Insecticide DDT

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Insecticide DDT

• Václav Szmek
• Jirí Šido

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Physical and chemical properties
DDT DDT
Chemical name 4,4'-(2,2,2-trichloroethane-1,1-diyl)bis(chlorobenzene)
Chemical formula C14H9Cl5
Molecular mass 354.49 g/mol
Melting point 108.5 C
Boiling point 260 C
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Powder prášekodour zápachenvironment
okolí, ovzduší

• DDT is a white, crystalline powder with a weak
  odour.
• It shows low solubility in water and high
  soubility in organic solvents, fat and oils.
• It doesn't break down in the environment or in
  organisms.

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Preparation of DDT and its qualities

• DDT is created by the reaction of
  trichloroethanol with chlorbenzene (C6H5Cl).
  Trade or other names for DDT include Anofex,
  Cesarex, Chlorophenothane.
• DDT has potent insecticidal properties it kills
  by opening sodium channels in insect neurons,
  causing the neuron to fire spontaneously.
• DDT was responsible for eradicating malaria from
  Europe and North America, and was also
  extensively used as an agricultural insecticide
  after 1945

• Quality vlastnost potent silný, úcinný
• Extensively rozsáhle eredicate - vyhubit

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History of DDT

• DDT was the first modern pesticide, was first
  synthesized in 1873 by Othmar Ziedler .
• Insecticidal properties were discovered in 1939,
  by the Swiss scientist Paul Hermann Paul Hermann
  Müller
• It was used extensively during World war II by
  Allied troops and certain civilian populations to
  control insect typhus and malaria vectors (as a
  result nearly eliminating typhus).
• DDT was also extensively used as an agricultural
  insecticide after 1945.
• By the 1950s, in some uses, doses of DDT and
  other insecticides had to be doubled or tripled
  as resistant insect strains developed.

• Properties vlastnosti extensive casto
• Certain zarucený, spolehlivý strain namáhat,
  napínat

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Environmental impact

• DDT is a Persistent Organic Pollutant and very
  highly persistent in the environment. Routes of
  loss and degradation include runoff,
  volatilization, photolysis and biodegradation
  (aerobic and anaerobic). These processes
  generally occur slowly. Breakdown products in the
  soil environment are DDE (1,1-dichloro-2,2-bis(p-d
  ichlorodiphenyl)ethylene) and DDD
  (1,1-dichloro-2,2-bis(p-chlorophenyl)ethane),
  which are also highly persistent and have similar
  chemical and physical properties.

• Persistent odolná
• Pollutant-spad, znecištující látka
• Occur prihodit se
• Route smer
• Loss ztráta
• Runoff-odtok, splach
• Volatilization- tekání, vyprchání, vyparení

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• DDT is highly toxic to aquatic life, including
  crayfish, daphnids, sea shrimp and many species
  of fish. DDT may be moderately toxic to some
  amphibian species, especially in the larval
  stages. In addition to acute toxic effects, DDT
  may bioaccumulate significantly in fish and other
  aquatic species, leading to long-term exposure.

• DDT is not particularly toxic to humans, compared
  to other widely used pesticides.
• Crayfish rak daphnids-plankton sea
  shrimp-kreveta Amphibian- obojživelný

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Arguments for and against DDT

• Since the ban, two million people a year have
  died unnecessarily from malaria, mostly children.
  The ban has caused more than fifty million
  needless deaths. Banning DDT killed more people
  than Hitler
• One of the pro-DDT arguments is that the
  treatment was used long enough to eliminate
  insect-borne diseases in the West but now that
  it's only needed in poorer countries in Africa,
  Asia and elsewhere it's been banned.

• Ban zákaz
• Caused zpusobil
• Treatment lécba, zacházení

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Thank you for attention