2540-82-1 Usage
Description
Formothion is a pale yellow liquid or crystalline mass that decomposes on distillation, with a melting point of 25-26°C and a vapor pressure of 0.113 mPa at 20°C. It is poorly soluble in water (2.6 g/L at 24°C) and miscible with most organic solvents, except aliphatic hydrocarbons. Formothion is an odorless, viscous oil or crystalline mass that is hydrolyzed in aqueous media to dimethoate (activation) and dimethoate carboxylic acid (degradation). It is used as an insecticide and acaricide on crops and ornamentals, but is not currently produced commercially in the U.S.
Used in Agricultural Industry:
Formothion is used as a systemic and contact insecticide for controlling spider mites, aphids, psyllids, mealy bugs, whiteflies, jassids, leaf miners, ermine moths, and fruit flies. It is applied to tree fruits, vines, olives, hops, cereals, sugar cane, and rice. Formothion is available as an emulsifiable concentrate and an ultra-low-volume spray. It is a U.S. EPA restricted Use Pesticide (RUP) and is not approved for use in EU countries.
Used in Pest Control:
Formothion is used as an acaricide and systemic insecticide to control sucking pests and internally feeding larvae in a variety of crops.
Air & Water Reactions
hydrolyzed by water especially under alkaline conditions. [EPA, 1998].
Reactivity Profile
Organophosphates, such as FORMOTHION, 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.
Hazard
Cholinesterase inhibitor.
Health Hazard
FORMOTHION is one of the least toxic systemic organophosphates. FORMOTHION is a compound of low to moderate toxicity. It causes the depression of cholinesterase, leading to accumulation of acetylcholine in the nervous system, which is believed to be responsible for the symptoms.
Fire Hazard
When heated to decomposition, FORMOTHION emits very toxic fumes of nitrogen oxides, phosphorus oxides and sulfur oxides. FORMOTHION is an organophosphorus insecticide. Some of these materials may burn but none of them ignite readily. Container may explode in heat of fire. Fire and runoff from fire control water may produce irritating or poisonous gases. Avoid alkaline pesticides; hydrolyzed by water especially under alkaline conditions.
Trade name
AFLIX?; ANTHIO?; ANTIO?; CP
53926?; S 6900?; SAN 244 I?; SAN 6913 I?; SAN
71071?; SPENCER S-6900?; VEL 4284?
Safety Profile
Poison by ingestion,
inhalation, sh contact, and intravenous
routes. Mutation data reported. When
heated to decomposition it emits very toxic
fumes of NOx, POx, and SOx. See also
ESTERS.
Potential Exposure
Formothion is an insecticide and acar icide for use on crops and ornamentals. Formothion is not
currently produced commercially in the U.S.
Metabolic pathway
Formothion is broken down in aqueous solution to approximately equal
amounts of dimethoate and dimethoate carboxylic acid, the first of which
is an activation step and the latter a degradative one. All studies which
have investigated the fate of formothion in biological systems have
identified these two metabolites but there is evidence that their formation
is purely base-catalysed and not enzyme-catalysed. In this respect, the
amide group of formothion is much more labile than that of dimethoate
since dimethoate carboxylic acid has only been reported in metabolic
studies and is not formed by base-catalysed hydrolysis of dimethoate.
Shipping
UN3018 Organophosphorus pesticides, liquid,
toxic, Hazard Class: 6.1; Labels: 6.1-Poisonous materials.
Degradation
Formothion is hydrolysed by water to dimethoate (2) and dimethoate
carboxylic acid (3). Dilute solutions in non-polar organic solvents are
stable (PM). El-Oshar and Dauterman (1977) investigated the hydrolysis
of [O-14C-methyl]formothion in 1.0 M phosphate buffer at pH values
between 5.5 and 8.0 at 37 °C. The amounts of unchanged formothion and
products were assessed after 30 min. At all pH values the amounts of
dimethoate (2) and dimethoate carboxylic acid (3) were approximately
equal, indicating that the rate of attack by the hydroxyl ion was equal at
both carbonyl groups. The rate of hydrolysis was pH dependent with
16.4% hydrolysis at pH 5.5, 65.2% hydrolysis at pH 7.0 and 96.7%
hydrolysis at pH 8.0 after 30 min. The route leading to dimethoate carboxylic
acid would yield N-methylformamide (4) as the additional product.
A suggested route for the base-catalysed hydrolysis of formothion
is shown in Scheme 1.
Toxicity evaluation
The acute oral
LD50 for rats is 365–500 mg/kg. Inhalation LC50 (4 h) for
rats is 3.2 mg/L air. NOEL (2 y) for rats is 80 mg/kg diet
(4 mg/kg/d). ADI is 0.02 mg/kg b.w.
Incompatibilities
Strong oxidizers may cause release of
toxic phosphorus oxides. Organophosphates, in the pres ence of strong reducing agents such as hydrides, may form
highly toxic and flammable phosphine gas. Keep away
from alkaline materials.
Waste Disposal
In accordance with 40CFR
165 recommendations for the disposal of pesticides and
pesticide containers. Must be disposed properly by follow ing package label directions or by contacting your local or federal environmental control agency, or by contacting
your regional EPA office.
Check Digit Verification of cas no
The CAS Registry Mumber 2540-82-1 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 2,5,4 and 0 respectively; the second part has 2 digits, 8 and 2 respectively.
Calculate Digit Verification of CAS Registry Number 2540-82:
(6*2)+(5*5)+(4*4)+(3*0)+(2*8)+(1*2)=71
71 % 10 = 1
So 2540-82-1 is a valid CAS Registry Number.
InChI:InChI=1/C6H12NO4PS2/c1-7(5-8)6(9)4-14-12(13,10-2)11-3/h5H,4H2,1-3H3
