Dursban is a product name for the chemicalchlorpyrifos . Chlorpyrifos is one of the class of chemical substance recognize asorganophosphates . These are complex chemical widely used as pesticide in agriculture . TheU.S. Environmental Protection Agency(EPA ) calculate that around 60 million pounds of organophosphates will be applied to approximately 60 million estate of crop in the United States this year . Dursban also has been used in pesticide spray for residential and institutional usage , let in the spray used by professional exterminators . In residential options , chlorpyrifos have been used in termite treatments and lawn tutelage . You will find other organophosphates in the pesticide section of your local home and garden center . Among the brand gens to face for are Malathion and Diazinon .
Dursban , and the quietus of the organophosphate insecticides , work by interrupt the electrochemical appendage that boldness expend to communicate with muscles and with one another . A cardinal chemical substance in communicating between synapses isacetylcholine , a case of chemical squall a neurotransmitter . This chemical is produced by the body , used to " burn down " the neuron , and then is suppress by an enzyme calledcholinesterase .
enzyme work by bonding with particular chemical in a process often illustrated as a key going into a lock ( seeHow Cells Workfor item on enzymes ) . In a normally functioning nerve action , acetylcholine passes a sign ( fire ) between one neuron and another or between a nerve and a brawn receptor . Then cholinesterase binds to the acetylcholine , reserve the nervus to breathe . Dursban alters cholinesterase , preventing it from inactivating acetylcholine . As the acetylcholine build up , the muscles of the consistency become over - stimulated , leading to paralysis and destruction .
Organophosphates were first germinate in the 1800s , but their consequence on animals were n’t discovered until the early 1930s . That issue was put to manipulation in World War II , when organophosphates were used as nerve gas agents in chemical weapons . Dursban , and other organophosphates , are highly toxic to mammals , with a chemical feature that lead them to disperse very slowly once introduced to the body . The symptoms of organophosphate intoxication start with extreme excitability and shaking , and move on to convulsions , paralysis and expiry .
So why does n’t Dursban affect the farmer when he ’s spray his domain for insects ? The answer islethal dose . Lethal dosages for most substances are based on the weight of the animal being give the substance . An grownup human weighs far more than , say , a roach , so a Lucy in the sky with diamonds of Dursban fatal to a bug will be below the level that has a noticeable issue on a human being . Increase the dose to a high-pitched enough point , though , and the substance that wipe out worm will have the same essence on humans . This is one of the reason that lawn services warn homeowners to keep pets and children off the Gunter Grass for a fourth dimension after the lawn has been handle for insects : Since children and pets have miserable body weights than adult , and tend to have their breathing setup closer to the ground , it ’s possible that they would receive a pane of insecticide sufficient to cause some effect , while adults are , in elevation and weight , " above " the level of perniciousness .
The EPA has ordered the use of goods and services of Dursban phased out in the United States . The pesticide has been removed from consumer retail shelves , and will be shorten to very specific commercial-grade applications by 2002 . The phase - out has been grade primarily because of environmental concern regarding mammal and marine animals , and to reduce exposure risks for children .
