Nicosulfuron

410.40500

410.40

601-148-4

CG297D9264

DTXSID6034764

Colorless white solid|Colorless crystals|Tan-colored

2935009013

161.09000

1.64570

White solid

1.445g/cm3

142 °C

719.1±70.0 °C at 760 mmHg

388.7±35.7 °C

1.7000 (estimate)

In water, 1.2X10+4 mg/L at 25 deg C

0-6ºC

2.55E-05mmHg at 25°C

Phenolic

Henry's Law constant = 4.13X10-18 atm-cu m/mol at 25 °C

pKa = 4.60

Hydroxyl radical reaction rate constant = 2.19X10-10 cu cm/molec-sec at 25 °C (est)

UN3077 or UN3082 Environmentally hazardoussubstances, liquid or solid, n.o.s., Hazard Class: 9; Labels:9-Miscellaneous hazardous material, Technical NameRequired.UN 3077 9 / PGIII

1

R36/38

S24/25-S26

US4615000

T

Stable at normal temperatures and pressures.

P273-P305 + P351 + P338-P501

H315-H319-H410

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity 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 and plant life; and conformance with environmental and public health regulations.|Do not contaminate water, food, or feed by disposal. Waste resulting from the use of this product may be disposed of on site or at an approved waste disposal facility. /DuPont Accent Q Herbicide/|SRP: Wastewater from contaminant suppression, cleaning of protective clothing/equipment, or contaminated sites should be contained and evaluated for subject chemical or decomposition product concentrations. Concentrations shall be lower than applicable environmental discharge or disposal criteria. Alternatively, pretreatment and/or discharge to a permitted wastewater treatment facility is acceptable only after review by the governing authority and assurance that "pass through" violations will not occur. Due consideration shall be given to remediation worker exposure (inhalation, dermal and ingestion) as well as fate during treatment, transfer and disposal. If it is not practicable to manage the chemical in this fashion, it must be evaluated in accordance with EPA 40 CFR Part 261, specifically Subpart B, in order to determine the appropriate local, state and federal requirements for disposal.

|Warning|H315 (15.9%): Causes skin irritation [Warning Skin corrosion/irritation]|P264, P273, P280, P302+P352, P305+P351+P338, P321, P332+P313, P337+P313, P362, P391, and P501|Aggregated GHS information provided by 283 companies from 13 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.|H410 (100%): Very toxic to aquatic life with long lasting effects [Warning Hazardous to the aquatic environment, long-term hazard]|P273, P391, and P501|Aggregated GHS information provided by 2 companies from 2 notifications to the ECHA C&L Inventory.

Applicators and other handlers must wear: Long-sleeved shirt and long pants. Chemical resistant gloves Category A (such as butyl rubber, natural rubber, neoprene rubber, or nitrile rubber), all > 14 mils. Shoes plus socks. /DuPont Accent Q Herbicide/|Chemical-resistant gloves ... protective eyewear.|... Restricted-entry interval (REI) of 4 hours. Personal protective equipment (PPE) required for early entry to treated areas that is permitted under the Worker Protection Standard and that involves contact with anything that has been treated, such as plants, soil, or water is: Coveralls, chemical resistant gloves Category A (such as butyl rubber, natural rubber, neoprene rubber, or nitrile rubber), all > or = 14 mils. Shoes plus socks. /DuPont Accent Q Herbicide/

In the event of fire, wear self-contained breathing apparatus. Use personal protective equipment. Evacuate personnel and keep upwind of fire. If area is heavily exposed to fire and if conditions permit, let fire burn itself out since water may increase the area contaminated. Burning chemicals may produce by-products more toxic than the original material. Use water spray. Runoff from fire control may be a pollution hazard. Do not allow run-off from fire fighting to enter drains or water courses. Cool containers / tanks with water spray. Control Runoff. /DuPont Accent Q Herbicide/|Extinguishing Media: Water spray, Foam, Dry chemical, Carbon dioxide (CO2). /DuPont Accent Q Herbicide/

Do not contaminate water when disposing of equipment rinsewater. /DuPont Accent Q Herbicide/|Safeguards (Personnel): Evacuate personnel, thoroughly ventilate area, use self-contained breathing apparatus. /DuPont Accent Q Herbicide/|Accidental Release Measures: Prevent material from entering sewers, waterways, or low areas. Follow applicable Federal, State/Provincial and Local laws/regulations. /DuPont Accent Q Herbicide/|Spill Cleanup: Sweep up and shovel into suitable containers for disposal. /DuPont Accent Q Herbicide/

Use this product only in accordance with its labeling and with the Worker Protection Standard, 40 CFR part 170. /DuPont Accent Q Herbicide/|Do not apply directly to water, to areas where surface water is present or to intertidal areas below the mean high water mark. ... Do not apply where/when conditions could favor runoff. /DuPont Accent Q Herbicide/|Users should: Wash hands before eating, drinking, chewing gum, using tobacco or using the toilet. Remove clothing immediately if pesticide gets inside. Then wash thoroughly and put on clean clothing. /DuPont Accent Q Herbicide/|Follow manufacturer's instructions for cleaning/maintaining personal protective equipment (PPE). If no such instructions for washables, use detergent and hot water. Keep and wash PPE separately from other laundry. /DuPont Accent Q Herbicide/|For more Preventive Measures (Complete) data for Nicosulfuron (9 total), please visit the HSDB record page.

The runoff potential of nicosulfuron from agricultural fields was determined in relation to rainfall intensity. Field experiments in 1992 and 1993 at the Lower Coastal Plain Research Station near Kingston, NC and Upper Peidemont Research Station near Reidsville, NC were conducted. Soil types were a Norfolk sandy loam (fine sandy-loam, siliceous, thermic Typic Paleudult and a Pacolet sandy clay loam (clayey, kaolinic, thermic Typic Kanhapludult, respectively. Concentration of nicosulfuron in runoff from the Coastal Plain soil under conventional and no-till were 1.2 and 2.3%, respectively, of the total pesticide application (0.014 kg/ha). Less than 0.2% was detected in a simulated second rainfall event(1).|Monitoring nicosulfuron runoff and leaching from four farming systems on field-scale coastal plain watersheds in Maryland was undertaken in 1995(1). [Table#7869]

LC50 Rat inhalation 5.47 mg/L/4 hr|LD50 Rat dermal >2000 mg/kg|LD50 Mouse oral >5000 mg/kg|LD50 Rat oral >5000 mg/kg

/AQUATIC SPECIES/ The behavioral effects of short periods (2, 4, 6, 8 hr) of static exposure to prochloraz (imidazole fungicide) and nicosulfuron (sulfonylurea herbicide) were recorded in goldfish (Carassius auratus). Observations were also made in an olfactometer to assess the effects of 8-hr exposures to these two pesticides and to carbofuran (carbamate insecticide) on the behavioral responses to the flow of a solution of four L-amino acids (glycine, alanine, valine, taurine), mixed in the same relative proportions as in the urine of conspecifics. Each pesticide was tested at three sublethal concentrations (25, 50, 100 ug/L), and the behaviors recorded were related to swimming pattern, social interactions, and comfort movements. Static exposures to prochloraz affected horizontal displacements, burst swimming, grouping, and buccal movements. Static exposures to nicosulfuron affected burst swimming and grouping. In pesticide-unexposed fish (control), the flow of the amino acid solution induced attraction, decreased sheltering, and increased horizontal displacements, burst swimming, buccal movements, and antagonistic interactions. Compared to the controls, some of the behavioral responses to the solution of amino acids were significantly different after 8 hr of subacute exposure to prochloraz and carbofuran. Both pesticides decreased attraction and increased sheltering. In addition, carbofuran decreased buccal movements and antagonistic interactions. Contrastingly, exposure to nicosulfuron showed no significant effect. This study further confirms the great vulnerability of fish behavior and chemocommunication processes to exposure to waterborne pesticides.|/AQUATIC SPECIES/ Juvenile goldfish (Carassius auratus) were exposed to three widely used pesticides; carbofuran, diuron, and nicosulfuron. Acetylcholinesterase (AChE) activity and molecular forms of AChE were first characterized in brain and skeletal muscle of unexposed fish. Skeletal muscle had higher AChE activity than brain (306 and 215 nmol/min/mg protein, respectively). In brain, four molecular forms of AChE were found: A12, G4, G2, and G1. In the muscle, three molecular forms were found A12, A8, and G2. AChE activity was then evaluated in both tissues of fish exposed to different concentration of pesticides (5, 50, and 500 ug/L) for 6, 12, 24, and 48 hr. In brain, AChE activity was significantly inhibited during all the periods of exposure in response to 50 ug/L (19-28%) and 500 ug/L (85-87%) carbofuran. Such effect was observed in the muscle only at 500 ug/L (86-92%). Carbofuran had no effect on the distribution of molecular forms. Significant inhibitions (9-12%) of brain AChE activity were also observed in response to diuron and nicosulfuron at 500 ug/L during all periods of exposure and for 50 ug/L nicosulfuron after 24 and 48 hr. This study pointed out short-term effects of exposure to sublethal concentrations of the three pesticides, ranging among different chemical families, on brain and muscle AChE in goldfish.|/AQUATIC SPECIES/ Two sulfonyl urea herbicides, sulfometuron methyl nicosulfuron, were evaluated for effects on limb development (day 0-30) and impact on metamorphosis in Xenopus. In these studies, the rate of tail resorption was monitored as a morphological biomarker of thyroid disruption. A 14-day test starting at stage 60 (ca. day 50) and continuing through stage 66 (ca. day 64) was performed. During the 14-day assay, the rate of tail resorption was monitored by video image capture and tail length digitization at stages 63-66. The NOAEC and LOAEC values for limb development following exposure either to sulfometuron methyl or nicosulfuron were 0.01 and 0.05 mg/L, respectively. Malformations induced by sulfometuron methyl included selective reduction deficiencies distal to the femur. Malformations induced by nicosulfuron were similar to those observed with sulfometuron methyl, but also included a general necrosis of the soft tissue (connective tissue) throughout the hind limb. For sulfometuron methyl, the NOAEC and LOAEC values for tail resorption inhibition were 0.001 and 0.01 mg/L, respectively. For nicosulfuron, the NOAEC and LOAEC values for tail resorption inhibition were 0.0001 and 0.001 mg/L, respectively. Addition of 100 ug/L thyroxin partially reversed the inhibitory effects of both sulfonyl urea herbicides. Results from the studies clearly document the importance of evaluating longer-term developmental processes in amphibians to assess ecological hazard.|/AQUATIC SPECIES/ Analytically impure (approximately 85-88%) and purified (99.5%) preparations of two sulfonylurea herbicides, sulfometuron methyl and nicosulfuron, were evaluated for short- and long-term developmental effects on organogenesis (0-4 days) and limb development (0-30 days), and impact on metamorphosis (tail resorption (50-64 days)). Overall, the analytically impure sulfonylurea herbicides were more developmentally toxic than the purified preparations. Purified preparations did not induce early embryo-larval developmental effects or effects on hind limb development, although the rate of tail resorption was slowed at relatively high concentrations. Tail resorption rates were slowed significantly and abnormal limb development was induced by the analytically impure sulfonylurea herbicides. The process of organogenesis as monitored by the traditional frog embryo teratogenesis assay-Xenopus (FETAX) test was the least sensitive stage of development monitored in this study. Although some maldevelopment was induced at the limit of aqueous solubility of the analytically impure material, the severity of the malformations with the impure preparations was moderate. Based on this study, the analytically impure herbicides were more developmentally toxic than purified preparations of the same herbicides, which exerted little effect at maximum soluble concentrations. Thus, the capacity of purified nicosulfuron and sulfometuron methyl to interfere with amphibian development and maturation seems to be relatively low.

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

TERRESTRIAL FATE: Based on a classification scheme(1), a Koc range of 63.0 to 567.1(2) indicates that nicosulfuron is expected to have very high to moderate mobility in soil(SRC). Sulfonylurea herbicides, such as nicosulfuron, are more mobile in alkaline soils and in soils with lower organic matter content(3). The pKa of nicosulfuron is 4.60(4), indicating that this compound will partially exist in the anion form in the environment and anions generally do not adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts(5). Volatilization of nicosulfuron from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 4.1X10-18 atm-cu m/mole(6). Nicosulfuron is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of <6X10-12 mm Hg at 25 °C(4). Nicosulfuron was less than 1.3% mineralized following 41 days of incubation using 5 soils(7) indicating that biodegradation is not an important environmental fate process in soil(SRC).|TERRESTRIAL FATE: Average field half-life is approximately 21 days at pH 6.5. Half-lives were as follows: 0.75 mo for a soil with 1.3% organic matter and pH 5.5 at Stonevill MS; 0.25 mo for a soil with 1.4% organic matter and pH 6.0 at Newark, DE; 0.5 mo for a soil with 2.4% organic matter and pH 6.0 at Bradenton, FL; 1 mo for a soil with 4.4% organic matter and pH 6.9 at Stettler, Alberta /Canada/|TERRESTRIAL FATE: A field study was undertaken in Tennessee in a surface soil to track the dissipation of nicosulfuron. Field plots were set up in 1997 and 1998 on Sequatchie silt loam (pH 5.7, cation exchange capacity 7.0 cmol/g, 1.3% organic matter, and sand/silt/clay was 27/59/14, respectively). Nicosulfuron was applied at 46 g/ha and in combination with rimsulfuron at 46 g/ha. First order rate constants and associated half-lives observed in 1997 were: 0.13/day, half-life 5.3 days (alone); 0.17/day, half-life 4.2 days (mixture). For 1998: 0.54/day, half-life 1.3 days (alone); 0.32/day, half-life 2.2 days (mixture). Under laboratory conditions, moist Sequatchie silt loam soil at 50% field capacity was employed. Nicosulfuron was added at a concentration of 50.0 ng/g soil, both alone and in combination with rimsulfuron and samples were incubated at 30 °C. First order rate constants and associated half-lives observed were: 0.34/day, half-life 2.0 days (alone); 0.30/day, half-life 2.3 days (mixture)(1).|AQUATIC FATE: Based on a classification scheme(1), Koc values ranging from 63.0 to 567.1 in soils of varying clay mineralogy(2), indicates that nicosulfuron is not expected to adsorb to suspended solids and sediment(SRC). Volatilization of nicosulfuron from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 4.1X10-18 atm-cu m/mole(4). According to a classification scheme(5), an estimated BCF of three(SRC), from its log Kow of -1.8(3) and a regression-derived equation(6), suggests the potential for bioconcentration in aquatic organisms is low(SRC). The main degradation pathway for nicosulfuron is hydrolysis of the sulfonylurea bridge(7). Nicosulfuron was less than 1.3% mineralized following 41 days of incubation using 5 soils(8) indicating that biodegradation is not an important environmental fate process in water(SRC).|ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), nicosulfuron, which has a vapor pressure of <6X10-12 mm Hg at 25 °C(2), is expected to exist solely in the particulate phase in the ambient atmosphere. Particulate-phase nicosulfuron may be removed from the air by wet or dry deposition(SRC). Photolysis half-lives in soil were 60-67 days and in water, 200-250 days at pH 7(2) suggesting that nicosulfuron may be susceptible to direct photolysis by sunlight(SRC).

The main degradation pathway for nicosulfuron is hydrolysis of the sulfonylurea bridge(1). Nicosulfuron at a concentration of 10 ug/mL exhibited hydrolysis rate constants of 12.40X10-2/day (pH 4, 22 °C), 128.16X10-2/day (pH 4, 40 °C), 2.13X10-2/day (pH 7, 40 °C), and 1.34X10-2/day (pH 10, 40 °C)(2); the corresponding half-lives were 5.6, 0.54, 33, and 53 days, respectively(SRC). A hydrolysis half-life of 15 days at pH 5 has been reported; however, nicosulfuron has also been reported as stable to hydrolysis at pH 7 and pH 9(3). Photolysis half-lives in soil were 60-67 days and in water, 14-19 days at pH 5, 200-250 days at pH 7, and 180-200 days at pH 9. Other values reported in soil were 24-43 days at 20 °C, 80-143 days at 20 °C, and in water 15 days at pH 5 and 20 °C(3). Therefore nicosulfuron may be susceptible to direct photolysis by sunlight(SRC).

An estimated BCF of three was calculated in fish for nicosulfuron(SRC), using a log Kow of -1.8(1) and a regression-derived equation(2). According to a classification scheme(3), this BCF suggests the potential for bioconcentration in aquatic organisms is low(SRC).

30.20 L/kg|Sulfonylurea herbicides, such as nicosulfuron, are more mobile in alkaline soils and in soils with lower organic matter content(1). Nicosulfuron was not highly mobile in soils with 2:1 clay minerology, possibly due to chemisorption on the clay minerals. The Koc of nicosulfuron using 10 Iowa soils ranged from 63.0 (Fruitfield Entic Hapludoll, pH 7.8, 0.33% organic matter, 2.1% clay) to 567.1 (Webster Typic Haplaquoll, pH 8.2, 0.61% organic matter, 34.1% clay). Using four Brazilian soils not characterized by a 2:1 clay minerology, the range was 86.6 (Typic Acrustox, pH 4.6, 2.16% organic matter, 60.0% clay) to 112.3 (Typic Acrustox, pH 4.8, 0.94% organic matter, 64.3% clay)(2). Koc values of 14.7, 63.7. 62.0. 82.7. and 31.5 were reported using 5 soils - three Mollisols from the North Central US (a sand, a silt loam, and a silt clay loam) and two Oxisols (a sandy clay loam from Brazil and a clay from Hawaii), respectively. Sorption increased with aging of soils(3). According to a classification scheme(4), this Koc range suggests that nicosulfuron is expected to have very high to moderate mobility in soil. Kd values in four sandy loams at 25 °C were: 0.16 (pH 6.6, 1.1% organic matter) to 1.73 (pH 5.4, 4.3% organic matter), and 0.05-0.7, soil specifications not listed(5). The pKa of nicosulfuron is 4.60(5), indicating that this compound will partially exist in the anion form in the environment and anions generally do not adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts(6).|Average Koc is 39 mL/g at pH 6.5 ... Koc 38.4 and Kd for a soil with 1.1% organic matter and pH 6.6; Koc 28.8 and Kd 0.26 for a soil with 2.1% organic matter and pH 6.5; Koc 78,8 and Kd 1.73 for a soil with 4.3% organic matter an dpH 5.4

The Henry's Law constant for nicosulfuron is estimated as 4.1X10-18 atm-cu m/mole(1). This Henry's Law constant indicates that nicosulfuron is expected to be essentially nonvolatile from water and moist soil surfaces(2). Nicosulfuron is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 6.0X10-12 mm Hg(3).

GROUNDWATER: Nicosulfuron was detected in two of 22 groundwater samples collected in the midwestern US during the summer of 1997 at concentrations of 0.03 and 0.12 ug/L; limit of detection = 0.08 ug/L(1). Nicosulfuron was detected in 53% of 212 water samples (73 surface sites and 25 groundwater sites) from rivers, reservoirs and ground water in the Midwestern United States, 1998. Two of 25 groundwater samples were above the method reporting limit of 0.01 ug/L; the maximum concentration encountered was 0.016 ug/L(2).|SURFACE WATER: Nicosulfuron was detected in 6 of 22 surface water samples collected in the midwestern US during the summer of 1997 at concentrations of 0.3, 0.18, 0.05, 0.65, 0.05, and 0.04 ug/L in the Tensas River, Tendal, LA, Iowa River, Rowan IA, Mississippi River, Clinton, IA, Wabash River, Harmony, IN, Illinois River (site 1), and Illinois River (site 2), respectively. The limit of detection = 0.08 ug/L(1). Nicosulfuron was detected in 53% of 212 water samples (73 surface sites and 25 groundwater sites) from rivers, reservoirs and ground water in the Midwestern United States, 1998. Sixty-seven of 130 stream and river samples were above the method reporting limit of 0.01 ug/L; the maximum concentration encountered was 0.266 ug/L(2).

EXPERIMENTAL: Two female goats weighing 43 kg (#1) and 34 kg (#2) (1.4 and 1.8 mg/kg body weight respectively), were dosed daily for 3 consecutive days in feed rations treated with (pyrimidine2-(14)C)nicosulfuron, sp. act., 62.2 uCi/mg, radiochemical purity, >95%, isotopic purity, 97%, and (pyridine-2-(14)C)nicosulfuron, sp. act., 62.9 uCi/mg, radiochemical purity, >95%, isotopic purity, >99%, respectively. Dosing capsules were prepared with the (14)C-labeled materials, 13C-enriched isomers (C2 position of each respective ring), and nonradioactive nicosulfuron. The capsules were analyzed prior to dosing by LSC for total (14)C-activity and by HPLC for chemical analysis. These capsules were imbedded in a larger gelatin capsule containing 6 g of goat chow. Goat #1 was housed for a 9-day acclimation period, while goat #2 was kept for 11 days. Both goats showed good health and milk production before and during dosing. The dosage represents a daily feeding level of approximately 60 ppm based on the average feed and hay consumption of 1 kg/day. Samples of milk, bile, urine, and feces were collected daily and analyzed by combustion/liquid scintillation counting. A control goat was not used in the study. Milk, bile, urine, and feces were collected at least one day prior to dosing for use as control samples. ... The total (14)C activity measured in milk (pyrimidinyl labeled) by combustion/ LSC was a maximum of 0.03 ppm (0.03% TRR). ...

Occupational exposure to nicosulfuron may occur through inhalation and dermal contact with this compound at workplaces where nicosulfuron is produced or used. Limited monitoring data indicate that the general population may be exposed to nicosulfuron via ingestion of and dermal contact with contaminated water. (SRC)

Two female goats weighing 43 kg (#1) and 34 kg (#2) (1.4 and 1.8 mg/kg bodyweight respectively), were dosed daily for 3 consecutive days in feed rations treated with (pyrimidine2-(14)C)nicosulfuron, sp. act., 62.2 uCi/mg, radiochemical purity, >95%, isotopic purity, 97%, and (pyridine-2-(14)C)nicosulfuron, sp. act., 62.9 uCi/mg, radiochemical purity, >95%, isotopic purity, >99%, respectively. Dosing capsules were prepared with the (14)C-labeled materials, 13C-enriched isomers (C2 position of each respective ring), and nonradioactive nicosulfuron. The capsules were analyzed prior to dosing by LSC for total (14)C-activity and by HPLC for chemical analysis. These capsules were imbedded in a larger gelatin capsule containing 6 g of goat chow. Goat #1 was housed for a 9-day acclimation period, while goat #2 was kept for 11 days. Both goats showed good health and milk production before and during dosing. The dosage represents a daily feeding level of approximately 60 ppm based on the average feed and hay consumption of 1 kg/day. Samples of milk, bile, urine, and feces were collected daily and analyzed by combustion/liquid scintillation counting. A control goat was not used in the study. Milk, bile, urine, and feces were collected at least one day prior to dosing for use as control samples. ... The administered 14C-dosage was excreted in the urine at 46% and 17%, and in the feces at 62% and 32%, respectively for the pyridinyl- and pyrimidinyl-labeled nicosulfuron. Uptake of residues was low for all tissues and organs for either label. The highest level, 0.1 ppm (0.04% of total dose) was in the liver from the goat treated with the pyridinyl label. All other tissues had total readioactive residue (TRR) of approximately 0.07 ppm or less (nicosulfuron equivalents). Radioactivity in the collected bile comprised 0.1% and 0.7% of the total dose, respectively for the pyridinyl- and pyrimidinyl labeled nicosulfuron. ...|The ... /absorption and elimination/ of /nicosulfuron/ (2-(4,6-dimethoxy-2-pyrimidinyl) aminocarbonylaminosulfonyl-N,N-dimethyl-3-pyridinecarboxamide) was studied in male and female Sprague-Dawley Crl:CDBR rats. Pyridine-2-(14)C nicosulfuron was administered orally at 10 mg/kg or 1000 mg/kg, at 10 mg/kg following oral administration of unlabeled nicosulfuron at 10 mg/kg/day for 14 days, and intravenously at 10 mg/kg. Pyrimidine-2-(14)C labeled nicosulfuron was also administered orally at 1000 mg/kg. Total recovery of administered radioactivity 4 days postdosing accounted for 98-109% of the dose. Most of the radioactivity was excreted unchanged within 24 hours post dosing. With oral dosing, there were no apparent differences between sexes or dose groups, although a slightly greater percentage of the administered radioactivity was detected in feces of animals receiving the high dose than in animals receiving the low dose. Following oral dosing, elimination in the feces accounted for 80 to 95% of the dose, and elimination in the urine accounted for 9 to 20%. Elimination of (14)C-CO2 was negligible (<0.01 of the administered dose). ... Following intravenous administration, approximately 76 to 80% of the dose was eliminated in the urine and 27 to 30% in the feces. Residues in tissues accounted for 0.05 to 0.5% of the dose. The major excretion product in urine and feces was unchanged parent compound. In addition, pyridinesulfonamide (N,N-dimethyl-2-sulfonamide pyridine-3-carboxamide) was detected in the urine and accounted for 1.1 to 5.7% of the dose. Pyridine acid sulfonamide (2-sulfonamidepyridine-3-carboxylic acid) was tentatively identified as a minor metabolite in the feces of orally dosed rats and urine of intravenously dosed rats. ...

Two female goats weighing 43 kg (#1) and 34 kg (#2) (1.4 and 1.8 mg/kg bodyweight respectively), were dosed daily for 3 consecutive days in feed rations treated with (pyrimidine2-(14)C)nicosulfuron, sp. act., 62.2 uCi/mg, radiochemical purity, >95%, isotopic purity, 97%, and (pyridine-2-(14)C)nicosulfuron, sp. act., 62.9 uCi/mg, radiochemical purity, >95%, isotopic purity, >99%, respectively. Dosing capsules were prepared with the (14)C-labeled materials, 13C-enriched isomers (C2 position of each respective ring), and nonradioactive nicosulfuron. The capsules were analyzed prior to dosing by LSC for total (14)C-activity and by HPLC for chemical analysis. These capsules were imbedded in a larger gelatin capsule containing 6 g of goat chow. Goat #1 was housed for a 9-day acclimation period, while goat #2 was kept for 11 days. Both goats showed good health and milk production before and during dosing. The dosage represents a daily feeding level of approximately 60 ppm based on the average feed and hay consumption of 1 kg/day. Samples of milk, bile, urine, and feces were collected daily and analyzed by combustion/liquid scintillation counting. A control goat was not used in the study. Milk, bile, urine, and feces were collected at least one day prior to dosing for use as control samples. ... The proposed metabolic pathway for nicosulfuron in the goat showed primarily three mechanisms: 1) hydrolysis of the sulfonylurea bridge to yield pyridine sulfonamide and pyrimidine amine (both of which undergo additional metabolism); 2) N-demethylation and subsequent loss of sulfur dioxide leading to the cyclized compound N2; and 3) oxidation and conjugation at the 5-position of the pyrimidine ring.|The metabolism of /nicosulfuron/ (2-(4,6-dimethoxy-2-pyrimidinyl) aminocarbonylaminosulfonyl-N,N-dimethyl-3-pyridinecarboxamide (Accent)) was studied in male and female Sprague-Dawley Crl:CDBR rats. Pyridine-2-(14)C Accent was administered orally at 10 mg/kg or 1000 mg/kg, at 10 mg/kg following oral administration of unlabeled Accent at 10 mg/kg/day for 14 days, and intravenously at 10 mg/kg. Pyrimidine-2-(14)C labeled Accent was also administered orally at 1000 mg/kg. ... Metabolites; / pyridinesulfonamide (N,N-dimethyl-2-sulfonamide pyridine-3-carboxamide) and Pyridine acid sulfonamide (2-sulfonamidepyridine-3-carboxylic acid)/ represent hydrolytic cleavage/oxidation of the parent molecule.

The ... /absorption and elimination/ of /nicosulfuron/ (2-(4,6-dimethoxy-2-pyrimidinyl) aminocarbonylaminosulfonyl-N,N-dimethyl-3-pyridinecarboxamide) was studied in male and female Sprague-Dawley Crl:CDBR rats. Pyridine-2-(14)C nicosulfuron was administered orally at 10 mg/kg or 1000 mg/kg, at 10 mg/kg following oral administration of unlabeled nicosulfuron at 10 mg/kg/day for 14 days, and intravenously at 10 mg/kg. Pyrimidine-2-(14)C labeled nicosulfuron was also administered orally at 1000 mg/kg. ... The average total cumulative excretion indicated half-lives between 12 and 24 hours.

/SRP:/ Immediate first aid: Ensure that adequate decontamination has been carried out. If patient is not breathing, start artificial respiration, preferably with a demand valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR if necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on the left side (head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Poisons A and B/|/SRP:/ Basic treatment: Establish a patent airway (oropharyngeal or nasopharyngeal airway, if needed). Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if needed. 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 0.9% saline (NS) 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 ... . Cover skin burns with dry sterile dressings after decontamination ... . /Poisons A and B/|/SRP:/ Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in severe respiratory distress. Positive-pressure ventilation techniques with a bag valve mask device may be beneficial. Consider drug therapy for pulmonary edema ... . Consider administering a beta agonist such as albuterol for severe bronchospasm ... . Monitor cardiac rhythm and treat arrhythmias as necessary ... . Start IV administration of D5W /SRP: "To keep open", minimal flow rate/. Use 0.9% saline (NS) or lactated Ringer's if signs of hypovolemia are present. For hypotension with signs of hypovolemia, administer fluid cautiously. Watch for signs of fluid overload ... . Treat seizures with diazepam or lorazepam ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Poisons A and B/

/GENOTOXICITY/ ... /Nicosulfuron/ (IN V9360-27) (90.6% a.i.) induced no significant damage to chromosomal structure of cultured human lymphocytes in the presence and absence of metabolic activation at 40, 200, 400 or 470 micrograms/mL concentrations. Cells were examined for chromosomal abnormalities. Nicosulfuron was not clastogenic under the conditions of this test. The maximum concentration tested 470 micrograms was the limit of the test compound solubility in the test system satisfies the guideline requirement even in the absence of cytotoxicity.

2-((((4,6-dimethoxy-(2-pyrimidinyl)amino)carbonyl)amino)sulfonyl)-N,N-dimethyl-3-pyridinecarboxamide

Water dispersible granule, suspension concentrate.|Premix Partners: Atrazine; Clopyralid; Dicamba; Diflufenzopyr; Flumetsulam; Metsulfuron-methyl; Rimsulfuron.|Oil dispersion; suspension concentrate; water dispersible granule.|Eti 114 01 H (Nufam Americas Inc.) Nicosulfuron 75%|For more Formulations/Preparations (Complete) data for Nicosulfuron (42 total), please visit the HSDB record page.

The WHO Recommended Classification of Pesticides by Hazard identifies nicosulfuron as unlikely to present an acute hazard in normal use; Main Use: herbicide.|Following first commercial use in 1990, its use has grown to 12% of surveyed corn acres, with a total of 111 thousand kg applied in 1996

Adequate enforcement methodology (high performance liquid chromatography with tandem mass spectrometric (HPLC/MS/MS) detection method) is available to enforce the tolerance expression.|Method: USGS-NWQL O-2060-01; Procedure: high performance liquid chromatography-mass spectrometry; Analyte: nicosulfuron; Matrix: water; Detection Limit: 0.0065 ug/L.|Product by HPLC. Residues in soil and water by GC/ECD or by immunoassay.

Agrochemicals -> Herbicides|Herbicides|Environmental transformation -> Pesticides (parent, predecessor)

Nicosulfuron has known environmental transformation products that include ASDM, AUSN, HMUD, MU-466, S13 (2-amino-4,6-dimethoxypyrimidine), and UCSN.