Chemical Properties
Tan colored liquid; sulfide odor. Soluble in organic solvents; insoluble in water.
General Description
Tan-colored liquid with a sulfide-like odor.
Reactivity Profile
Organothiophosphates 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. Questionable carcinogen.
Potential Exposure
A potential danger to those involved in the manufacture, formulation, and application of this insecticide that is used for control of certain lepidopterous, dipterous, and hemipterous insects on cotton, etc.
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.
Shipping
UN3018 Organophosphorus pesticides, liquid, toxic, Hazard Class: 6.1; Labels: 6.1-Poisonous materials.
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
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.
Definition
ChEBI: Sulprofos is an organic thiophosphate, an organothiophosphate insecticide and an organosulfur compound. It has a role as an EC 3.1.1.7 (acetylcholinesterase) inhibitor and an agrochemical. It is functionally related to a 4-(methylsulfanyl)phenol.
Environmental Fate
Biological. From the first-order biotic and abiotic rate constants of sulprofos in estu-
arine water and sediment/water systems, the estimated biodegradation half-lives were
19.5–61.6 and 3.5–19 days, respectively (Walker et al., 1988).
Photolytic. When sulprofos was exposed to sunlight as deposits on cotton foliage, glass
surfaces and in aqueous solution, the insecticide degraded rapidly (half-life <2 days).
Irradiation of sulprofos in aqueous solution using UV light (λ >290
Chemical/Physical. Emits toxic oxides of sulfur and phosphorus when heated to
decomposition (Lewis, 1990).
Metabolic pathway
Sulprofos is an organophosphorus insecticide possessing a 4-(methylthio)
phenyl group and as such its metabolic fate has much in common
with fenthion with which it also has the phosphorothioate (P=S) group in
common. The major route of sulprofos metabolism is by oxidation to the
sulfoxide and more slowly to the sulfone. The additional route of bioactivation
is through oxidative desulfuration to form the sulprofos oxon
and all five oxidative metabolites (sulprofos sulfoxide, sulprofos sulfone,
sulprofos oxon, sulprofos oxon sulfoxide and sulprofos oxon sulfone)
have been detected in rats. Degradative metabolism by hydrolysis or oxidative
dearylation to the phenols occurs rapidly. Stage II metabolism in
mammals involves the rapid conjugation of the phenolic dearylation
products. The fate of the S-propyl phosphorodithioate group has not
apparently been reported.
Metabolism
Major metabolic routes
are by oxidation to the sulfoxide and sulfone and oxidative
desulfuration to the oxons. Detoxification by dearylation
to the phenols occurs rapidly. Sulprofos is degraded in soil
with a half-life ranging from a few days to several weeks,
depending on the soil type.
Degradation
The half-lives in aqueous solution at pH values 4,7 and 9 were 26,151 and
51 days, respectively. Its DT50 was less than two days when a thin film
was exposed to sunlight. Ivie and Bull (1976), examined the photodecomposition
in sunlight of sulprofos on cotton leaves, glass surfaces
and aqueous solutions. The major metabolites were sulprofos sulfoxide
(2) and sulfone (3), with minor amounts of sulprofos oxon sulfoxide (4)
and the three possible phenolic hydrolysis products (5, 6 and 7). Photodecomposition
is thus via thiooxidation, oxidative desulfuration and
cleavage of the P-O-aryl group as shown in Scheme 1. A large number of
minor photolysis products which could not be identified were also
formed.
Toxicity evaluation
The acute
oral LD50 for rats is 176–304 mg/kg. Inhalation LC50
(4 h) for rats is >4.1 mg/L air. NOEL (2 yr) for rats is
6 mg/kg diet (0.3 mg/kg/d). ADI is 3 μg/kg b.w. Sulprofos
administered to rats is rapidly metabolized, and 92% of
the dose is excreted within 24 h.
