the iron-complexed hemoglobin in fish and other vertebrates. In humans, copper is found in the liver and bone; the adult body contains between 2.1 mg of copper per kilogram of body weight. Copper and gold are in group 11 of the periodic table; the filled d-shells in these elements contribute little to interatomic interactions, which are dominated by the s-electrons through metallic bonds.
Unlike metals with incomplete d-shells, metallic bonds in copper are lacking a covalent character and are weak. This observation explains the low high ductility of single crystals of copper. At the macroscopic scale, introduction of extended defects to the crystal lattice, such as grain boundaries, hinders flow of the material under applied stress, thereby increasing its hardness. For this reason, copper is supplied in a fine-grained polycrystalline form, which has greater strength than monocrystalline forms; the softness of copper explains its high electrical conductivity and high thermal conductivity, second highest among pure metals at room temperature. This is because the resistivity to electron transport in metals at room temperature originates from scattering of electrons on thermal vibrations of the lattice, which are weak in a soft metal; the maximum permissible current density of copper in open air is 3.1×106 A/m2 of cross-sectional area, above which it begins to heat excessively. Copper is one of a few metallic elements with a natural color other than silver.
Pure copper acquires a reddish tarnish when exposed to air. The characteristic color of copper results from the electronic transitions between the filled 3d and half-empty 4s atomic shells – the energy difference between these shells corresponds to orange light; as with other metals, if copper is put in contact with another metal, galvanic corrosion will occur. Copper does not react with water, but it does react with atmospheric oxygen to form a layer of brown-black copper oxide which, unlike the rust that forms on iron in moist air, protects the underlying metal from further corrosion. A green layer of verdigris can be seen on old copper structures, such as the roofing of many older buildings and the Statue of Liberty. Copper tarnishes when exposed to some sulfur compounds, with which it reacts to form various copper sulfides. There are 29 isotopes of copper. 63Cu and 65Cu are stable, with 63Cu comprising 69% of occurring copper. The other isotopes are radioactive, with the most stable being 67Cu with a half-life of 61.83 hours.
Seven metastable isotopes have been characterized. Isotopes with a mass number above 64 decay by β−, whereas those with a mass number below 64 decay by β+. 64Cu, which has a half-life of 12.7 hours, decays both ways.62Cu and 64Cu have significant applications. 62Cu is used in 62Cu-PTSM as a radioactive tracer for positron emission tomography. Copper is produced in massive stars and is present in the Earth's crust in a proportion of about 50 parts per million. In nature, copper occurs in a variety of minerals, including native copper, copper sulfides such as chalcopyrite, digenite and chalcocite, copper sulfosalts such as tetrahedite-tennantite, enargite, copper carbonates such as azurite and malachite, as copper or copper oxides such as cuprite and tenorite, respectively; the largest mass of elemental copper discovered weighed 420 tonnes and was found in 1857 on the Keweenaw Peninsula in Michigan, US. Native copper is a polycrystal
AstroTurf is an American subsidiary that produces artificial turf for playing surfaces. The original AstroTurf product was a short-pile synthetic turf. Since the early 2000s, AstroTurf has marketed taller pile systems that use infill materials to better replicate natural turf; the prime reason to incorporate AstroTurf on game fields is to avoid the cost of laying and maintaining natural turf and to maximize hours of usage. In 2016, AstroTurf became a subsidiary of German-based SportGroup, a family of sports surfacing companies, which itself is owned by the investment firm Equistone Partners Europe; the original AstroTurf brand product was co-invented in 1965 by Donald L. Elbert, James M. Faria, Robert T. Wright, it was patented in 1965 and sold under the name "ChemGrass". It was rebranded as AstroTurf by a company employee named John A. Wortmann after its first well-publicized use at the Houston Astrodome stadium in 1966. Early iterations of the short-pile turf swept many major stadiums, but the product did need improvement.
Concerns over directionality and traction led Monsanto's R&D department to implement a texturized nylon system. By imparting a crimped texture to the nylon after it was extruded, the product became uniform. In 1987, Monsanto consolidated its AstroTurf management and technical activities in Dalton, Georgia, as AstroTurf Industries, Inc. In 1988, Balsam AG purchased all the capital stock of Inc.. In 1994, Southwest Recreational Industries, Inc. acquired the AstroTurf brand. In 1996, SRI was acquired by American Sports Products Group Inc. While AstroTurf was the industry leader throughout the late 20th century, other companies emerged in the early 2000s. FieldTurf, AstroTurf's chief competitor since the early 2000s, marketed a product of tall-pile polyethylene turf with infill, meant to mimic natural grass more than the older products; this third-generation turf, as it became known, changed the landscape of the marketplace. Although SRI marketed AstroPlay, a third-generation turf product, increased competition gave way to lawsuits.
In 2000, SRI was awarded $1.5 million in a lawsuit after FieldTurf was deemed to have lied to the public by making false statements regarding its own product and making false claims about AstroTurf and AstroPlay products. Despite their legal victory, increased competition took its toll. In 2004, SRI declared bankruptcy. Out of the bankruptcy proceedings, Textile Management Associates, Inc. of Dalton, acquired the AstroTurf brand and other assets. TMA began marketing the AstroTurf brand under the company AstroTurf, LLC. In 2006, General Sports Venue became TMA's marketing partner for the AstroTurf brand for the American market. AstroTurf, LLC handled the marketing of AstroTurf in the rest of the world. In 2009, TMA acquired GSV to enter the marketplace as a direct seller. AstroTurf, LLC focused its efforts on development, which has promoted rapid growth. AstroTurf introduced new product features and installation methods, including AstroFlect and field prefabrication. AstroTurf introduced a product called "RootZone" consisting of crimped fibers designed to encapsulate infill.
This product has been adopted by many professional colleges in the United States. In 2016, SportGroup Holding announced that it would purchase AstroTurf, along with its associated manufacturing facilities; the AstroTurf brand now operates in North America as AstroTurf Corporation. 1964 The Moses Brown School in Providence, Rhode Island, installs ChemGrass.1966 First major installation of AstroTurf at the Houston Astrodome indoor stadium for the Houston Astros. The infield portion was in place before opening day in April. According to script development notes, the installation firm hired by Mike to lay the turf was owned by his college roommate, who had just started a landscaping business after returning from a combat tour in Vietnam with the 18th Engineer Brigade. However, in keeping with studio instructions, no direct mention of the war in Vietnam appeared in the script; the scene in which the installation takes place was cut, so never appeared in the series. 1970 The 1970 World Series is the first with games on AstroTurf, as the Reds play the Baltimore Orioles.1971 The CFL's Hamilton Tiger-Cats install AstroTurf at their home stadium, Ivor Wynne Stadium, in preparation for hosting the Grey Cup game the next year.1972 The Kansas City Chiefs home field of Arrowhead Stadium and the Kansas City Royals home field of Royals Stadium open in Kansas City, with AstroTurf playing surfaces.1973 The Buffalo Bills' home field of Rich Stadium opens in Orchard Park, New York, with an AstroTurf playing surface.1974 The Miami Dolphins face the Minnesota Vikings on AstroTurf in Super Bowl VIII – Rice Stadium, Texas.1975 The first international field hockey game is played on AstroTurf at Molson Stadium, Montreal.
1980 The Philadelphia Phillies and Kansas City Royals play the entire 1980 World Series on AstroTurf in their ballparks.1984 AstroTurf installs the first North American vertical drainage systems in Ewing, New Jersey, at Trenton Sta
Aquatic toxicology is the study of the effects of manufactured chemicals and other anthropogenic and natural materials and activities on aquatic organisms at various levels of organization, from subcellular through individual organisms to communities and ecosystems. Aquatic toxicology is a multidisciplinary field which integrates toxicology, aquatic ecology and aquatic chemistry; this field of study includes marine water and sediment environments. Common tests include standardized acute and chronic toxicity tests lasting 24–96 hours to 7 days or more; these tests measure endpoints such as survival, reproduction, that are measured at each concentration in a gradient, along with a control test. Using selected organisms with ecologically relevant sensitivity to toxicants and a well-established literature background; these organisms can be acquired or cultured in lab and are easy to handle. While basic research in toxicology began in multiple countries in the 1800s, it was not until around the 1930s that the use of acute toxicity testing on fish, was established.
Over the next two decades, the effects of chemicals and wastes on non-human species became more of a public issue and the era of the pickle-jar bioassays began as efforts increased to standardize toxicity testing techniques. In the United States, the passage of the Federal Water Pollution Control Act of 1947 marked the first comprehensive legislation for the control of water pollution and was followed by the Federal Water Pollution Control Act in 1956. In 1962, public and governmental interests were renewed, in large part due to the publication of Rachel Carson’s Silent Spring, three years the Water Quality Act of 1965 was passed, which directed states to develop water quality standards. Public awareness, as well as scientific and governmental concern, continued to grow throughout the 1970s and by the end of the decade research had expanded to include hazard evaluation and risk analysis. In the subsequent decades, aquatic toxicology has continued to expand and internationalize so that there is now a strong application of toxicity testing for environmental protection.
Aquatic toxicology tests: toxicity tests are used to provide qualitative and quantitative data on adverse effects on aquatic organisms from a toxicant. Toxicity tests can be used to assess the potential for damage to an aquatic environment and provide a database that can be used to assess the risk associated within a situation for a specific toxicant. Aquatic toxicology tests can be performed in the laboratory. Field experiments refer to multiple species exposure and laboratory experiments refer to single species exposure. A dose–response relationship is most used with a sigmoidal curve to quantify the toxic effects at a selected end-point or criteria for effect. Concentration is on the x-axis and percent inhibition or response is on the y-axis; the criteria for effects, or endpoints tested for, can include sublethal effects. There are different types of toxicity tests. Different species differ in their susceptibility to chemicals, most due to differences in accessibility, metabolic rate, excretion rate, genetic factors, dieteary factors, sex and stress level of the organism.
Common standard test species are the fathead minnow, midge, rainbow trout, sheepshead minnow, zebra fish, oyster, grass shrimp and mussels. As defined by ASTM, these species are selected on the basis of availability, commercial and ecological importance, past successful use, regulatory use. A variety of acceptable standardized test methods have been published; some of the more accepted agencies to publish methods are: the American Public Health Association, US Environmental Protection Agency, ASTM International, International Organization for Standardization and Climate Change Canada, Organisation for Economic Co-operation and Development. Standardized tests offer the ability to compare results between laboratories. There are many kinds of toxicity tests accepted in the scientific literature and regulatory agencies; the type of test used depends on many factors: Specific regulatory agency conducting the test, resources available and chemical characteristics of the environment, type of toxicant, test species available, laboratory vs. field testing, end-point selection, time and resources available to conduct the assays are some of the most common influencing factors on test design.
Exposure systems are four general techniques the controls and test organisms are exposed to the dealing with treated and diluted water or the test solutions. Static. A static test exposes the organism in still water; the toxicant is added to the water in order to obtain the correct concentrations to be tested. The control and test organisms are placed in the test solutions and the water is not changed for the entirety of the test. Recirculation. A recirculation test exposes the organism to the toxicant in a similar manner as the static test, except that the test solutions are pumped through an apparatus to maintain water quality, but not reduce the concentration of the toxicant in the water; the water is circulated through the test chamber continuously, similar to an aerated fish tank. This type of test is expensive and it is unclear
Rubber mulch is a type of mulch used in gardens and sustainable landscaping, made from recycled rubber. Rubber mulch consists of either waste tire buffings or nuggets of synthetic rubber from tires that are ground up whole, after having their steel bands removed. Any tire can be used to make rubber mulch, including passenger vehicle tires and large truck and trailer tires. Buffings are produced from recycled truck tire tread when the remainder of the worn-down tread is removed from the tire prior to retreading. Buffings are thin slivers of rubber. Nuggets range in size from 3/8 inch to 1 1⁄4 inch. Rubber mulch provides several advantages over plant material based mulches. For landscaping and gardening purposes, both nuggets and buffings insulate soil from heat, allowing a 2 or 3 degrees F higher soil temperature difference over wood mulches. Rubber mulch is beneficial for soil moisture, as rubber is non-porous and does not absorb water on its way through to the soil, it reduces fungus growth and plant growth, becomes a weed barrier, as weed seeds dehydrate in the mulch before reaching the soil.
Neither nuggets nor buffings provide any humus to compacted soil types. Another advantage over plant-material mulches is its elasticity, which gives it a springy quality when used in a thick layer; this makes it a natural choice for playgrounds, where the extra springiness provides additional safety for children when they fall off of playground equipment. Tests have shown; the International Play Equipment Manufacturers Association has certified some rubber mulches for ASTM F1292-09. Rubber mulch is an alternative to wood mulch, reducing the regional and global carbon footprint by reusing materials that would otherwise end up in landfills, its durability can be up to twelve times greater than wood mulch, with wood mulch lasting an average of four seasons. Unlike organic mulch, rubber mulch does not enrich soil or increase soil biodiversity through decomposition, at worst, it leads to soil contamination Some recycled varieties may leach chemicals which are harmful to plants Rubber mulch, like some organic mulch, is a hazard if ignited.
In the US, the Environmental Protection Agency has endorsed the use of recycled rubber to cushion the surfaces of children’s playgrounds. In addition, the EPA studied air and surface samples at four fields and playgrounds that use recycled tires; the limited study, conducted in August through October 2008, found that the concentrations of materials that made up tire crumb were below levels considered harmful. In addition, the overall study protocol and many of the methods were found to be appropriate and could be implemented in the field; the study, did note that due to its limited nature and the large diversity of materials used to make tire crumb, no definitive conclusions could be reached. The Office of Environmental Health Hazard Assessment of the California Environmental Protection Agency tested skin sensitization by playground surfaces made of recycled tires and found no sensitization observed suggesting that these surfaces would not cause skin sensitization in children, nor would they be expected to elicit skin reaction in children sensitized to latex.
ChemRisk, Inc. in Pittsburgh conducted a review of exposure to recycled tire rubber found on playgrounds and synthetic turf fields. They concluded that no adverse human health or ecological health effects are to result from these beneficial reuses of tire materials. Although rubber mulch is regarded as safe, recycled tire rubber leachates do contain certain minerals and compounds which may be ecotoxic in high concentrations. Recycled tire mulch can contain trace amounts of various minerals from the tire manufacturing process and other chemicals that may have been picked up during the tire's service life; the greater the surface area of synthetic rubber waste pellets, the greater the potential for breakdown into harmful constituents. For leached tire debris, the environmental impact of the ingredients zinc and organic toxicants has been demonstrated. Mulch Rubber Retreading Tire Recycling Green Building Plastic mulch New York artificial turf field study The Myth of Rubberized Landscapes Artificial Turf: Exposures to Ground Up Rubber Tires - Athletic Fields, Garden Mulch