Dimethoate

Last updated
Dimethoate
Dimethoate Structural Formulae .V.1.svg
Dimethoate 3D BS.png
Names
Preferred IUPAC name
O,O-Dimethyl S-[2-(methylamino)-2-oxoethyl] phosphorodithioate
Other names
O,O-dimethyl S-methylcarbamoylmethyl phosphorodithioate
Phosphorodithioic acid, O,O-Dimethyl S-(2-(methylamino)-2-oxoethylyl)ester
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.000.437 OOjs UI icon edit-ltr-progressive.svg
KEGG
PubChem CID
UNII
  • InChI=1S/C5H12NO3PS2/c1-6-5(7)4-12-10(11,8-2)9-3/h4H2,1-3H3,(H,6,7) Yes check.svgY
    Key: MCWXGJITAZMZEV-UHFFFAOYSA-N Yes check.svgY
  • InChI=1/C5H12NO3PS2/c1-6-5(7)4-12-10(11,8-2)9-3/h4H2,1-3H3,(H,6,7)
    Key: MCWXGJITAZMZEV-UHFFFAOYAB
  • O=C(NC)CSP(=S)(OC)OC
Properties
C5H12NO3PS2
Molar mass 229.26 g/mol
AppearanceGrey-white crystalline solid
Density 1.3 g/cm3, solid
Melting point 43 to 45 °C (109 to 113 °F; 316 to 318 K)
Boiling point 117 °C (243 °F; 390 K) at 10 Pa
2.5 g/100 ml
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
Highly toxic
GHS labelling:
GHS-pictogram-exclam.svg [1]
H302, H312 [1]
P280 [1]
Flash point 107 °C (225 °F; 380 K)
Safety data sheet (SDS) External MSDS
Related compounds
malathion
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Dimethoate is a widely used organophosphate insecticide and acaricide. It was patented and introduced in the 1950s by American Cyanamid. Like other organophosphates, dimethoate is an acetylcholinesterase inhibitor which disables cholinesterase, an enzyme essential for central nervous system function. It acts both by contact and through ingestion. It is readily absorbed and distributed throughout plant tissues, and is degraded relatively rapidly. [2] One of the breakdown products of dimethoate is omethoate, a potent cholinesterase inhibitor, is ten times more toxic than its parent compound. [3]

Contents

Uses

Dimethoate is a general use insecticide for combatting insects such as aphids, mites, beetles, weevils, and leafhoppers. Dimethoate is formulated as emulsifiable concentrates or wettable powders to be applied primarily as foliar sprays. The majority of the approximately 800.000 kg (1.8 million pounds) of dimethoate used annually in the U.S. is accounted for by applications on alfalfa, wheat, cotton, and corn crops. In 2005, dimethoate usage was cancelled in the U.S. for use on apples, broccoli raab, cabbage, collards, grapes, head lettuce, and spinach due to being identified as significant dietary risk contributors. [4] Dimethoate also has applications as a form of botfly and mite control in livestock. [5] As of 2000, dimethoate is cancelled for usage in residential and non-agriculture applications in the U.S [4] [3]

Environment

Dimethoate is relatively non-persistent, but highly mobile in the environment due to its high solubility in water and low adsorption in soil. [4] [6] The half-life of dimethoate in soil has been shown to range from 2.5 to 31 days depending on the type of soil and its moisture content. [6] The half-life of dimethoate is shorter in moist soil due the action of microbial degradation. [5] Breakdown of dimethoate by hydrolysis in water is highly dependent on temperature and pH, with the half-life ranging from 12 to 423 days. [6]

Health effects

Routes of exposure

Exposure of the general population to dimethoate and its breakdown product omethoate can happen through consumption of contaminated food or water. Workers involved in the application or manufacture of dimethoate are typically exposed through contact with skin, or through inhalation of aerosols and dust. [3]

Acute exposure in humans

In mammals, dimethoate has an LD50 of 150 mg/kg bodyweight in mice and 400 mg/kg bodyweight in rats. [3] Acute exposure through oral, dermal, or inhalation routes can cause symptoms such as diarrhea, nausea, sweating, blurred vision, difficulty breathing, and slowed heartbeat. Relapse situations where the patient appears to have stabilized before getting worse have been associated with higher exposure doses. Respiratory ailments, cholinesterase inhibitor exposure, impaired cholinesterase production, or liver malfunction can play a role in potentiating toxicity. [5]

Chronic exposure in humans

Chronic exposure to dimethoate can result in symptoms such as disorientation, irritability, impaired memory and concentration, nightmare, and speech difficulties. Chronic exposure as also been associated with nausea, loss of appetite, and malaise. Under normal conditions the chances of teratogenic, mutagenic, or carcinogenic effects from chronic exposure are low. [5]

Fruit fly control efforts

The Queensland fruit fly, or Bactrocera tryoni , is a tephritid fly species that has caused more than $28.5 million a year in damage to Australian fruit crops. In order to combat infestation, farmers treated crops with dimethoate and fenthion. [7] In 2011 the Australian Pesticides and Veterinary Medicines Authority (APVMA) banned the use of dimethoate containing products on food producing plants in home gardens, as well as on a variety of fruits, berries, cucurbits, and vegetables. [8] In September 2023, due to concerns that dimethoate and omethoate levels were exceeding acceptable maximum residue limits on avocados and mangoes, the APVMA issued a 12-month suspension notice on the use of dimethoate containing compounds as a post-harvest dip to control fruit flies on certain tropical fruits, including avocados and mangoes. [9] [10]

Trade names

Dimethoate is sold under various trade names, including Cygon, De-fend, Rogor, Rogodan, Rogodial, Roxion, Dimetate, Devigon, Dicap, Dimet, and B-58. [6] [11] [12] [13]

Poisoning incidents

In late October 2020 a Bulgarian farmer, a previous jackpot winner of the national 'toto' lottery drank a glass of the Russian B-58 brand, as of early November 2020 he is hospitalised in a comatose condition, he has a history of psychiatric issues but it is currently unknown whether the incident was accidental or intentional. [14]

Related Research Articles

<span class="mw-page-title-main">Insecticide</span> Pesticide used against insects

Insecticides are pesticides used to kill insects. They include ovicides and larvicides used against insect eggs and larvae, respectively. Acaricides, which kill mites and ticks, are not strictly insecticides, but are usually classified together with insecticides. The major use of Insecticides is agriculture, but they are also used in home and garden, industrial buildings, vector control and control of insect parasites of animals and humans. Insecticides are claimed to be a major factor behind the increase in the 20th-century's agricultural productivity. Nearly all insecticides have the potential to significantly alter ecosystems; many are toxic to humans and/or animals; some become concentrated as they spread along the food chain.

<span class="mw-page-title-main">Malathion</span> Chemical compound

Malathion is an organophosphate insecticide which acts as an acetylcholinesterase inhibitor. In the USSR, it was known as carbophos, in New Zealand and Australia as maldison and in South Africa as mercaptothion.

<span class="mw-page-title-main">Chlorfenvinphos</span> Chemical compound

Chlorfenvinphos is an organophosphorus compound that was widely used as an insecticide and an acaricide. The molecule itself can be described as an enol ester derived from dichloroacetophenone and diethylphosphonic acid. Chlorfenvinphos has been included in many products since its first use in 1963. However, because of its toxic effect as a cholinesterase inhibitor it has been banned in several countries, including the United States and the European Union. Its use in the United States was discontinued in 1991.

<span class="mw-page-title-main">Organophosphate</span> Organic compounds with the structure O=P(OR)3

In organic chemistry, organophosphates (also known as phosphate esters, phosphorates(V) or OPEs) are a class of organophosphorus compounds with the general structure O=P(OR)3, a central phosphate molecule with alkyl or aromatic substituents. They can be considered as esters of phosphoric acid. Organophosphates are best known for their use as pesticides.

Demeton-S-methyl is an organic compound with the molecular formula C6H15O3PS2. It was used as an organothiophosphate acaricide and organothiophosphate insecticide. It is flammable. With prolonged storage, Demeton-S-methyl becomes more toxic due to formation of a sulfonium derivative which has greater affinity to the human form of the acetylcholinesterase enzyme, and this may present a hazard in agricultural use.

<span class="mw-page-title-main">Aldicarb</span> Chemical compound (insecticide)

Aldicarb is a carbamate insecticide which is the active substance in the pesticide Temik. It is effective against thrips, aphids, spider mites, lygus, fleahoppers, and leafminers, but is primarily used as a nematicide. Aldicarb is a cholinesterase inhibitor which prevents the breakdown of acetylcholine in the synapse. Aldicarb is considered "extremely hazardous" by the EPA and World Health Organization and has been banned in more than 100 countries. In case of severe poisoning, the victim dies of respiratory failure.

<span class="mw-page-title-main">Fenthion</span> Chemical compound

Fenthion is an organothiophosphate insecticide, avicide, and acaricide. Like most other organophosphates, its mode of action is via cholinesterase inhibition. Due to its relatively low toxicity towards humans and mammals, fenthion is listed as moderately toxic compound in U.S. Environmental Protection Agency and World Health Organization toxicity class.

<span class="mw-page-title-main">Dichlorvos</span> Insect killing chemical, organophosphate

Dichlorvos is an organophosphate widely used as an insecticide to control household pests, in public health, and protecting stored products from insects. The compound has been commercially available since 1961. It has become controversial because of its prevalence in urban waterways and the fact that its toxicity extends well beyond insects. Since 1988, dichlorvos cannot be used as a plant protection product in the EU.

<span class="mw-page-title-main">Phosmet</span> Organophosphate non-systemic insecticide

Phosmet is a phthalimide-derived, non-systemic, organophosphate insecticide used on plants and animals. It is mainly used on apple trees for control of codling moth, though it is also used on a wide range of fruit crops, ornamentals, and vines for the control of aphids, suckers, mites, and fruit flies.

<span class="mw-page-title-main">Organophosphate poisoning</span> Toxic effect of pesticides

Organophosphate poisoning is poisoning due to organophosphates (OPs). Organophosphates are used as insecticides, medications, and nerve agents. Symptoms include increased saliva and tear production, diarrhea, vomiting, small pupils, sweating, muscle tremors, and confusion. While onset of symptoms is often within minutes to hours, some symptoms can take weeks to appear. Symptoms can last for days to weeks.

<span class="mw-page-title-main">Acephate</span> Chemical compound

Acephate is an organophosphate foliar and soil insecticide of moderate persistence with residual systemic activity of about 10–15 days at the recommended use rate. It is used primarily for control of aphids, including resistant species, in vegetables and in horticulture. It also controls leaf miners, caterpillars, sawflies, thrips, and spider mites in the previously stated crops as well as turf, and forestry. By direct application to mounds, it is effective in destroying imported fire ants.

<span class="mw-page-title-main">Clothianidin</span> Chemical compound

Clothianidin is an insecticide developed by Takeda Chemical Industries and Bayer AG. Similar to thiamethoxam and imidacloprid, it is a neonicotinoid. Neonicotinoids are a class of insecticides that are chemically similar to nicotine, which has been used as a pesticide since the late 1700s. Clothianidin and other neonicotinoids act on the central nervous system of insects as an agonist of nAChR, the same receptor as acetylcholine, the neurotransmitter that stimulates and activating post-synaptic acetylcholine receptors but not inhibiting AChE. Clothianidin and other neonicotinoids were developed to last longer than nicotine, which is more toxic and which breaks down too quickly in the environment.

<span class="mw-page-title-main">Methiocarb</span> Chemical compound

Methiocarb is a carbamate pesticide which is used as an insecticide, bird repellent, acaricide and molluscicide since the 1960s. Methiocarb has contact and stomach action on mites and neurotoxic effects on molluscs. Seeds treated with methiocarb also affect birds. Other names for methiocarb are mesurol and mercaptodimethur.

<span class="mw-page-title-main">Demeton</span> Chemical compound

Demeton, sold as an amber oily liquid with a sulphur like odour under the name Systox, is an organophosphate derivative causing irritability and shortness of breath to individuals repeatedly exposed. It was used as a phosphorothioate insecticide and acaricide and has the chemical formula C8H19O3PS2. Although it was previously used as an insecticide, it is now largely obsolete due to its relatively high toxicity to humans. Demeton consists of two components, demeton-S and demeton-O in a ratio of approximately 2:1 respectively. The chemical structure of demeton is closely related to military nerve agents such as VX and a derivative with one of the ethoxy groups replaced by methyl was investigated by both the US and Soviet chemical-weapons programs under the names V-sub x and GD-7.

<span class="mw-page-title-main">Health effects of pesticides</span> How pesticides affect human health

Health effects of pesticides may be acute or delayed in those who are exposed. Acute effects can include pesticide poisoning, which may be a medical emergency. Strong evidence exists for other, long-term negative health outcomes from pesticide exposure including birth defects, fetal death, neurodevelopmental disorder, cancer, and neurologic illness including Parkinson's disease. Toxicity of pesticides depend on the type of chemical, route of exposure, dosage, and timing of exposure.

<span class="mw-page-title-main">Carbophenothion</span> Chemical compound

Carbophenothion also known as Stauffer R 1303 as for the manufacturer, Stauffer Chemical, is an organophosphorus chemical compound. It was used as a pesticide for citrus fruits under the name of Trithion. Carbophenothion was used as an insecticide and acaricide. Although not used anymore it is still a restricted use pesticide in the United States. The chemical is identified in the US as an extremely hazardous substance according to the Emergency Planning and Community Right-to-Know Act.

<span class="mw-page-title-main">Tetraethyl pyrophosphate</span> Chemical compound

Tetraethyl pyrophosphate, abbreviated TEPP, is an organophosphate compound with the formula [(C2H5O)2P(O)]2O. It is the tetraethyl derivative of pyrophosphate (P2O74-). It is a colorless oil that solidifies near room temperature. It is used as an insecticide. The compound hydrolyzes rapidly.

<span class="mw-page-title-main">Terbufos</span> Chemical compound

Terbufos is a chemical compound used in insecticides and nematicides. It is part of the chemical family of organophosphates. It is a clear, colourless to pale yellow or reddish-brown liquid and sold commercially as granulate.

<span class="mw-page-title-main">Triazofos</span> Chemical compound

Triazofos is a chemical compound used in acaricides, insecticides, and nematicides.

<span class="mw-page-title-main">Cadusafos</span> Thiosulfate insecticide against nematodes

Cadusafos is a chemical insecticide and nematicide often used against parasitic nematode populations. The compound acts as a acetylcholinesterase inhibitor. It belongs the chemical class of synthetic organic thiophosphates and it is a volatile and persistent clear liquid. It is used on food crops such as tomatoes, bananas and chickpeas. It is currently not approved by the European Commission for use in the EU. Exposure can occur through inhalation, ingestion or contact with the skin. The compound is highly toxic to nematodes, earthworms and birds but poses no carcinogenic risk to humans.

References

  1. 1 2 3 Sigma-Aldrich Co., Dimethoate.
  2. Dauterman WC, Viado GB, Casida JE, O'brien RD (1960). "Insecticide Residues, Persistence of Dimethoate and Metabolites Following Foliar Application to Plants". Journal of Agricultural and Food Chemistry. 8 (2): 115–9. doi:10.1021/jf60108a013.
  3. 1 2 3 4 "Dimethoate Biomonitoring Summary". U.S. Centers for Disease Control and Prevention. 2021-09-09. Retrieved 2023-10-29.
  4. 1 2 3 "Revised Interim Reregistration Eligibility Decisions for Dimethoate" (PDF). US Environmental Protection Agency Office of Pesticide Programs. Environmental Protection Agency. October 2008. EPA-HQ-OPP-2005-0084.
  5. 1 2 3 4 Mirajkar N, Pope CN (January 2005). "Dimethoate". In Wexler P (ed.). Encyclopedia of Toxicology (Second ed.). New York: Elsevier. pp. 47–49. doi:10.1016/b0-12-369400-0/00330-6. ISBN   978-0-12-369400-3.
  6. 1 2 3 4 Van Scoy A, Pennell A, Zhang X (2016). "Environmental Fate and Toxicology of Dimethoate". In de Voogt WP (ed.). Reviews of Environmental Contamination and Toxicology Volume 237. Vol. 237. Cham: Springer International Publishing. pp. 53–70. doi:10.1007/978-3-319-23573-8_3. ISBN   978-3-319-23573-8. PMID   26613988.
  7. Lloyd AC, Hamacek EL, Kopittke RA, Peek T, Wyatt PM, Neale CJ, et al. (May 2010). "Area-wide management of fruit flies (Diptera: Tephritidae) in the Central Burnett district of Queensland, Australia". Crop Protection. 29 (5): 462–469. doi:10.1016/j.cropro.2009.11.003. ISSN   0261-2194.
  8. "Dimethoate chemical review". Australian Pesticides and Veterinary Medicines Authority. Retrieved 2023-10-29.
  9. "Notice of suspension – certain dimethoate products and labels". Gazette. Australian Pesticides and Veterinary Medicines Authority. 19 September 2023. Retrieved 2023-10-29.
  10. Morris N (2023-09-22). "This neurotoxin is now suspended from use on mangoes and avocados after harvest, so why not oranges?". ABC News. Retrieved 2023-10-29.
  11. Padmasheela NC, Delvi MR (October 2004). "Effect of Dimethoate (Rogor 30% EC) on the brain neurosecretory cells of third instar grubs of Oryctes rhinoceros L. (Coleoptera : Scarabaeidae)". Journal of Environmental Biology. 25 (4): 451–455. PMID   15907075.
  12. "Rogor". Ravensdown.
  13. "Insecticides_acaricides B-58 | Detailed description, photo , growing, buy". SemenaOpt.com.
  14. Maskruchka A (12 February 2020). "Остава тежко състоянието на тотомилионера, натровил се с Б-58" [The condition of the milldionaire who poisoned himself with B-58 remains serious]. 24 Chasa (in Bulgarian).