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Ddt
Dichlorodiphenyltrichloroethane, commonly known as DDT, is a colorless, tasteless, and almost odorless crystalline chemical compound, an organochloride. Originally developed as an insecticide, it became infamous for its environmental impacts. DDT was first synthesized in 1874 by the Austrian chemist Othmar Zeidler. DDT's insecticidal action was discovered by the Swiss chemist Paul Hermann Müller in 1939. DDT was used in the second half of World War II to limit the spread of the insect-borne diseases malaria and typhus among civilians and troops. Müller was awarded the Nobel Prize in Physiology or Medicine in 1948 "for his discovery of the high efficiency of DDT as a contact poison against several arthropods". By October 1945, DDT was available for public sale in the United States. Although it was promoted by government and industry for use as an agricultural and household pesticide, there were also concerns about its use from the beginning. Opposition to DDT was focused by t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silent Spring
''Silent Spring'' is an environmental science book by Rachel Carson. Published on September 27, 1962, the book documented the environmental harm caused by the indiscriminate use of pesticides. Carson accused the chemical industry of spreading disinformation, and public officials of accepting the industry's marketing claims unquestioningly. In the late 1950s, Carson began to work on environmental conservation, especially environmental problems that she believed were caused by synthetic pesticides. The result of her research was ''Silent Spring'', which brought environmental concerns to the American public. The book was met with fierce opposition by chemical companies, but it swayed public opinion and led to a reversal in U.S. pesticide policy, a nationwide ban on DDT for agricultural uses, and an environmental movement that led to the creation of the U.S. Environmental Protection Agency.Paull, John (2013"The Rachel Carson Letters and the Making of Silent Spring", Sage Open, 3 ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rachel Carson
Rachel Louise Carson (May 27, 1907 – April 14, 1964) was an American marine biologist, writer, and conservationist whose influential book ''Silent Spring'' (1962) and other writings are credited with advancing the global environmental movement. Carson began her career as an aquatic biologist in the U.S. Bureau of Fisheries, and became a full-time nature writer in the 1950s. Her widely praised 1951 bestseller '' The Sea Around Us'' won her a U.S. National Book Award, recognition as a gifted writer and financial security. Her next book, ''The Edge of the Sea'', and the reissued version of her first book, '' Under the Sea Wind'', were also bestsellers. This sea trilogy explores the whole of ocean life from the shores to the depths. Late in the 1950s, Carson turned her attention to conservation, especially some problems she believed were caused by synthetic pesticides. The result was the book ''Silent Spring'' (1962), which brought environmental concerns to an unprecedente ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paul Hermann Müller
Paul Hermann Müller, also known as Pauly Mueller (12 January 1899 – 13 October 1965), was a Swiss chemist who received the 1948 Nobel prize in Physiology or Medicine for his 1939 discovery of Insecticide, insecticidal qualities and use of DDT in the control of Disease vector, vector diseases such as malaria and yellow fever. Early life and education Müller was born on 12 January 1899 in Olten, Solothurn, to Gottlieb and Fanny (née Leypoldt or Leypold ) Müller. He was the oldest of four children. His father worked for the Swiss Federal Railways and the family first moved to Lenzburg in Aargau and then to Basel. Müller went to the local primary school (volksschule) and later to the lower and upper "realschule". In that time, he had a small laboratory where he developed photographic plates and built radio equipment. In 1916 he left school due to bad grades and started to work as a laboratory assistant at Dreyfus. The next year he became an assistant chemist in the scienti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dicofol
Dicofol is an organochlorine pesticide that is chemically related to DDT. Dicofol is a miticide that is very effective against spider mite. One of the intermediates used in its production is DDT. This has caused criticism by many environmentalists; however, the World Health Organization classifies dicofol as a Level II, "moderately hazardous" pesticide. It is known to be harmful to aquatic animals, and can cause eggshell thinning in various species of birds. Difference between dicofol and DDT Dicofol is structurally similar to DDT. It differs from DDT by the replacement of the hydrogen (H) on C-1 by a hydroxyl (OH) functional group. One of the intermediates used in its production is DDT. Chemistry Dicofol is usually synthesized from technical DDT. During the synthesis, DDT is first chlorinated to an intermediate, Cl-DDT, followed by hydrolyzing to dicofol. After the synthesis reaction, DDT and Cl-DDT may remain in the dicofol product as impurities. * Formula: C14H9Cl5O * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insecticide
Insecticides are substances used to kill insects. They include ovicides and larvicides used against insect eggs and larvae, respectively. Insecticides are used in agriculture, medicine, industry and by consumers. Insecticides are claimed to be a major factor behind the increase in the 20th-century's agricultural productivity. Nearly all insecticides have the potential to significantly alter ecosystems; many are toxic to humans and/or animals; some become concentrated as they spread along the food chain. Insecticides can be classified into two major groups: systemic insecticides, which have residual or long term activity; and contact insecticides, which have no residual activity. The mode of action describes how the pesticide kills or inactivates a pest. It provides another way of classifying insecticides. Mode of action can be important in understanding whether an insecticide will be toxic to unrelated species, such as fish, birds and mammals. Insecticides may be repellent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stockholm Convention On Persistent Organic Pollutants
Stockholm Convention on Persistent Organic Pollutants is an international environmental treaty, signed on 22 May 2001 in Stockholm and effective from 17 May 2004, that aims to eliminate or restrict the production and use of persistent organic pollutants (POPs). History In 1995, the Governing Council of the United Nations Environment Programme (UNEP) called for global action to be taken on POPs, which it defined as "chemical substances that persist in the environment, bio-accumulate through the food web, and pose a risk of causing adverse effects to human health and the environment". Following this, the Intergovernmental Forum on Chemical Safety (IFCS) and the International Programme on Chemical Safety (IPCS) prepared an assessment of the 12 worst offenders, known as the ''dirty dozen''. The INC met five times between June 1998 and December 2000 to elaborate the convention, and delegates adopted the Stockholm Convention on POPs at the Conference of the Plenipotentiaries co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Environmental Impact Of Pesticides
The environmental effects of pesticides describe the broad series of consequences of using pesticides. The unintended consequences of pesticides is one of the main drivers of the negative impact of modern industrial agriculture on the environment. Pesticides, because they are toxic chemicals meant to kill pest species, can affect non-target species, such as plants, animals and humans. Over 98% of sprayed insecticides and 95% of herbicides reach a destination other than their target species, because they are sprayed or spread across entire agricultural fields. Other agrochemicals, such as fertilizers, can also have negative effects on the environment. The negative effects of pesticides are not just in the area of application. Runoff and pesticide drift can carry pesticides into distant aquatic environments or other fields, grazing areas, human settlements and undeveloped areas. Other problems emerge from poor production, transport, storage and disposal practices.Tashkent (1998)Pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Malaria
Malaria is a mosquito-borne infectious disease that affects humans and other animals. Malaria causes symptoms that typically include fever, tiredness, vomiting, and headaches. In severe cases, it can cause jaundice, seizures, coma, or death. Symptoms usually begin ten to fifteen days after being bitten by an infected mosquito. If not properly treated, people may have recurrences of the disease months later. In those who have recently survived an infection, reinfection usually causes milder symptoms. This partial resistance disappears over months to years if the person has no continuing exposure to malaria. Malaria is caused by single-celled microorganisms of the ''Plasmodium'' group. It is spread exclusively through bites of infected ''Anopheles'' mosquitoes. The mosquito bite introduces the parasites from the mosquito's saliva into a person's blood. The parasites travel to the liver where they mature and reproduce. Five species of ''Plasmodium'' can infect and be spread by h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bald Eagle
The bald eagle (''Haliaeetus leucocephalus'') is a bird of prey found in North America. A sea eagle, it has two known subspecies and forms a species pair with the white-tailed eagle (''Haliaeetus albicilla''), which occupies the same niche as the bald eagle in the Palearctic. Its range includes most of Canada and Alaska, all of the contiguous United States, and northern Mexico. It is found near large bodies of open water with an abundant food supply and old-growth trees for nesting. The bald eagle is an opportunistic feeder which subsists mainly on fish, which it swoops down upon and snatches from the water with its talons. It builds the largest nest of any North American bird and the largest tree nests ever recorded for any animal species, up to deep, wide, and in weight. Sexual maturity is attained at the age of four to five years. Bald eagles are not actually bald; the name derives from an older meaning of the word, "white headed". The adult is mainly brown with a white ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organochloride
An organochloride, organochlorine compound, chlorocarbon, or chlorinated hydrocarbon is an organic compound containing at least one covalent bond, covalently bonded atom of chlorine. The chloroalkane class (alkanes with one or more hydrogens substituted by chlorine) provides common examples. The wide structural variety and divergent chemical properties of organochlorides lead to a broad range of names, applications, and properties. Organochlorine compounds have wide use in many applications, though some are of profound environmental concern, with 2,3,7,8-Tetrachlorodibenzodioxin, TCDD being one of the most notorious. Physical and chemical properties Chlorination reaction, Chlorination modifies the physical properties of hydrocarbons in several ways. These compounds are typically denser than water due to the higher atomic weight of chlorine versus hydrogen. Aliphatic organochlorides are often alkylating agents as chlorine can act as a leaving group, which can result in cellular dam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bald Eagle
The bald eagle (''Haliaeetus leucocephalus'') is a bird of prey found in North America. A sea eagle, it has two known subspecies and forms a species pair with the white-tailed eagle (''Haliaeetus albicilla''), which occupies the same niche as the bald eagle in the Palearctic. Its range includes most of Canada and Alaska, all of the contiguous United States, and northern Mexico. It is found near large bodies of open water with an abundant food supply and old-growth trees for nesting. The bald eagle is an opportunistic feeder which subsists mainly on fish, which it swoops down upon and snatches from the water with its talons. It builds the largest nest of any North American bird and the largest tree nests ever recorded for any animal species, up to deep, wide, and in weight. Sexual maturity is attained at the age of four to five years. Bald eagles are not actually bald; the name derives from an older meaning of the word, "white headed". The adult is mainly brown with a white ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peregrine Falcon
The peregrine falcon (''Falco peregrinus''), also known as the peregrine, and historically as the duck hawk in North America, is a Cosmopolitan distribution, cosmopolitan bird of prey (Bird of prey, raptor) in the family (biology), family Falconidae. A large, Corvus (genus), crow-sized falcon, it has a blue-grey back, barred white underparts, and a black head. The peregrine is renowned for its speed, reaching over during its characteristic hunting stoop (high-speed dive), making it the fastest bird in the world, as well as the Fastest animals, fastest member of the animal kingdom. According to a ''National Geographic (U.S. TV channel), National Geographic'' TV program, the highest measured speed of a peregrine falcon is . As is typical for avivore, bird-eating raptors, peregrine falcons are Sexual dimorphism, sexually dimorphic, with females being considerably larger than males. The peregrine's breeding range includes land regions from the Arctic tundra to the tropics. It can b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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