Chlorimuron-ethyl

Store in original container only, away from other pesticides, fertilizer, food or feed. Do not contaminate water, food or feed by storage.

Safe Storage of Pesticides. Always store pesticides in their original containers, complete with labels that list ingredients, directions for use, and first aid steps in case of accidental poisoning. Never store pesticides in cabinets with or near food, animal feed, or medical supplies. Do not store pesticides in places where flooding is possible or in places where they might spill or leak into wells, drains, ground water, or surface water.

If a spill occurs, clean it up promptly. Don't wash it away. Instead, sprinkle the spill with sawdust, vermiculite, or kitty litter. Sweep it into a plastic garbage bag, and dispose of it as directed on the pesticide product label.

After Applying a Pesticide, Indoors or Outdoors. To remove pesticide residues, use a bucket to rinse tools or equipment three times, including any containers or utensils that you used when mixing the pesticide. Then pour the rinsewater into the pesticide sprayer and reuse the solution by applying it according to the pesticide product label directions. After applying any pesticide wash your hands and any other parts of your body that may have come in contact with the pesticide..To prevent tracking pesticides inside, remove or rinse your boots or shoes before entering your home. Wash any clothes that have been exposed to a lot of pesticide separately from your regular wash.

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.

May be dispose of on-site or at an approved waste disposal facility. Container disposal: triple rinse (or equivalent), then offer for recycling or reconditioning or puncture and dispose of in sanitary landfill or incinerate if allowed by state and local authorities, by burning. If burned stay out of smoke.

Safe Disposal of Pesticides. The best way to dispose of small amounts of excess pesticides is to use them - apply them - according to the directions on the label. If you cannot use them, ask your neighbors whether they have a similar pest control problem and can use them. If all of the remaining pesticide cannot be properly used, check with your local solid waste management authority, environmental agency, or health department to find out whether your community has a household hazardous waste collection program or a similar program for getting rid of unwanted, leftover pesticides. These authorities can also inform you of any local requirements for pesticide waste disposal.

Safe Disposal of Pesticides. An empty pesticide container can be as hazardous as a full one because of residues left inside. Never reuse such a container. When empty, a pesticide container should be rinsed carefully three times and the rinsewater thoroughly drained back onto the sprayer or the container previously used to mix the pesticide. Use the rinsewater as a pesticide, following label directions. Replace the cap or closure securely. Dispose of the container according to label instructions. Do not puncture or burn a pressurized container like an aerosol - it could explode. Do cut or puncture other empty pesticide containers made of metal or plastic to prevent someone from reusing them. Wrap the empty container and put it in the trash after you have rinsed it.

Avoid contact with skin, eyes or clothing. Wash contaminated clothing with soap and hot water before reuse.

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.

Wear the items of protective clothing the label requires: for example, non-absorbent gloves (not leather or fabric), rubber footwear (not canvas or leather), a hat, goggles, or a dust-mist filter. If no specific clothing is listed, gloves, long-sleeved shirts and long pants, and closed shoes are recommended. You can buy protective clothing and equipment at hardware stores or building supply stores.

Outdoor Applications. Never apply pesticides outdoors on a windy day (winds higher than 10 mph). Position yourself so that a light breeze does not blow pesticide spray or dust into your face.

A tolerance is established for the residues of the herbicide chlorimuron ethyl [ethyl 2-[[[[ (4-chloro-6-methoxypyrimidin-2yl) amino]carbonyl] amino]sulfonyl] benzoate] in or on the following raw agricultural commodities: peanut, 0.02 ppm; and soybean, 0.05 ppm.

BAS 145 138 protected corn from injury due to low levels of chlorimuron ethyl. Inhibition of root growth was used to monitor injury. BAS 145 138 did not affect uptake, but it caused a two fold increase in the rate of chlorimuron ethyl metabolism in corn roots and shoots. The increase in chlorimuron ethyl metabolism was correlated positively to growth. Routes of metabolism that were accelerated in response to BAS 145 138 included hydroxylation of chlorimuron ethyl at the 5-position of the pyrimidine ring, the formation of the corresponding glucoside, the formation of two glutathione conjugates, and the formation of two unidentified metabolites. The most dramatic of the effects was on the formation of the glucoside of 5-hydroxychlorimuron ethyl. In the roots, the level of this metabolite was increased six fold in response to BAS 145 138. Part of this increase was due to an elevation in the in vivo rate of glucosylation of 5-hydroxychlorimuron ethyl. BAS 145 138 did not alter the qualitative routes of chlorimuron ethyl metabolism, nor did it appear to affect the levels or catalytic properties of acetolactate synthase, the target enzyme of chlorimuron ethyl. 5-Hydroxychlorimuron ethyl was 152 times less effective as an inhibitor of acetolactate synthase than chlorimuron ethyl. The glucoside of 5-hydroxychlorimuron ethyl was hydrolyzed during the acetolactate synthase assay; therefore, an I50 value for this metabolite was not obtained.

EC50; Species: Chlorella vulgaris (Green algae); Conditions: freshwater; static; Concentration: 19236.4 ug/L for 4 day; Effect: population, population growth rate /92.6% technical product formulated product/

EC50; Species: Daphnia magna (Water flea); Conditions: freshwater; static; Concentration: > 10000 ug/L for 2 day; Effect: intoxication, immobile /96% AI formulated product/[USEPA, Office of Pesticide Programs; Pesticide Ecotoxicity Database (2000) on 2-[[[

LC50; Species: Lepomis macrochirus (Bluegill); Conditions: freshwater; static; Concentration: > 2000 ug/L for 4 day /96% AI formulated product/[USEPA, Office of Pesticide Programs; Pesticide Ecotoxicity Database (2000) on 2-[[[

LC50; Species: Oncorhynchus mykiss (Rainbow trout); Conditions: freshwater; static; Concentration: 8400 ug/L for 4 day /96% AI formulated product/[USEPA, Office of Pesticide Programs; Pesticide Ecotoxicity Database (2000) on 2-[[[

For more Ecotoxicity Values (Complete) data for CHLORIMURON-ETHYL (7 total), please visit the HSDB record page.

TERRESTRIAL FATE: Based on a classification scheme(1), Koc values in the range of 30 to 170 measured in 4 soils(2), indicates that chlorimuron-ethyl is expected to have high to very high mobility in soil(SRC). Volatilization of chlorimuron-ethyl from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 1.8X10-15 atm-cu m/mole (SRC) derived from its vapor pressure, 4X10-12 mm Hg(2), and water solubility, 1,200 mg/L(3). Chlorimuron-ethyl is not expected to volatilize from dry soil surfaces(SRC), based upon its vapor pressure(2). Chlorimuron-ethyl has a reported half-life in soil of 53 days under aerobic conditions(2). The photolysis half-life of chlorimuron-ethyl applied to a soil (pH 5.8) was approximately 36 days(2).

TERRESTRIAL FATE: The biodegradation half-life of chlorimuron-ethyl in a sandy loam and a silt loam maintained under aerobic conditions was reported as 53 days(1). The terrestrial field dissipation half-life of chlorimuron-ethyl was <14 days, <14 days, 28-42 days, and 14-28 days when applied to fields located in Fayetteville, NC, Stoneville, MS, Rochelle, IL, and Newark, DE, respectively(1).

AQUATIC FATE: Based on a classification scheme(1), Koc values in the range of 30 to 170 measured in soil(2), indicate that chlorimuron-ethyl is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is not expected(3) based upon an estimated Henry's Law constant of 1.8X10-15 atm-cu m/mole (SRC) derived from its vapor pressure, 4X10-12 mm Hg(2), and water solubility, 1,200 mg/L(4). According to a classification scheme(5), an estimated BCF of 17(SRC), from its log Kow of 2.50(6) and a regression-derived equation(7), suggests the potential for bioconcentration in aquatic organisms is low(SRC). The aqueous hydrolysis half-life of chlorimuron-ethyl at 25 °C is approximately 17 days at pH 5 and less than 3.5 days at pH 7-9(2), and the aqueous photolysis half-life at pH 5 and 25 °C is approximately 12 days(1) although hydrolysis may be contributing to the dergadation.

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), chlorimuron-ethyl, which has a measured vapor pressure of 4X10-12 mm Hg at 25 °C(2), will exist solely in the particulate phase in the ambient atmosphere. Particulate-phase chlorimuron-ethyl may be physically removed from the air by wet and dry deposition(SRC).

The average (maximum) runoff of chlorimuron-ethyl from 3 treated farm plots in Maryland over a 3 year period ranged from 0.025-0.17 ug/L(0.34-2.96 ug/L) for field A, 0.18-1.08 ug/L (5-25.3 ug/L) for field B, and 0.07-0.18 ug/L (0.29-0.47 ug/L) for field C(1).

Chlorimuron-ethyl

Hematologic

2 x 10 ^-2 mg/kg-day

The Koc of chlorimuron-ethyl ranged from 30 in a sandy loam (pH 6.6, 1.1% organic matter) to 170 in a silt loam (pH 5.2, 7.5% organic matter)(1). According to a classification scheme(2), these Koc values indicate that chlorimuron-ethyl is expected to have high to very high mobility in soil(SRC).

/EPIDEMIOLOGY STUDIES/ ...Eight of 16 herbicides were associated with wheeze /among 2,255 Iowa commercial pesticide applicators enrolled in the Agricultural Health Study/ in single-agent models; the risk was almost exclusively associated with the herbicide chlorimuron-ethyl (odds ratio (OR) = 1.62, 95% confidence interval (CI): 1.25, 2.10). Inclusion of chlorimuron-ethyl in models for the other herbicides virtually eliminated the associations. The odds ratios for four organophosphate insecticides (terbufos, fonofos, chlorpyrifos, and phorate) were elevated when these chemicals were modeled individually and remained elevated when chlorimuron-ethyl was included. The association for dichlorvos was not attenuated by chlorimuron-ethyl (OR = 2.48, 95% CI: 1.08, 5.66). Dose-response trends were observed for chlorimuron-ethyl, chlorpyrifos, and phorate; the strongest odds ratio was for applying chlorpyrifos on more than 40 days per year (OR = 2.40, 95% CI: 1.24, 4.65).

Chlorimuron-ethyl's production may result in its release to the environment through various waste streams(SRC); its use as a post-emergence herbicide for soya beans and peanut crops(1) will result in its direct release to the environment(SRC).

An estimated BCF value of 17 was calculated in fish for chlorimuron-ethyl(SRC), using a measured log Kow of 2.50(1) and a regression-derived equation(2). According to a recommended classification scheme(3), this BCF value suggests the potential for bioconcentration in aquatic organisms is low(SRC).

The Henry's Law constant for chlorimuron-ethyl is estimated as 1.8X10-15 atm-cu m/mole(SRC) from its experimental values for vapor pressure, 4X10-12 mm Hg(1), and water solubility, 1,200 mg/L(2). This value indicates that chlorimuron-ethyl will be essentially nonvolatile from water and moist soil surfaces(SRC). Chlorimuron-ethyl is not expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(1).

/LABORATORY ANIMALS: Subchronic or Prechronic Exposure/ In a 4-week range-finding study using mice, the only effect observed was absolute and relative organ weight change; no clinical signs or histopathologic findings were reported. In subchronic toxicity studies, no adverse effects were observed at the highest dose tested (1030/1151 mg/kg/day (M/F)) in mice, whereas decreased body weight gain and liver pathology (margination of hepatocyte cytoplasmic content in the centrilobular areas) were observed in rats (173/209 mg/kg/day (M/F) and mild hemolytic anemia and atrophy of the thymus and prostate were observed in dogs (45.8/42.7 mg/kg/day) at the LOAEL for each respective study. Hemolytic anemia occurred in high-dose male dogs, characterized by macrocytic hyperchromatic anemia, and accompanied by extramedullary hematopoiesis, reticulocytosis, presence of Howell-Jolly bodies, echinocytes, anisocytes, nucleated erythrocytes, enlarged spleen and liver, and bone marrow hyperplasia. These symptoms are indicative of regenerative hemolytic anemia. The LOAEL for the subchronic dog study (45.8/42.7 mg/kg/day (M/F)) was considerably less than that of the rat study (173/209 mg/kg/day (M/F)).

/LABORATORY ANIMALS: Chronic Exposure or Carcinogenicity/ In the chronic feeding study using dogs mild anemia was observed at study termination, but atrophy of the thymus and prostate observed in the subchronic study, was not seen in the chronic study. Mild anemia was observed at the 3-month interval in the chronic study using dogs, but the results were inconsistent at the 6- and 9-month intervals. ...The LOAEL (124/181 mg/kg/day (M/F)) for dogs in the long-term study was lower than the LOAEL (177/214 (M/F)) for rats indicating that the dog was more sensitive to chlorimuron-ethyl than the rat.

/LABORATORY ANIMALS: Chronic Exposure or Carcinogenicity/ Two studies were available for chlorimuron-ethyl administered in the diet of rats; a 1-year interim sacrifice and a 2-year study. At the one-year interim sacrifice of the 2-year study using rats, females had decreased body weight, prostatitis was observed in males, fatty replacement was observed in the pancreas in both sexes, and biliary hyperplasia/fibrosis was observed in females. The only finding observed in the 2-year rat study was decreased body weight and weight gain in females; the deficit in body weight for male rats did not reach a level indicative of the maximum tolerated dose (MTD) at any time during the study. The decrease in weight gain for female rats greatly exceeded the maximum tolerated dose indicating that female rats were more sensitive to chlorimuron-ethyl toxicity than males in the chronic study. The LOAEL (124/181 mg/kg/day (M/F)) for dogs in the long-term study was lower than the LOAEL (177/214 (M/F)) for rats indicating that the dog was more sensitive to chlorimuron-ethyl than the rat. The 18-month mouse and chronic rat studies provided no evidence of potential carcinogenicity for chlorimuron-ethyl.

Chlorimuron-ethyl is listed in the dataset of EPA Human Health Benchmarks for Pesticides under the Safe Drinking Water Act (40 eCFR 141)

Status: Active Update: 12-04-2018 https://echa.europa.eu/registration-dossier/-/registered-dossier/23804

Chlorimuron-ethyl: Does not have an individual approval but may be used as a component in a product covered by a group standard. It is not approved for use as a chemical in its own right.

A tolerance is established for the residues of the herbicide chlorimuron ethyl [ethyl 2-[[[[ (4-chloro-6-methoxypyrimidin-2yl) amino]carbonyl] amino]sulfonyl] benzoate] in or on the following raw agricultural commodities: peanut and soybean.

The Agency has evaluated all current registered uses of chlorimuron ethyl and has determined, based on adequate data, that there is a reasonable certainty that no harm to any population subgroup will result from exposure to chlorimuron ethyl when considering dietary (including both food and drinking water) exposure. In the case of chlorimuron ethyl there are no other non-occupational sources of pesticide exposure. No acute dietary endpoint was identified for chlorimuron ethyl, and the chronic dietary risk estimates for the general U.S. and all population subgroups are less than 1% of the cPAD (chronic population adjusted dose). Therefore, no mitigation measures are needed, and the current tolerances established at 40 CFR 180.429 for residues of chlorimuron ethyl in/on raw agricultural commodities are now considered reassessed under section 408(q) of the FFDCA.

New Active Ingredients ... includes pesticide active ingredients initially registered after November 1, 1984, that currently have active product registrations. By law, these newer pesticides are not subject to the reregistration program. They must, however, meet the new safety standard of the FQPA, and will be reviewed on a 15-year cycle under the registration review program. ... Active Ingredient Number: 128901; Type of Pesticide: conventional - herbicide; Use Site: food use and non-food use; Year: 1986.

Used as sulfonylurea herbicide to control weeds in soybeans and peanuts; [Reference #1]

Farming (Pesticides) [Category: Industry]

For chlorimuron-ethyl (USEPA/OPP Pesticide Code: 128901) ACTIVE products with label matches. /SRP: Registered for use in the U.S. but approved pesticide uses may change periodically and so federal, state and local authorities must be consulted for currently approved uses./

Herbicide

Chlorimuron-ethyl is a sulfonylurea class herbicide with registered food/feed uses in the U.S. on soybeans and peanuts.

Herbicide; Selective postemergence annual broadleaf, yellow nutsedge weed control in peanuts and soybeans.

May be applied ... by band treatment, broadcast, ground spray, low volume spray, or soil incorporated treatment at the current maximum application rate of 0.0825 lbs active ingredient per acre (per crop cycle)(soybean); by band treatment, broadcast, or low volume spray at the current maximum application rate of 0.0078125 lbs active ingredient per acre (per crop cycle) (peanut); by broadcast at the current maximum application rate of 0.03125 lbs active ingredient per acre (non-crop land at foliar stage)

Discontinued Trade names: Concert, Gemini, Lorox Plus, Mulexyl, Preview, Reliance, STS, Skermish.

Chlorimuron-ethyl is produced as a water dispersible granular formulation (WDG) and registration is pending for a granular formulation. The active ingredient (ai), chlorimuron-ethyl, ranges from 8.3 to 31.8% in the registered end-use formulations.

Dry formulation

Selective sulfonylurea herbicide

There are no residential uses