ジチオりん酸O,O-ジメチルS-[(5-メトキシ-2-オキソ-1,3,4-チアジアゾール-3(2H)-イル)メチル] 化学特性,用途語,生産方法
外観
白色, 結晶～結晶性粉末
溶解性
水に難溶。殆どの有機溶媒に可溶。水200mg/l(25℃)。エタノール150, アセトン670, トルエン720, ヘキサン11, n-オクタノール14(全てg/l 20℃)。エタノール及びアセトンに溶けやすく、水に極めて溶けにくい。
農薬用途
殺虫剤
説明
Methidation is used as an insecticide. Cross-sensitivity
was described to dichlorvos.
化学的特性
Methidathion is a colorless crystalline pesticide at room temperature. It is sparingly soluble in water, but very soluble in octanol, ethanol, xylene, acetone, and cyclohexane. Methidathion is a non-systemic organophosphorous insecticide and acaricide with stomach and contact action. It is used to control a variety of insects and mites on crops and fruit plants. Methidathion is highly toxic to animals and humans. The US EPA grouped methidathion as a class I toxic substance and as an RUP.
使用
Methidathion is an organophosphate insecticide and was examined for human health and toxicological concerns.
一般的な説明
Methidathion is a colourless crystalline pesticide at room temperature. It is sparingly soluble in water but very soluble in octanol, ethanol, xylene, acetone, and cyclohexane.
空気と水の反応
Stable in neutral or weak acid solution. Hydrolyzed by alkali. [EPA, 1998].
反応プロフィール
Organophosphates, such as Methidathion, are susceptible to formation of highly toxic and flammable phosphine gas in the presence of strong reducing agents such as hydrides. Partial oxidation by oxidizing agents may result in the release of toxic phosphorus oxides.
危険性
Toxic by ingestion, a cholinesterase
inhibitor.
健康ハザード
Methidathion is poisonous to humans. Its toxic effects are by action on the nervous system. Human volunteers ingesting 0.11 mg/kg/day for 6 weeks had no clinical effects.
火災危険
(Non-Specific -- Organophosphorus Pesticide, n.o.s.) Container may explode in heat of fire. Fire and runoff from fire control water may produce irritating or poisonous gases. Stable in neutral or weak acid solution. Hydrolyzed by alkali.
农业用途
Insecticide: A U.S. EPA restricted Use Pesticide (RUP). Not approved for use in EU countries
. There are no residential
uses for methidathion. Methidathion is a non-systemic organophosphate insecticide and acaricide with stomach and
contact action. The compound is used to control a variety
of insects and mites in many crops such as nuts, artichokes,
olives, cotton, fruits, vegetables, tobacco, alfalfa, and sunflowers, and also in greenhouses and on rose cultures. It is
especially useful against scale insects.
製品名
CIBA-GEIGY® GS 13005®;
COBRACIDE®; FISONS NC® 2964; GEIGY® 13005; GS-13005®; SOMONIC®; SOMONIL®; SURPRACIDE®;
SUPRATHION®; ULTRACID®; ULTRACIDE®
接触アレルゲン
Methidation is an organophosphorus compound used as an insecticide. Cross-sensitivity was described to Dichlorvos.
安全性プロファイル
Poison by ingestion and
skin contact. Moderately toxic by inhalation.
Human mutation data reported. Human
systemic effects: coma, lachrymation, miosis.
A severe eye irritant. An insecticide. When
heated to decomposition it emits very toxic
fumes of NOx, POx, and SOx
発がん性
In a chronic toxicity/carcinogenicity study, rats were fed
diets with 0, 4, 40, or 100 ppm methidathion (equivalent to 0,
0.16, 1.72, or 4.91 mg/kg/day (males) and 0, 0.22, 2.20, or
6.93 mg/kg/day (females)) for 2 years, and there was no
evidence of carcinogenicity in either males or females .
Body weight decreases occurred in both sexes at the highest
dose throughout the study.
環境運命予測
Photolytic. When methidathion in an aqueous buffer solution (25°C and pH 7.0) was
exposed to filtered UV light (l >290 nm) for 24 hours, 17% decomposed to 5-methoxy-
3H-1,3,4-thiadiazol-2-one. At 50°C, 56% was degraded after 24 hours. Degradation
occurred via hydrolysis of the thiol bond of the phosphorodithioic ester. Under acidic and
alkaline conditions, hydrolytic cleavage occurred at the C-S and P-S bonds, respectively
(Burkhard and Guth, 1979). Smith et al. (1978) demonstrated that methidathion degraded
to methidathion oxon at a faster rate in six air-dried soils than in moist soils. Half-lives
for methidathion in the air-dried soils ranged from 19 to 110 days. In addition, methidathion
degraded faster in an air-dried soil exposed to ozone (half-lives 2.5 to 7.0 days).
Chemical/Physical. Emits toxic fumes of phosphorus, nitrogen and sulfur oxides when
heated to decomposition (Sax and Lewis, 1987). Methidathion oxon was also found in
fogwater collected near Parlier, CA (Glotfelty et al., 1990). It was suggested
代謝経路
The main route of methidathion metabolism in animals and plants is via
hydrolysis or oxidation (or hydrolysis of the oxon) to yield the 3-
thiomethyl-5-methoxy-1,3,4-thiadiazoldee rivative. This may either lose
methanethiol to yield the methoxy-1,3,4thiadiazolinone or be conjugated
as the cysteine derivative via a route involving desmethylmethidathion
(in plants). In plants and mammals an additional route involves the
methylation of the thiomethyl methoxy-1,3,4-thiadiazolinone derivative
by S-adenosylmethionine followed by oxidation to the corresponding
sulfoxide and sulfone which are excreted in the urine in mammals.
Another route of detoxification in insects, plants and mammals is via
demethylation of the 5-methoxy group of the 1,3,4-thiadiazolinone ring
to form a metabolite which may be conjugated in plants. As is common
with many phosphorothioates, the active acetylcholinesterase inhibitor,
methidaoxon, is usually detected in metabolism studies but at very low
concentration due to its rapid rate of hydrolysis.
代謝
The principal degradation route is similar
both in animals and plants, that is, cleavage of the P?S
bond via oxidative desulfuration (activation) to the oxon
followed by hydrolysis to O,O-dimethyl hydrogen phosphorothioate
and the 3-thiomethyl-5-methoxythiadiazole
derivative, which is further degraded or conjugated.
Methidathion is rapidly degraded in soil; DT
50 in soil
is 3–18 d.
輸送方法
Color code—Blue: Health Hazard/Poison: Store in
a secure poison location. Prior to working with this chemical, personnel should be trained on its proper handling and
storage. Store in tightly closed containers in a cool, wellventilated area
廃棄物の処理
Treat with strong alkali, mix
with soil and bury in the case of small quantities.
For large quantities, use incineration with effluent gas
scrubbing
予防処置
Occupational workers should be very careful during use and chemical management of methidathion. As this chemical substance is a highly toxic pesticide, it has been grouped by the US EPA as toxicity class I. The containers and labels of the products should bear the signal word DANGER. Methidathion is an RUP, except for use in nurseries, and on saffl ower and sunfl owers.
ジチオりん酸O,O-ジメチルS-[(5-メトキシ-2-オキソ-1,3,4-チアジアゾール-3(2H)-イル)メチル] 上流と下流の製品情報
原材料
準備製品