Deltamethrin

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Deltamethrin
Deltamethrin
Deltamethrin
Identifiers
CAS number 52918-63-5 YesY
ChemSpider 37079 YesY
UNII 2JTS8R821G YesY
KEGG D07785 YesY
ChEBI CHEBI:4388 YesY
ChEMBL CHEMBL1593566 N
ATC code P03BA03,QP53AC11
Jmol-3D images Image 1
Properties
Molecular formula C22H19Br2NO3
Molar mass 505.20 g mol−1
Density 1.5 g cm−3
Melting point 98 °C (208 °F; 371 K)
Boiling point 300 °C (572 °F; 573 K)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
 N (verify) (what is: YesY/N?)
Infobox references

Deltamethrin is a pyrethroid ester insecticide.

Usage[edit]

Deltamethrin products are among the most popular and widely used insecticides in the world[citation needed] and have become very popular with pest control operators and individuals in the United States.[1] This material is a member of one of the safest classes of pesticides: synthetic pyrethroids. This pesticide is highly toxic to aquatic life, particularly fish, and therefore must be used with extreme caution around water. Although generally considered safe to use around humans, it is still neurotoxic to humans. Deltamethrin is able to pass from a woman's skin through her blood and into her breast milk.[2]

There are many uses for deltamethrin, ranging from agricultural uses to home pest control. Deltamethrin has been instrumental in preventing the spread of diseases carried by tick-infested prairie dogs, rodents and other burrowing animals[citation needed]. It is helpful in eliminating and preventing a wide variety of household pests, especially spiders, fleas, ticks, carpenter ants, carpenter bees, cockroaches and bed bugs. Deltamethrin is also one of the primary ingredients in ant chalk.

Production[edit]

Deltamethrin is a pyrethroid composed of a single isomer of 8 stereoisomers selectively prepared by the esterification of (1R,3R)- or cis-2,2-dimethyl-3-(2,2-dibromovinyl)cyclopropanecarboxylic acid with (alpha,S)- or (+)-alpha-cyano-3-phenoxybenzyl alcohol or by selective recrystallization of the racemic esters obtained by esterification of the (1R,3R)- or cis-acid with the racemic or (alpha-R, alpha-S, or alpha-R/S)- or + or − alcohol.

Malaria control[edit]

Deltamethrin plays key role in controlling malaria vectors, and is used in the manufacture of long-lasting insecticidal mosquito nets. It is used as one of a battery of pyrethroid insecticides in control of malarial vectors, particularly Anopheles gambiae, and whilst being the most employed pyrethroid insecticide, can be used in conjunction with, or as an alternative to, permethrin, cypermethrin and other organophosphate-based insecticides, such as malathion and fenthion. Resistance to deltamethrin (and its counterparts) is now extremely widespread and threatens the success of worldwide vector control programmes.

Resistance to deltamethrin[edit]

Resistance has been characterised in several insects, including important vectors of malaria like the mosquito Anopheles gambiae as well as non-disease carrying pests like bed bugs.

Mosquitoes[edit]

Methods of resistance include thickening of the cuticle of the insect to limit permeation of the insecticide, metabolic resistance via overexpression of metabolising P450 mono-oxygenases and glutathione-S-transferases, and the knockdown resistance (kdr) sodium channel mutations which render the action of insecticides ineffectual, even when co-administered with piperonyl butoxide. Characterisation of the different forms of resistance among mosquitoes has become a top priority in groups studying tropical medicine due to the high mortality of those who reside in endemic areas.[3]

Bed Bugs[edit]

Two mutations, the Valine to Leucine mutation (V419L) and the Leucine to Isoleucine mutation (L925I) in voltage-gated sodium channel α-subunit gene, have been identified as responsible for knockdown resistance to deltamethrin in bed bugs. One study found that 88% of bed bug populations in the US had one, the other, or both mutations, meaning that deltamethrin resistance among bed bugs is currently making this insecticide obsolete.[4]

Poisoning[edit]

In humans[edit]

While deltamethrin is easy to use and in some cases very effective, it should always be treated with caution. It should be applied according to the instructions that come with the insecticide. When care is not taken, deltamethrin poisoning can occur.

Since deltamethrin is a neurotoxin, it temporarily attacks (in medical terms, "insults") the nervous system of any animal with which it comes into contact. Skin contact can lead to tingling or reddening of the skin local to the application. If taken in through the eyes or mouth, a common symptom is facial paraesthesia, which can feel like many different abnormal sensations, including burning, partial numbness, "pins and needles", skin crawling, etc. There are no reports indicating that chronic intoxication from pyrethroid insecticides causes motor neuron damage or motor neuron disease.[5] However, in 2011, a case report was published that demonstrated pathologically proven motor-neuron death in a Japanese woman after acute massive ingestion of pesticides containing pyrethroids and organochlorine. [6]

Recently, in South Africa, residues of deltamethrin were found in breast milk, together with DDT, in an area that used DDT treatment for malaria control, as well as pyrethroids in small-scale agriculture.[7]

There are no antidotes, and treatment must be symptomatic, as approved by a physician. Over time, deltamethrin is metabolized, with a rapid loss of toxicity, and passed from the body. A poison control center should be contacted in the event of an accidental poisoning.

In domestic animals[edit]

Cases of toxicity have been observed in cattle, following use of agricultural deltamethrin preparation in external application in tick control. Symptoms appeared 36 hours after the application, and included muscular tremors that lead to decubitus 12 hours later. After 12 hours, there was spontaneous recovery and the animal could stand up again, although the muscular tremors persisted. The body temperature was then 38.3°C. (normal range 38.0 to 39.5°C.).[citation needed]

References[edit]

  1. ^ "Deltamethrin Odorless Synthetic Pyrethroid Insecticides". PestProducts.com. Retrieved 2008-09-26. 
  2. ^ Bouwman, B. Sereda and H.M. Meinhardt, H.; B. Sereda and H.M. Meinhardt (December 2006). "Simultaneous presence of DDT and pyrethroid residues in human breast milk from a malaria endemic area in South Africa". Environmental Pollution 144 (3): 902–917. doi:10.1016/j.envpol.2006.02.002. PMID 16564119. Retrieved 2008-09-26. 
  3. ^ Muller, Pie, et al. (2008). Field caught Permethrin-Resistant Anopheles gambiae overexpress CYP6P3, a P450 that metabolises pyrethroids,PLoS Genetics 4(11)).
  4. ^ Zhu, F.; Wigginton, J.; Romero, A.; Moore, A.; Ferguson, K.; Palli, R.; Potter, M. F.; Haynes, K. F.; Palli, S. R. (2010). "Widespread distribution of knockdown resistance mutations in the bed bug,Cimex lectularius(Hemiptera: Cimicidae), populations in the United States". Archives of Insect Biochemistry and Physiology: n/a. doi:10.1002/arch.20355. 
  5. ^ Doi, et al (2006). "Motor neuron disorder simulating ALS induced by chronic inhalation of pyrethroid insecticides". Neurology 67 (10). pp. 1894–1895. doi:10.1212/01.wnl.0000244489.65670.9f. 
  6. ^ Doi, et al (2006). "Motor neuron disorder simulating ALS induced by chronic inhalation of pyrethroid insecticides". Neurology 67 (10). pp. 1894–1895. doi:10.1212/01.wnl.0000244489.65670.9f. 
  7. ^ Bouwman, B. Sereda and H.M. Meinhardt, H.; B. Sereda and H.M. Meinhardt (December 2006). "Simultaneous presence of DDT and pyrethroid residues in human breast milk from a malaria endemic area in South Africa". Environmental Pollution 144 (3): 902–917. doi:10.1016/j.envpol.2006.02.002. PMID 16564119. Retrieved 2008-09-26. 

External links[edit]