298-00-0 Usage
Description
Parathion-methyl, also known as methyl parathion, is a synthetic organic thiophosphate compound and organophosphate acetylcholinesterase inhibitor. It is the methyl homolog of parathion and is used as a pesticide. Parathion-methyl is a white crystalline solid dissolved in a liquid solvent carrier, with a pungent odor. It is slightly soluble to insoluble in water and is toxic by inhalation, ingestion, and skin absorption.
Uses
Used in Agricultural Industry:
Parathion-methyl is used as an insecticide and acaricide for controlling boll weevils and many biting or sucking insect pests of agricultural crops. It is effective through contact, stomach, and respiratory action. The chemical is a restricted use pesticide, mainly used on cotton, rice, and fruit trees, as well as other crops such as corn, wheat, soybeans, and almonds.
Parathion-methyl is available in various formulations, including dust, emulsifiable concentrate, ULV liquid, microencapsules, and wettable powder. It is a derivative of Parathion (P192220) and belongs to a class of insecticides known as organophosphates. These chemicals act by interfering with the activities of cholinesterase, an enzyme essential for the proper functioning of the nervous systems of humans, animals, and insects.
Air & Water Reactions
Insoluble in water.
Reactivity Profile
METHYL PARATHION is half decomposed in 8 days at 40°C. When a sample was heated in a small test tube Parathion-methyl decomposed in a few minutes, the residue exploded (Food Chem. 4(1):42. 1956).
Hazard
Explosion risk when heated. Toxicby skin absorption, inhalation, and ingestion;cholinesterase inhibitor. Use has been restricted.Questionable carcinogen.
Health Hazard
Parathion-methyl is extremely toxic; the probable oral lethal dose is 5-50 mg/kg, or between 7 drops and 1 teaspoonful for a 150-lb. person. Chronic toxicity does not appear to be a major consideration.
Fire Hazard
Poisonous gases are produced in fire and when heated. Decomposition may lead to sufficient internal pressure to cause the container to rupture violently. Avoid oxidizing materials. Unstable. High temperatures (120F) cause decomposition.
Trade name
A-GRO?[C]; AI3-17292?; ATOMIC?[C];
AZOFOS?; AZOPHOS; BAMA BRAND?[C];
BAY 11405?; BAY E-601?; BLADAN M?;
CEKUMETHION?; CLEAN CROP?[C]; COTTON TOX
DUST?[C]; DALF?; DECLARE?; DEVITHION?;
DREXEL METHYL PARATHION 4E?[C]; DURHAM[C];
E 601?; EMMY?[C]; E-Z-FLO?[C]; FALL OUT?[C];
FMC NYNAMITE?[C]; FOLIDOC?; FOLIDOL-80?;
FOLIDOL M?; FOLIDOL M-40?; FOSFERNO M 50?;
GEARPHOS?; 8056HC?; KILEX PARATHION?;
ME-PARATHION?; MEPTOX?; METACID 50?;
METACIDE?; METAFOS?; METAPHOS?; METRON?;
METHYL-E 605?; METRON?; NITROX?; NITROX?
80; OLEOVOFOTOX?; PARAPEST M-50?; PENNCAP
M?; PENNCAP MLS?; QUINOPHOS?; SEIS-TRES
6-3?; SINAFID M-48?; SIXTY-THREE SPECIAL E.
C. INSECTICIDE?; TEKWAISA?; THIOPHENIT?;
THYLPAR M-50?; TOLL?; VERTAC METHYL
PARATHION TECHNISCH 80%?; WOFATOX 50 EC?
Contact allergens
A case of sensitization to
methyl-parathion was described in a female agricultural
worker with multiple sensitization.
Safety Profile
Poison by inhalation,
ingestion, skin contact, subcutaneous,
intravenous, and intraperitoneal routes. Fatal
poisoning can result from skin or eye
contact after very brief exposure to
concentrated solution. Experimental
teratogenic and reproductive effects.
Questionable carcinogen. Human mutation
data reported. A cholinesterase inhibitor
type of insecticide. When heated to
decomposition it emits very toxic fumes of
NOx, POx, and SOx.
Potential Exposure
A severely hazardous pesticide formulation. Alert: This material is used as an insecticide on over
50 crops, primarily cotton, and on several ornamentals
Carcinogenicity
When rats were given diets with
0, 0.5, 2.5, 12.5, and 50 ppm (0, 0.02, 0.1, 0.5, or 2 mg/kg/day
(males); 0, 0.02, 0.1, 0.7, or 3 mg/kg/day (females) for
12 months, neuronal degeneration and plasma, erythrocyte,
and brain cholinesterase inhibition occurred at 12.5 and
50 ppm .
Environmental Fate
Methyl parathion is mobile in soils and can leach into groundwater and enter surface water as runoff. The chemical breaks down though microbial degradation, aqueous photolysis, hydrolysis, and incorporation into soil organic matter; thus, it degrades rapidly in soil and water with a half-life <5 days. Photodegradation is rapid in aquatic environments with a half-life of 49 h. Bioconcentration is not expected to occur (U.S. EPA, 2006b).
Metabolic pathway
Parathion-methyl is a non-systemic insecticide and, where studied,
metabolism parallels that of parathion and f enitrothion. The major routes
of biotransformation involve desulfuration to the oxon analogue
(paraoxon-methyl) and hydrolysis to give dimethyl phosphate, dimethyl
phosphorothionate and 4-nitrophenol. Demethylation to give desmethylparathion-
methyl and reduction of the nitro group also occurs. As with
organophosphates, demethylation via glutathione-S-methyl transferases
in the liver and some other tissues is an important mechanism in
mammals. The major route of phase II metabolism involves conjugation
of 4-nitrophenol followed by excretion.
Shipping
UN3017 Organophosphorus pesticides, liquid,
toxic, flammable, flash point not ,23C, Hazard class: 6.1;
Labels: 6.1-Poisonous materials, 3.-Flammable liquid.
UN2783 Organophosphorus pesticides, solid, toxic, Hazard
Class: 6.1; Labels: 6.1-Poisonous material. UN2811 Toxic
solids, organic, n.o.s., Hazard Class: 6.1; Labels: 6.1-
Poisonous materials, Technical Name Required
Degradation
Parathion-methyl (1) is hydrolysed under acidic and alkaline conditions.
The rate is five times faster than for parathion. Upon heating it isomerises
via a thonwthiolo rearrangement to yield S-methylparahon-methyl (2)
(PM). The hydrolysis of the active anticholinesterase oxon analogue
(paraoxon-methyl) (3) is much faster than that of parathion-methyl. The
products of parathion-methyl hydrolysis were 4-nitrophenol (4) and
dimethyl phosphorothioate (5) (Thuma et al., 1983). Hydrolysis is much
more rapid in alkaline than in acidic or neutral media. Photodegradation
in natural sunlight led to the formation of O,O,S-trimethyl phosphorothioate
(6) and trimethyl phosphate (7) (Chukwudebe et al., 1989).
Zweiner et al. (1994) examined the photolysis of parathion-methyl in
aqueous solution after irradiation by unfiltered UV light. The major
metabolites, which were detected by GC-MS, were paraoxon-methyl (3)
and 4-nitrophenol (4). These conversions are shown in Scheme 1.
Incompatibilities
Incompatible with oxidizers, strong
bases; heat. Mixtures with magnesium, or endrin may be
violent or explosive. Slightly decomposed by acid solutions. Rapidly decomposed by alkalies. Explosive risk
when heated above 50C. The liquid xylene solution
decomposes violently @ 120C
Waste Disposal
Consult with environmental
regulatory agencies for guidance on acceptable disposal
practices. Generators of waste containing this contaminant
(≥100 kg/mo) must conform to EPA regulations governing
storage, transportation, treatment, and waste disposal.
Incineration (816C, 0.5 second minimum for primary combustion; 1204C, 1.0 second for secondary combustion)
with adequate scrubbing and ash disposal facilities.
In accordance with 40CFR165, follow recommendations
for the disposal of pesticides and pesticide containers.
Must be disposed properly by following 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 298-00-0 includes 6 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 3 digits, 2,9 and 8 respectively; the second part has 2 digits, 0 and 0 respectively.
Calculate Digit Verification of CAS Registry Number 298-00:
(5*2)+(4*9)+(3*8)+(2*0)+(1*0)=70
70 % 10 = 0
So 298-00-0 is a valid CAS Registry Number.
InChI:InChI=1/C8H10NO5PS/c1-13-15(12,14-2)16-8-5-3-7(4-6-8)9(10)11/h3-6H,1-2H3
298-00-0Relevant articles and documents
Ridgway et al.
, p. 1979 (1976)
A METHOD FOR NEUTRALIZATION OF TOXIN AGENTS, PESTICIDES AND THEIR HYDROLYSATES, AND A REAGENT FOR IT
-
Page 12, (2008/06/13)
This invention relates to the technology of ecotoxicants treatment, mainly chemical weapons (toxin agents), pesticides, hydrolysis products of toxin agents and pesticides. The method provides destruction of toxin agents, pesticides or their hydrolysates with further biodegradation of received products and can used for a wide range of ecotoxicants. The method can also be applied for cleaning of soils and objects contaminated with toxin agents and pesticides. In the claimed embodiments of the method, an amino acid reagent is used as a reagent for chemical neutralization of toxin agents, pesticides or their hydrolysates. Neutralization of ecotoxicants toxicity is carried out by application of a reagent containing an amino acid or a mixture of amino acids or peptides or derivatives of amino acids and peptides or their mixture in aqueous or aqueous organic medium. As the reagent hydrolysis products of protein containing factory waste can also be applied.
Selective Sulfur Oxygenation in Phosphoroamidate, Thionophosphate, and Thiophosphate Agrochemicals by Perfluoro-cis-2,3-dialkyloxaziridine
Terreni, Marco,Pregnolato, Massimo,Resnati, Giuseppe,Benfenati, Emilio
, p. 7981 - 7992 (2007/10/02)
Several organophsophorus agrochemicals 2a-g with thioether, phosphoramidic, phosphorothioic, and phosphorothionic functions were reacted with perfluoro-cis-2-n-butyl-3-n-propyloxaziridine 1.The selective oxygenation of sulfide function to give sulfoxide derivatives 3a-g occured in high yields without overoxidation to sulfone products.Sulfoxides 3a-e were further oxidized under mild conditions to the corresponding sulfones 4a-e.All the products are themselves of interest as analytical environmental standards and their preparation is described in detail.
