Imidacloprid
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Removing backlinks to Bayer Advantage that has been speedily deleted per ([[WP:CSD#G11|CSD G11]]); using [[WP:TW|TW]]
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{{Chembox new
|Reference=<ref>[http://extoxnet.orst.edu/pips/imidaclo.htm Imidacloprid] at Extoxnet</ref>
|ImageFile=Imidacloprid..png
|ImageSize=200px
|IUPACName=''N''-[1-[(6-Chloro-3-pyridyl)methyl]-4,5-dihydroimidazol-2-yl]nitramide
|OtherNames=
|Section1= {{Chembox Identifiers
| CASNo=13826-41-3
| PubChem=86418
| SMILES=C1CN(C(=N1)N[N+](=O)[O-])CC2=CN=C(C=C2)Cl
}}
|Section2= {{Chembox Properties
| Formula=C<sub>9</sub>H<sub>10</sub>ClN<sub>5</sub>O<sub>2</sub>
| MolarMass=255.661
| Appearance=Colorless crystals
| Density=
| MeltingPt=136.4-143.8 °C
| BoilingPt=
| Solubility=0.51 g/L (20 °C)
}}
|Section3= {{Chembox Hazards
| MainHazards=
| FlashPt=
| Autoignition=
}}
}}
'''Imidacloprid''' is an [[insecticide]] manufactured by [[Bayer Cropscience]] (part of [[Bayer|Bayer AG]]). It is sold under a variety of [[trade name]]s including Kohinor, Admire, Advantage, Gaucho, Merit, Confidor, Hachikusan, Premise, Prothor, and Winner.
Imidacloprid was first patented in the United States in U.S. Pat. No. 4,742,060, on [[May 3]] [[1988]], by Nihon Tokushu Noyaku Seizo K.K. of Tokyo, Japan.
In [[France]], its use (as Gaucho) has become controversial in terms of a possible link to derangement of behavior in domesticated [[honeybee]]s. See [[Imidacloprid effects on bee population]].
==Biochemistry==
A chlorinated analog of [[nicotine]], the compound therefore belongs to the class of [[chloronicotinyl]] insecticides, and acts on the [[nicotinic acetylcholine receptor]]; the chlorination inhibits degradation by [[acetylcholine-esterase]]. Imidacloprid is notable for its relatively low [[toxicity]] to most animals other than [[insect]]s due to its specificity for this type of [[Receptor (biochemistry)|receptor]], which is found more often in insect [[nervous system]]s and [[zooplankton]] than that of other animals (exceptions exist; [[earthworm]]s and a few species of [[fish]], for example). This potentially allows for lower concentrations (''e.g.'' 0.05–0.125 lb/acre or 55–140 g/ha) to be used for insect control than other neurotoxins (particularly [[organophosphates]]) and enabling its use in applications as diverse as [[flea treatment]]s for pets, control of [[beetle]] larvae in lawns, eradication or prevention of [[termite]] infestation in buildings, and other uses where animals and people may be exposed. Imidacloprid is, for example, present as a main (or the sole) active ingredient in concentrations between five and ten percent in three out of the four most widely used flea treatment and preventative topical treatments for [[dog]]s in the United States; these manufacturers claim an effective killing persistence of at least four weeks. The compound is also used for flea treatment on [[cat]]s, whose [[liver]]s have only limited detoxification ability compared with dogs and humans.
Imidacloprid is rated as "moderately toxic" acutely by the [[WHO]] and the [[EPA]] (class II or III, requiring a "Warning" or "Caution" label), and a "potential" [[ground water]] contaminant. It is rated as an "unlikely" [[carcinogen]] by the EPA (group E), and is not listed for [[endocrine]], [[reproductive]], or [[developmental]] toxicity, or as a chemical of special concern by any agencies. It is not banned, restricted, cancelled, or illegal to import in any country. Tolerances for imidacloprid residue in food range from 0.02 mg/kg in eggs to 3.0 mg/kg in [[hops]].
Animal toxicity is similar to that of the parent compound, nicotine; [[fatigue (physical)|fatigue]], [[Muscle contraction|twitch]]ing, [[cramp]]s, and [[Fatigue (medical)|weakness]] leading to [[asphyxia]]. The oral [[LD50]] (the dose which resulted in mortality of half of the test animals) of imidacloprid is 450 mg/kg body weight in [[rat]]s and 131 mg/kg in [[mouse|mice]]; the 24-hour [[dermal]] LD50 in rats is greater than >5000 mg/kg. It is not irritating to eyes or skin in [[rabbit]]s and [[guinea pig]]s (although some commercial preparations contain [[clay]] as an inert ingredient, which may be an [[Irritation|irritant]]). The acute [[inhalation]] LD50 in rats was not reached at the greatest attainable concentrations, 69 milligrams per cubic meter of air as an aerosol, and 5,323 mg/m³ of air as a dust. In rats subjected to a two year feeding study, no observable effect was seen at 100 ppm{{vague|date=March 2008}}. At 300 ppm{{vague|date=March 2008}} females showed decreased body weight gain and males showed increased [[thyroid]] [[lesion]]s, while females showed increased thyroid lesions at 900 ppm. In a one year feeding study in dogs, no observable effect was seen at 1,250 ppm, while levels up to 2,500 ppm led to [[hypercholesterolemia]] and elevated [[liver]] [[Cytochrome P-450#Drug Metabolism|cytochrome p-450 measurements]]. Reproductive studies in rats resulted in no observable effect at 100 ppm and decreased pup weight at 250 ppm; developmental toxicity studies in rats showed no observable effect at 30 (mg/kg)/day and skeletal anomalies at 100 (mg/kg)/day, while in rabbits no observable effect was detected at 24 (mg/kg)/day and skeletal abnormalities at 72 (mg/kg)/day. Imidacloprid was negative for [[mutagenicity]] in 21 out of 23 different laboratory tests, but was positive for [[chromosome|chromosomal]] changes in human [[lymphocyte]]s and for [[genotoxic]]ity in [[CHO cell]]s. No [[carcinogenicity]] was seen in rats fed up to 1,800 mg/kg of imidacloprid for two years. <ref> [http://pmep.cce.cornell.edu/profiles/extoxnet/haloxyfop-methylparathion/imidacloprid-ext.html Cornell Extension Toxicology Network]</ref>
Imidacloprid has low [[vapor pressure]]. The chemical breaks down to [[inorganic]] molecules by both [[photolysis]] and [[microbe|microbial]] action, in the air and with a [[half-life]] of 30 days in water and 27 days in [[soil]] [[Hypoxia (environmental)|anaerobic]]ally. Although it is not "persistent" in the technical sense since it does degrade, it can have a half-life in soil under [[Oxygen|aerobic]] conditions of as long as 997 days, which is the cause of the concern over possible water contamination as it gradually leaches out of a hypothetical soil reservoir. The manufacturer maintains that, when applied according to instructions, such long-term contamination is only found as the result of "repetitive application over several years" and spread to beneficial insect populations is minimal. In the body, 96% of the chemical is eliminated within 48 hours; the most important degradation product in the body is 6-chloronicotinic acid, another nicotinic neurotoxin with similar properties. Imidacloprid has, however, been reported to degrade into toxic, persistent, 2-chloro[[pyridine]].
==Uses==
The most widely used applications for imidacloprid in [[California]] are pest control in structures, [[lawn|turf]] pest control, [[grape]] growing, and head and leaf [[lettuce]] growing. Other widespread crop uses are [[rice]], grains/[[cereal]]s including corn ([[maize]]), [[potato]]es, [[vegetable]]s, [[sugar beet]]s, [[fruit]], [[cotton]], and hops. Target insects include sucking insects (''e.g.'' [[aphid]]s, [[whitefly|whiteflies]], [[leafhopper]]s and [[planthopper]]s, [[thrip]]s, [[Scale insect|scale]]s, [[mealybug]]s, [[Hemiptera|bugs]], [[psyllid]]s, and [[phylloxera]]), [[beetle]]s (''e.g.'' [[longhorn beetle]]s, [[leaf beetle]]s, [[Colorado potato beetle]]s, rice water-[[weevil]]s, [[wireworm]]s, [[Larva|grub]]s, and [[flea beetle]]s), and others (''e.g.'' [[lepidoptera|lepidopterous]] [[leafminer]]s, some [[diptera]], [[termite]]s, [[locust]]s, and [[flea]]s).
When used for seed treatments, it is sold under the trade names Akteur, Amigo, Baytan Secur, Chinook, El Hombre, Escocet, Gaucho, Gaucho Blé, Gaucho CS, Gaucho Maícero, Gaucho MZ, Gaucho Orge, Gaucho Primo, '''Gaucho T,''' Gaucho MT, Gaucho XT, Genesis, Faibel, Ferial Blé, Férial Orge, Imprimo, Manta Plus, Monceren Extra, Monceren G, Monceren GT, Montur, Prestige, Prestige M, Raxil Secur, Seed-one, Sibutol Secur, Yunta and Zorro FS 236.
When used on citrus, coffee, cotton, fruits, grapes, potatoes, rice, soybeans, sugarcane, tobacco and vegetables as an insecticide spray, it is sold under the trade names Admire, Confidor, Connect, Evidence, Leverage, Muralla, Provado and Trimax.
It is marketed as Premise for termite control and Advantage in the US and Europe for flea control on pets. It is also sold under the trade names Merit, Admire, Confidor and Winner, as well as Hachikusan (in Japan).
.47 to .94oz of pure Imidacloprid may be mixed w/ 4 gallons of water to cover 10 linear feet for purposes of treating subterranean termites.
==Proper use of Advantage==
When using Advantage flea control on animals, make sure to use a soap-free shampoo. The company's question hotline states that it is necessary to use a pet soap-free shampoo, otherwise the poison will be removed. However, Bayer's website claims the product remains effective even after shampooing.<ref>[http://advantage.petparents.com/compare.cfm Advantage] at PetParents.com</ref>
==A systemic insecticide==
Imidacloprid is taken up by plant [[root]]s and diffuses in the plant [[vascular system]], where insects ingest it by sucking the plant fluids. The products Confidor and Admire are meant for application via [[irrigation]], application to the soil, or on [[foliage]], while Gaucho is intended for use as a [[seed]] dressing, applied to the seed before sowing.
Seed applied insecticides are often used to deal with numerous insects as they are easy to use and comparable in cost to most traditional insecticides used at sowing time. Some also indicate that it might be better for the environment because less chemical is required than for broadcast or banded applications, or at least because less chemical is sprayed in the air. However, some note that the use of seed-applied insecticides at each season implies the chemical is used whether there is need to fight insects or not.
Imidacloprid is receiving increased attention as a possible factor in [[Colony Collapse Disorder]], a mysterious condition that causes sudden death of [[honey bee]] populations. Mass die-offs of bees threaten [[pollination management|pollination]] of food crops in the USA and Europe.
== See also ==
*[[Colony collapse disorder]]
*[[Pesticide toxicity to bees]]
*[[Imidacloprid effects on bee population]]
==References==
{{reflist}}
== Sources ==
*[http://www.pesticideinfo.org/Detail_Chemical.jsp?Rec_Id=PC35730 PAN Pesticides Database]
==External links==
*[http://www.flora.org/healthyottawa/merit-pesticide-insecticide-grub.htm Breakdown Chart of Imidacloprid forming toxic 2-chloro pyridine]
*[http://www.sierraclub.ca/national/programs/health-environment/pesticides/imidacloprid-fact-sheet.shtml Imidacloprid Fact Sheet, with 18 References, from the Sierra Club of Canada]
*[http://www.beekeeping.com/articles/us/imidacloprid_bayer.htm Bayer's "Expert Overview"]
[[Category:Insecticides]]
[[Category:Imidazolines]]
[[Category:Pyridines]]
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