Tebuthiuron

228.31500

228.31

251-793-7

E5OX6GM11E

3077

DTXSID3024316

Colorless solid|Gray to dark brown pellet

2934999090

86.36000

2.00210

Tebuthiuron appears as colorless odorless crystals. Non corrosive. Used as an herbicide.

1.186g/cm3

161.5-164 °C

1.555

In water, 2.5X10+3 mg/L at 25 deg C

0-6ºC

3.0X10-7 mm Hg at 25 deg C (0.04 mPa, 25 deg C, gas saturation method)

LD50 in mice, rats, rabbits (mg/kg): 579, 644, 286 orally (Todd)

Odorless

1.20e-10 atm-m3/mole|Henry's Law constant = 1.2X10-10 atm-cu m/mol (1.31X10-5 Pa-cu m/mol) at 25 °C

pKa = 1.20

Stable in aqueous media between pH 5 and 9. On hydrolysis, DT50 (25 °C) >64 days (pH 3, 6, and 9).|Dry flowable and wettable powder disperse in water. Pellets are not soluble, but disintegrate in water. Granules not soluble.|Hydroxyl radical reaction rate constant = 3.3X10-12 cu cm/molec-sec at 25 °C (est)

No rapid reaction with air. No rapid reaction with water.

Amides and Imides

A urea, thiadiazole derivative.

Noncorrosive in commercial packaging

UN 3077

3

R22; R50/53

S37-S60-S61

YS4250000

Xn; N

Stable to light.

P301 + P312 + P330

H302-H410

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.

USEPA/Office of Prevention, Pesticides and Toxic Substances; Reregistration Eligibility Decision Document - Tebuthiuron (June 1994). The RED summarizes the risk assessment conclusions and outlines any risk reduction measures necessary for the pesticide to continue to be registered in the U.S.[Available from, as of May 28, 2009: http://www.epa.gov/pesticides/reregistration/status.htm]|California Environmental Protection Agency/Department of Pesticide Regulation; Toxicology Data Review Summaries.[Available from, as of April 30, 2009: http://www.cdpr.ca.gov/docs/risk/toxsums/toxsumlist.htm]|USEPA; Health Advisories for 50 Pesticides p.818 (1988) PB88-245931

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]: Some may burn but none ignite readily. Containers may explode when heated. Some may be transported hot. For UN3508, be aware of possible short circuiting as this product is transported in a charged state. (ERG, 2016)

|Warning|H302: Harmful if swallowed [Warning Acute toxicity, oral]|P264, P270, P273, P301+P312, P330, P391, and P501|H302 (100%): Harmful if swallowed [Warning Acute toxicity, oral]|P260, P264, P270, P273, P280, P301+P312, P305+P351+P338, P314, P330, P337+P313, P391, and P501|Aggregated GHS information provided by 187 companies from 3 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.|Danger|H315: Causes skin irritation [Warning Skin corrosion/irritation]|P201, P202, P260, P261, P264, P270, P271, P272, P280, P281, P302+P352, P304+P340, P305+P351+P338, P308+P313, P312, P314, P321, P332+P313, P333+P313, P337+P313, P362, P363, P403+P233, P405, and P501

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]: SMALL FIRE: Dry chemical, CO2, water spray or regular foam. LARGE FIRE: Water spray, fog or regular foam. Do not scatter spilled material with high-pressure water streams. Move containers from fire area if you can do it without risk. Dike fire-control water for later disposal. FIRE INVOLVING TANKS: Cool containers with flooding quantities of water until well after fire is out. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks engulfed in fire. (ERG, 2016)

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]: As an immediate precautionary measure, isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids. SPILL: Increase, in the downwind direction, as necessary, the isolation distance shown above. FIRE: If tank, rail car or tank truck is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2016)

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]: Do not touch or walk through spilled material. Stop leak if you can do it without risk. Prevent dust cloud. Avoid inhalation of asbestos dust. SMALL DRY SPILL: With clean shovel, place material into clean, dry container and cover loosely; move containers from spill area. SMALL SPILL: Pick up with sand or other non-combustible absorbent material and place into containers for later disposal. LARGE SPILL: Dike far ahead of liquid spill for later disposal. Cover powder spill with plastic sheet or tarp to minimize spreading. Prevent entry into waterways, sewers, basements or confined areas. (ERG, 2016)

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]: Wear positive pressure self-contained breathing apparatus (SCBA). Structural firefighters' protective clothing will only provide limited protection. (ERG, 2016)|The following PPE is the minimum PPE required for all persons handling products containing tebuthiuron: long sleeved shirt, long pants, shoes and socks. In additions, if the tebuthiuron end-use products are in Toxicity Category I, II, or III for acute dermal toxicity or skin irritation potential, chemical-resistant or waterproof gloves (whichever is appropriate) are required.|Long-sleeved shirt and long pants. Protective eyewear. Waterproof gloves. Waterproof boots.

Not flammable

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 POTW is acceptable only after review by the governing authority. 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 meet Hazardous Material Criteria for disposal.

In case of spills, collect, cover or incorporate granules/pellets spilled on the soil surfaces to prevent contamination to water.|Do not apply to water, or to areas where surface water is present or to intertidal areas below the mean high water mark. Do not contaminate water when disposing of equipment washwaters or rinsate.|For several good reasons, .... herbicides ... should be handled and applied only with full attention to safety measures that minimize personal contact. Many formulations contain adjuvants (stabilizers, penetrants, surfactants) that may have significant irritating and toxic effects. A number of premixed formulations contain two or more active ingredients; the companion pesticides may be more toxic than the principal herbicide. Good hygienic practice should not be disregarded just because a pesticide is reported to have a high LD50 in laboratory rodents.|Keep away from children. Do not reuse empty container.|Harmful if swallowed. Avoid contact with skin, eyes, or clothing.In case of contact, flush with water. Avoid breathing mist or dust. Do not apply, drain, or flush equipment on or near desirable trees or other plants, or on areas to which their roots extend. Do not contaminate any body of water.

The highest concn of tebuthiuron in runoff water ranged from 40 to 91 ug/L in the first significant rain event after tebuthiuron application to a rangeland watershed in Arizona. Concns in runoff after subsequent rain events were much lower(1). On Texas blacklands prairie, tebuthiuron in surface runoff following spray and pellet application could be as high as 12 and 3 ppm, respectively if heavy rainfall occurred immediately after application(2). However, if rainfall occurred 2 mo after application, <1 ppm tebuthiuron occurred in runoff. The concn of tebuthiuron in runoff 3 mo after application was usually <0.05 ppm(2).

SOIL: The amount of tebuthiuron, applied at 2.24 kg/ha as broadcast spray and pellets in the upper 15 cm of Texas Blacklands Prairie was 0.30 kg/ha and not detectable, 0.22 and 0.09 kg/ha and 0.120 and 0.56 kg/ha, 1 mo, 3 mo and 6 mo after application, respectively(1).

LD50 Rat oral 644 mg/kg|LD50 Mouse oral 579 mg/kg|LD50 Rabbit oral 286 mg/kg|LD0 Dog oral > 500 mg/kg|For more Non-Human Toxicity Values (Complete) data for TEBUTHIURON (12 total), please visit the HSDB record page.

Tebuthiuron's production may result in its release to the environment through various waste streams; its use as a herbicide(1) will result in its direct release to the environment(SRC).

TERRESTRIAL FATE: Based on a classification scheme(1), Koc values of 130(2), 2.70 to 84.1(3), and 80(4) indicate that tebuthiuron is expected to have very high to high mobility in soil(SRC). Volatilization of tebuthiuron from moist soil surfaces is not expected to be an important fate process(SRC) given a Henry's Law constant of 1.2X10-10 atm-cu m/mole(5). Tebuthiuron is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 3.0X10-7 mm Hg at 25 °C(6). A half-life of 35.4 months in a sandy loam soil at 75% field moisture capacity(7) suggests that biodegradation is not an important environmental fate process in soil(SRC).|TERRESTRIAL FATE: In field experiments in Arizona in which tebuthiuron (0.84 kg/ha) was applied to a rangeland watershed (slope 3%, soil OC about 1.05%, precipitation 586 mm) in February, 1981, 0.42% and 0.047% was removed in runoff water and suspended sediment in 1981 and 1982, respectively(1). The low removal rate in runoff is believed to be due to the timing of the application relative to rain events. Tebuthiuron moved to a depth of 15 cm in 8 months with 326 mm of precipitation and remained at that depth despite additional precipitation(1). The total amount of tebuthiuron remaining in the test plots after 21 months was 38% of that applied(1). Accordingly, it would take 2.9 to 7.2 years for the tebuthiuron level to fall below the detection limit. The herbicide retained its activity after 21 months. Another investigator found that tebuthiuron moved to 61 cm after 6 months in Houston black clay, soil typical of the Blackland Prairie and that the herbicide was still active after 2.5 years(1). In studies in which tebuthiuron was applied to field plots in central Utah as 40% (206 mg) pellets at 0.6 or 1.1 kg/ha, it was found that tebuthiuron moved downward and outward from the point of placement of the pellet(2). Dissipation from the upper 3 cm of soil within 2 cm of the pellet was best explained by a nonlinear expression with the time after placement as the independent variable; after 180, 365, and 730 days the concn in the soil was 53.0, 10.6, and 2.20 ppm, respectively(2). Based on a review of the literature, tebuthiuron exhibits a field half-life of 360 days(3).|TERRESTRIAL FATE: Tebuthiuron has a half life in soil of 12 to 15 months in areas receiving 40 to 60 inches of annual rainfall. The half life is considerably greater in low rainfall areas and in muck and other high organic soils, regardless of rainfall. In field studies, tebuthiuron and its transformation products have seldom been detected below the top 12 inches of soil. Little or no lateral movement has been observed.|TERRESTRIAL FATE: The dissipation and leaching characteristics of the herbicide tebuthiuron, ... were examined in this field study conducted at sites near Live Oak, Florida; Davenport, California; and Mead, Nebraska. The rise and decline of tebuthiuron's major soil metabolite was also followed. The tebuthiuron dissipation half-lives were 383, 806, and 575 days for the Florida, California, and Nebraska sites, respectively. At the California and Nebraska sites, tebuthiuron reached a maximum depth of approximately 69 and 84 cm, respectively. In the sand soil at the Florida site, tebuthiuron leached past the maximum sampling depth of 183 cm. The major soil metabolite reached a concentration of 23% of applied and leached to a maximum depth of approximately 38 cm at the California site. At the other sites, the metabolite did not exceed 9% of applied and leached no deeper than approximately 23 cm.|For more Environmental Fate (Complete) data for TEBUTHIURON (6 total), please visit the HSDB record page.

The rate constant for the vapor-phase reaction of tebuthiuron with photochemically-produced hydroxyl radicals has been estimated as 3.3X10-12 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 5 days at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). Tebuthiuron is stable in aqueous media between pH 5 and 9. The hydrolysis half-life at 25 °C is greater than 64 days at pH 3, 6, and 9(2). Data indicate that photodegradation of tebuthiuron on soil may occur slowly but that this is not likely to be a route of dissipation(3). The compound did not degrade in sterile aqueous buffered (pH 5) solutions which were continuously irradiated for 33 days with a xenon light source at approximately 25 °C(3). Therefore, direct photolysis by sunlight is not likely to be an important environmental fate process(SRC).|Tebuthiuron is resistant to hydrolysis. (14)C-Tebuthiuron at 10 and 100 ppm did not degrade during 64 days of incubation in sterile aqueous solutions at pH 3, 6 and 9 in the dark at 25 °C.|After 23 days of irradiation with artificial light (20 W black light), tebuthiuron accounted for 87 to 89% of the applied radioactivity in deionized (pH 7.1) and natural (pH 8.1) water treated with thiadiazole ring labeled (14)C-tebuthiuron at 25 ppm. After 15 days of irradiation with a black light or a sunlamp, tebuthiuron accounted for approx 82 and 53%, respectively, of the applied cmpd in natural water treated with (14)C-tebuthiuron at 2.5 ppm.

An estimated BCF of 7 was calculated in fish for tebuthiuron(SRC), using a log Kow of 1.79(1) and a regression-derived equation(2). According to a classification scheme(3), this BCF suggests the potential for bioconcentration in aquatic organisms is low(SRC).

67.61 L/kg|Tebuthiuron has a half life in soil of 12 to 15 months in areas receiving 40 to 60 inches annual rainfall. The half life is considerably greater in low rainfall areas and in muck and other high organic soils regardless of rainfall. In field studies, tebuthiuron and its transformation products have seldom been detected below the top 12 inches of soil. Little or no lateral movement has been observed .|For tebuthiuron, Koc values of 130(1), 2.70 to 84.1(6), and 80(2) have been reported. According to a suggested classification scheme(3), these Koc values suggest that tebuthiuron has high to very high mobility in soil(SRC). The principal route of dissipation in the environment is mobility in soil(4). The soil/water distribution constant of tebuthiuron in Eufaula sand (% OC not reported) was 0.2(5). Adsorption of tebuthiuron to soil increases with the organic carbon and clay content of the soil. Sorption Kd values for tebuthiuron on six acid, low base saturated sands as a function of depth ranged from 0.002 to 3.6 L/kg with the greatest sorption on soils from the surface 0-5 cm depth and the least on soils from depths >65 cm; sorption was shown to correlate to soil organic carbon(6). A mean Kd value of 1.63 based on 9 samples has been also reported(7).|In field studies conducted at five sites in north-central Arizona, tebuthiuron was primarily found in the upper 30 cm of soil during the first five years after application(1). After 9 years, 55-73% of the tebuthiuron was at depths between 30 and 90 cm(1). Small amounts of tebuthiuron were found as deep as 105 cm 6 to 9 years after application and small amounts were found in the upper 7 cm 10 years after application(1). Long-term leaching was not affected by application rate and leaching was not appreciably different in clay or loam soils(1). Lysimeter experiments were performed with intact soil columns from several upper Great Lakes sites (acidic, sandy soil) in which 440 mm of water was applied over a 130-day study period(2). Tebuthiuron leached to the 150-cm level in two lysimeters after 66 days and was detected at that level in 12 of 36 treated lysimeters. No tebuthiuron reached the 150-cm level in soils from two of the six sites where the pH of the surface 40 cm of soil was 4.7 and the base saturation averaged 22%; small amounts of tebuthiuron were recovered from four more acidic sites where the pH averaged 4.3 and the base saturation was <6%. Concns of tebuthiuron in the surface layers of soil were nearly five times that at the 150 cm level indicating that most of the herbicide remains in the upper profiles after the first growing season. In cited studies(2), the distribution of tebuthiuron applied at 8.8 kg/ha to a boreal podzol was distributed, 310 days post treatment, 98.6% in the surface 8 cm and 1.4% in upper B horizon; in a semi-arid rangeland site, for the first five years post-treatment most of the tebuthiuron remained in the surface 60 cm of soil, mainly in the 7-30 cm zone, and from 9-11 years it was mainly in the 60-90 cm zone(2).|When C14-tebuthiuron was leached through a 35-cm column filled with Lakeland sand soil (1.0% organic matter, pH 4.7) under saturated flow conditions (51 cm of water applied over 3 hr), saturated-unsaturated flow (10.2 cm/day once every 8 days over 40 days), and unsaturated flow (1.27 cm/day for 40 days), 81.2%, 8.4%, and 2.5% of tebuthiuron was found in the leachate, respectively(1). Tebuthiuron was uniformly distributed in the soil in all three systems. Under the unsaturated flow conditions, 0.9%, 0.7%, and 40.9% of the applied tebuthiuron was in the leachate in columns filled with Portsmouth sandy loam (4.4% organic matter, pH 5.4), Rains silt loam (1.7% organic matter, pH 6.0), and Davidson clay (1.3% organic matter, pH 5.6), respectively(1). The high amount of leaching in the Davidson clay is related to the high flow rate through this fine textured soil, compared with the relatively slow flow rates in the other, coarse-textured soils. Additionally, about half of the applied tebuthiuron was retained in the upper 5 cm of the Portsmouth and Rains soil, while only 2.4% was retained in the 0-5 cm depth of the Davidson clay.|Ring labeled (14)C-tebuthiuron was very mobile (>94% of that was found in the leachate) in a 12 inch column of Lakeland fine sand soil leached with 20 inches of water. It was mobile in columns of loamy sand (approx 73% at 6 to 10 inches), loam (approx 84% at 1 to 8 inches) and muck (100% at 0 to 4 inches) soils leached with 4 to 8 inches of water.

The Henry's Law constant for tebuthiuron is 1.2X10-10 atm-cu m/mole(1). This Henry's Law constant indicates that tebuthiuron is expected to be essentially nonvolatile from water surfaces(2). Tebuthiuron is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 3.0X10-7 mm Hg(3).|Tests indicate that loss due to photodecomposition and volatilization is negligible.

GROUNDWATER: Groundwater monitoring results for tebuthiuron according to EPA's compilation of groundwater studies are (state, years, number of wells sampled, number of positive wells, concn): California, 1989, 29, 1, 20.7-22.1 ug/L; Mississippi, 1989-90, 120, 0, nd; Oklahoma, 1986, 1, 0, nd; Texas, 1975, 2, 2, trace - 380.0 ug/L; Washington, 1988, 81, 0, nd(1). In Ontario, 1 of 7 wells and 3 of 8 wells with suspected contamination resulting from runoff/wind drift and spills between 1979 and 1984, contained tebuthiuron above 0.1 ug/L(2). In two cases where spills occurred, the tebuthiuron residues were 125 ug/L 6 months after the spill and 921 ug/L 23 months after the spill(2). Sampling of 20 springs and nine wells in the Ozark Plateaus Province and in to shallow domestic wells and 50 springs in the Springfield Plateau of Arkansas, Kansas, Missouri, and Oklahoma was conducted from April through September 1993; tebuthiuron was detected in 7 samples with a concentration range of 0.005 to 0.23 ug/L(3). Tebuthiuron was detected in 20% of samples from an unconsolidated aquifer beneath Denver, Colorado (South Platte River Basin) sampled in 1993, with a maximum concn of 0.079 ug/L (detection limit 0.015 ug/L)(4). Tebuthiuron was detected in 2.2%, 4.6%, 2.6%, and 4.5% of groundwater samples from areas used for corn and alfalfa, corn, pasture, and in urban settings, respectively, with a maximum concn of 0.35 ug/L, detection limit = 0.01 ug/L; sampling was conducted during 1993-1995 in 20 major hydrologic basins of the United States(5).|SURFACE WATER: Results of a survey conducted from April 1993 through April 1994 of two tributary streams of the South Platte River, one in a small agricultural area and one in a small urban area of Colorado were reported. Tebuthiuron was detected in 5% of agricultural samples at a <0.015 median, max 0.047 (detection limit = 0.015 ug/L; and was detected in 20% of urban samples, <0.015 ug/L median, max of 0.061 ug/L(1). The compound was detected in 5 of 98 samples, <0.01 and 0.014 ug/L minimum and maximum, respectively, (detection limit 0.01 ug/L, from the Yakima River Basin, Washington; samples were collected from 1999 to 2000, from 34 sites throughout the basin in August 1999, and also weekly and monthly samples from May 1999 through January 2000 at three of the sites(2).|RAIN/SNOW/FOG: Tebuthiuron was not detected in rain samples collected from April through September 1995 in Jackson (urban) and Rolling Fork (agricultural) Mississippi(1).

Occupational exposure to tebuthiuron may occur through inhalation and dermal contact with this compound at workplaces where tebuthiuron is produced or used. Monitoring data indicate that the general population may be exposed to tebuthiuron via ingestion of contaminated well water in agricultural regions where tebuthiuron is applied. (SRC)

Tebuthiuron technical (99.6% pure) at 10 mg/kg (containing 5% w/w (14C)-EL103) was administered to ICR mice, Harlan rats, Dutch-belted rabbits and mallards by gavage (vehicle = water or 5% (w/v) acacia) and to beagle dogs by gelatin capsule. Bluegills received 25 ppm EL103 (plus 0.01% w/w (14C)-EL103) in the aquarium water. Tebuthiuron was readily absorbed by mice, rats, rabbits, dogs and ducks. It was extensively metabolized (with differences in proportions of metabolites produced) and metabolites were excreted in urine of mice, rats, rabbits and dogs and in urine/feces mix in ducks. By 96 hours, approximately 3% of metabolites were in feces of rats, dogs, rabbits and ducks, with 30% detected in feces of mice. ... Tebuthiruon did not accumulate (nor did metabolites) in tissues of any species tested.|Radiolabeled tebuthiuron was administered to male and female ICR mice, Harlan rats, Dutch-Belted rabbits and beagle dogs at a dose of 10 mg/kg by gavage. Elimination of radioactivity was virtually complete within 72 hours and recovery values at 96 hours were 96.3, 94.5, 94.3 and 95.7% in the mouse, rat, rabbit and dog, respectively. In the rats, rabbits and dogs, the radioactivity was excreted almost exclusively in the urine. In the mice, 30% of the radioactivity was excreted in the feces.|/It has been/ reported that 94 to 96% of a single oral dose of tebuthiuron (10 mg/kg) was excreted in the urine of rats, rabbits and dogs. In mice, 66% was excreted in the urine, and 30% in the feces. These data indicate that tebuthiuron was well absorbed (about 70 to 96%) from the gastrointestinal tract.|... Tebuthiuron /was administered/ in the diet to 20 pregnant Wistar rats at levels of 100 or 200 ppm for 6 days prior to delivery. Forty-eight hr after delivery, radiolabelled tebuthiuron was reintroduced into the diet at the same levels as before. Radioactive label was detected in the milk at mean levels of 2.7 and 6.2 ppm for the 100 and 200 ppm groups, respectively.|For more Absorption, Distribution and Excretion (Complete) data for TEBUTHIURON (7 total), please visit the HSDB record page.

Orally dosed tebuthiuron was readily absorbed in mice, rats, rabbits, dogs, and ducks. The compound was extensively metabolized and the metabolites were rapidly excreted in the urine of mice, rats, rabbits, and dogs and in the mixture of urine and feces in ducks. The major metabolites of tebuthiuron were formed by N-demethylation of the substituted urea side chain in each species examined, including fish. Oxidation of the dimethylethyl group occurred in mice, rats, dogs, rabbits, and ducks. The N-demethylation reaction at the 3-position of the urea preceded through an N-hydroxymethyl intermediate. No accumulation of tebuthiuron or its metabolites was observed in the animals, a finding consistent with the low order of toxicity observed in other studies.|In plants, the principal metabolic pathways involve N-demethylation and hydroxylation of the tert-butyl side chain.|Tebuthiuron was administered by gavage to male and female ICR mice, Harlan rats, Dutch-Belted rabbits and beagle dogs at a dose of 10 mg/kg. Examination of urine extracts by thin-layer chromatography showed the presence of eight radioactively labeled metabolites in rat, rabbit and dog urine and seven in mouse urine. Small amt of unchanged tebuthiuron also were detected in each case (except the mouse). The major metabolites were formed by N-demethylation of the substituted urea side chain in each species examined. Oxidation of the dimethylethyl group also occurred in all species examined.|In a metabolism study male and female Fischer 344 rats were dose with (14)C-tebuthiuron at a single low oral dose (10 mg/kg), a repeated low oral dose (10 mg/kg x 14 days), or a single high dose (100 mg/kg) ... From HPLC and mass spectral analysis of urine samples, 6 metabolites of tebuthiuron were identified. The major metabolite was identified as /N-[5-(2-hyroxy-1, 1-dimethylethyl)-1, 3, 4-thiadiazol-2-yl]-N'-hydroxymethyl-N-methyl urea/ and/or/N-[5-(2-hydroxy-1, 1-dimethylethyl)-1, 3, 4-thiadiazol-2-yl]-N-methylurea/, both hydroxylated metabolites of tebuthiuron. This metabolite composed between 39.6-60.3% of the administered dose in 0-24 hour urine of male and female rats. The second most abundant metabolite was identified as metabolite /N-[5-(1, 1-dimethylethyl)-1, 3, 4-thiadiazol-2-yl) urea/ of tebuthiuron. This comprised between 9-15% of the administered dose in 0-24 hour urine of low dose rats, and between 55.6% and 57.3% of the administered dose for male and female rats, respectively. Two other metabolites identified, (/N-[5-(1, 1-dimethylethyl)-1, 3, 4-thiadiazol-2-yl]-N-methylurea/)/(/ N-[5-(1, 1-dimethylethyl)- 1, 3, 4-thiadiazol-2-yl]-N'-hydroxymethyl-N-methylurea/) and /N-[5-(2-hydroxy-1, 1-dimethylethyl)-1, 3, 4-thiadiazol-2-yl]-N, N'-dimethylurea/, comprised between 2-10% of the administered dose in male and female 0-24 hour urine. Feces contained minor amounts of / N-[5-(2-hydroxy-1, 1-dimethylethyl)-1, 3, 4-thiadiazol-2-yl]-N-methylurea / and / N-[5-(2-hydroxy-1, 1-dimethylethyl)- 1, 3, 4-thiadiazol-2-yl]-N'-hydroxymethyl-N-methylurea/, accounting for an average of 3.5% of the administered dose.

Phytotoxicity symptoms suggest that tebuthiruon inhibits photosynthesis.

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]: Inhalation of material may be harmful. Contact may cause burns to skin and eyes. Inhalation of Asbestos dust may have a damaging effect on the lungs. Fire may produce irritating, corrosive and/or toxic gases. Some liquids produce vapors that may cause dizziness or suffocation. Runoff from fire control may cause pollution. (ERG, 2016)

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]: Ensure that medical personnel are aware of the material(s) involved and take precautions to protect themselves. Move victim to fresh air. Call 911 or emergency medical service. Give artificial respiration if victim is not breathing. Administer oxygen if breathing is difficult. Remove and isolate contaminated clothing and shoes. In case of contact with substance, immediately flush skin or eyes with running water for at least 20 minutes. (ERG, 2016)

Skin contamination should be treated promptly by washing with soap and water. Contamination of the eyes should be treated immediately by prolonged flushing of the eyes with large amounts of clean water. If dermal or ocular irritation persists, medical attention should be obtained without delay. /Other Herbicides/|Activated charcoal is probably effective in limiting irritant effects and reducing absorption of most or all of these herbicides. /Other herbicides/|If serious dehydration and electrolyte depletion have occurred as a result of vomiting and diarrhea, monitor blood electrolytes and and fluid balance and administer intravenous infusions of glucose, normal saline ringer's solution, or ringer's lactate to restore extracellular fluid volume and electrolytes. Follow this with oral nutrients as soon as fluids can be retained. Fluids serve to support excretion of the toxicants. Supportive measures are ordinarily sufficient for successful management of excessive exposures to these herbicides. /Other Herbicides/|/SRP:/ Immediate first aid: Ensure that adequate decontamination has been carried out. If patient is not breathing, start artificial respiration, preferably with a demand valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR if necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on the left side (head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Poisons A and B/|For more Antidote and Emergency Treatment (Complete) data for TEBUTHIURON (6 total), please visit the HSDB record page.

1-(5-tert-butyl-1,3,4-thiadiazol-2-yl)-1,3- dimethylurea

The estimated lbs of active ingredient of tebuthrian used per year in 1987/1989 was: Kansas 385160; Oklahoma 222430. Pasture land was treated with 607,590 lbs/active ingredient/yr.

Single active ingredient: 3.0 and 5.0% granular; 20.0 and 40.0% pelleted/tableted; 80.0% wettable powder; 85.0% water dispersible granules (dry flowable); and 95.0% technical grade/solid.|Multiple active ingredient: 1.0% granular (tebuthiuron plus one other active ingredient); 2.0% granular (tebuthiuron plus one other active ingredient); 2.0% granular (tebuthiuron plus another active ingredient).|Mixtures include: terbuthiuron + 2,4-D + picloram|Pellets, wettable powder, concentrate suspension.|For more Formulations/Preparations (Complete) data for TEBUTHIURON (14 total), please visit the HSDB record page.

The WHO Recommended Classification of Pesticides by Hazard identifies Tebuthiuron (technical grade) as Class III: slightly hazardous; Main Use: Herbicide.|Brush Bullet, Graslan, Perflan are discontinued names.

Method: USGS-NWQL O-2060-01; Procedure: high performance liquid chromatography-mass spectrometry; Analyte: tebuthiuron; Matrix: water; Detection Limit: 0.0031 ug/L.|Method: USGS-NWQL O-1126-95; Procedure: gas chromatography-mass spectrometry with select-ion monitoring; Analyte: tebuthiuron; Matrix: natural water; Detection Limit: 0.015 ug/L.|Method: EPA-TSC/NERL 507; Procedure: gas chromatography with a nitrogen-phosphorus detector; Analyte: tebuthiuron; Matrix: ground water and finished drinking water; Detection Limit: 0.58 ug/L.|Method: EPA-OGWDW/TSC 532; Procedure: high performance liquid chromatography with an ultraviolet/visible (UV/Vis) detector; Analyte: tebuthiuron; Matrix: drinking waters; Detection Limit: 0.046 ug/L.|For more Analytic Laboratory Methods (Complete) data for TEBUTHIURON (8 total), please visit the HSDB record page.

Agrochemicals -> Herbicides