Butyl (2,4-dichlorophenoxy)acetate

277.14

277.14

202-364-8

6GO3LVR34R

409767

3082|2765

DTXSID5020443

2918990090

35.53000

4.25

2,4-d, n-butyl ester is a clear colorless to light brown liquid. (NTP, 1992)

1.2±0.1 g/cm3

9 °C

146-147 °C @ Press: 1 Torr

132.0±22.7 °C

1.518

H2O: <0.1 g/100 mL at 21 ºC

0-6°C

6.16X10-5 mm Hg @ 25 deg C

Oral-Rat  LD50: 600 mg/kg; Oral-Mouse LD50: 380 mg/kg

Combustion produces toxic chloride gas

Evaporation rate = 4.45 ug/sq cm/hr at 38 °C at 56.4 l/hr flow and surface area to mass ratio of 3.28 sq cm/g.|HIGHLY VOLATILE|Fuel oil-like odor /2,4-D esters/ SRP: Technical product.|May attack some forms of plastics /2,4-D esters/|For more Other Experimental Properties (Complete) data for 2,4-D BUTYL ESTER (6 total), please visit the HSDB record page.

Insoluble in water.

Esters, Sulfate Esters, Phosphate Esters, Thiophosphate Esters, and Borate Esters

2,4-D, N-BUTYL ESTER is an ester. Esters react with acids to liberate heat along with alcohols and acids. Strong oxidizing acids may cause a vigorous reaction that is sufficiently exothermic to ignite the reaction products. Heat is also generated by the interaction of esters with caustic solutions. Flammable hydrogen is generated by mixing esters with alkali metals and hydrides.

2.05 kcal/mol

III

6.1(b)

UN 3082

3

22-43-50/53

26-29-36/37-46-60-61

AG8050000

Xn;N,N,Xn

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

Stable. Incompatible with strong oxidizing agents.

P273-P280-P501

H302-H317-H410

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number U240, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste. /2,4-D acid, salts & esters/|Group I Containers: Combustible containers from organic or metallo-organic pesticides (except organic mercury, lead, cadmium, or arsenic compounds) should be disposed of in pesticide incinerators or in specified landfill sites. /Organic or metallo-organic pesticides/|Group II Containers: Non-combustible containers from organic or metallo-organic pesticides (except organic mercury, lead, cadmium, or arsenic compounds) must first be triple-rinsed. Containers that are in good condition may be returned to the manufacturer or formulator of the pesticide product, or to a drum reconditioner for reuse with the same type of pesticide product, if such reuse is legal under Department of Transportation regulations (eg 49 CFR 173.28). Containers that are not to be reused should be punctured ... and transported to a scrap metal facility for recycling, disposal or burial in a designated landfill. /Organic or metallo-organic pesticides/|The following wastewater treatment technologies have been investigated for 2,4-D butyl ester: Concentration process: Activated carbon.|For more Disposal Methods (Complete) data for 2,4-D BUTYL ESTER (7 total), please visit the HSDB record page.

WHO; Environ Health Criteria: 2,4-Dichlorophenoxyacetic Acid (2,4-D) (1984)|Nat'l Research Council Canada; Phenoxyherbicides (1978) NRCC No. 16075|Veterans Administration; Review of Literature on Herbicides, Including Phenoxy Herbicides and Associated Dioxins Vol I (1981) VA Contract No. V101(93)P-823|Drinking Water Criteria Doc: 2,4-Dichlorophenoxyacetic acid (2,4-D) 1985 (Draft) ECAO-CIN 418|Que Hee SS, Sutherland RG; The Phenoxyalkanoic Herbicides. Volume 1: Chemistry, Analysis, and Environmental Pollution. CRC Press, Boca Raton, Florida, 1981.

Flash point data for this chemical are not available. It is probably combustible. (NTP, 1992)

|Warning|H302 (100%): Harmful if swallowed [Warning Acute toxicity, oral]|P261, P264, P270, P272, P273, P280, P301+P312, P302+P352, P321, P330, P333+P313, P363, P391, and P501|Aggregated GHS information provided by 146 companies from 2 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

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)

SMALL SPILLS AND LEAKAGE: If you spill this chemical, FIRST REMOVE ALL SOURCES OF IGNITION. Then, use absorbent paper to pick up all liquid spill material. Your contaminated clothing and absorbent paper should be sealed in a vapor-tight plastic bag for eventual disposal. Solvent wash all contaminated surfaces with ethanol followed by washing with a soap and water solution. Do not reenter the contaminated area until the Safety Officer (or other responsible person) has verified that the area has been properly cleaned. STORAGE PRECAUTIONS: You should store this material in a refrigerator. (NTP, 1992)

RECOMMENDED RESPIRATOR: Where the neat test chemical is weighed and diluted, wear a NIOSH-approved half face respirator equipped with an organic vapor/acid gas cartridge (specific for organic vapors, HCl, acid gas and SO2) with a dust/mist filter. (NTP, 1992)

EXTINGUISH WITH DRY CHEMICALS, FOAM, OR CARBON DIOXIDE. WATER MAY BE INEFFECTIVE. COOL EXPOSED CONTAINERS WITH WATER. /2,4-D ESTERS/

Smoking, eating, and drinking before washing should be absolutely prohibited when any pesticide ... is being handled or used. /Pesticides/|/When/ cleaning glassware and spray equipment: wash thoroughly with water and detergent soln. Alcohol or ketone type solvents may be used with ester formulations. Preferably, equipment should not be used for application of other pesticides or fertilizers. /2,4-D ester/

No person may /transport,/ offer or accept a hazardous material for transportation in commerce unless that person is registered in conformance ... and the hazardous material is properly classed, described, packaged, marked, labeled, and in condition for shipment as required or authorized by ... /the hazardous materials regulations (49 CFR 171-177)./|The International Air Transport Association (IATA) Dangerous Goods Regulations are published by the IATA Dangerous Goods Board pursuant to IATA Resolutions 618 and 619 and constitute a manual of industry carrier regulations to be followed by all IATA Member airlines when transporting hazardous materials.|The International Maritime Dangerous Goods Code lays down basic principles for transporting hazardous chemicals. Detailed recommendations for individual substances and a number of recommendations for good practice are included in the classes dealing with such substances. A general index of technical names has also been compiled. This index should always be consulted when attempting to locate the appropriate procedures to be used when shipping any substance or article.

Acute eye or skin irritation ... has been reported in agricultural and forestry workers following occupational exposure. /2,4-D herbicides/|Irritating to skin and eyes. /2,4-D esters/

Permissible Exposure Limit: Table Z-1 8-hr Time Weighted Avg: 10 mg/cu m. /2,4-D/

Recommended Exposure Limit: 10 Hr Time-Weighted Avg: 10 mg/cu m. /2,4-D/

Listed as a hazardous air pollutant (HAP) generally known or suspected to cause serious health problems. The Clean Air Act, as amended in 1990, directs EPA to set standards requiring major sources to sharply reduce routine emissions of toxic pollutants. EPA is required to establish and phase in specific performance based standards for all air emission sources that emit one or more of the listed pollutants. 2,4-D Butyl ester is included on this list.

D016; A waste containing 2,4-D (such as 2,4-D butyl ester) may or may not be characterized as a hazardous waste following testing by the Toxicity Characteristic Leaching Procedure as prescribed by the Resource Conservation and Recovery Act (RCRA) regulations.|U240; A toxic waste when a discarded commercial chemical product or manufacturing chemical intermediate or an off-specification commercial chemical product or a manufacturing chemical intermediate. /2,4-D, salts and esters/

Persons in charge of vessels or facilities are required to notify the National Response Center (NRC) immediately, when there is a release of this designated hazardous substance, in an amount equal to or greater than its reportable quantity of 100 lb or 45.4 kg. The toll free number of the NRC is (800) 424-8802; In the Washington D.C. metropolitan area (202) 426-2675. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV. D.3.b). /2,4-D, salts and esters/

D016; A solid waste containing 2,4-D (such as 2,4-D butyl ester) may or may not become characterized as a hazardous waste when subjected to the Toxicity Characteristic Leaching Procedure listed in 40 CFR 261.24, and if so characterized, must be managed as a hazardous waste.|U240; As stipulated in 40 CFR 261.33, when 2,4-D acid, salts & esters as commercial chemical products or manufacturing chemical intermediates or off-specification commercial chemical products or manufacturing chemical intermediates, become wastes, they must be managed according to Federal and/or State hazardous waste regulations. Also defined as a hazardous waste is any residue, contaminated soil, water, or other debris resulting from the cleanup of a spill, into water or on dry land, of this waste. Generators of small quantities of this waste may qualify for partial exclusion from hazardous waste regulations (40 CFR 261.5). /2,4-D, salts and esters/

In Saskatchewan, 1972, at Saskatoon the 33 day mean daily level of 2,4-D /as butyl ester 2,4-D equivalents/ in air was 600 ng/cu m. Peak was 455 ug/cu m/day.|RESIDUES OF 2,4-D WERE OBSERVED IN AIR IN CENTRAL AND SOUTHERN SASKATCHEWAN DURING THE 1966-8 AND 1970-5 SPRAYING SEASONS. UP TO HALF OF THE DAILY SAMPLES CONTAINED 2,4-D, WITH BUTYL ESTERS BEING PRESENT MOST FREQUENTLY.|The daily mean concentration of mixed 2,4-D butyl esters ranged from 0.01 to 13.50 ug/cu m at various locations in Saskatchewan, Canada during the spraying season in 1966-1973(1). Values over a decade of monitoring were generally between 0.01 and 1 ug/cu m, and seldom exceeded 5 ug/cu m(3). Although, 2,4-D butyl ester was detected in 50% of sampling days(3). The concn of 2,4-D butyl ester was measured as part of the National Air Pesticide Monitoring Program which covered selected areas in 14-16 states during 1970-1972. Of the 2,497 samples analyzed, 0.8% had detectable levels of 2,4-D butyl ester with a mean value of 19 ng/cu m and max value of 59.6 ng/cu m(2). Only South Dakota, North Carolina, Louisiana and Kansas had residues of 2,4-D butyl ester(2). At Pullman, WA in 1964, the avg 24-hr concn of 2,4-D butyl ester was 0.05 ug/cu m avg (max,1.04 ug/cu m max; 13 of 99 days positive); at Kennewick, WA, the avg 24-hr concn of 2,4-D butyl ester was 0.079 ug/cu m (max, 0.82 ug/cu m; 22 of 102 days positive)(3). In a study in South Central Washington, the avg concns of 2,4-D butyl ester ranged from 0.06 to 0.13 ug/cu m at 8 sites in April to June 1974; the highly volatile 2,4-D butyl ester represented 75% of the total chlorophenoxy herbicide burden(4). At Saskatoon, Saskatchewan, Canada in the year 1972, the 33 day mean daily level of 2,4-D butyl ester (2,4-D equivalents in air) was 600 ng/cu m with a peak of 455 ug/cu m/day(5).

highly toxic

IN STATIC BIOASSAYS WITH FINGERLING RAINBOW TROUT, 1 MG/L CARBARYL DECR LC50 OF 2,4-D BUTYL ESTER FROM 30 TO 11 MG/L.|Cutthroat trout (Salmo clarki) were treated with six different paired mixtures of dicamba, picloram, 2,4-D butyl ester, 2,4-D isooctyl ester, and 2,4-D propylene glycol butyl ether ester. Except for 2,4-D isooctyl ester, the LC50's resulting from mixtures of 2,4-D esters and picloram were lower than LC50's of those herbicides tested individually. Dicamba and 2,4-D isooctyl ester were the least toxic individually and mixtures of dicamba or 2,4-D isooctyl ester with the other herbicides tested did not result in increased toxicity. Results reflect the importance of using combination exposures in determining the biological significance of the simultaneous occurrence of more than one herbicide in surface waters.|The aim of this investigation was to determine the contribution made by the different components of herbicide formulations to the overall toxicity of the formulations. Three related herbicide formulations were chosen. The first, Agent Orange, consisted only of the butyl esters of 2,4,5-T and 2,4-D. The second was Agent Orange diluted with diesel fuel and the third formulation tested was a tree and blackberry killer, which consisted of the butyl ester of 2,4,5-T, the ethyl ester of 2,4-D, diesel fuel and two surfactants. The potential toxic effects of these three formulations were evaluated by determining their inhibitory effects on the oxidative functions of submitochondrial particles prepared from beef heart mitochondria. The effective concentration that caused a 50% inhibition of the activities of the submitochondrial particles was determined for all three formulations. When the toxicity of the individual components of these formulations was evaluated, it was established that the so-called 'inert' components i.e. diesel fuel and surfactants contributed approximately 50% of the overall toxicity of the complete formulations. Hence the results confirm the importance of evaluating the toxicity of complete formulations, rather than only focussing on the active components. While cellular and sub-cellular assays cannot account for pharmacokinetic and pharmacodynamic changes that may affect the toxicity of xenobiotics, the sub-mitochondrial particle test is useful as an initial screening assay.

LD50 Mouse oral 380 mg/kg|LD50 Rat oral 920 mg/kg|LD50 Chick (M,F) 2000 mg/kg (1350-2960 mg/kg) oral acid equivalent of 1503 mg/kg /From table, 2,4-D butyl esters/|LD50 Rat oral 600 mg/kg|For more Non-Human Toxicity Values (Complete) data for 2,4-D BUTYL ESTER (8 total), please visit the HSDB record page.

2,4-D butyl ester's former production may have resulted in its release to the environment through various waste streams; it's former use as a herbicide(1) would have resulted in its direct release to the environment(SRC). In the early 1970's, the Canada Weed committee recommended that the use of the highly volatile 2,4-D butyl ester be phased out(2). Similarly, the state of Washington banned the use of 2,4-D butyl ester after April 30, 1974 because of drift and subsequent damage to non-target crops(3).

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 530(SRC), determined from a water solubility of 46 mg/l(2) and a regression-derived equation(3), indicates that 2,4-D butyl ester is expected to have low mobility in soil(SRC). Volatilization of 2,4-D butyl ester from moist soil surfaces is expected to be an important fate process(SRC) given a Henry's Law constant estimated as 4.9X10-7 atm-cu m/mole(SRC) derived from its vapor pressure, 6.16X10-5 mm Hg(4), and its water solubility(2). 2,4-D butyl ester is not expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(4). Following aerial spraying of a forest, 2,4-D butyl ester decomposed within 45 days in the soil(5). 2,4-D butyl ester was applied to soil from Washington, Wyoming and Mississippi in field mini-lysimeters from December to April 1979 (application rates of 560 and 2800 kg/ha); < 1% of the 2,4-D remained in the soil from Washington and Wyoming(6); however the degradation in the acidic Mississippi soil was greatly impeded(6). Phytotoxicity to Fagopyrum tataricum disappeared in loam and sandy loam soil within 2 weeks in non-autoclaved soil and 4 weeks in autoclaved soil(7).|AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 530(SRC), determined from a water solubility of 46 mg/l(2) and a regression-derived equation(3), indicates that 2,4-D butyl ester is expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(3) based upon a Henry's Law constant estimated as 4.9X10-7 atm-cu m/mole(SRC) derived from its vapor pressure, 6.16X10-5 mm Hg(4), and water solubility, 46 mg/l(2). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 83 days and 2.5 years, respectively(SRC). 2,4-D butyl ester is readily metabolized in fish and therefore should not bioconcentrate(5). 2,4-D butyl ester is degraded by acclimated activated sludge at one-half the rate of 2,4-D degradation(6); 2,4-D reached a constant rate of oxidation in 11 weeks(6). 2,4-D butyl ester hydrolyzes slowly in water having a half-life of 5 days at 20 °C and pH 7.4 (7,8). However, the formulated compound was stable for 200 hr at neutral pH(10). The hydrolysis rate increases with increasing pH, disappearing with a half-life of < 5 min at pH 11(9) and is calculated to be 0.2 days at pH 9 and 220 days at pH 6(10). Soil apparently catalyzes the hydrolysis of 2,4-D butyl ester. When it was incubated in 3 different air dried Saskatchewan soils, 70-85% and 67-78% of 2,4-D butyl ester remained after 1.5 hr and 24 hr, respectively(9). When 2,4-D butyl ester water is irradiated with light > 290 nm for 45 hr, 27% of 2,4-D butyl ester disappeared with 2- and 4-chlorophenoxyacetic acid, and 2,4-D formed at 30%, 35% and 7% yields, respectively(11). HCl which was also produced was found to be capable of catalyzing the hydrolysis of 2,4-D butyl ester(11).|ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 2,4-D butyl ester, which has a vapor pressure of 6.16X10-5 mm Hg at 25 deg(2), will exist in both the vapor and particulate phases in the ambient atmosphere(SRC). Vapor-phase 2,4-D butyl ester 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 2.0 days(SRC), calculated from its rate constant of 8.2X10-12 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). Particulate-phase 2,4-D butyl ester may be removed from the air by wet and dry deposition(SRC). 2,4-D butyl ester absorbs light in the environmental spectrum(4) and has the potential for direct photolysis(SRC). When released to the atmosphere during spraying operations, there will be droplet and vapor drift(SRC). The amount of this drift as determined in a field experiment was 25-30% in a half hour after spraying, primarily as the vapor(5). Most of the ester will gravitationally settle out as spray droplets on target crops(5).

The rate constant for the vapor-phase reaction of 2,4-D butyl ester with photochemically-produced hydroxyl radicals has been estimated as 8.2X10-12 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 2.0 days at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). 2,4-D butyl ester hydrolyzes slowly in water having a half-life of 5 days at 20 °C and pH 7.4(2,3). However, the formulated compound was stable for 200 hr at neutral pH(3). The hydrolysis rate increases with increasing pH, disappearing with a half-life of < 5 min at pH 11(4) and is calculated to be 0.2 days at pH 9 and 220 days at pH 6(5). Soil apparently catalyzes the hydrolysis of 2,4-D butyl ester. When it was incubated in 3 different air dried Saskatchewan soils, 70-85% and 67-78% of 2,4-D butyl ester remained after 1.5 hr and 24 hr, respectively(4). However, when the soils contained wilting point moisture levels (5-20% water), only 3-5% of 2,4-D butyl ester was recovered after 1.5 hr and none after 24 hr(4). After 4 weeks, autoclaved soil treated with 2,4-D butyl ester was not phytotoxic to buckwheat plants(6). Therefore, under field conditions with moisture levels at least at the wilting point, hydrolysis of 2,4-D butyl ester should be rapid(6). When 2,4-D butyl ester water is irradiated with light > 290 nm for 45 hr, 27% of 2,4-D butyl ester disappeared with 2- and 4-chlorophenoxyacetic acid, and 2,4-D formed at 30%, 35% and 7% yields, respectively(7). HCl which was also produced was found to be capable of catalyzing the hydrolysis of 2,4-D butyl ester(7). In another study, after 94 and 188 hr in a simulated solar photoreaction, 20% and 34% decomposition occurred (in both the liquid and vapor phase, a situation which typifies a spraying operation), respectively(8). After 188 hr, 14% of the decomposition products formed were highly volatile chlorinated organics, primarily the n-butyl ester of 5-chloro-2-hydroxyphenylacetic acid resulting from ortho dechlorination with simultaneous reduction and rearrangement(8). Assuming first order kinetics, the half-life for decomposition of 2,4-D butyl ester is nearly 13 days(8).

An estimated BCF of 470 was calculated for 2,4-D butyl ester(SRC), using an estimated log Kow of 4.4(1) and a regression-derived equation(2). According to a classification scheme(3), this BCF suggests the potential for bioconcentration in aquatic organisms is high(SRC). However, 2,4-D butyl ester is readily hydrolyzed in fish and therefore should not bioconcentrate(4).

The Koc of 2,4-D butyl ester is estimated as 530(SRC), using a water solubility of 46 mg/l(1) and a regression-derived equation(2). According to a classification scheme(3), this estimated Koc value suggests that 2,4-D butyl ester is expected to have low mobility in soil(SRC). The adsorption of 2,4-D butyl ester to several Canadian prairie soils was attempted using slurries in a batch and soil column experiment(4). 2,4-D butyl ester hydrolyzed to the acid form with a half-life of 100 hr in the batch experiment and on contact in the column experiment(4). In the column experiment, 2,4-D butyl ester leached out essentially as the acid in about an hour(4). Thin layer chromatography resulted in 2,4-D butyl ester being characterized as immobile in soils from Washington, Wyoming, and Mississippi(5). 2,4-D butyl ester is absorbed on clay minerals in the following decreasing order bentonite, illite, and kaolinite(6). The sorbed amounts were very small as is evidenced by the fact that 8.77 g of bentonite, 13.33 g of illite, or 42.73 g of kaolinite are required to reduce the concentration of 2,4-D butyl ester from 3 to 2 mg/l(6). The adsorption of 2,4-D butyl ester to flocculated humic acid is stronger than the free acid and the adsorption follows Freundlich isotherm pattern with a slope of 0.97(7). Therefore, 2,4-D butyl ester will be adsorbed more strongly in soil containing humic materials than clayey soils(SRC).

The Henry's Law constant for 2,4-D butyl ester is estimated as 4.9X10-7 atm-cu m/mole(SRC) derived from its vapor pressure, 6.16X10-5 mm Hg(1), and water solubility, 46 mg/l(2). This Henry's Law constant indicates that 2,4-D butyl ester is expected to volatilize from water surfaces(3). Based on this Henry's Law constant, the volatilization half-life from a model river (1 m deep, flowing 1 m/sec, wind velocity of 3 m/sec)(3) is estimated as 83 days(SRC). The volatilization half- life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec)(3) is estimated as 2.5 years(SRC). 2,4-D butyl ester's estimated Henry's Law constant indicates that volatilization from moist soil surfaces may occur(SRC). 2,4-D butyl ester is not expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(1). In a laboratory volatilization experiment (performed in a cabinet at 38 °C and at an air flow of 940 ml/min), the half-life of 2,4-D butyl ester was 46 hrs(4); the surface area to weight ratio was 3.28 sq cm/g(4). In another experiment designed to simulate a wheat field in a laboratory ecosystem, a high initial concentration of 2,4-D butyl ester in air (140 ug/cu m) was measured only 4 hrs after application(5). The level declined to 2.16 ug/cu m within 48 hr and was only minimally present after 4 days(5). After the initial loss, volatilization is unlikely because the 2,4-D is either hydrolyzed by plants or tightly combined with soil(5).

SURFACE WATER: The concentration of 2,4-D butyl ester was 0.7 mg/l and 4 mg/l in irrigation canal and return flows, respectively, in Southeastern Washington during the irrigation season of 1961(1).

2,4-D WAS ELIM IN MILK OF COWS MAINTAINED IN PASTURES TREATED WITH 2,4-D OR ITS BUTYL OR ISOOCTYL ESTER.

2,4-D and its derivatives can be absorbed via the oral, dermal, and inhalation routes. General population exposure is mainly by the oral route, but under occupational and bystander exposure conditions, the dermal route is by far the most important. /2,4-D and its derivatives/|Occupational exposure to 2,4-D butyl ester may have occurred through inhalation and dermal contact with this compound at workplaces where 2,4-D butyl ester was produced or used. Agricultural workers may have been exposed to 2,4-D butyl ester during spraying operations using herbicides containing this chemical. The general population may have been exposed to 2,4-D butyl ester via inhalation of ambient air with this compound in regions where spraying is performed. (SRC)

Urinalysis of six volunteer workers (wearing a full line of protective clothing) involved in mixing and loading 2,4-D ester solutions into aircraft and in guiding the spray aircraft in two conifer release program showed a maximum excretion level of 22.2 ug/kg body weight/day(1). The urinary excretion rate of 2,4-D in 45 commercial lawn care specialists who had been spraying the herbicide for a period of at least 3 weeks ranged from 0.4-6.3 ug/kg body weight/day(2). Thirty-nine of 197 children living near and away from possible source of contamination had detectable levels of 2,4-D (detection limit 1 ppb) in their urine at a maximum concentration of 9 ppb(3).

2,4-D BUTYL ESTER ADMIN ORALLY TO RABBITS AT 150 OR 490 MG/KG WAS FOUND IN HIGHEST AMOUNTS IN BLOOD, KIDNEYS, LIVER, SPLEEN, LUNG, HEART, AND URINE DURING FIRST 24 HR AFTER ADMIN.|Leaves absorb nonpolar (ester) forms most readily. ... The esters of 2,4-D tend to resist washing from plants and are rapidly converted to the acid by the plants. ... Following foliar absorption, 2,4-D translocates within the phloem, probably moving with food material. Following root absorption, it may move upward in the transpiration stream. Translocation is influenced by the growth status of the plant. Accumulation of the herbicide occurs principally at the meristematic regions of shoots and roots. /2,4-D/|AFTER SC INJECTION OF 2,4-D & ITS BUTYL & ISOOCTYL ESTERS INTO MICE @ 100 MG/KG, ESTERS WERE ELIM RAPIDLY, & ONLY 5-10% OF THE 2,4-D REMAINED AFTER 1 DAY. ... 2,4-D WAS ELIM IN MILK OF COWS MAINTAINED IN PASTURES TREATED WITH 2,4-D OR ITS BUTYL OR ISOOCTYL ESTER.|/RELATIVE/ RATES OF DISAPPEARANCE FROM PLASMA OF 2,4-D OR ITS BUTYL & ISOOCTYL ESTERS FOLLOWING SINGLE SC INJECTIONS OF 100 MG/KG BODY WT OF COMPOUNDS TO FEMALE C57BL/6 MICE WERE: BUTYL ESTER > ISOOCTYL ESTER > 2,4-D.|For more Absorption, Distribution and Excretion (Complete) data for 2,4-D BUTYL ESTER (6 total), please visit the HSDB record page.

MEAL FROM CASTOR BEANS CONTAINED AN ESTERASE THAT HYDROLYZED THE BUTYL ESTER OF 2,4-D ...|The metabolic fate of 2,4-dichlorophenoxyacetic acid (2,4-D) n-butyl ester in rats has not been extensively studied. Upon subcutaneous administration of 100 mg/kg dose of 2,4-D butyl ester to four male Wistar rats, urine samples were analyzed by three analytical techniques for the presence of the butyl ester and metabolites. 2,4-D butylester was rapidly hydrolyzed in the body to form 2,4-D acid. 95% of the administered dose was excreted into the urine as the free acid within 48 hr of injection while only a small fraction (5%) was excreted over an additional 48 hr. No amino acid conjugates or the parent 2,4-D butyl ester could be detected in the urine of treated rats. A minor metabolite (< or = 2% of dose) was detected by GC-MS analysis of urine samples. This compound appears to be a side chain metabolite of the 2,4-D butyl ester. Some chemical properties of the metabolite were characterized, and a 2,4-D hydroxyethyl ester structure proposed. The mechanism of formation of this minor metabolite remains unknown.|Plants hydrolyze 2,4-D esters to 2,4-D, which is the active herbicide. ... Further metabolism ... occurs through three mechanisms, namely, side chain degradation, hydroxylation of the aromatic ring, and conjugation with plant constituents. /2,4-D esters/|HERBICIDAL ACTIVITY OF ESTERS, NITRILES, AMINES (&, OF COURSE, SALTS) APPEARS SIMILAR IF NOT IDENTICAL TO PARENT ACID. THIS IS APPARENTLY DUE TO PRESENCE OF HYDROLYTIC ENZYMES IN PLANTS & IN SOIL MICROORGANISMS THAT CONVERT THESE DERIVATIVES TO PARENT ACID. /2,4-D ESTER/|For more Metabolism/Metabolites (Complete) data for 2,4-D BUTYL ESTER (7 total), please visit the HSDB record page.

THESE HERBICIDES DO NOT ACCUM IN ANIMALS. THEY ARE NOT EXTENSIVELY METAB BUT ARE ACTIVELY EXCRETED INTO THE URINE ... THEIR PLASMA HALF-LIFE IN MAN IS ABOUT 1 DAY. /CHLOROPHENOXY COMPOUNDS/|... In rats orally or intravenously admin, 2,4-D is excreted primarily in the urine with a half-life of approx 2 hr. /SRP: Unspecified salt or ester of 2,4-D/|The hydrolysis half-life of the n-butyl ester of 2,4-D was determined to be 100 hours in neutral water and much less in aqueous soil suspensions. Smith (1976) reported that the n-butyl ester of 2,4-D undergoes almost complete hydrolysis to 2,4-D in less than 24 hours in moist soil. Similar results were reported for the hydrolysis of the n-butyl and isooctyl esters of 2,4,5-T to 2,4,5-T. Esters of 2,4-D were completely hydrolyzed to 2,4-D within 9 days in lake water. Therefore, rates of biological hydrolysis appear to be greater than rates of chemical hydrolysis.

Total alkaloid concentration, percentage water, crude protein, and neutral-detergent fiber in velvet lupine (Lupinus leucophyllus) were monitored for 3 wk following application of herbicides registered or soon to be registered for rangeland use. ... 2,4-D Butyl ester ... killed most velvet lupine plants and caused a subsequent decrease in total alkaloid concentration, crude protein, and water content as the plants desiccated. Herbicides that effectively killed velvet lupine decreased alkaloid levels, thus lowering the potential for increased livestock poisoning.|... /CHLOROPHENOXY CMPD INCL 2,4-D ESTERS/ EXERT THEIR HERBICIDAL ACTION BY ACTING AS GROWTH HORMONES IN PLANTS. /CHLOROPHENOXY COMPOUNDS/|Chlorophenoxy acid derivatives are metabolized via participation of the hepatic microsomal mixed-function oxidase system. Thus, administration of 2,4-D amine salt and its butyl ester ... to rats induced the enzyme system (aminopyrine demethylase ... and aniline hydroxylase ... although the degree of induction was substantially lower than that from phenobarbital. Prolonged administration of 2,4-D amine salt (0.1 LD50) showed cumulative effects reflected by both clinical and biochemical changes. Stimulation of mixed-function oxidase system may be one of the methods for reducing toxicological effects of this type of compounds. /2,4-D butyl ester/|2,4-Dichlorophenoxyacetic butyl ester (2,4-D b.e.) (3.1 mg/egg) was applied on fertile hen eggs before starting the incubation. Chicks hatched from treated eggs showed motor dysfunctions, postural troubles and edematous muscles. The electromyography revealed muscular weakness, prolonged motor distal latency, and myotonia. The biochemical composition of leg and complexus muscles from 1-day-old chicks was determined. A significant diminution (24%) in the glycogen level of leg muscles was produced by the treatment. There was a small increase (15%) in sarcoplasmic proteins from leg muscles and an increase of a 20 kD protein in the myofibrillar proteins from complexus muscles. Even though total lipid content was not changed, 2,4-D b.e. treatment produced a diminution of sterol esters (20%) and phosphatidylcholine (11%) and an increase of phosphatidylserine (61%), triglycerides (37%) and free fatty acids (FFA) (448%) in leg muscles. Increases of phosphatidylethanolamine (16%), sterols (58%) and FFA (267%) were detected in complexus muscles. A remarkable increase (700-1500%) of unsaturated FFA, e.g. oleic, linoleic and arachidonic acids, was observed. Considering the avian embryo lipid metabolism, it is proposed that FFA and triglycerides were accumulated because they could not be metabolized in the mitochondria.

CANADIAN DEPT NATL HEALTH & WELFARE REPORTED ON OCT 23, 1980, THAT SOME COMMERCIAL SAMPLES OF 2,4-D BUTYL ESTER CONTAIN SMALL QUANTITIES OF 2,7- & 2,8-DICHLORODIBENZO-P-DIOXIN, 1,3,7- OR 1,3,8-TRICHLORODIBENZO-P-DIOXIN, & 1,3,6,8-TETRACHLORODIBENZO-P-DIOXIN.|SIXTEEN SAMPLES OF 2,4-D, AS ESTERS AND AMINE SALTS, WERE ANALYZED FOR CHLORINATED DIBENZO-P-DIOXINS. DI-, TRI-, & TETRA-CHLORODIBENZO-P-DIOXINS WERE IDENTIFIED. ESTER FORMULATIONS SHOWED MUCH HIGHER LEVELS OF CONTAMINATION THAN AMINE /2,4-D ESTERS AND AMINE SALTS/

SYMPTOMS: Symptoms of exposure to this compound may include local irritation of the skin, eyes and nasal passages, anorexia, diarrhea, nausea, vomiting, weakness, stupor, muscle twitching, convulsions, decrease in body temperature and coma. ACUTE/CHRONIC HAZARDS: This compound may cause irritation on contact. When heated to decomposition it emits toxic fumes. (NTP, 1992)

EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop. SKIN: IMMEDIATELY flood affected skin with water while removing and isolating all contaminated clothing. Gently wash all affected skin areas thoroughly with soap and water. If symptoms such as redness or irritation develop, IMMEDIATELY call a physician and be prepared to transport the victim to a hospital for treatment. INHALATION: IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. If symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop, call a physician and be prepared to transport the victim to a hospital. Provide proper respiratory protection to rescuers entering an unknown atmosphere. Whenever possible, Self-Contained Breathing Apparatus (SCBA) should be used; if not available, use a level of protection greater than or equal to that advised under Protective Clothing. INGESTION: DO NOT INDUCE VOMITING. If the victim is conscious and not convulsing, give 1 or 2 glasses of water to dilute the chemical and IMMEDIATELY call a hospital or poison control center. Be prepared to transport the victim to a hospital if advised by a physician. If the victim is convulsing or unconscious, do not give anything by mouth, ensure that the victim's airway is open and lay the victim on his/her side with the head lower than the body. DO NOT INDUCE VOMITING. IMMEDIATELY transport the victim to a hospital. (NTP, 1992)

Basic treatment: Establish a patent airway. Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if necessary. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . Monitor for shock and treat if necessary ... . Anticipate seizures and treat if necessary ... . For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with normal saline during transport ... . Do not use emetics. For ingestion, rinse mouth and administer 5 ml/kg up to 200 ml of water for dilution if the patient can swallow, has a strong gag reflex, and does not drool. Administer activated charcoal ... . Monitor body temperature and treat if necessary. /Chlorophenoxy herbicides and related compounds/|Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious. Positive pressure ventilation techniques with a bag valve mask device may be beneficial. Monitor cardiac rhythm and treat arrhythmias if necessary ... . Start an IV with lactated Ringer's /SRP: "To keep open", minimal flow rate/. Titrate to maintain adequate urine flow. Watch for signs of fluid overload. Monitor cardiac rhythm and treat arrhythmias if necessary ... . Consider drug therapy for pulmonary edema ... . For hypotension with signs of hypovolemia, administer fluid cautiously. Consider vasopressors if hypotensive without signs of hypovolemia ... . Treat seizures with diazepam ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Chlorophenoxy herbicides and related compounds/|Alkaline diuresis should be used to treat acute poisoning with chlorophenoxy herbicides or ioxynil in the presence of coma or other poor prognostic indicators, such as acidemia, or if plasma total chlorophenoxy concentrations are 0.5 g/l or more.

The risk of soft tissue sarcoma following possible exposure to phenoxy acid herbicides was studied in 354,620 Swedish men, who were employed in agriculture or forestry according to a national census in 1960. This cohort was further divided into six subcorhorts, on assumed exposure to phenoxy acid herbicides. The reference cohort encompased 1,725,845 Swedish men employed in other industries. All persons were followed up in the cancer-environment register during the period 1961-79. A total of 331 cases of soft tissue sarcomas was observed in the study cohort and there were 1,508 cases in the reference group (relative risk 0.9; 95% confidence interval, 0.8-1.0). No subcohort of agricultural or forestry workers showed any significantly increased relative risk, nor was there any significant difference in relative risk between the subcohorts. Despite the greatly increased use of phenoxy acid herbicides from 1947 to 1970, no time-related increase in the relative risk of soft tissue sarcoma was found in the total cohort or in any of the subcohorts. /Phenoxy acid herbicides/|IN THREE HUMAN BEINGS, ABSORPTION OF AN UNSPECIFIED ESTER OF DICHLOROPHENOXYACETIC ACID THROUGH SKIN CAUSED POLYNEURITIS, BUT WITH NO DISTURBANCE OF EYES OR VISION. /2,4-D ESTER/|SUBJECTIVE CLINICAL SYMPTOMS REPORTED AMONG WORKERS USING VARIOUS ESTERS & SALTS OF 2,4-D INCL RAPID FATIGUE, HEADACHE, LOSS OF APPETITE & PAIN IN THE REGION OF THE LIVER & STOMACH. SENSITIVITY TO TASTE & SMELL WAS LOWERED. /2,4-D ESTERS AND SALTS/|The chlorophenoxy herbicides have produced contact dermatitis in man ... /Chlorophenoxy compounds/|IN THE BODY, THE ... ESTERS OF CHLOROPHENOXY COMPOUNDS ARE HYDROLYZED FAIRLY RAPIDLY SO THAT THE MAMMALIAN TOXICITY OF EACH COMPOUND DEPENDS MAINLY ON THE ACID INVOLVED. /CHLOROPHENOXY HERBICIDES/

2,4-D n-butyl ester

75% AS A SELECTIVE HERBICIDE FOR BROADLEAF WEEDS & BRUSH, ON SMALL GRAINS, CORN, SORGHUM, RICE, OTHER MINOR CROPS, & GRAZING LAND; 13% FOR INDUSTRIAL & COMMERCIAL USE ON NON-CROPLAND; 6% BY GOVERNMENT AGENCIES ON NON-CROPLAND; 6% FOR HOME & GARDEN USE ON TURF (1972) /2,4-D, AMINE SALTS, & ESTERS/|PASTURE & RANGELANDS, 26%; WHEAT, 26%; CORN, 14%; INDUSTRIAL/COMMERCIAL USES, 11%; LAWNS & TURF, 4%; AQUATIC USES, 3%; GRAIN SORGHUM, 3%; RICE, 1%; OTHER GRAINS, 11%; OTHER FIELD CROPS-EG, DECIDUOUS NUTS & FRUITS, CITRUS, & VEGETABLES, 2% (1982) /2,4-DICHLOROPHENOXY ACETIC ACID, ESTERS, & SALTS/

2,4-D n-butyl ester is a component of Orange Component, Orange II Component, and Purple Component.|Herbicide orange is a reddish-brown to tan colored liquid ... /which contained the following components/: n-butyl ester of 2,4-D: 49.49%, free acid of 2,4-D: 0.13%, n-butyl ester of 2,4,5-T: 48.75%, free acid of 2,4,5-T: 1.00%, inert ingredients (eg, butyl alcohol and ester moieties): 0.63%.|AS COMPONENT OF 'AGENT ORANGE' (50:50 MIXT OF N-BUTYL ESTERS OF 2,4-D & 2,4,5-T, CONTAINING UP TO 30 MG/KG OR MORE TCDD /2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN/, & OF 'AGENT PURPLE' (50:30:20 MIXT OF N-BUTYL ESTERS OF 2,4-D & N-BUTYL & ISOBUTYL ESTERS OF 2,4,5-T).|Amoco 2,4-D Weed Killer No 5 (butyl & isopropyl esters of 2,4-D)|For more Formulations/Preparations (Complete) data for 2,4-D BUTYL ESTER (33 total), please visit the HSDB record page.

Chlorophenoxy herbicides are applied alone or as mixtures with other herbicides, in solutions, dispersions, or emulsions in water &/or oil, using equipment that produces large droplets to avoid spray drift. /Chlorophenoxy herbicides/|Ester formulations may be used in relatively hard water ... emulsion compatibility test should be made before using with other pesticides or fertilizers. /2,4-D/|New Zealand: The spraying of phenoxyherbicides is restricted within prescribed distances of vineyards. /Phenoxyherbicides/|Ester formulations are purified by vacuum distillation. /2,4-D esters/|For more General Manufacturing Information (Complete) data for 2,4-D BUTYL ESTER (6 total), please visit the HSDB record page.

A gas chromatograph equipped with an electron capture detector and a flame photometric detector is mounted on a Beech 18 aircraft as part of a program to study the vapor drift associated with pesticide spraying operation. Outside air is continuously drawn through a heated inlet tube and 10-cu m portions of the stream are injected into the partition column via a six-port sampling valve. Concentrations as low as 1 ug/cu m of 2,4-D butyl ester can be detected in less than 5 minutes.|Interfering impurities were separated from a 2,4-D butyl ester, picloram mixture, by gas chromatography and the herbicide vapor mixture was determined at 473 K with a carbon dioxide laser optic-acoustic spectrometer.|Whole Plants: Macerate plant tissue with water. Add 0.6 M sodium hydroxide. Reflux or heat on a steam bath. Filter and wash the filter cake with water. Combine the filtrates. Suspend the filter cake in 2 M hydrochloric acid. Reflux or heat on a steam bath. Extract with equal volumes of ether (x3). Combine these with the filtrate. The above acid hydrolysis is done in case there are conjugates resistant to alkaline hydrolysis. The recovery of the above using only the alkaline hydrolysis was greater than 89 to 92% with (14)C-labeled material. ... Continue with a liquid /liquid cleanup, followed by electron capture/gas chromatography quantitiation ... using a pyrex column ... packed with 1:1 10% DC 200/15% QF-1 on 80/100 mesh Chromosorb W (AW-DMCS). The injector, column, and (63)Ni electron capture detector temperatures are 220, 195, and 220 °C, respectively. The flow rate of nitrogen carrier is 80 ml/min. /2,4-D and esters or salts of 2,4-D/|Water: Filter out any particulate matter. Take a 1-l or smaller volume sample. Saturate with sodium chloride. Adjust the pH to < 2 with hydrochloric acid. Extract with acetonitrile (5 x 500 ml). Adjust the saline solution to > pH 13 and extract with diethyl ether (3 x 500 ml). Reacidify to < pH 2 with hydrochloric acid and extract with acetonitrile (5 x 500 ml). Extraction is approximately 99% efficient. ... Continue with a liquid/liquid cleanup, followed by electron capture/gas chromatography quantitation ... using a pyrex column ... packed with 1:1 10% DC 200/15% QF-1 on 80/100 mesh Chromosorb W (AW-DMCS). The injector, column, and (63)Ni electron capture detector temperatures are 220, 195, and 220 °C; respectively. The flow rate of nitrogen carrier is 80 ml/min. /2,4-D and esters or salts of 2,4-D/|For more Analytic Laboratory Methods (Complete) data for 2,4-D BUTYL ESTER (13 total), please visit the HSDB record page.

Fat Samples: Dissolve sample in hot ethanol; reflux for 1 hr, and chill. Add 0.1 N sodium hydroxide. Extract with diethyl ether. ... Continue with a liquid/liquid cleanup, followed by electron capture/gas chromatography quantitation ... using a pyrex column ... packed with 1:1 10% DC 200/15% QF-1 on 80/100 mesh Chromosorb W (AW-DMCS). The injector, column, and (63)nickel electron capture detector temperatures are 220, 195, and 220 °C, respectively. The flow rate of nitrogen carrier is 80 ml/min.|Plasma: This is based on the method for the drug Clofibrate. Add enough hydrochloric acid to the sample for pH < 2. Extract with equal volumes of ether (x3). To measure the 2,4-D in complex form, add aqueous sodium hydroxide to the aqueous layer and ... continue with a liquid/liquid cleanup, followed by electron capture/gas chromatography quantitation ... using a pyrex column ... packed with 1:1 10% DC 200/15% QF-1 on 80/100 mesh Chromosorb W (AW-DMCS). The injector, column, and (63)nickel electron capture detector temperatures are 220, 195, and 220 °C; respectively. The flow rate of nitrogen carrier is 80 ml/min.|Metabolites: This is a general method recommended by McLeod and Wales. Reflux 5 g of tissue for 1 hr with 19 ml of benzene and separate the supernatant from particulates by filtration through a medium-porosity fritted glass funnel via negative pressure. Re-extract the particulate matter again with fresh 10 ml (19:1) acetone/benzene. Combine the filtrates and concentrate to 25 ml. Use the low-temperature bath apparatus as laid out by McLeod and Wales. Further characterization of the actual metabolites has not been accomplished. There is much room for further separation technology.|In General: Renberg's method is simple, but not very quantitative (70 to 82% at 1 to 3 ppm). Homogenize 5 g of tissue in (5 ml of hexane + 10 ml of acetone), eg, with an insertable homogenizer in a dropping funnel with a glass filter disc. Drop the liquid into 1 M hydrochloric acid (5 ml) (use N2 pressure if necessary) in a separatory funnel. Homogenize again with 10 ml of hexane + 5 ml of diethyl ether. Transfer the upper phase to the separatory funnel, shake, and transfer the upper phase to a centrifuge tube. Reextract the aqueous phase with 2 ml/2 ml of diethyl ether/hexane (x2). Combine the extracts in the centrifuge tube. Add sodium sulfate (100 to 300 mg) and centrifuge. Transfer the supernatant to a weighed flask, rinse the sodium sulfate with diethyl ether (3 x 2 ml), combine the washings and supernatant, evaporate the solvent, and calculate the fat content. Dissolve the residue in benzene (1 ml/25 mg fat). Take 3 ml of this and add 3 ml of 0.1 M sodium hydroxide solution. Shake for 5 min and remove the benzene phase. Continue with one of the following methods: 1) a liquid/liquid cleanup, followed by electron capture/gas chromatography quantitation ... using a pyrex column ... packed with 1:1 10% DC 200/15% QF-1 on 80/100 mesh Chromosorb W (AW-DMCS). The injector, column, and (63)nickel electron capture detector temperatures are 220, 195, and 220 °C; respectively. The flow rate of nitrogen carrier is 80 ml/min. 2) an ion exchange clean up in 0.1 M sodium hydroxide.|For more Clinical Laboratory Methods (Complete) data for 2,4-D BUTYL ESTER (6 total), please visit the HSDB record page.

HERBICIDES