Chemical Properties
Pure fenitrothion is a yellowish brown liquid with an unpleasant odor. It is insoluble in water, but readily soluble in common organic solvents, such as acetone, alcohol, benzene, chlorinated hydrocarbons, dichloromethane, 2-propanol, toluene, in ethers, methanol, and xylene. It decomposes explosively. Fenitrothion is a contact insecticide and a selective acaricide of low ovicidal properties. Fenitrothion is effective against a wide range of pests, namely, penetrating, chewing, and sucking insect pests (coffee leaf-miners, locusts, rice stem borers, wheat bugs, fl our beetles, grain beetles, grain weevils) on cereals, cotton, orchard fruits, rice, vegetables, and forests. It may also be used as a fl y, mosquito, and cockroach residual contact spray for farms and public health programs. Fenitrothion is also effective against household insects and all nuisance insects. WHO confi rmed its effectiveness as a vector control agent for malaria. It is extensively used in other countries, including Japan, where parathion has been banned. Occupational workers are exposed to fenitrothion during mixing, loading/transportation, and fi eld applications.
General Description
Brownish-yellow oil. Used as a selective acaricide and a contact and stomach insecticide against chewing and sucking insects on rice, orchard fruits, vegetables, cereals, cotton and forest. Also used against flies, mosquitoes, and cockroaches.
Reactivity Profile
Organophosphates, such as FENITROTHION, 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, use may be
restricted.
Health Hazard
Fenitrothion is toxic to animals and humans. After prolonged periods of exposures to high concentrations of fenitrothion, occupational workers show poisoning. The symptoms include, but are not limited to, general malaise, fatigue, headache, loss of memory and ability to concentrate, anorexia, nausea, thirst, loss of weight, cramps, muscular weakness, and tremors, and at suffi ciently high dosage produce typical cholinergic poisoning. The formulation product, sumithion 50EC, causes delayed neurotoxicity in adult rats, as well as humans.
Health Hazard
This compound is an organophosphate insecticide. It is a highly toxic cholinesterase inhibitor, that acts on the nervous system. Does not cause delayed neurotoxicity and contact produces little irritation.
Potential Exposure
A potential danger to those involved
in the manufacture, formulation, and application of this
insecticide. It is a selective acaricide; and a contact and
stomach insecticide. Used to control chewing and sucking
insects on rice, orchard fruit; vegetables, cereals, cotton,
and in forests. Also protects against flies, mosquitoes, and
cockroaches
Fire Hazard
When heated to decomposition, FENITROTHION emits very toxic fumes of oxides of nitrogen, phosphorus and sulfur. Decomposition at 212-284F produces a mixture of organophosphorus polymers. Unstable in alkaline media. Stable for 2 years if stored at 68-77F. Do not store above 104F.
First aid
If this chemical gets into the eyes, remove any
contact lenses at once and irrigate immediately for at least
15 minutes, occasionally lifting upper and lower lids. Seek
medical attention immediately. If this chemical contacts the
skin, remove contaminated clothing and wash immediately
with soap and water. Speed in removing material from skin
is of extreme importance. Shampoo hair promptly if contaminated. Seek medical attention immediately. If this chemical
has been inhaled, remove from exposure, begin rescue
breathing (using universal precautions, including resuscitation mask) if breathing has stopped and CPR if heart action
has stopped. Transfer promptly to a medical facility. When
this chemical has been swallowed, get medical attention.
Give large quantities of water and induce vomiting. Do not
make an unconscious person vomit. Effects may be delayed.
Keep victim under medical observation
Shipping
UN3017 Organophosphorus pesticides, liquid,
toxic, flammable, flash point not ,23C, Hazard class: 6.1;
Labels: 6.1-Poisonous materials, 3-Flammable liquid.
UN2810 Toxic liquids, organic, n.o.s., Hazard Class: 6.1;
Labels: 6.1-Poisonous materials, Technical Name Required
Incompatibilities
Incompatible with oxidizers (chlorates,
nitrates, peroxides, permanganates, perchlorates, chlorine,
bromine, fluorine, etc.); contact may cause fires or explosions. Keep away from alkaline materials, strong bases,strong acids, oxoacids, epoxides. Strong oxidizers may cause
release of toxic phosphorus oxides. Organophosphates, in the
presence of strong reducing agents such as hydrides, may
form highly toxic and flammable phosphine gas. Keep away
from alkaline materials
Waste Disposal
Incineration (for large
amounts); alkaline hydrolysis and landfill (for small
amounts). 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.
Uses
Fenitrothion is used to control sucking, chewing and boring
insects in cereals, soft fruit, tropical fruit, vines, sugar cane, vegetables,
turf and forestry. It is also used as a public health insecticide for the
control of flies, cockroaches and mosquitoes. Other uses are for the control
of stored product pests and locusts.
Definition
ChEBI: An organic thiophosphate that is O,O-dimethyl O-phenyl phosphorothioate substituted by a methyl group at position 3 and a nitro group at position 4.
Flammability and Explosibility
Notclassified
Agricultural Uses
Insecticide, Acaracide: Not approved for use in EU countries. Registered
for use in the U.S. This is a selective acaricide and a contact
and stomach insecticide. Fenitrothion is a contact insecticide
and selective acaricide of low ovicidal properties. It is
considered an acetylcholinesterase inhibitor. Fenitrothion
is effective against a wide range of pests, i.e. penetrating,
chewing and sucking insect pests (coffee leafminers,
locusts, rice stem borers, wheat bugs, flour beetles, grain
beetles, grain weevils) on cereals, cotton, orchard fruits,
rice, vegetables, and forests. It may also be used as a fly,
mosquito, and cockroach residual contact spray for farms
and public health programs. Fenitrothion is also effective
against household insects and all of the nuisance insects
listed by the World Health Organization. Its effectiveness as
a vector control agent for malaria is confirmed by the World
Health Organization. Fenitrothion is non-systemic, and
non-persistent. Fenitrothion was introduced in 1959 by both
Sumitomo Chemical Company and Bayer Leverkusen and
later by American Cyanamid Company. Fenitrothion is far
less toxic than parathion with a range of insecticidal activity
that is very similar and is similar enough in structure to be
produced in the same factories. The difference in precursor
chemicals might make it somewhat more expensive, but it is
heavily used in other countries, including Japan, where parathion
has been banned. Fenitrothion comes in dust, emulsifiable
concentrate, flowable, fogging concentrate, granules,
ULV, oil-based liquid spray, and wettable powder formultaions.
It is compatible with other neutral insecticides.
Trade name
ACCOTHION®; ACEOTHION®; AGRIA
1050®; AGRIYA 1050®; AGROTHION®; AMERICAN
CYANAMID CL-47,300®; ARBOGAL®; BAY 41831®;
BAYER 41831®; BAYER S 5660®; CEKUTROTHION®;
CL 47300®; CP47114®; CYFEN®; CYTEL®;
CYTEN®; DICATHION®; DICOFEN®; DYBAR®;
EI 47300®; FALITHION®; FENITEX®; FENITOX®;
FENSTAN®; FOLETHION®; FOLITHION®; H-35-F
87 (BVM)®; 8057HC®; KALEIT®; KEEN SUPERKILL
ANT AND ROACH EXTERMINATOR®; KILLGERM
TETRACIDE INSECTICIDAL SPRAY®; KOTION®;
MEP (PESTICIDE)®; METATHION®; METATHIONE®;
METATION®; MICROMITE®; MONSANTO CP
47114®; NITROPHOS®; NOVATHION®; NUVAND®;
NUVANOL®; OLEOSUMIFENE®; OMS 43®;
OVADOFOS®; PENNWALT C-4852; PESTROY®; S
112A®; S 5660®; SMT®; SUMITHION®[C]; TURBAIR
GRAIN STORAGE INSECTICIDE®; VERTHION®
Metabolic pathway
Fenitrothion is a non-systemic insecticide, the biotransformations and
environmental fate of which have been intensively studied and reviewed.
Metabolism has been studied in mammals (including humans), birds,
fish, crustacea, molluscs, insects, algae, plants and soil. The major routes
of biotransformation involve desulfuration to the oxon analogue
(fenitrooxon) and hydrolysis to give dimethyl phosphate, O,O-dimethyl
phosphorothioate and 3-methyl-4-nitrophenol. Demethylation to give
desmethylfenitrothion and its decomposition products, reduction of
the nitro group and oxidation of the ring methyl group also
occur. Demethylation via glutathione-S-methyl transferases in the liver
is a particularly important mechanism in mammals. Reduction of
the nitro group to an amino group is important in anaerobic soils
and ruminants but this has also been shown to occur in rats, rabbits
and humans where it is presumably carried out by bacteria in the gut.
Oxidation of the 3-methyl group to hydroxymethyl and carboxylate
has been shown to be a degradative route in birds. The major routes of
phase II metabolism involve conjugation of 3-methyl-4-nitrophenol to the
glucoside in plants and insects, to the sulfate ester in birds and the sulfate
ester and glucuronide in mammals.
Metabolism
The main biotransformation routes involve oxidative
desulfuration to the oxon and dearylation to give
dimethyl hydrogen phosphate, O,O-dimethyl hydrogen
phosphorothioate and 3-methyl-4-nitrophenol. Demethylation
dependent on glutathion-S-alkyl transferase is particularly
important in mammals.Oxidation of the 3-methyl
group to hydroxymethyl and then carboxyl group is also
a degradative route. Reduction of the nitro group to an
amino group occurs in anaerobic soils and ruminants. The
DT50 in soils under upland and submerged conditions were
12–28 and 4–20 d, respectively.
storage
Color Code—Blue: Health Hazard/Poison: Store ina secure poison location. Prior to working with this chemicalyou should be trained on its proper handling and storage.Prior to working with this chemical you should be trained onits proper handling and storage. Store in tightly closed containers in a cool, well-ventilated area away from oxidizers.Where possible, automatically pump liquid from drums orother storage containers to process containers.
Degradation
Fenitrothion is relatively stable to hydrolysis under normal conditions
(PM). Mikami et al. (1985) reported the hydrolysis of fenitrothion between
pH 5 and 10. Below pH 7 hydrolysis occurred by a pH-independent
mechanism and above pH 9 by a base-catalysed process. At intermediate
pH values both mechanisms were operative. The major mechanism below
pH 8 was demethylation to give desmethylfenitrothion and above
pH 9, cleavage of the P-O-aryl bond gave 3-methyl-4-nitrophenol.
Toxicity evaluation
The acute oral LD50 values in mammals
range from 330 mg/kg in rats to 1850 mg/kg in the guineapig.
Inhalation LC50 (4 h) for rats is >1.2 mg/L air. NOEL
(2 y) for rats and mice is 10 mg/kg diet (0.5 mg/kg/d). ADI
is 5 μg/kg b.w.
