Diclofop-methyl

341.19

341.19

257-141-8

3077

DTXSID0032605

Colorless crystals

2918990090

44.8

4.24

Dark brown Liquid free of visible impurities.

1.3±0.1 g/cm3

39-41 °C

175-177 °C @ Press: 0.1 Torr

38 deg C (Closed cup)

1.562

In water at 22 deg C, 3 mg/l. Readily soluble in common organic solvents, eg, acetone 2490, diethyl ether 2280, xylene 2530, ethanol 110, light petroleum (BP 60-95 deg C) 60 (all in g/l at 20 deg C).

0-6°C

0.034 mPa at 20 deg C

Oral-Rat  LD50: 512 mg/kg; Oral-Mouse LD50: 586 mg/kg

Combustion produces toxic chloride gas

Odorless

Slightly soluble in water (3 mg/l).

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

A bridged diphenyl.

Non-corrosive

UN 3077

2

22-43-50/53

24-37-60-61

UF1180000

Xn;N,N,Xn

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

Decomposed by UV irradiation, and by strong acids and alkalis.

P273-P280-P501

H302-H317-H410

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/

WHO; Environ Health Criteria: Phenoxyherbicides (1984).|Nat'l Research Council Canada; Phenoxy herbicides NRCC No. 16075 (1978).

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]|P261, P264, P270, P272, P273, P280, P301+P312, P302+P352, P321, P330, P333+P313, P363, P391, and P501|H302 (100%): Harmful if swallowed [Warning Acute toxicity, oral]|Aggregated GHS information provided by 226 companies from 4 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)]: 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)|Goggles, rubber gloves, hat, impermeable pants and shirts, waterproof boots.|Aerial pilots are not to be involved in the mixing and loading unless /gloves, waterproof boots, impermeable pants and shirts, goggles and a cartridge type respirator/ is worn. Pilots must wear a cartridge type respirator during application unless the air craft is equipped with an air-filter system.

Avoid contact with flames or sparks.|Avoid contact or inhalation of spray mist. Wash thoroughly after using and change clothing. Do not take internally.|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. Quality assurance to ascertain the completeness of the cleaning procedures should be implemented before the decontaminated protective clothing is returned for reuse by the workers. Contaminated clothing should not be taken home at end of shift, but should remain at employee's place of work for cleaning.

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.

Irritate skin and mucous membranes. /Chlorophenoxy compounds; from table/

moderately toxic

LD50 Rat percutaneous >5000 mg/kg|LD50 Rat female dermal >5000 mg/kg|LD50 Rat acute oral 580 mg/kg

Dichlorfop-methyl's use as a herbicide(1) will result in its release to the environment through various herbicidal applications(SRC).

TERRESTRIAL FATE: In soil, dichlorfop-methyl will be slightly mobile to immobile(1) based on experimental and estimated Koc values ranging from 2400 to 16,000(2-4). Hydrolysis follows the adsorption of dichlorfop-methyl onto clays(5). After application onto sandy loam plots in May (1.25 kg/ha), only 15% of the applied dichlorfop-methyl was solvent recoverable by October and 37% was associated with the soil in a bound form(6). It has been shown that dichlorfop-methyl undergoes rapid hydrolysis by microorganisms through carboxylation and ether cleavage(7,8). In moist soil, hydrolysis of the ester to the corresponding acid, dichlorfop, is rapid and complete within 9 days(5).|TERRESTRIAL FATE: Following spray application on a wheat field, air samples taken at six different heights above the crop canopy during the first 7 days did not show measurable levels of dichlorfop-methyl, thus indicating minimal losses due to volatilization(1). Analysis of the soil showed that the ester was rapidly hydrolyzed to dichlorfop acid which then underwent decomposition(1). After 126 days, approximately 20% of the initial amount applied could still be recovered from the soil as dichlorfop acid(1). Approximately 27% of the dichlorfop-methyl applied was intercepted by the wheat canopy(1). It was assumed that the remaining 73% had infiltrated down to the soil under the crop canopy(1). There was a rapid decline in the total dichlorfop in the crop canopy so that 5 days after application 5% of the initial amount of dichlorfop applied remained, most being in the form of dichlorfop acid. After 32 days, dissipation of dichlorfop from the crop was essentially complete(1). No dichlorfop acid residues were observed in the mature grain or straw at harvest 88 days after application(1).|AQUATIC FATE: Dichlorfop-methyl will be essentially non-volatile from water based upon an estimated Henry's Law constant of 3.8X10-8 atm-cu m/mol(1,2,SRC). Dichlorfop-methyl has aqueous base-catalyzed half-lives of 6.3 days at pH 9, 63 days at pH of 8, and 1.7 years at pH of 7(3,SRC). Dichlorfop-methyl is expected to have moderate bioconcentration(SRC). Adsorption to sediment may be possible based on high Koc values of 2400 to 16,000(2,4,5,SRC). Dichlorfop-methyl biodegrades faster in the presence of sediment than with water(6).|ATMOSPHERIC FATE: Based on an experimental vapor pressure of approximately 2.5X10-7 mm Hg at 20 °C(1), dichlorfop-methyl will exist in the vapor and particulate phases in the ambient atmosphere(2). In the vapor phase, it will degrade in the atmosphere by reaction with photochemically produced hydroxyl radicals with an estimated half-life of 21 hrs(3). Physical removal of particulate dichlorfop-methyl from air is likely to occur through wet and dry deposition(SRC).

Sunlight falling on the earth's surface is composed of wavelengths greater than about 280 nm ... phenoxy herbicides have an ultraviolet absorption maxima in water in the 280-290 nm range, they ... can absorb radiation and be photochemically degraded. /Phenoxy herbicides/|The rate constant for the vapor-phase reaction of dichlorfop-methyl with photochemically produced hydroxyl radicals has been estimated to be approximately 18X10-12 cu cm/molecule-sec at 25 °C which corresponds to an atmospheric half-life of about 21 hours at an atmospheric concn of 5X10+5 hydroxyl radicals per cu cm(1,SRC). Dichlorfop-methyl has an aqueous base-catalyzed rate constant of 0.13 l/mol-sec which corresponds to half-lives of 6.3 days at pH 9, 63 days at pH of 8, and 1.7 years at pH of 7(2,SRC). Degradation of dichlorfop-methyl in hydroalcoholic solution is catalyzed by clays and involves a solvotic process which proceeds through a nucleophilic substitution at the carboxyl group and cleavage of the ester bond(3).

Based upon an experimental water solubility of 3 mg/l(1), the BCF of dichlorfop-methyl can be estimated to be approximately 300 from a regression-derived equation(2). This estimated BCF value suggests moderate bioconcentration in aquatic organisms(SRC).

1.58e+04 L/kg|Using a structure estimation method based on molecular connectivity indexes, the Koc for dichlorfop-methyl can be estimated to be about 4000(1). The Koc for dichlorfop-methyl can be estimated to be about 2400 based on an estimated water solubility of 3 mg/L(3) and a regression derived equation(2). Koc for dichlorfop-methyl has also been determined to be 16,000(4). According to a suggested classification scheme(5), these estimated and experimental Koc values suggest that dichlorfop-methyl will be slightly mobile to immobile in soil.

The Henry's Law constant for dichlorfop-methyl has been estimated to be 3.8X10-8 atm-cu m/mole using a structure estimation method(1). This value of Henry's Law constant indicates that dichlorfop-methyl is essentially non-volatile from water(2).

SURFACE WATER: In 1984, dichlorfop-methyl was detected in the Turtle River (Canada) at 476 ng/l following a major high water event in late June but was undetectable (<12 ng/l) at other sampling times(1).

In three studies (1980-84, 1980-85, and 1989-91) dichlorfop-methyl (detection limit 0.1 ppm) was not found in the fruits and vegetables examined from the United States and Ontario, Canada(1-3).

... Occupational exposure to chlorophenoxy herbicides ... is known to have occurred during their production, formulation, application & disposal. /Chlorophenoxy herbicides/|Herbicides, such as dichlorfop-methyl, can be absorbed into the body by three routes: dermal contact, inhalation, and ingestion(1).

ESTERS NORMALLY EXHIBIT GREATER HERBICIDAL ACTIVITY THAN PARENT ACIDS, BECAUSE OF IMPROVED ABSORPTION BY TARGET PLANTS. /PHENOXYALKANOIC ACIDS/|The chlorophenoxy compounds are absorbed across the gut wall, lung, and skin. They are not significantly fat storable. Excretion occurs almost entirely by way of the urine. /Chlorphenoxy herbicides/

Diclofop-methyl undergoes extensive hydrolysis to its corresponding carboxylic acid in plants in soil. It is then decarboxylated to phenyl ethyl ether and transformed to the phenol in soil. The phenol may undergo complexing or binding to soil and/or be subjected to further degradative processes involving splitting of the ether linkage to give such products as m-dichlorobenzene or 2,4-dichlorophenol. Ring hydroxylation at the 5-position of the 2,4-dichlorophenol moiety was observed but not the other positions of the phenyl rings in plants and soil.|This herbicide was applied to wheat at the rate of 1 kg/ha. Analyses of plant material indicated the presence of unchanged herbicide in addition to a number of metabolites. The main metabolites were identified with GC-MS as the free acid, 5'-OH-analog, and 3'-OH- and 6'-OH-analogs of the free acid as plant conjugates. The breakdown of diclofop-methyl in moist nonsterile clays and sandy loam was investigated. Rapid hydrolysis to the acid occurred initially. This bound tightly to the soils. Subsequently, there was decarboxylation to the ethyl analog and cleavage of the ethyl moiety to produce 2,4-dichlorophenoxy-p-phenol. In soils, diclofop-methyl ester bond was rapidly hydrolyzed and the substituted propionic acid was aerobically oxidized to carbon dioxide. An intermediate was identified as 4-(2,4-dichlorophenoxy)phenol. Under anaerobic conditions, only a small degree of degradation occurred.

In plants, these chemicals /chlorophenoxy compounds/ mimic the action of auxins, hormones chemically related to indoleacetic acid that stimulate growth. No hormonal activity is observed in mammals and other species, and beyond target organ toxicity that can be associated with the pharmacokinetics, biotransformation, and/or elimination of these chemicals, their mechanism(s) of toxic action are poorly understood. /Chlorophenoxy compounds/

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)

Bath and shampoo with soap and water to remove chemicals from skin and hair. Obtain medical treatment if irritation persists. Individuals with chronic skin disease or known sensitivity to these herbicides should either avoid using them or take strict precautions to avoid contact (respirator, gloves, etc). Flush contaminating chemicals from eyes with copious amounts of clean water for 10-15 minutes. If irritation persists, obtain medical treatment. /Chlorophenoxy cmpd/|If any symptoms of illness occur during or following inhalation of spray, remove victim from contact with the material for at least 2-3 days. Allow subsequent contact with chlorophenoxy compounds only if effective respiratory protection is practiced. /Chlorophenoxy cmpd/|If substantial amounts of chlorophenoxy compounds have been ingested, spontaneous emesis may occur. If vigorous emesis has not occurred, measures should be taken to empty the stomach and limit GI absorption by gastric intubation, aspiration, and lavage, following placement of a cuffed endotracheal tube. Repeated administration of charcoal at half or more the original dosage every 2-4 hr may be beneficial. If gastric aspiration and lavage is not performed due to delay in treatment, and if the patient is fully alert, administer charcoal and laxative orally. Administer iv fluids to accelerate excretion of the chlorophenoxy compound, and to limit concentration of the toxicant in the kidney. A urine flow of 4-6 ml/min is desirable. Iv saline/dextrose has sufficed to rescue comatose patients who drank 2,4-D and mecoprop several hours before hospital admission. Caution: Monitor urine protein and cells, BUN, serum creatinine, serum electrolytes, and fluid intake/output carefully to insure that renal function remains unimpaired and that fluid overload dose not occur. Forced alkaline diuresis has been used successfully in management of suicidal ingestions of chlorophenoxy compounds. Alkalinizing the urine by including sodium bicarbonate (44-88 mEq/l) in the iv solution apparently accelerates excretion of 2,4-D dramatically and mecoprop excretion substantially. Urine pH should be maintained in the 7.5-8.8 range. Include potassium chloride as needed to offset increased potassium losses: add 20-40 mEq of potassium chloride to each liter of iv solution. Monitor serum electrolytes carefully. There may possible be some hazard to the kidneys when urine concentrations of toxicant are very high, so integrity of renal function and fluid balance should be monitored carefully as the chlorophenoxy compound is excreted. Hemodialysis is not likely to be of significant benefit in poisonings by chlorophenoxy compounds because of the extensive protein binding of these chemicals. Follow-up clinical examination should include electromyographic and nerve conduction studies to detect any neuropathic changes and neuromuscular junction defects. /Chlorophenoxy cmpd/

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 subcohorts, on assumed exposure to phenoxy acid herbicides. The reference cohort encompassed 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 1977, a number of patients with soft tissue sarcomas and previous exposure to phenoxyacetic acids were described. Following from these observations, a matched case-control study was made. The results showed that exposure to phenoxyacetic acids or chlorophenols gave an approximately six-fold increase in the risk factor for this type of tumor. It was not possible to determine, however, whether the carcinogenic effect was exerted by these compounds or by impurities such as chlorinated dibenzodioxins and dibenzofurans that in almost all cases were part of the commercial preparations. /Phenoxyacetic acids and chlorophenols/|A number of men with malignant lymphoma of the histiocytic type and previous exposure to phenoxy acids or chlorophenols were observed and reported in 1979. A matched case-control study has therefore been performed with cases of malignant lymphoma (Hodgkin's disease and non-Hodgkin's lymphoma). This included 169 cases and 338 controls. The results indicate that exposure to phenoxy acids, chlorophenols, and organic solvents may be a causative factor for malignant lymphoma. Combined exposure of these chemicals seemed to increase the risk. Exposure to various other agents was not obviously different in cases and in controls. /Phenoxy acids and chlorophenols/|A previous case-control study which used the occupational information available on the New Zealand Cancer Registry found that agricultural workers were at increased risk of developing non-Hodgkin's lymphoma. The findings are now presented for the second phase of the study which entailed interviewing 83 cases of non-Hodgkin's lymphoma registered under code 202 of the International Classification of Diseases together with 168 controls with other types of cancer and 228 general population controls. The findings for the two control groups were similar, and there were no significant differences between cases and controls regarding potential exposure to phenoxyherbicides (odds ratio= 1.4, 90% confidence limits 0.7-2.5, p= 0.26) or chlorophenols (odds ratio= 1.3, 90% confidence limits 0.6-2.7, p= 0.39). The odds ratio for fencing work, necessitating exposure to several potential risk factors including arsenic and sodium pentachlorophenate was 2.0 (90% confidence limits 1.3-3.0, p= 0.01). The odds ratio for employment in a meat works, necessitating potential exposure to 2,4,6-trichlorophenol and zoonotic viruses, was 1.8 (90% confidence limits 1.1-3.1, p= 0.04). There was a significant statistical interaction between the risks associated with these two activities, the odds ratio for involvement in both activities compared with involvement in neither being 5.7 (90% confidence limits 2.3-14.3, p= 0.03). /Phenoxyherbicides, chlorophenols, arsenic, and sodium pentachlorophenate/|For more Human Toxicity Excerpts (Complete) data for DICHLORFOP-METHYL (14 total), please visit the HSDB record page.

dichlofopmethyl

Emulsifiable concentrate, oil in water emulsion.|Technical grade greater than or equal to 93% pure.

Chlorophenoxy herbicides are applied alone or as mixtures with other herbicides, in solutions, dispersions, or emulsions in water and/or oil, using equipment that produces large droplets to avoid spray drift. /Chlorophenoxy herbicides/|New Zealand: The spraying of phenoxyherbicides is restricted within prescribed distances of vineyards. /Phenoxyherbicides/

A PROCEDURE FOR DETECTING CHLOROPHENOXY HERBICIDES IN WATER IS DESCRIBED. EXTRACTED WITH BENZENE, THE EXTRACT IS DILUTED WITH ACETONE TO A SUITABLE VOLUME FOR GLC. THE RESULTS INDICATE THAT THE EXTRACTION METHOD WOULD BE APPLICABLE FOR DETERMINING POSSIBLE WATER CONTAMINATION BY CHLOROPHENOXY ESTERS. /CHLOROPHENOXY HERBICIDES/

Pharmaceuticals|HERBICIDES