O,O-Diethyl-O-1-phenyl-1,2,4-triazol-3-ylthio-phosphat

This is an organophosphate pesticide. Keep unnecessary people away; isolate hazard area and deny entry. Stay upwind; keep out of low areas. Ventilate closed spaces before entering them. Wear positive pressure breathing apparatus and special protective clothing. Remove and isolate contaminated clothing at the site. Move container from fire area if you can do it without risk. Fight fire from maximum distance. Dike fire control water for later disposal; do not scatter the material.

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]

Pesticides of any degree of toxicity should be transported in containers which are clearly labelled, leak-proof and not easily damaged. They should never be transported beside or above any type of food, and all spillages should be immediately reported. Any foodstuffs transported in the same compartment as a pesticide may thus be held, pending examination to ensure that it has not been in any way contaminated. ... Pesticides of moderate or higher hazard should be so stored that only authorized persons can have access to them. It is particularly important that children should be excluded from any contact with pesticide concentrates or residues. Spillages often occur in storage and repacking rooms and must be cleaned up with care. Rooms used for storage only should be soundly constructed and fitted with secure locks. Floors should be kept clear and the pesticides clearly identified. If repacking is carried out in storage rooms, adequate light should be available; floors should be impervious and sound; washing facilities should be available ... /Pesticides/

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity 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 and plant life; and conformance with environmental and public health regulations.

SRP: Wastewater from contaminant suppression, cleaning of protective clothing/equipment, or contaminated sites should be contained and evaluated for subject chemical or decomposition product concentrations. Concentrations shall be lower than applicable environmental discharge or disposal criteria. Alternatively, pretreatment and/or discharge to a permitted wastewater treatment facility is acceptable only after review by the governing authority and assurance that "pass through" violations will not occur. Due consideration shall be given to remediation worker exposure (inhalation, dermal and ingestion) as well as fate during treatment, transfer and disposal. If it is not practicable to manage the chemical in this fashion, it must be evaluated in accordance with EPA 40 CFR Part 261, specifically Subpart B, in order to determine the appropriate local, state and federal requirements for disposal.

SRP: Contaminated protective clothing should be segregated in such a manner so that there is no direct personal contact by personnel who handle, dispose, or clean the clothing. The completeness of the cleaning procedures should be considered before the decontaminated protective clothing is returned for reuse by the workers. Contaminated clothing should not be taken home at the end of shift, but should remain at employee's place of work for cleaning.

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, NOS/

Personnel protection: Keep upwind. Wear appropriate chemical protective gloves, boots and goggles. Do not handle broken packages unless wearing appropriate personal protective equipment. Wear positive pressure self-contained breathing apparatus when fighting fires involving this material. /Organophosphorus pesticides, liquid, NOS/

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

For more Preventive Measures (Complete) data for TRIAZOPHOS (11 total), please visit the HSDB record page.

0.25 [mg/m3]

2.8 [mg/m3]

12 [mg/m3]

For emergency situations, wear a positive pressure, pressure-demand, full facepiece self-contained breathing apparatus (SCBA) or pressure- demand supplied air respirator with escape SCBA and a fully-encapsulating, chemical resistant suit. (EPA, 1998)

Workers ... must be given personal protective equipment comprising overalls made of a tight fabric or polyvinyl chloride, gloves & rubber boots. They must wear a respirator with an activated-carbon gas filter cartridge affording protection for a determined number of hours. The eyes should be protected by goggles. /Organophosphorus pesticides/

TERRESTRIAL FATE: Based on a classification scheme(1), a Koc value of 355(2), indicates that triazophos is expected to have moderate mobility in soil(SRC). Volatilization of triazophos from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 3.1X10-8 atm-cu m/mole(SRC), based upon its vapor pressure, 2.9X10-6 mm Hg(3), and water solubility, 39 mg/L(3). Triazophos is not expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(3). Triazophos, incubated at 22 °C for 64 or 84 days, had half-lives of 17-23 days in five soils, in three soils half-lives were 39-46 days, and in one soil an extrapolated half-life of 87 days(4). Triazophos, incubated at 27 °C in a clay loam soil and in a loam soil, had half-lives of 2 and 5 days, respectively(4).

AQUATIC FATE: Based on a classification scheme(1), a Koc value of 355(2), indicates that triazophos 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 3.1X10-8 atm-cu m/mole(SRC), derived from its vapor pressure, 2.9X10-6 mm Hg(4), and water solubility, 39 mg/L(4). According to a classification scheme(5), an estimated BCF of 74(SRC), from a log Kow of 3.34(4) and a regression-derived equation(6), suggests the potential for bioconcentration in aquatic organisms is moderate(SRC). Hydrolysis half-lives of 30-250 days were measured for triazophos in water at 25 °C(7). Half-lives of <35 days were measured for triazophos both in water and in a water:sediment slurry(7). Triazophos had a measured half-life of 41 days in river water (pH 7.3 and 22 °C); a half-life of 47 days was measured in filtered river water at the same pH and temperature(8). A half-life of 27 days was measured in sea water (pH 8.1 and 22 °C) for triazophos(8). No distinction was made between losses due to biodegradation, hydrolysis, adsorption, or photolysis(8). Photodegradation half-lives of 21 days and 67 days were measured for river water and sea water, respectively(8); however, as this experiment was conducted in an open system, other factors may have had an effect(8).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), triazophos, which has a vapor pressure of 2.9X10-6 mm Hg at 30 °C(2), will exist in both the vapor and particulate phases in the ambient atmosphere. Vapor-phase triazophos 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 4 hours(SRC), calculated from its rate constant of 9.5X10-11 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). Particulate-phase triazophos may be removed from the air by wet or dry deposition(SRC). Triazophos does not contain chromophores that absorb at wavelengths >290 nm(4) and, therefore, is not expected to be susceptible to direct photolysis by sunlight(SRC).

Triazophos degradation was studied in nine soils. In two different standard German soils, the half-life was calculated to be about 18 days and about 87 days. In nearly all soils, three unidentified cmpds and traces of the hydroxytriazole occurred rapidly and in amounts of 1-6% of the initial radioactivity. 14-CO2 was also recovered.

Triazophos was detected, at unreported concentrations, during a 1978-1982(1) and a 1983-1986(2) survey of US domestic and import commodities. Triazophos was detected in six of 10 unprocessed eggplant samples and in one of 10 processed eggplant samples at 8.8 to 27.5 and 6.2 ppb, respectively, in samples taken from Alexandria City, Egypt from June 1997 to August 1998(3). Triazophos was undetected (detection limit 0.2 ppb) in 30 tomato, 20 cucumber, 18 potato, 12 apple, 20 grape and 12 orange processed and unprocessed samples taken in the same survey(3). Triazophos was analyzed in 397 samples collected in eight local markets from six Egyptian governorates (Cairo, Giza, Qualubiya, Beni Suef, Minufiya and Ismailia) in 1995 and was not detected in tomato, cabbage, cauliflower, carrot, courgette, cucumber, eggplant, green beans, green peas, lettuce, onion, pepper, apple, cantaloupe, grape, guava, mango, orange, peach or strawberry(4). Triazophos was also analyzed in 1579 samples collected in the same Egyptian governorates in 1996 and was not detected in cabbage, grape leaf, lettuce, melokhia, spinach, watercress, artichoke, broad bean, cauliflower, cantaloupe, cucumber, eggplant, green beans, green peas, okra, onion, pepper, squash, carrot, sweet potato, taro, banana, fig, lemon, lime, mango, peach, pear, plum, or pomegranate(5).

Triazophos was not detected in grapefruit, lemon, mandarin/clementine, orange, apple, pear, quince, apricot, cherries, peach, nectarine, plum, grape, strawberry, blackberry, hip, boysenberry, elderberry, raspberry, rowanberry, bilberry, red and black current, gooseberry, banana, fig, kiwi, pomegranate, beetroot, carrot, celeriac, horseradish, parsnip, parsley root, radish, garlic, onion, spring onion, tomato, pepper, eggplant, cucumber, melon, watermelon, squash, sweet corn, broccoli, cauliflower, Brussel sprout, white, red, spring, Oxheart or Chinese cabbage, kale, lettuce, spinach, chive, dill, marjoram, oregano, parsley, rosemary, thyme, bean, pea, celery, leek, rhubarb, mushroom, sunflower seed or potato in the 1995-1996 Danish national pesticide monitoring program(1). A market basket survey of produce conducted in Trinidad, West Indies from Oct 1996 to May 1997 reported that triazophos was detected in celery at 1.74 to 40.20 mg/kg, in lettuce at 4.88 mg/kg and in pak-choi at 0.16 to 4.74 mg/kg(2). Triazophos was not detected in sweet pepper, cabbage, cauliflower, cucumber, spinach, chive tomato, hot pepper, cilantro, okra, watercress, eggplant, sorrel fruit or green beans(2). Triazophos was not detected (detection limit 1 ug/kg) in 298 raw milk samples obtained directly from tank trucks during delivery at nine Italian dairy plants, sampling took place Oct 2004, Jan and May 2005(3).

In plants to which triazphos had been applied, the residues at harvest consisted mainly of unchanged triazophos plus 1-phenyl-3-hydroxy-1,2,4-triazole (1/5 of the total residue), and traces of the P=O analog of triazophos. Fifteen wk after application of triazophos to cotton, residues consisted of triazophos (0.02 ppm), 1-phenyl-3-hydroxy-1,2,4-triazole (0.01 ppm) and an unidentified cmpd (0.01 ppm). The latter was probably a desethyl analog. Similar results were obtained with beans and rice.

Triazophos levels in wheat grain, and in leaf and stem material were 0.187-1.865, and 3.168-44.506 mg/kg, respectively, in 2003 and 0.023-1.396, and 2.040-12.909, respectively, in 2004(1).

Workers handling & applying pesticides must undergo an annual medical examination at the beginning of each agricultural season. Contraindications for work with OPP /organophosphorus pesticides/ are organic diseases of the central nervous system, mental disorders & epilepsy, pronounced endocrine & vegetative disorders, pulmonary tuberculosis, bronchial asthma, chronic respiratory diseases, cardiovascular diseases & circulatory disorders, gastrointestinal diseases (peptic ulcer), gastroenterocolitis, diseases of liver & kidneys, eye diseases (chronic conjunctivitis & keratitis). The blood cholinesterase activity 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 to OPP until this activity is completely restored. Persons with initial signs of indisposition should cease work with pesticides. /Organophosphorus pesticides/

The Koc of triazophos has been reported to be 355(1). According to a classification scheme(2), this Koc value suggests that triazophos is expected to have moderate mobility in soil(SRC). S-type adsorption isotherms were determined for triazophos in two types of soil, a black soil(66.3 meq/100 g soil; 1.65% organic matter; 109.3 sq m/g soil; 29.7 me/100 g soil) and a red soil (1.35 meq/100 g soil; 1.24% organic matter; 23.9 sq m/g soil; 10.4 me/100 g soil)(3). The black soil had higher adsorptive capacity than the red soil; adsorptive strength was greatest for both soils at pH 6-7. Rate constants for the reaction of triazophos with both soils varied from 0.0227-0.0246/min(3). The addition of a 0.2 m water layer over two days to soil columns containing triazophos resulted in no leaching of this compound from the columns(4).

/HUMAN EXPOSURE STUDIES/ In ... a preliminary study, triazophos (purity, 90%) initially prepared in ethanol and then diluted with tap water to provide single nominal doses of 0.012 and 0.062 mg/kg bw per day in a dose volume of approximately 100 mL was administered sequentially to one 41-year-old man orally. The lower dose was administered on day 1 and the higher dose on days 2, 3 and 4, followed by a 7-day recovery period. Blood samples for determination of plasma and erythrocyte cholinesterase activities by a modification of the Ellman technique, were taken from the finger tip before dosing on all treatment days, 0.5, 1 and 2 hr after dosing on days 1 and 2, and 2 and 5 hr after dosing on days 3 and 4. Samples were also taken on recovery days 3 and 7. No apparent change in plasma cholinesterase activity was found on days 1 and 2, but decreases estimated (because of an uncertain baseline) at 20% and up to 34% were observed on days 3 and 4, respectively. Some residual depression by 21% and 14% was found on days 3 and 7 of the recovery period, respectively. Treatment had no apparent effect on erythrocyte cholinesterase activity. The man experienced headache for 3 days from day 2 of dosing to day 1 after dosing was stopped, which might have been related to treatment. ...

/HUMAN EXPOSURE STUDIES/ In a larger study, triazophos (purity, 88%), initially prepared in and stored as a dilution in 30% ethanol before dosing, was administered over 3 weeks at a nominal dose of 0.0125 mg/kg bw per day in 150 mL of lime juice to volunteers from the staff of the laboratory at which the study was performed. Lime juice without the test material was given to participants for about 1 week before dosing. The volunteers, described as healthy, were 13 men aged 17-59 years (average, 26 years) and 12 women aged 16-51 years (average, 28 years). They were given the test material only during the five days of the work week, with a break on weekends. They were observed for overt signs of toxicity. After dosing, they were observed for an additional 4 weeks. A medical history was taken before study initiation, and a physical examination and blood and urine analyses were conducted before treatment and after the end of the treatment-free recovery period. Subjects were requested to inform the investigators if they felt unwell. Plasma and erythrocyte cholinesterase activities were measured. Blood samples for measurement of cholinesterase activity were taken three times before dosing, three times during weeks 1 and 2 of dosing, four times during week 3 of dosing and three times during each week of the treatment-free period. A 20% depression in individual plasma or erythrocyte cholinesterase activity relative to the mean value for the individual before dosing was considered grounds for discontinuing dosing. All 25 subjects completed the study. A slight but statistically significant decrease in group mean blood pressure from that before dosing in women and minor alterations in group mean values in either sex for some hematological and clinical chemical parameters were within normal limits for the laboratory and considered not to be related to treatment. About 50% of the women reported urinating more often, with some feeling of urgency during the first week of dosing, which was attributed to psychosocial causes. One man reported feeling tired and listless during the second week of dosing. Although this individual's plasma cholinesterase activity fell to a limit of concern at the end of the week, the attending physician opted to continue dosing. The plasma cholinesterase activity of this individual did not decrease further during the rest of the study. Another man reporting feeling tired and listless during the second and third weeks of dosing and also had headache, sore throat and soreness in the nose and ear. Two women had diarrhea or diarrhea and vomiting during the second week of dosing, causing absence from work. Another man was absent due to gastrointestinal upset during week 4 after dosing. The authors mentioned that gastrointestinal viral-type infections that had affected workers who were not participating in the study might have been a factor in some of the symptoms noted. The plasma cholinesterase activity of two men and one woman dropped rapidly during the first week of treatment, such that dosing was stopped for 6 days. It was re-commenced during treatment week 3, when the enzyme activity rose to levels considered sufficient. Decreased plasma cholinesterase activity at the end of dosing relative to the mean before dosing, by about 20%, was noted in some individuals, whereas little change in plasma cholinesterase activity was seen in others. The activity of some individuals never completely returned to the values before treatment. Erythrocyte cholinesterase activity was not affected, and no statistically significant changes were observed in cholinesterase activity with the methods used. Evaluation of the symptoms reported suggested that they could generally be explained by non-treatment-related factors. ... The NOAEL was 0.0125 mg/kg bw per day.

Releases of CERCLA hazardous substances are subject to the release reporting requirement of CERCLA section 103, codified at 40 CFR part 302, in addition to the requirements of 40 CFR part 355. Triazofos is an extremely hazardous substance (EHS) subject to reporting requirements when stored in amounts in excess of its threshold planning quantity (TPQ) of 500 lbs.

Used as broad spectrum insecticide and acaricide for fruit and cereals; [HSDB]

Not registered with the EPA for use as pesticide in the US; [CAMEO] Banned in the EU for use as a biocide and agricultural insecticide; [eChemPortal: ESIS]

Farming (Pesticides) [Category: Industry]

Acaricide/miticide, insecticide, nematacide.

For aphids, beetles, borers, bugs, foliar-feeding larvae, fruit flies, leafhoppers, leafminers, nematodes, scales, soil insects, thrips, mites and whiteflies in fruits, vegetables, and ornamentals.

Triazophos is produced by reaction of 1-phenyl-3-hydroxy-1H-1,2,4-triazole, suspended in acetone, with diethoxythiophosphoryl chloride in the presence of triethylamine.

Phenylhydrazine + sodium cyanate + formamide + O,O-diethyl phosphorochlorothioate (cyanate addition/condensation/dehydrochlorination)

Emulsifiable concentrate

Premix Partners: Chlorfluazuron; Chlorpyrifos; Deltamethrin.

HOE 2960

Formulation: Emulsifiable concentrates, wettable powders, ultralow-volume liquids, granules.

For more Formulations/Preparations (Complete) data for TRIAZOPHOS (10 total), please visit the HSDB record page.