Names | |
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IUPAC name Dimethyl-1,2-dibromo-2,2-dichlorethyl phosphate | |
Other names Dibrom, 1,2-Dibromo-2,2-dichloroethyl dimethyl phosphate | |
Identifiers | |
3D model (JSmol) | |
2049930 | |
ChEBI | |
ChEMBL | |
ChemSpider | |
ECHA InfoCard | 100.005.545 |
EC Number |
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KEGG | |
PubChem CID | |
RTECS number |
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UNII | |
UN number | 3018 2783 |
CompTox Dashboard (EPA) | |
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Properties | |
C4H7O4PBr2Cl2 [1] | |
Molar mass | 380.8 g/mol [1] |
Appearance | Colorless to white solid or straw-colored liquid [1] |
Density | 1.96 g/mL (25°C) [1] |
Melting point | 27 °C; 80 °F; 300 K [1] |
Boiling point | decomposes [1] |
Vapor pressure | 0.0002 mmHg (20°C) [1] |
Hazards | |
GHS labelling: | |
Warning | |
H302, H312, H315, H319, H400 | |
P264, P270, P273, P280, P301+P312, P302+P352, P305+P351+P338, P312, P321, P322, P330, P332+P313, P337+P313, P362, P363, P391, P501 | |
Flash point | noncombustible [1] |
Lethal dose or concentration (LD, LC): | |
LD50 (median dose) | 156 mg/kg (inhaled, mouse) 222 mg/kg (oral, mouse) 160 mg/kg (oral, rat) 430 mg/kg (oral, mammal) 250 mg/kg (oral, rat) 330 mg/kg (oral, mouse) [2] |
NIOSH (US health exposure limits): | |
PEL (Permissible) | TWA 3 mg/m3 [skin] [1] |
REL (Recommended) | TWA 3 mg/m3 [skin] [1] |
IDLH (Immediate danger) | 200 mg/m3 [1] |
Safety data sheet (SDS) | MSDS |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Naled (Dibrom) is an organophosphate insecticide. [3] [4] Its chemical name is dimethyl 1,2-dibromo-2,2-dichloroethylphosphate.
Naled is stable in anhydrous condition and must be stored away from light. It must also be stored under normal pressure and temperatures. It degrades in the presence of water and alkali, and produces toxic chloride fumes if exposed to acids or acidic fumes. Contact with metals, reducing agents, or sulfhydryls cause naled to release bromide and revert to dichlorvos. [4]
Naled is used primarily to control adult mosquitos. It is also registered to control black flies, and leaf eating insects on a variety of fruits, vegetables, and nuts. Approximately 70% of naled in USA is used in mosquito control, and approximately 30% in agriculture. [5] Naled has also been used in veterinary medicine to kill parasitic worms in dogs.
It has been used extensively within the United States since the 1950s. Naled was used in New Orleans after Hurricane Katrina, in North Carolina after Hurricane Florence (2018), [6] and has been used historically in Puerto Rico to control dengue. [7] [8]
The Environmental Protection Agency has determined that exposure levels from eating crops treated with Naled are below the level of concern. [5] With higher exposures, however, naled can cause cholinesterase inhibition in humans, which in turn can overstimulate the nervous system causing nausea, dizziness, confusion, and at very high exposures, respiratory paralysis and death. [5] It has the UN hazard classification of 6.1 (inhalation hazard) and is prohibited for use as an insecticide within the EU. [9] [10]
Naled may cross the placenta if it is in the bloodstream of a mammal. [4] Repeated exposures may also cause future behavioral problems, [11] [12] as well as issues with neurodevelopment, growth, and respiratory health in offspring. [12] Chronic exposure to dichlorvos, a metabolite of naled, [4] [13] [12] has also been linked to neurological issues, such as Parkinson's disease and nigrostriatal dopaminergic degeneration. [14] Persons who work closely with naled or other organophosphate pesticides should undergo regular testing of their cholinesterase levels. [4]
EPA classifies naled as Group E or non-carcinogenic for humans. [7] Neither naled nor its metabolite, dichlorvos, build up in breast milk or breast tissue. [7]
In a 2017 general-population study of the chemical, University of Michigan researchers found that children in China who had the highest prenatal exposure to naled had, at age 9 months, 3% to 4% lower scores on tests of their fine motor skills, compared with those with the lowest exposure. [15]
Naled is considered highly toxic to bees, [7] [16] as well as being moderately to highly toxic to birds and toxic to most aquatic life. Naled is also toxic to butterflies at amounts typically used to control mosquitoes. [17] [18] The mule deer is among those most resistant to its effects. [4] [13] Naled is banned in the European Union because of concerns about the toxicity.
Aerial spraying of naled has been recommended by the Centers for Disease Control and Prevention and United States Environmental Protection Agency [19] [20] for the prevention of the spread of the Zika virus in the United States. [7] Experts at both the CDC and EPA, as well as independent universities, have argued that naled is safer than other chemicals and should not cause significant health issues due to the low level of exposure. [7] [19]
The federal government had considered using the chemical in Puerto Rico to stop the spread of Zika, but decided against it due to the potential danger to pregnant women. [21] Its proposed use against Zika led to protests in Puerto Rico. [11] [20]
Miami is using specialized trucks to spray naled and Bacillus thuringiensis israelensis (BTI). [7] [11] Governor Rick Scott said that the CDC recommended using helicopters to spray the insecticides, but some people in Miami [20] and Miami Beach are opposed to aerial spraying. [11]
Spraying of naled in Dorchester County, South Carolina purportedly led to the deaths of 3 million honeybees [16] [22] and increased criticism by beekeepers. [19] Beekeepers in the county complained that they had not been notified of spraying before it happened. [16] Juanita Stanley, a beekeeper and co-owner of Flowerton Bee Farm and Supply, told CNN, "Now, I'm going to have to destroy my hives, the honey, all my equipment. It's all contaminated." [22] Jennifer Holmes, vice-president of the Florida State Beekeepers Association, compared the loss of bees to other forms of agriculture, saying, "If there was a regulation that allowed some spraying that would kill half of your livestock overnight, how would you recover?" She went on to say that "we understand the serious threat of possible disease, but we also have to maintain our agricultural livelihood.” [19]
Dichlorodiphenyltrichloroethane, commonly known as DDT, is a colorless, tasteless, and almost odorless crystalline chemical compound, an organochloride. Originally developed as an insecticide, it became infamous for its environmental impacts. DDT was first synthesized in 1874 by the Austrian chemist Othmar Zeidler. DDT's insecticidal action was discovered by the Swiss chemist Paul Hermann Müller in 1939. DDT was used in the second half of World War II to limit the spread of the insect-borne diseases malaria and typhus among civilians and troops. Müller was awarded the Nobel Prize in Physiology or Medicine in 1948 "for his discovery of the high efficiency of DDT as a contact poison against several arthropods". The WHO's anti-malaria campaign of the 1950s and 1960s relied heavily on DDT and the results were promising, though there was a resurgence in developing countries afterwards.
Pesticides are substances that are meant to control pests. This includes herbicide, insecticide, nematicide, molluscicide, piscicide, avicide, rodenticide, bactericide, insect repellent, animal repellent, microbicide, fungicide, and lampricide. The most common of these are herbicides, which account for approximately 50% of all pesticide use globally. Most pesticides are intended to serve as plant protection products, which in general, protect plants from weeds, fungi, or insects. In general, a pesticide is a chemical or biological agent that deters, incapacitates, kills, or otherwise discourages pests. Target pests can include insects, plant pathogens, weeds, molluscs, birds, mammals, fish, nematodes (roundworms), and microbes that destroy property, cause nuisance, or spread disease, or are disease vectors. Along with these benefits, pesticides also have drawbacks, such as potential toxicity to humans and other species.
Insecticides are pesticides used to kill insects. They include ovicides and larvicides used against insect eggs and larvae, respectively. Insecticides are used in agriculture, medicine, industry and by consumers. 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.
Chlordane, or chlordan, is an organochlorine compound that was used as a pesticide. It is a white solid. In the United States, chlordane was used for termite-treatment of approximately 30 million homes until it was banned in 1988. Chlordane was banned 10 years earlier for food crops like corn and citrus, and on lawns and domestic gardens.
Pyrethrum was a genus of several Old World plants now classified as Chrysanthemum or Tanacetum which are cultivated as ornamentals for their showy flower heads. Pyrethrum continues to be used as a common name for plants formerly included in the genus Pyrethrum. Pyrethrum is also the name of a natural insecticide made from the dried flower heads of Chrysanthemum cinerariifolium and Chrysanthemum coccineum. The insecticidal compounds present in these species are pyrethrins.
N,N-Diethyl-meta-toluamide, also called diethyltoluamide or DEET, is the oldest, most effective and most common active ingredient in commercial insect repellents. It is a slightly yellow oil intended to be applied to the skin or to clothing and provides protection against mosquitoes, flies, ticks, fleas, chiggers, leeches, and many other biting insects.
Parathion, also called parathion-ethyl or diethyl parathion and locally known as "Folidol", is an organophosphate insecticide and acaricide. It was originally developed by IG Farben in the 1940s. It is highly toxic to non-target organisms, including humans, so its use has been banned or restricted in most countries. The basic structure is shared by parathion methyl.
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.
In organic chemistry, organophosphates 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.
Pesticides vary in their effects on bees. Contact pesticides are usually sprayed on plants and can kill bees when they crawl over sprayed surfaces of plants or other areas around it. Systemic pesticides, on the other hand, are usually incorporated into the soil or onto seeds and move up into the stem, leaves, nectar, and pollen of plants.
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.
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.
Methoxychlor is a synthetic organochloride insecticide, now obsolete. Tradenames for methoxychlor include Chemform, Maralate, Methoxo, Methoxcide, Metox, and Moxie.
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 and 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.
Pyriproxyfen is a pesticide which is found to be effective against a variety of insects. It was introduced to the US in 1996, to protect cotton crops against whitefly. It has also been found useful for protecting other crops. It is also used as a prevention for flea control on household pets, for killing indoor and outdoor ants and roaches. Methods of application include aerosols, bait, carpet powders, foggers, shampoos and pet collars.
Phenothrin, also called sumithrin and d-phenothrin, is a synthetic pyrethroid that kills adult fleas and ticks. It has also been used to kill head lice in humans. d-Phenothrin is used as a component of aerosol insecticides for domestic use. It is often used with methoprene, an insect growth regulator that interrupts the insect's biological lifecycle by killing the eggs.
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.
Propoxur (Baygon) is a carbamate non-systemic insecticide, produced from catechol, and was introduced in 1959. It has a fast knockdown and long residual effect, and is used against turf, forestry, and household pests and fleas. It is also used in pest control for domestic animals, Anopheles mosquitoes, ants, gypsy moths, and other agricultural pests. It can also be used as a molluscicide.
This is an index of articles relating to pesticides.
Sulfoxaflor, also marketed as Isoclast, is a systemic insecticide that acts as an insect neurotoxin. A pyridine and a trifluoromethyl compound, it is a member of a class of chemicals called sulfoximines, which act on the central nervous system of insects.
Naled degrades fairly rapidly with half-lifes of <=8 hours in soils and <=25 hours in aqueous solutions. Dichlorvos (DDVP), a metabolite of naled, is also rapidly degraded in soil with half-lifes of 2.3 - 8.0 hours. Naled exhibits low to intermediate mobility in soils, whereas dichlorvos is intermediately mobile to mobile.