Chlorfenac

239.48

239.48

201-599-3

8SOV3EP1QG

41931

DTXSID2040284

CRYSTALS FROM BENZENE|COLORLESS SOLID

2916399017

37.3

3.20

1.568

161 °C

353.5ºC at 760 mmHg

167.6ºC

1.4521 (estimate)

200 MG/L WATER @ 28 DEG C; SOL IN MOST ORGANIC SOLVENTS

0-6°C

1.7x10-5 mm Hg at 25 deg C

Oral-Rat LD50: 1780 mg/kg

Combustion produces toxic chloride gas

Henry's Law constant= 1.8x10-8 atm-cu m/mole at 25 °C (est)

pKa= 3.70

It forms water-soluble salts with alkalis.|1.1 Pa @ 100 °C

NON-CORROSIVE

3077

2

51/53-22

61-36-45-26

AJ8750000

N-Xn,N,Xn

The warehouse is ventilated, low temperature and dry; stored and transported separately from food materials

No shelf life limitations. Not harmed by freeze thaw cycles.

P273

H302-H411

|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]|Aggregated GHS information provided by 127 companies from 1 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Nonflammable

Cleaning glassware and spray equipment: Washes clean with water. Standard washing detergent aid may be used.

2,3,6-Trichlorophenylacetic acid was detected in farm field runoff from treated sugarcane plots at 2 to 310 ppb in rain events up to 6 months after application(1).

Residues of 2,3,6-trichlorophenylacetic acid in sediment samples of 0.26 ppm were found 160 days after an initial application of 1.56 ppm to a pond(1).

moderately toxic

LD50 Rat oral 576-1780 mg/kg|LD50 Rabbit percutaneous 1440-3160 mg/kg|LD50 Rabbit dermal > 3160 mg/kg

2,3,6-Trichlorophenylacetic acid is of anthropogenic origin, and it is not known to be produced by natural sources. (SRC)

2,3,6-Trichlorophenylacetic acid was used as both a pre- and post-emergence herbicide to control annual grasses, broad-leaved weeds(1) and to control submerged aquatic weeds(2). Use of 2,3,6-trichlorophenylacetic acid as a herbicide results in direct application to the environment and is, therefore, its primary environmental emission source(SRC).

TERRESTRIAL FATE: OVER A 3 YR PERIOD, HIGHEST CONCN IN LOSS FROM RUNOFF WERE USUALLY ASSOCIATED WITH RAINSTORMS THAT OCCURRED SOON AFTER APPLICATION. MAXIMAL SEASONAL LOSSES WERE 2.90% OF THE APPLIED FENAC|TERRESTRIAL FATE: ... RESISTS DECOMPOSITION IN SOIL MUCH LONGER THAN ... /CHLOROPHENOXACETIC ACIDS/.|TERRESTRIAL FATE: If released to soil, estimated soil adsorption coefficients ranging from 237 to 1311(1) indicate low to moderate mobility for 2,3,6-trichlorophenylacetic acid(SRC) based on a suggested classification scheme(2). Due to its high degree of ionization at environmental pHs, percent organic matter, clay content, and soil pH are also important factors in determining its degree of adsorption(3). An estimated vapor pressure for 2,3,6-trichlorophenylacetic acid of 1.7x10-5 mm Hg at 25 °C(4) and estimated Henry's Law constant of 1.8x10-8 atm-cu m/mole at 25 °C(5) indicate that important. Biodegradation of 2,3,6-trichlorophenylacetic acid in soil under both aerobic and anaerobic conditions is slow based on data from both laboratory(6) and field experiments(7) although it may be subject to enhanced degradation through cometabolic processes(8).|AQUATIC FATE: If released to water, 2,3,6-trichlorophenylacetic acid is expected to persist for long periods of time. No degradation of 2,3,6-trichlorophenylacetic acid was observed when it was incubated with lake water/sediment or activated sludge under aerobic conditions or when incubated with a sandy loam soil in water under anaerobic conditions(1). Biodegradation studies with soil inoculum and added nutrients produced an enhanced removal rate(1) suggesting that cometabolic process may be important(2). Adsorption of 2,3,6-trichlorophenylacetic acid to sediment may be important based on estimated soil adsorption coefficients ranging from 237 to 1311(3) determined from its water solubility, 200 mg/L(4), and octanol/water partition coefficient, 3.20(5). Laboratory studies have indicated rapid adsorption to sediment(1) although pH, percent organic matter, and clay content of sediment may also be important in determining the degree of adsorption due to 2,3,6-trichlorophenylacetic acid's high degress of ionization at environmental pHs(6-7).|For more Environmental Fate (Complete) data for 2,3,6-TRICHLOROPHENYLACETIC ACID (6 total), please visit the HSDB record page.

No loss of 2,3,6-trichlorophenylacetic acid over 42 days was observed in hydrolysis studies performed at pH 5.0, 7.0, and 9.0 at 25 °C(1). Direct photolysis of 2,3,6-trichlorophenylacetic acid at >280 nm for 36 hours resulted in no degradation(1). Indirect photolysis in natural waters, or in the presence of acetone, benzophenone, or humic acid did not occur although significant degradation was observed in the presence of riboflavin phosphate (75% after 24 hrs), methylene blue, and oxygen-free humic acid solution (50% in 6 hrs)(1). Photolysis of 2,3,6-trichlorophenylacetic acid at 254 nm in the presence of riboflavin phosphate produced a mixture of products resulting from decarboxylation, dechlorination, and hydroxylation reactions(1). Indirect photolysis was retarded in acidic solutions(1). Photolysis of the sodium salt of 2,3,6-trichlorophenylacetic acid, wavelength of light not provided, produced 2,5-dichlorobenzyl alcohol as the major product(2).

Experimental bioconcentration factors ranging from 1.6 to 11.6 in bluegills (Lepomis macrochirus) were determined in static tests with a 2,3,6-trichlorophenylacetic acid concentration of 2 ppm(1). Based on an experimental log Kow of 3.20 for 2,3,6-trichlorophenylacetic acid, obtained in 0.1 and 0.5 M HCl(2), and its water solubility, 200 mg/L at 28 °C(3), estimated bioconcentration factors ranging from 31 to 159 can be calculated(SRC) using an appropriate regression equation(4). The magnitude of these values indicate that bioconcentration in fish and aquatic organisms will not be a significant process(SRC).

63.10 L/kg|Experimental soil adsorption coefficients ranging from 0.3 to 667 on four different sediments with percent organic carbon ranging from 0.3 to 54 were observed at pH 6.5; adsorption on organic muck was found to increase at pH 4.5 but not at pH 9(1). Soil pH, especially in the range 5.0-6.7, was described as the most important factor in 2,3,6-trichlorophenylacetic acid mobility(2-3). At neutral or basic pHs, 2,3,6-trichlorophenylacetic acid will exist predominately as the ionized acid and adsorption to soil will driven by ionic interactions between it and the soil while at more acidic pHs hydrophobic processes will predominate(4). Soil TLC experiments using a wide range of soils (Hagerstown silty clay loam, Lakeland sandy loam, Chillium silt loam) produced Rfs ranging from 0.38 to 1.0 indicating that 2,3,6-trichlorophenylacetic acid has a high degree of mobility compared to other pesticides(2-6).|Based on an experimental log Kow of 3.20 for 2,3,6-trichlorophenylacetic acid, obtained in 0.1 and 0.5 M HCl(1), and its water solubility, 280 mg/L at 28 °C(2), estimated soil adsorption coefficients ranging from 159 to 1311 can be calculated using an appropriate regression equation(3). According to a suggested classification scheme(4), these values suggest that 2,3,6-trichlorophenylacetic acid will display moderate to high mobility in soil. A Koc of 170 has been estimated for 2,3,6-trichlorophenylacetic acid based on its heat of solution(5). In a scale on mobility of pesticides in soil ranging from 1, immobile, to 5, highly mobile, 2,3,6-trichlorophenylacetic acid was placed in mobility class 4(6).

An estimated Henry's Law constant of 1.8x10-8 atm-cu m/mole at 25 °C(1) indicates that 2,3,6-trichlorophenylacetic acid will not volatilize from water and moist soil to the atmosphere(2). A pKa of 3.70 for 2,3,6-trichlorophenylacetic acid(3) also indicates that it will not volatilize from water as it will exist predominately in the ionic form under environmental pHs(SRC). An estimated vapor pressure for 2,3,6-trichlorophenylacetic acid of 1.7x10-5 mm Hg at 25 °C(4) indicates that it will not volatilize from dry soil to the atmosphere(SRC).

Exposure to 2,3,6-trichlorophenylacetic acid by the general population may occur by ingestion of drinking water contaminated by its use to control aquatic plants(1) or as a result of runoff(2) from its use to control field grasses(3). Occupational exposure to 2,3,6-trichlorophenylacetic acid may occur by inhalation and dermal contact during its application as a herbicide(SRC).

52.8% OF A DOSE WAS EXCRETED IN THE URINE OF A LACTATING COW AS 2,3,6-TRICHLOROPHENYLACETIC ACID ESTER GLUCURONIDE & 18.6% AS THE FREE ACID. FENAC COMPONENTS WERE NOT EXCRETED BY EITHER THE FECAL OR MAMMARY ROUTES. FENAC WAS UNMETABOLIZED BY LIVER DRUG-METABOLIZING ENZYMES & RUMINAL MICROFLORA.|No significant ... percutaneous absorption ... .

52.8% OF DOSE WAS EXCRETED IN URINE OF LACTATING COW AS 2,3,6-TRICHLOROPHENYLACETIC ACID ESTER GLUCURONIDE ... .

SYMPTOMATOLOGY (PARTLY INFERENTIAL): 1. FATIGUE, WEAKNESS, ANOREXIA; PERHAPS NAUSEA, VOMITING & DIARRHEA. 2. HYPOREFLEXIA & LETHARGY PROGRESSING TO COMA, WITH CONSTRICTED PUPILS (MIOSIS). 3. FLACCID PARALYSIS HAS BEEN DESCRIBED IN ONE COMATOSE PT & GRAND MAL CONVULSIONS WITH OPISTHOTONOS IN ANOTHER, HYPERTONIA WITH AREFLEXIA IN A THIRD, & TWITCHING & JERKING IN A FOURTH. ... 5. PROGRESSIVE DECLINE IN BLOOD PRESSURE WITH DEATH IN DEEP COMA. THE POSSIBILITY THAT HYPERPYREXIA & HYPERMETABOLISM MAY HAVE CONTRIBUTED TO THE FATAL OUTCOME DOES NOT APPEAR TO HAVE BEEN RULED OUT (ONE COMATOSE PATIENT WAS DESCRIBED AS SWEATING PROFUSELY). A TERMINAL PNEUMONIA IS LIKELY. 6. DISTURBANCES IN BODY TEMP REGULATION MAY BE ENCOUNTERED. PERHAPS SEVERE REDUCTION OF BODY TEMP IN COOL OR COLD ENVIRONMENTS. MORE PROBABLY, FEBRILE RESPONSES IN WARM ENVIRONMENTS OR DURING EXERCISE. 7. PROGRESSIVE HYPOTENSION WITH DEATH IN PERIPHERAL VASCULAR COLLAPSE, PERHAPS ASSOCIATED WITH ACIDOSIS DUE TO LACTIC ACIDEMIA & OTHER PRODUCTS OF HYPERMETABOLISM. 8. IN NONFATAL POISONINGS, SEVERE & PROTRACTED ... /PRC: NEUROPATHY/ WITH PAIN, PARESTHESIAS & WEAKNESS. ... HUMANS HAVE EXPERIENCED MUSCLE FASCICULATIONS AS WELL AS MYOTONIA. CHRONIC EXPOSURE MAY LEAD TO CENTRAL NERVOUS SYSTEM DEFECTS IN THE CONTROL OF MOTOR FUNCTION. /2,4-D/

2,3,6-trichlorophenylacetic acid

`FENATROL', AQUEOUS CONCENTRATE OF CHLORFENAC-SODIUM; ALSO MIXTURES: CHLORFENAC + AMINOTRIAZOLE + ATRAZINE; CHLORFENAC + BROMACIL; CHLORFENAC + 2,4-D.|FENAC CONSISTS OF 70% OF 2,3,6-TRICHLOROPHENYLACETIC ACID & 30% OF STRUCTURAL ISOMERS.

Benzeneacetic acid, 2,3,6-trichloro-: ACTIVE|... USUALLY APPLIED AS SODIUM SALT, IS ... ABSORBED PRIMARILY BY ROOTS ... USED TO CONTROL ANNUAL GRASSES, BROAD-LEAVED WEEDS, FIELD BINDWEED, COUCH GRASS & OTHER PERENNIAL WEEDS IN INDUST & OTHER NON-CROP SITUATIONS @ RATES UP TO 18 KG AE/HA. ... ALSO USED FOR PRE-EMERGENCE WEED CONTROL IN SUGARCANE ... .|EFFECTIVE AGAINST SUBMERGED AQUATIC WEEDS WHEN APPLIED TO SOIL BEFORE FLOODING.|Closely related to silvex.

PRODUCT ANALYSIS IS BY GLC; RESIDUES MAY BE DETERMINED BY GLC OF SUITABLE DERIVATIVES.

HERBICIDES