Aldicarb

Aldicarb
IUPAC name 2-Methyl-2-(methylthio)propanal O-(N-methylcarbamoyl)oxime
Other names Temik
Identifiers
CAS number	116-06-3 Y
PubChem	9570071
ChemSpider	7844539 Y
UNII	8V071SH05P Y
KEGG	C11015 Y
ChEMBL	CHEMBL91732 Y
Jmol-3D images	Image 1
SMILES O=C(O\N=C\C(SC)(C)C)NC
InChI InChI=1S/C7H14N2O2S/c1-7(2,12-4)5-9-11-6(10)8-3/h5H,1-4H3,(H,8,10)/b9-5+ Y Key: QGLZXHRNAYXIBU-WEVVVXLNSA-N Y InChI=1/C7H14N2O2S/c1-7(2,12-4)5-9-11-6(10)8-3/h5H,1-4H3,(H,8,10)/b9-5+ Key: QGLZXHRNAYXIBU-WEVVVXLNBS
Properties
Molecular formula	C7H14N2O2S
Molar mass	190.26 g mol−1
Density	1.195 g/cm³
Melting point	100 °C, 373 K, 212 °F
Boiling point	Decomposes before boiling point
Y (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

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. In case of severe poisoning, the victim dies of respiratory failure.

Aldicarb is effective where resistance to organophosphate insecticides has developed, and is extremely important in potato production, where it is used for the control of soil-borne nematodes and some foliar pests. Its weakness is its high level of solubility, which restricts its use in certain areas where the water table is close to the surface.

Regulatory status

Aldicarb was approved by the USEPA for use by professional pesticide applicators on a variety of crops, including cotton, beans, and others. It is not approved for household use.

Aldicarb was one of the “dirty dozen” pesticides that the environmental group Pesticide Action Network North America targeted in 1985. EPA put a ban in place in 2010, requiring an end to distribution by 2017. Use on citrus and potatoes is banned beginning in 2012, with a complete ban in place by 2018. New labeling requirements and protections to ground water near cotton, soybean and peanut farms were implemented in 2010.

"Tres Pasitos", a mouse, rat, and roach killer that contains high concentrations of aldicarb, has been illegally imported into the United States from Mexico and other Latin American countries. The product is highly toxic to animals and people, and according to the EPA "should never be used in [the] home."

History

Aldicarb is manufactured by Bayer CropScience, but was formerly owned and produced by Union Carbide. Union Carbide's agricultural chemicals division was sold to Rhône-Poulenc. Later, Aventis Cropscience was formed from Hoechst AG and Rhone-Poulenc Agrochemical, which lasted until Bayer acquired it in 2002.

In 1985, nearly 1000 people in the western United States and Canada were poisoned by residue of aldicarb in watermelons.^{[citation needed]} Their symptoms included nausea, vomiting, blurred vision and muscle weakness. Although no one died, some of the victims were seriously ill, and two women later gave birth to stillborn babies. Later epidemiologic surveys of women who were pregnant at the time of the poisoning event failed to establish a causal relationship between the stillbirths and pesticide exposure.^{[citation needed]}

In November 2009, corn treated with Temik was placed in and around peanut fields in Eastland County, Texas, near the town of Cisco. The corn was eaten by feral hogs, deer, and other animals, prompting the Texas Parks and Wildlife Department to issue a hunting ban.

For humans, it is the most toxic insecticide used on field crops.

Toxicity in mammals

Aldicarb is a fast-acting cholinesterase inhibitor, causing rapid accumulation of acetylcholine at the synaptic cleft. It is widely used to study cholinergic neurotransmission in simple systems such as the nematode C. elegans.

Exposure to high amounts of aldicarb can cause weakness, blurred vision, headache, nausea, tearing, sweating, and tremors in humans. High doses can be fatal to humans because it can paralyze the respiratory system.

It has an LD₅₀ of 0.5-1.5 mg/kg when in liquid form and an LD₅₀ of 7 mg/kg when in solid form.^{[citation needed]} Because of its toxicity, its use is highly restricted in the EU/UK with maximum residue limits for apples and oranges being 0.02 mg/kg and this amount is only allowed because this is the limit of detection.^{[citation needed]}

In South Africa (where Aldicarb is popularly known as Two Step) it is widely used by burglars to poison dogs.