|
| | Oxamyl Chemical Properties |
| Melting point | 100°C | | density | 0.9700 | | vapor pressure | 5.1×10-5Pa (25 °C) | | refractive index | 1.6630 (estimate) | | storage temp. | 0-6°C | | solubility | Chloroform: Slightly Soluble,Methanol: Slightly Soluble | | pka | 10.48±0.46(Predicted) | | form | neat | | Water Solubility | 28 g/100 mL | | BRN | 2212753 | | Stability: | Hygroscopic | | CAS DataBase Reference | 23135-22-0(CAS DataBase Reference) | | NIST Chemistry Reference | Oxamyl(23135-22-0) | | EPA Substance Registry System | Oxamyl (23135-22-0) |
| | Oxamyl Usage And Synthesis |
| Description | Oxamyl, is also called N,N-dimethyl-2-methylcarbamoyloxyimino-
2-(methylthio)acetamide (IUPAC), consists of colorless
crystals, which are readily soluble in water, methanol,
ethanol, acetone, and fairly soluble in toluene.
Oxamyl is produced by chlorination of the oxime of
methylglycolate, reaction with methanethiol and alkali,
and conversion to the carbamate with methyl isocyanate. | | Uses | Insecticide, nematocide, acaricide. | | Uses | Oxamyl is a broad spectrum systemic insecticide/nematicide. It
exhibits both oral and contact toxicity to control both sucking and chewing
insects and mites in a wide variety of row crops, fruits, vegetables and
ornamentals. | | Uses | Oxamyl is a pesticide used in the treatment and protection of crops from parasites and insects. | | Definition | ChEBI: Oxamyl is a carbamate ester. It has a role as an EC 3.1.1.7 (acetylcholinesterase) inhibitor, a carbamate insecticide, an acaricide, an antinematodal drug and an agrochemical. It is functionally related to a methylcarbamic acid. | | Agricultural Uses | Insecticide, Nematicide, Acaricide: A systemic and contact insecticide/acaricide and
nematicide, oxamyl is a restricted use pesticide used on
apples, bananas, carrots, celery, citrus, cotton, cucumbers,
eggplants, garlic, ginger, muskmelon (including cantaloupe
and honeydew melon), onion (dry bulb), peanuts,
pears, peppers, peppermint, pineapples, plantains, potatoes,
pumpkins, soybeans, spearmint, squash, sweet potatoes,
tobacco, tomatoes, watermelons, yams. Oxamyl is
also used on non-bearing apple, cherry, citrus, peach, pear,
and tobacco. It is applied directly onto plants or the soilsurface. It is available in both liquid and granular form, but
the granular form is banned in the U.S. It has no residential
use. Registered for use in EU countries[115 | | Trade name | BLADE®; D-1410®; DPX 1410®;
INSECTICIDE-NEMACIDE 1410®; OXAMYL
CARBAMATE INSECTICIDE®; THIOXAMYL®;
VYDATE®; VYDATE® 10G; VYDATE L®; VYDATE
INSECTICIDE/NEMATICIDE®; VYDATE OXAMYL
INSECTICIDE/NEMATOCIDE®[C] | | Safety Profile | Poison by ingestion,
skin contact, and inhalation. Experimental
reproductive effects. Moderately toxic by
skin contact. When heated to decomposition
it emits very toxic fumes of NOx and SOx | | Potential Exposure | Oxamyl is a white crystalline solid. Sulfur or
garlic-like odor. Molecular weight=219.3 | | Environmental Fate | Soil. Oxamyl rapidly degraded in a loamy sand and fine sand soil at 25°C to carbon
dioxide and the intermediate methyl N-hydroxy-N,N-dimethyl-1-thiooxaminidate (Rajagopol
et al., 1984). The reported half-life in soil is approximately one week (Worthing
and Hance, 1991). Ou and Rao (1986) reported a half-life in soil of 8–50 days. The reported
half-lives of oxamyl in Pitstone, Devizes, Sutton Veany and Mepal soils at 15°C were
reported to be 10.2–13.1, 6.2, 7.1 and 17.8 days, respectively (Bromilow et al., 1980).
Smelt et al. (1987) reported that oxamyl degraded at a higher rate in field plots after
repeated applications of this nematocide than in soils that received no treatment. The
repeated applications of oxamyl to soils probably induced microbial activity, which
resulted in the accelerated disappearance of this compound.
Harvey and Han (1978) reported a half-life of 8 days for oxamyl in soil.
Groundwater. According to the U.S. EPA (1986) oxamyl has a high potential to leach
to groundwater.
Plant. Dislodgable residues of oxamyl on cotton leaf 0, 24, 48, 72 and 96 hours after
application (0.41 kg/ha) were 1.5, 1.1, 1.2, 0.85 and 0.76 mg/m2, respectively (Buck et al.,
1980).
Chemical/Physical. The hydrolysis half-lives of oxamyl in a sterile 1% ethanol/water
solution at 25°C and pH values of 4.5, 6.0, 7.0 and 8.0, were 300, 17, 1.6 and 0.20 weeks,
respectively (Chapman and Cole, 1982). Under alkaline conditions, oxam | | Metabolic pathway | Oxamyl degrades in soils, plants and animals following common metabolic
pathways. Primary degradation reactions include the hydrolysis of
the carbamate ester to yield the corresponding oxyimidothioate and
nitrile. Other major metabolic reactions include N-demethylation and the
hydration/oxidation of the nitriles to the corresponding amides and
acids. The majority of the oxamyl metabolites are recovered as conjugates
in plants and animals. No metabolites containing the oxidised thiomethyl
group were observed. The primary degradation/metabolic pathways of
oxamyl are presented in Scheme 1. | | Shipping | UN2811 Toxic solids, organic, n.o.s., Hazard
Class: 6.1; Labels: 6.1-Poisonous materials, Technical
Name Required. UN2991 Carbamate pesticides, liquid,
toxic, flammable, flash point ＜23°C, Hazard Class: 6.1;
Labels: 6.1-Poisonous material, 3-Flammable liquid. | | Degradation | Oxamyl (1) was stable under acidic conditions but hydrolysed rapidly
under basic conditions at 25 °C with DT50 values of >30 days at pH 5,
8 days at pH 7, and 3 hours at pH 9 (McNally and Wheeler, 1988).
Cleavage of the methylcarbamoyl bond yielded methyl 2-( dimethylamino)-
N-hydroxy-2-oxoethanimidothioate (2) as the primary hydrolysis
product.
Exposure to artificial sunlight enhanced the degradation of oxamyl in
pH 5 solution (DT50 7 vs. >30 days) to yield compound 2 (McNally,
1988). Rapid degradation of oxamyl was also observed in natural water
exposed to natural sunlight (DT50 <1 day, Harvey and Han, 1978a).
Compound 2 and its geometrical isomer (3) were major products
observed in natural and distilled water exposed to artificial and natural
sunlight. Further hydrolysis yielded (dimethy1amino)oxoacetica cid (4) as
a minor photodegradation product in natural water exposed to natural
sunlight. | | Incompatibilities | Compounds of the carboxyl group react
with all bases, both inorganic and organic (i.e., amines)
releasing substantial heat, water and a salt that may be
harmful. Incompatible with arsenic compounds (releases
hydrogen cyanide gas), diazo compounds, dithiocarbamates,
isocyanates, mercaptans, nitrides, and sulfides
(releasing heat, toxic, and possibly flammable gases), thiosulfates
and dithionites (releasing hydrogen sulfate and oxides
of sulfur). | | Waste Disposal | Consult with environmental
regulatory agencies for guidance on acceptable disposal
2264 Oxamyl
practices. Generators of waste containing this contaminant
(≥100 kg/mo) must conform with EPA regulations governing
storage, transportation, treatment, and waste disposal.
Small quantities may be treated with alkali and buried in a
landfill. 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. |
| | Oxamyl Preparation Products And Raw materials |
|
