MULLER Paul( Swiss chemist, Nobel Prize in Physiology or Medicine, 1948)
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Biography MULLER Paul
January 12, 1899, Mr.. - October 13, 1965
Swiss chemist, Paul Hermann Mц+ller was born in Oltenia, the son of Gottlieb Mueller, an employee of the Swiss railways, and Fanny (Leypoldt) Muller. His early years Paul spent in Lenburge (District Argo), the home of his father. When he was five years old, the family moved to Basel, where Paul received his education in local school. Leaving school at seventeen, he began working at a chemical plant, and next year he became an assistant chemist in the laboratory of the company Lonzo. This experience prompted him to research in 1919. go to Basel University to study chemistry in 1925, defended a thesis on organic chemistry of dyes, he received the title of Doctor of Philosophy. After graduating from the University of M. was hired in the company CJR. Dzheydzhi, one of the largest chemical corporations. In Basel, he had little interest in botany, and in the company Dzheydzhi his first task has been to explore the properties of natural products of plant. Over the next three years, M. received some valuable tanning agents, then his attention was drawn to the disinfectants used primarily for the protection of seed plants. In 1935. he began to study insecticides (means for control of insects). Although there was a large amount of scientific literature on this issue and recommendations for their use of available insecticides actually for sale was not. Of the few existing M. not find those that could be compared with known insecticide (arsenate, pyrethrum or rotenone).
. Arsenates are artificially synthesized chemicals, while pyrethrum and rotenone - natural plant extracts
. Each of the known insecticides has drawbacks. Arsenates, such as toxic to humans, and derivatives of plants but not toxic, but expensive. In addition, the effects of the use of these compounds are short-lived. M. sought to obtain a synthetic insecticide that kills insects on contact, but not toxic to humans and plants, cheap and chemically stable.
With experimenters led by M. conducted biological research, which included testing of insecticidal properties of hundreds of chemical compounds. Researchers at Dzheydzhi synthesizing one compound after another, trying unsuccessfully to predict the insecticidal activity of compounds on its structure. By September 1939. they created difeniltrihloretan - a substance in which two benzene rings connected by a carbon atom attached to it with three chlorine atoms. This substance proved to be an effective contact insecticide, and its chemical structure - stable. M. knew that similar difenialnye compounds containing sulfur instead of the central carbon atom, represent an effective oral poison, if the chlorine atoms in them are located next to and in accordance with this he synthesized in 1939. 4,4-dichloro-difeniltrihloretan (DDT); Dzheydzhi company has patented the drug in 1940, conducted field tests, and in 1942. He went on sale.
During the Second World War supplies to the Allied Powers of natural insecticides, most of which were produced in tropical countries, have been reduced or stopped completely, while the demand for them was intense. Typhus and malaria, caused by insects - the two biggest health problems facing the Allies, in connection with the fact that against these diseases there is no vaccine. Studies Ronald Ross and Charles Nicolle, showed that the incidence of malaria and typhoid fever may be suspended if it is possible to limit the spread of mosquitoes and lice, which are the carriers of these diseases. New insecticide DDT seemed ideal for this purpose. Its toxicity to people is so low that the drug is supposed to spray directly on the body to prevent the occurrence of typhoid. He was also quite affordable, allowing the use of DDT for spraying on the whole island in the Pacific Ocean before the landing of U.S. forces on shore, thus preventing malaria. He was so stable that after a single spraying remained effective for several months.
Successful application of DDT during the war to combat malaria and typhus made M. one of the main candidates for the Nobel Prize in Physiology or Medicine, which he received in 1948. 'for the discovery of the high efficiency of DDT as a contact poison'.
Over the next two decades of unparalleled value of DDT as an insecticide was confirmed again and again, especially using it in tropical countries. This substance not only prevents the occurrence of malaria, the most common tropical disease, but also helped to dramatically increase the yield of new types of crops, are selected by Norman Borlougom.
. Only later were found adverse action of DDT
. One of the features of this tool that has made him so attractive at first, - stability compared with natural plant insecticides. From the beginning, M. realized that this stability is fraught with certain risks. Not gradually disintegrating into harmless components, DDT accumulates in the soil, water and animal organism. In addition, the drug is a broad-spectrum insecticide, and, in addition to pests, kills beneficial insects, such as bees. Concerns about side effects of DDT increased over the 60-ies., And in 1972. its widespread use in the United States was prohibited. Adverse effects of DDT and the harm caused by this powerful insecticide to the environment, led to the book Rachel Carson 'Silent spring' ( 'Silent Spring').
In 1927, Mr.. M. married Friedel Ryugzegger; they were born two sons and a daughter. M. resigned from the company in 1961 Dzheydzhi. and the next four years he worked in a private laboratory that is equipped at his home in Obersvile near Basel. He died on October 13, 1965, Mr.. after a short illness.