ALDICARB

Описание

Aldicarb is a carbamate pesticide that reversibly inhibits acetylcholinesterase. It is the active ingredient in mixtures used to control insect, mite, and nematode pests in agriculture. Aldicarb has a high acute mammalian toxicity (LD₅₀ = 0.3-0.5 mg/kg) following oral or parenteral administration. Aside from its use as a pesticide, aldicarb has applications as an acetylcholinesterase inhibitor for research purposes.

Химические свойства

Aldicarb is a noncombustible, white crystalline solid with a slight sulfurous odor.It is not compatible with alkaline materials and is non-corrosive to metals and plastics. It is sparingly soluble in water, but soluble in acetone, xylene, ethyl ether, toluene, and other organic solvents. Aldicarb has been classifi ed as an RUP and hence should only be used by trained and certifi ed workers. Aldicarb is used to control mites, nematodes, and aphids and is applied directly to the soil. It is used widely on cotton, peanut, and soybean crops. In the mid-1980s, there were highly publicized incidents in which misapplication of aldicarb contaminated cucumbers and watermelons and led to adverse effects in people. Aldicarb is metabolized in the liver of mammals fi rst into aldicarb sulfoxide and later into aldicarb sulfone.

Использование

Aldicarb is a broad-spectrum, systemic carbamate insecticide used to control nema-todes in soil and a variety of insects and mites on citrus crops, dry beans, grain, sorghum, ornamentals, pecans, peanuts, potatoes, seed alfalfa, soybeans, sugar beets, sugarcane, sweet potatoes, and tobacco.

Определение

ChEBI: The oxime carbamate resulting from the addition of 2-methyl-2-(methylsulfanyl)propanaldoxime to methyl isocyanate. A member of the class of oxime carbamate insecticides, aldicarb is a mixture of E and Z isomers; it is not nown which isomer is more active.

Подготовка

Aldicarb is prepared by treating isobutene with nitrosyl chloride, treating the resulting dimeric adduct with sodium methyl sulfide, and converting the resulting oxime to the carbamate with methyl isocyanate. Warning: the dimeric isobutene nitrosochloride is unstable and decomposes explosively at 94 °C. The oxime and end product also decompose vigorously above 140 and 160 °C, respectively.

Общее описание

White crystals with a slightly sulfurous odor. Commercial formulations are granular Used as an insecticide, acaricide, and nematocide.

Реакции воздуха и воды

Slightly water soluble.

Профиль реактивности

ALDICARB is a carbamate ester. ALDICARB decomposes at temperatures greater than 212° F. ALDICARB is incompatible with highly alkaline substances. ALDICARB is rapidly converted by oxidizing agents.

Пожароопасность

When heated to decomposition, ALDICARB emits very toxic fumes of nitrogen oxides and sulfur oxides. Incompatible with highly alkaline substances. Unstable in alkali; poor stability at 122F.

Сельскохозяйственное использование

Insecticide, Nematicide, Acaricide: A U.S. EPA restricted Use Pesticide (RUP). Not approved for use in EU countries.

Торговое название

TEMIC®; TEMIK®; OMS 771®; TERNIC®; TEMIK 10 G®

Профиль безопасности

Deadly poison by ingestion, skin contact, subcutaneous, and possibly other routes. Human mutation data reported. Questionable carcinogen. A powerful systemic poison. In 1985 over 150 people in California exhibited toxic effects from eating watermelons contaminated with aldicarb. When heated to decomposition it emits very toxic fumes of NOx and SOx

Возможный контакт

Exposure to aldicarb and aldicarb sulfoxide and sulfone will occur mainly through the ingestion and contaminated drinking water derived from contaminated ground water as well as contaminated food.

Экологическая судьба

Aldicarb and its degradation products are generally very soluble in water and mobile in soil. Adsorption in soil is primarily to organic matter, so leaching is most exten- sive in sandy or sandy loam soils. Aldicarb is very persistent in groundwater, typi- cally degrading to nontoxic products with a half-life between a few weeks to as long as several years. The primary mode of degradation is chemical hydrolysis, with some microbial decay in shallow groundwater. In soils, the primary mode of degradation is oxidation by soil microorganisms and hydrolysis, depending on soil conditions.

Метаболический путь

In an aqueous buffer solution in the pH range 2.91 ? 5.51, the Cu(II) ion promotes the decomposition of aldicarb, forming the degradation products 2-methyl- 2-(methylthio)propionitrile and 2-methyl-2- (methylthio)propanal.

хранилище

Aldicarb should be kept stored in a dry, cool area, out of reach of children and animals, and away from food, feedstuffs, fertilizers, and seed.

Перевозки

UN2757 Carbamate pesticides, solid, toxic, Hazard Class: 6.1; Labels: 6.1-Poisonous materials

Несовместимости

Strong alkalis

Утилизация отходов

Do not discharge into drains or sewers. Dispose of waste material as hazardous waste using a licensed disposal contractor to an approved landfill. Consult with environmental regulatory agencies for guidance on acceptable disposal practices. Generators of waste containing this contaminant (≥100 kg/mo) must conform with EPA regulations governing storage, transportation, treatment, and waste disposal. Incineration with effluent gas scrubbing is recommended. In accordance with 40CFR165, follow recommendations for the disposal of pesticides and pesticide containers. In accordance with 40CFR165, follow recommendations for the disposal of pesticides and pesticide containers. Must be disposedproperly by following package label directions or by contacting your local or federal environmental control agency, or by contacting your regional EPA office.