Carbofuran

Carbofuran
IUPAC name	2,2-dimethyl-2,3-dihydro-1-benzofuran-7-yl methylcarbamate
Other names	Carbofuran, Furadan, Curater
Identifiers
CAS number	1563-66-2 Y
PubChem	2566
SMILES	O=C(Oc2cccc1c2OC(C1)(C)C)NC
InChI	1/C12H15NO3/c1-12(2)7-8-5-4-6-9(10(8)16-12)15-11(14)13-3/h4-6H,7H2,1-3H3,(H,13,14)
InChI key	DUEPRVBVGDRKAG-UHFFFAOYAB
ChemSpider ID	2468
Properties
Molecular formula	C12H15NO3
Molar mass	221.25 g mol−1
Density	1.18 g/cm3
Melting point	151°C[1]
Y (what is this?)  (verify) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Carbofuran is one of the most toxic carbamate pesticides. It is marketed under the trade names Furadan, by FMC Corporation and Curater, among several others. It is used to control insects in a wide variety of field crops, including potatoes, corn and soybeans. It is a systemic insecticide, which means that the plant absorbs it through the roots, and from here the plant distributes it throughout its organs (mainly vessels, stems and leaves; not the fruits)^{[citation needed]}, where insecticidal concentrations are attained. Carbofuran also has contact activity against pests.

Carbofuran usage has increased in recent years because it is one of the few insecticides effective on soybean aphids, which have expanded their range since 2002 to include most soybean-growing regions of the U.S. The main global producer is the FMC Corporation.

The technical or chemical name of carbofuran is 2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate and its CAS number is 1563-66-2 and it is manufactured by reaction of methyl isocyanate with 2,3-dihydro-2,2-dimethyl-7-hydroxybenzofuran.

Bans

Kenya is considering banning Carbofuran, but it^[2] is legal to buy over-the-counter in Kenya.^[3]

In 2008, the United States Environmental Protection Agency (EPA) announced that it intends to ban carbofuran.^[4] In December of that year, FMC Corp., the sole US manufacturer of carbofuran, announced that it had voluntarily requested that the United States Environmental Protection Agency cancel all but 6 of previously-allowed uses of that chemical as a pesticide. With this change, carbofuran usage in the US would be allowed only on corn, potatoes, pumpkins, sunflowers, pine seedlings and spinach grown for seed.^[5] However, in May 2009 EPA cancelled all food tolerances, an action which amounts to a de facto ban on its use on all crops grown for human consumption.^[6]

Toxicity to vertebrates

Oral LD50: Rats 8–14 mg/kg, Dogs 19 mg/kg.

Carbofuran is also known to be highly toxic to birds. In its granular form, a single grain will kill a bird. Birds often eat numerous grains of the pesticide, mistaking them for seeds, and then die shortly thereafter. Before the granular form was banned by U.S. Environmental Protection Agency‎ in 1991,^[7] granular carbofuran was blamed for millions of bird deaths per year. The liquid version of the pesticide is less hazardous to birds since they are not as likely to ingest it directly, but it is still very hazardous. The EPA announced on July 25, 2008 it intends to ban all forms in the US.^[8] The ban requires that no residue be present on domestic or imported foods. ^[9]

Carbofuran has been illegally used to intentionally poison coyotes and other wildlife in the US and Canada. Secondary fatal poisoning of domestic and wild animals has been documented,^[10][11] specifically, raptors (bald eagles and golden eagles), domestic dogs, raccoons, vultures and other scavengers.

In Kenya farmers are using carbofuran to kill lions and other predators.^[3][12]

Toxicity to humans

Carbofuran has one of the highest acute toxicities to humans of any insecticide widely used on field crops (only aldicarb and parathion are more toxic). A quarter teaspoon ( 1 mL) can be fatal. Most carbofuran is applied by commercial applicators using closed systems with engineered controls so there is no exposure to it in preparation. Since its toxic effects are due to its activity as a cholinesterase inhibitor it is considered a neurotoxic pesticide.

See also

• Dutch standards

References

External links

• FuradanFacts.com