チオりん酸O,O-ジエチルO-(5-フェニル-3-イソオキサゾリル)

Biological Exposure Indices (BEI) [ACGIH] - Acetylcholinesterase activity in red blood cells = 70% of individual's baseline; Butylcholinesterase activity in serum or plasma = 60% of individual's baseline; Sample at end of shift; [TLVs and BEIs]

If material on fire or involved in fire: Do not extinguish fire unless flow can be stopped. Use water in flooding quantities as fog. Solid streams of water may be ineffective. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. Use "alcohol" foam, dry chemical or carbon dioxide. /Organophosphorus pesticides, liquid, flammable, toxic; Organophosphorus pesticides, liquid, toxic/

If material on fire or involved in fire: Use water in flooding quantities as fog. Extinguish fire using agent suitable for type of surrounding fire. (Material itself does not burn or burns with difficulty.) /Organophosphorus pesticides, solid, toxic/

Environmental considerations: Air spill: Apply water spray or mist to knock down vapors. /Organophosphorus pesticides, liquid, flammable, toxic; Organophosphorus pesticides, liquid, toxic; Organophosphorus pesticides, solid, toxic/

Environmental considerations: Water spill: Use natural barriers or oil spill control booms to limit spill travel. Remove trapped material with suction hoses. /Organophosphorus pesticides, liquid, flammable, toxic; Organophosphorus pesticides, liquid, toxic; Organophosphorus pesticides, solid, toxic/

Environmental considerations: Land spill: Dig a pit, pond, lagoon, holding area to contain liquid or solid material. /SRP: If time permits, pits, ponds, lagoons, soak holes, or holding areas should be sealed with an impermeable flexible membrane liner./ Dike surface flow using soil, sand bags, foamed polyurethane, or foamed concrete. Absorb bulk liquid with fly ash, cement powder, or commercial sorbents. /Organophosphorus pesticides, liquid, flammable, toxic; Organophosphorus pesticides, liquid, toxic; Organophosphorus pesticides, solid, toxic/

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational exposure or environmental contamination. Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in soil or water; effects on animal, aquatic, and plant life; and conformance with environmental and public health regulations.

If material not on fire and not involved in fire: Keep sparks, flames, and other sources of ignition away. Keep material out of water sources and sewers. /Organophosphorus pesticides, solid, toxic

If material not on fire and not involved in fire: Keep sparks, flames, and other sources of ignition away. Keep material out of water sources and sewers. Build dikes to contain flow as necessary. Attempt to stop leak if without undue personnel hazard. Use water spray to knock-down vapors. /Organophosphorus pesticides, liquid, toxic/

If material not on fire and not involved in fire: Keep sparks, flames, and other sources of ignition away. Keep material out of water sources and sewers. Build dikes to contain flow as necessary. Use water spray to knock-down vapors. /Organophosphorus pesticides, liquid, flammable, toxic/

Personnel protection: Avoid breathing dusts, and fumes from burning material. Keep upwind. Avoid bodily contact with the material. Do not handle broken packages unless wearing appropriate personal protective equipment. Wash away any material which may have contacted the body with copious amounts of water or soap and water. /Organophosphorus pesticides, solid, toxic/

For more Preventive Measures (Complete) data for ISOXATHION (8 total), please visit the HSDB record page.

Because different classes of enzymes may be inhibited, the effects of organophosphorus pesticide poisoning may be complex and potentially at least could involve interactions with drugs as well as with other pesticides or chemicals. Potentiation may also involve solvents or other components of formulated pesticides. Certain drugs such a phenothiazines, antihistamines, CNS depressants, barbiturates, xanthines (theophylline), aminoglycosides and parasympathomimetic agents are to be avoided because of increased toxicity. /Organophosphorus pesticides/

LC50 Cyprinus carpio 2.1 mg/l/48 hr /Conditions of bioassay not specified/

LD50 Chicken oral 21,600 ug/kg

LC50 Daphnia pulex 0.0052 mg/L/3 hr /Conditions of bioassay not specified/

LC50 Bufo bufo japonicus (Toad; 25-35 days, 0.34 g tadpole) 5,100 ug/L/72 hr; 12,000 ug/L/24 hr; 5,300 ug/L/48 hr; 5,100 ug/L/96 hr; static /Formulated product/

For more Ecotoxicity Values (Complete) data for ISOXATHION (6 total), please visit the HSDB record page.

TERRESTRIAL FATE: Based on a classification scheme(1), a Koc value of 14,568(2) indicates that isoxathion is expected to be immobile in soil(SRC). Volatilization of isoxathion from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 6.1X10-8 atm-cu m/mole(SRC), using a fragment constant estimation method(3). Isoxathion is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 2.2X10-6 mm Hg(SRC), determined from a fragment constant method(4). Isoxathion has been shown to biodegrade in soil with the major metabolic pathway being via the formation of 3-hydroxy-5-phenylisoxazole to 5-phenyl-4-oxazolin-2-one, benzoylacetamide and benzoic acid(5).

AQUATIC FATE: Based on a classification scheme(1), a Koc value of 14,568(2) indicates that isoxathion is expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is not expected(3) based upon an estimated Henry's Law constant of 6.1X10-8 atm-cu m/mole(SRC), developed using a fragment constant estimation method(4). According to a classification scheme(5), an estimated BCF of 150(SRC), from its log Kow of 3.73(6) and a regression-derived equation(7), suggests the potential for bioconcentration in aquatic organisms is high(SRC). However, aquatic organisms readily metabolize this class of compounds(8) and organophosphates can be altered chemically(9) once released into the environment. Aqueous photolytic half-lives of 12-18 days have been reported, with the addition of humic acids increasing the rate of photolysis by up to 25%(10). Percent biodegradation of isoxathion from three ponds near Nagoya City, Japan ranged from 0-31% after four days of incubation; compared to aniline (biodegradation rate as high as 86%), this compound was classified as not expected to biodegrade rapidly(11).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), isoxathion, which has an estimated vapor pressure of 2.2X10-6 mm Hg at 25 °C(SRC), determined from a fragment constant method(2), will exist in both the vapor and particulate phases in the ambient atmosphere. Vapor-phase isoxathion is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC); the half-life for this reaction in air is estimated to be 3 hrs(SRC), calculated from its rate constant of 1.2X10-10 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). Particulate-phase isoxathion may be removed from the air by wet and dry deposition(SRC).

Measurement of whole blood-AChE is the most widely adopted method for monitoring the effects of occupational exposure to organophosphorus insecticides. Physiological variations in blood ChE levels occur in a healthy person and are seen among a population. It has been estimated that the coefficient of variation for AChE activity in samples from an individual is 8-11%, and that a decrease of 23% below pre-exposure level may, therefore, be considered significant. If the average of several pre-exposure values were available, then a decrease of 17% would be significant. It has been recommended that, if measured activity is reduced by 30% or more of the pre-exposure value, AChE measurements should be repeated at appropriate intervals to confirm the results. Depressions of AChE or ChE in excess of 20-25% are considered diagnostic of exposure but not, necessarily, indicative of hazard. Depressions of 30-50% or more are considered indicators for removal of an exposed individual from further contact with pesticides until levels return to normal. /Organophosphorus Pesticides/

...Organophosphorus pesticides may undergo hydrolysis in vivo to yield substituted phosphoric acids that are subsequently excreted in urine. Advances in gas chromatography and combined gas chromatography/mass spectrometry (GC/MS) have made it possible to analyse the urine of exposed persons for the presence of appropriate metabolites. It is usually necessary to preserve the sample by the addition of chloroform, to concentrate or extract the metabolite(s), and to convert them to suitably-volatile derivatives that can be detected by GC. Obviously, access to a well-equipped analytical laboratory, capable of the quick processing of samples, is a necessary factor if monitoring by urine analysis is proposed. However, in some cases, simpler and sensitive colorimetric tests are available for screening the urine of exposed persons. Thus, 4-nitrophenol can be measured directly in the urine of workers exposed to parathion. Consideration of the concentration of metabolite(s) in the urine can be helpful in determining patterns of exposure, and these concentrations can be calibrated against the effects on AChE for a particular pesticide. However, the time-course and peak of excretion of metabolites appears to vary according to dose, so that serial sampling and analyses of urine are desirable. Levels of metabolite alone cannot be considered a guide to hazard. This is obvious when it is realized that pesticides that have very different toxicities may yield identical acidic metabolites. Thus, the level of metabolites in urine, after exposure to sufficient amounts of the very toxic parathion-methyl to depress blood-AChE to 50%, will be much lower than that of the identical metabolites, following exposure to the related fenitrothion, which is about 40 times less toxic. /Organophosphorus Pesticides/

SRP: Workers should undergo an annual medical exam. Contraindications for work with organophosporous pesticides are organic diseases of the CNS, mental disorders and epilepsy, and pronounced endocrine disorders. Blood cholinesterase, both plasma and RBC, must be determined before work starts. In the event of prolonged work periods, this activity should be determined at intervals of 3-4 days. Persons exhibiting a fall in cholinesterase activity of 25% or more must be transferred to other work where they are not exposed until cholinesterase activity is restored. /Organophosphorous pesticides/

The Koc of isoxathion in turf grass soil is 14,568(1). According to a classification scheme(2), this estimated Koc value suggests that isoxathion is expected to be immobile in soil. Rf (retention factor) values for isoxathion were reported as 0.63, 0.50, and 0.62, using three Japanese soils - Hiratsuka (sandy loam, 69.8% sand, 19.6% silt, 10.6% clay, 3.2% organic matter, pH 5.9), Tanashi (loam, 60.5% sand, 30.2% silt, 9.3% clay, 8.4% organic matter, pH 6.0), and Yasu (sandy loam, 56.6% sand, 29.9% silt, 1.56% clay, 1.8% organic matter, pH 4.9), respectively(3).

URBAN/SUBURBAN: Air samples from Kitayushu City, Japan during 21-22 July 1991 and 23-24 April, 1992 were tested for isoxathion; concentrations of 0.63 ng/cu m and not detected (detection limit = 0.2 ng/cu m), respectively, were reported(1).

SOURCE DOMINATED: Isoxathion was detected, not quantified in air samples collected from golf courses in the Kanagawa Prefecture, Japan; levels were higher in daytime(1).

/SIGNS AND SYMPTOMS/ Signs and symptoms of acute intoxication by organophosphorus insecticides include muscarinic, nicotinic, and central nervous system (CNS) manifestations. Symptoms may develop rapidly, or there may be a delay of several hours after exposure before they become evident. The delay tends to be longer in the case of more lipophilic compounds, which also require metabolic activation. Symptoms may increase in severity for more than one day and may last for several days. In severe cases, respiratory failure is a dominant effect. /Organophosphorus Pesticides/

/SIGNS AND SYMPTOMS/ Although many epidemiological studies have been carried out, few controlled studies on man have been reported. It is generally recognized that there are behavioural and psychic changes during overt clinical poisoning by organophosphorus insecticides and that these may take several months to regress. However, there is no information to suggest that effects occur at exposure levels that do not either alter ChE levels or produce physical symptoms. ...Much /of the work on different aspects of behavior as affected by organophasphates/ was based on generalized complaints from workers occupationally exposed to many agricultural chemicals (and probably also to automobile fuels and lubricants and to alcohol). In summary, ...in human subjects sufficiently exposed to organophosphates to depress plasma- or erythrocyte-ChEs, some or all of the following behavioral variables might be impaired. In cognition: vigilance, information processing and psychomotor speed, and memory; in speech: both performance and perception; in psychic state: increased tendencies to depression, anxiety, and irritability; and in EEG records: a tendency to faster frequencies and higher voltages. /Organophosphorus Pesticides/

/SIGNS AND SYMPTOMS/ Respiratory and ocular symptoms are expected to appear first after exposure to airborne organophosphorus pesticides. /Organophosphorus pesticides/

/SIGNS AND SYMPTOMS/ The clinical picture of organophosphorus intoxication results from accumulation of ACh at nerve endings. ...The symptoms can be summarized in three groups as follows: (a) Muscarinic manifestations- increased bronchial secretion, excessive sweating, salivation, and lachrymation; pinpoint pupils, bronchoconstriction, abdominal cramps (vomiting and diarrhea); and bradycardia. (b) Nicotinic manifestations- fasciculation of fine muscles and, in more severe cases, of diaphragm and respiratory muscles; and tachycardia. (c) Central nervous system manifestations- headache, dizziness, restlessness, and anxiety; mental confusion, convulsions, and coma; and depression of the respiratory centre. All these symptoms can occur in different combinations and can vary in time of onset, sequence, and duration, depending on the chemical, dose, and route of exposure. Mild poisoning might include muscarinic and nicotinic signs only. Severe cases always show central nervous system involvement; the clinical picture is dominated by respiratory failure, sometimes leading to pulmonary edema, due to the combination of the above-mentioned symptoms. /Organophosphorus Pesticides/

AEROBIC: Half-lives in turf grass soil and other soils of 5 and 15-40 days, respectively, have been reported for isoxathion(1). Isoxathion was added to fresh water inoculums from three ponds near Nagoya City, Japan and using the Handai biodegradation test method(2). Biodegradation rates were measured at different times over the years were as follows: Ara-ike (irrigation reservoir), June 1991 thru October 1992, 6-23% after 4-day incubation; Makinoga-oke (located in a park near a residential area and a golf course), July 1990 thru April 1991, 0-31% after 4-day incubation; Tatsuga-ike (boating pond in a park), July 1989-March 1992, 14-22% after 4-day incubation(2). In comparison to aniline which exhibited a biodegradation rate as high as 86%, this compound is not expected to biodegrade rapidly(2).

30 ppm of 14C-labeled isoxathion was incubated in 50 g of three Japanese soils - Hiratsuka (sandy loam, 69.8% sand, 19.6% silt, 10.6% clay, 3.2% organic matter, pH 5.9), Tanashi (loam, 60.5% sand, 30.2% silt, 9.3% clay, 8.4% organic matter, pH 6.0), and Yasu (sandy loam, 56.6% sand, 29.9% silt, 1.56% clay, 1.8% organic matter, pH 4.9). Soils were maintained at 60% field capacity for non-flooded conditions and at 150% field capacity for flooded conditions. %14C-isoxathion recovered from non-flooded Hiratsuka soil was 75, 51, and 32 after 20, 40, and 60 days, respectively, initial half-life = 44 days; % recovered from flooded Hiratsuka soil - 46, 14, and 5, respectively, initial half-life = 18 days. %14C-isoxathion recovered from non-flooded Tanashi soil was 69, 17, and 10 after 10, 30, and 45 days, respectively, initial half-life = 19 days). %14C-isoxathion recovered from non-flooded Yasu soil was 80 and 47 after 10 and 20 days, respectively, initial half-life = 31 days(1). The major metabolic pathway is via the formation of 3-hydroxy-5-phenylisoxazole to 5-phenyl-4-oxazolin-2-one, benzoylacetamide and benzoic acid(1).

Used as contact and stomach insecticide for fruits, tea, tobacco, ornamentals, rice, sugarcane, vegetables, turf, and trees; [HSDB]

No longer registered as a pesticide for use in the US; [HSDB] Banned in the EU for use as pesticide for plant protection; [eChemPortal: ESIS]

Farming (Pesticides) [Category: Industry]

For isoxathion (USEPA/OPP Pesticide Code: 057802) there are 0 labels match. /SRP: Not registered for current use in the U.S., but approved pesticide uses may change periodically and so federal, state and local authorities must be consulted for currently approved uses./

Control of scale insects, aphids, hoppers, beetles, and caterpillars on citrus fruit, tea, tobacco, garden trees, rice, sugarcane, and vegetables. /Former use/

Insecticide with contact and stomach action. ...Effective against Aphididae, Coccidae, Diaspididae and Margarodidae (at 500-1000 g/ha) in cabbages, citrus and ornamentals; also against Agromyzidae, Cicadellidae, Delphacidae, Ephydridae and Pyralidae (at 600-900 g/ha) in paddy rice; against Coleoptera (at 1.2 kg/ha) in turf and trees; against Noctuidae and Pieridae (at 500-1000 g/ha) in pome fruit, citrus fruit and vegetables. /Former use/

Tradename: 'Karphos' (Sankyo)

Tech. is >93%.