Quinclorac｜Huagongshe

Huagongshe화공사 화학 정보 인쇄 보고서 · 연구 참고용

HCID 91739생성일: 2026년 10월 27일

3,7-디클로로퀴놀린-8-카르복실산

3,7-디클로로퀴놀린-8-카르복실산

https://huagongshe.com/ko/chemical/91739

3,7-디클로로퀴놀린-8-카르복실산 분자 구조식

식별자 및 물리적 특성

CAS No.	113875-40-4
분자식	C10H5Cl2NO2
평균 분자량	242.05 g/mol
단동위원소 질량	240.96973376 g/mol
SMILES	O=C(O)c1c(Cl)ccc2cc(Cl)cnc12
InChIKey	FFSSWMQPCJRCRV-UHFFFAOYSA-N
PubChem CID	91739
ChEMBL	CHEMBL1893653
ChEBI	CHEBI:81974
EC No.	402-780-1
DTXSID	DTXSID6032641
현지명	3,7-디클로로퀴놀린-8-카르복실산

화학 및 물리적 성질

XLogP	3
극성 표면적	50.2
수소 결합 공여자 수	1
수소 결합 수용자 수	3
회전 가능 결합 수	1
무거운 원자 수	15
형식 전하	0
복잡도	262
농약	HerbicidesActive substance -> EU Pesticides database: Not approvedPesticide (Quinchlorac) -> USDA PDB
냄새	OdorlessFaint odor
밀도	1.75
Color/Form	White/yellow solidColorless crystalline solid
용해도	In water, 0.065 mg/kg (pH 7, 20 °C)Solubility in acetone 2 g/kg, ethanol 2 g/kgIn acetone <1 g/100 mL at 20 °Cpractically insoluble in other organic solvents
Decomposition	When heated to decomposition if emits toxic vapors of /nitrogen oxides and chloride/.
녹는점	274 °C
증기압	log Kow: -0.75 (pH 7). VP: <0.01mPa (20 °C)
Stability/Shelf Life	Stable under recommended storage conditions.
Dissociation Constants	pKa = 4.34
Collision Cross Section	142.6 Å² [M+H]+ [CCS Type: DTBuffer gas: N2Ionization: ESI+Dataset: TOXCASTSource Identifier: DTXSID6032641]139.54 Å² [M+H]+ [CCS Type: TW]

안전 및 규제

GHS 분류	WarningH317: May cause an allergic skin reaction [Warning Sensitization, Skin]P261, P272, P280, P302+P352, P321, P333+P317, P362+P364, and P501 (click each P-code to see the statement)H317 (100%): May cause an allergic skin reaction [Warning Sensitization, Skin]
규제 정보	Quinchlorac is listed in the dataset of EPA Human Health Benchmarks for Pesticides under the Safe Drinking Water Act (40 eCFR 141)2004/129/ECStatus: Active Update: 10-11-2008 https://echa.europa.eu/registration-dossier/-/registered-dossier/5015Quinclorac: 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.
기타 안전 정보	IMAP assessments - 8-Quinolinecarboxylic acid, 3,7-dichloro-: Environment tier I assessment
FIFRA 요건	Tolerances are established for residues of the herbicide quinclorac, including its metabolites and degradates, in or on the commodities in the table in this paragraph. Compliance with the tolerance levels specified in this paragraph is to be determined by measuring only quinclorac, 3,7-dichloro-8-quinolinecarboxylic acid, in or on the commodity.[Table#8535]Tolerances are established for residues of the herbicide quinclorac, including its metabolites and degradates, in or on the commodity in the following table. Compliance with the tolerance levels specified in this paragraph is to be determined by measuring only quinclorac, 3,7-dichloro-8-quinolinecarboxylic acid, and its methyl ester, methyl-3,7-dichloro-8-quinolinecarboxylate, calculated as the stoichiometric equivalent of quinclorac, in or on the commodity: Rapeseed, subgroup 20A (There are no USA registrations).Time-limited tolerances are established for residues of the herbicide quinclorac, including its metabolites and degradates, in or on the commodity in the table in this paragraph. Compliance with the tolerance level specified in this paragraph is to be determined by measuring only quinclorac, 3,7-dichloro-8-quinolinecarboxylic acid, in or on the commodity. The tolerance expires and is revoked on the date specified in the table in this paragraph. Commodity: cranberryExpiration/revocation date: 12/31/12.Quinclorac. Interim Decision (EPA-HQ-OPP-2007-1135). Quinclorac is a systemic herbicide used to control broadleaf and grass weeds via ground spray or aerial application. Currently registered uses of quinclorac include turf grasses, sorghum, wheat, rangeland/pasture, rights-of way/fencerow/hedgerow, grass grown for seed, fallow land, grass forage/fodder/hay, rice, rhubarb, and low growing berry (except strawberry) subgroup 13-07H. EPA conducted a human health risk assessment and did not identify any risks of concern. No human health mitigation is being undertaken for quinclorac at this time by the Agency. However, a data gap is identified by the Quinclorac human health risk assessment: An updated analytical standard for the quinclorac DMA salt to the EPA National Pesticide Standards Repository. The Agency also conducted an ecological risk assessment for existing listed above. For existing uses, risks of concern were identified for listed and non-listed terrestrial plant species as well as listed aquatic vascular plants from use of quinclorac on rice. EPA published an interim proposed registration review decision for quinclorac in the Federal Register on September 24, 2014. The document includes various label changes to mitigate risks to terrestrial plants by reducing spray drift and also calls for updates to quinclorac tolerances. One comment was received on the proposed interim decision, which did not change the conclusions of the decision or the proposed mitigation to address ecological risks. At this time in registration review, it is premature to make an endangered species effects determination for federally listed species and their designated critical habitats under the ESA. Quinclorac has also not yet been evaluated under the EDSP. Therefore, the Agency's final registration review decision is dependent upon the results of the evaluation of risks to threatened and endangered species and of potential endocrine disruptor risk. Pending the outcome of these actions, EPA is issuing an interim registration review decision for quinclorac this time

Skin, Eye, and Respiratory Irritations

Quinclorac (batch no. 83/117purity not stated) produced transient, mild conjunctival effects (scores 0-2) when tested in Vienna White rabbits. Similar results were reported in a more recent study (purity 99.4%) in New Zealand White rabbits./Quinclorac (purity not stated) produced no erythema or edema of the skin when tested in Vienna White rabbits. Similar results were reported in a more recent study (purity 99.4%) in New Zealand White rabbits.

소화 절차	Suitable extinguishing media: Use water spray, alcohol-resistant foam, dry chemical or carbon dioxide.Advice for firefighters: Wear self contained breathing apparatus for fire fighting if necessary.

정리 방법

ACCIDENTAL RELEASE MEASURES: Personal precautions, protective equipment and emergency procedures: Use personal protective equipment. Avoid dust formation. Avoid breathing vapors, mist or gas. Ensure adequate ventilation. Avoid breathing dust. Environmental precautions: Prevent further leakage or spillage if safe to do so. Do not let product enter drains. Discharge into the environment must be avoided. Methods and materials for containment and cleaning up: Pick up and arrange disposal without creating dust. Sweep up and shovel. Keep in suitable, closed containers for disposal.

처리 방법

SRP: 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 qualitypotential migration in air, soil or watereffects on animal, aquatic and plant lifeand conformance with environmental and public health regulations. If it is possible or reasonable use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination.Product: Offer surplus and non-recyclable solutions to a licensed disposal company. Contaminated packaging: Dispose of as unused product.

Preventive Measures

ACCIDENTAL RELEASE MEASURES: Personal precautions, protective equipment and emergency procedures: Use personal protective equipment. Avoid dust formation. Avoid breathing vapors, mist or gas. Ensure adequate ventilation. Avoid breathing dust. Environmental precautions: Prevent further leakage or spillage if safe to do so. Do not let product enter drains. Discharge into the environment must be avoided.Precautions for safe handling: Avoid contact with skin and eyes. Avoid formation of dust and aerosols. Provide appropriate exhaust ventilation at places where dust is formed.Appropriate engineering controls: Handle in accordance with good industrial hygiene and safety practice. Wash hands before breaks and at the end of workday.Gloves must be inspected prior to use. Use proper glove removal technique (without touching glove's outer surface) to avoid skin contact with this product. Dispose of contaminated gloves after use in accordance with applicable laws and good laboratory practices. Wash and dry hands.SRP: Local exhaust ventilation should be applied wherever there is an incidence of point source emissions or dispersion of regulated contaminants in the work area. Ventilation control of the contaminant as close to its point of generation is both the most economical and safest method to minimize personnel exposure to airborne contaminants. Ensure that the local ventilation moves the contaminant away from the worker.

Allowable Tolerances

Tolerances are established for residues of the herbicide quinclorac, including its metabolites and degradates, in or on the commodities in the table in this paragraph. Compliance with the tolerance levels specified in this paragraph is to be determined by measuring only quinclorac, 3,7-dichloro-8-quinolinecarboxylic acid, in or on the commodity.[Table#8534]Tolerances are established for residues of the herbicide quinclorac, including its metabolites and degradates, in or on the commodity in the following table. Compliance with the tolerance levels specified in this paragraph is to be determined by measuring only quinclorac, 3,7-dichloro-8-quinolinecarboxylic acid, and its methyl ester, methyl-3,7-dichloro-8-quinolinecarboxylate, calculated as the stoichiometric equivalent of quinclorac, in or on the commodity: Rapeseed, subgroup 20A, 1.5 ppm (There are no USA registrations).Time-limited tolerances are established for residues of the herbicide quinclorac, including its metabolites and degradates, in or on the commodity in the table in this paragraph. Compliance with the tolerance level specified in this paragraph is to be determined by measuring only quinclorac, 3,7-dichloro-8-quinolinecarboxylic acid, in or on the commodity. The tolerance expires and is revoked on the date specified in the table in this paragraph. Commodity: cranberry, 15.0 ppmExpiration/revocation date: 12/31/12.

Personal Protective Equipment (PPE)

Eye/face protection: Safety glasses with side-shields conforming to EN166. Use equipment for eye protection tested and approved under appropriate government standards such as NIOSH (US) or EN 166(EU).Skin protection: Handle with gloves.Body Protection: Complete suit protecting against chemicals. The type of protective equipment must be selected according to the concentration and amount of the dangerous substance at the specific workplace.Respiratory protection: For nuisance exposures use type P95 (US) or type P1 (EU EN 143) particle respirator. For higher level protection use type OV/AG/P99 (US) or type ABEK-P2 (EU EN 143) respirator cartridges. Use respirators and components tested and approved under appropriate government standards such as NIOSH (US) or CEN (EU).

생태독성 수치

LC50Species: Colinus virginianus (Northern Bobwhite Quail) age 10 daysdiet >5000 ppm for 8 days /96.5% purity/Species: Anas platyrhynchos (Mallard Duck) age 10 daysLD50Species: Anas platyrhynchos (Mallard Duck) age 24 weeksoral via capsule >1900 mg/kg /98.3% purity/Species: Colinus virginianus (Northern Bobwhite Quail) age 20 weeksoral via capsule >2000 mg/kg /98.3% purity/For more Ecotoxicity Values (Complete) data for Quinclorac (18 total), please visit the HSDB record page.

환경 거동

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 470(SRC), determined from a structure estimation method(2), indicates that quinclorac is expected to have moderate mobility in soil(SRC). The pKa of quinclorac is 4.34(3), indicating that this compound will exist partialy in the anion form in the environment and anions generally adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts(4). Volatilization of the neutral species from moist soil surfaces is not expected(4) based upon an estimated Henry's Law constant of 7.6X10-12 atm-cu m/mole(SRC), developed using a fragment constant estimation method(2). Quinclorac is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 4.0X10-8 mm Hg at 25 °C(SRC), determined from a fragment constant method(2). Quinclorac is stable to hydrolysis in sterile water however the compound undergoes rapid photolysis in non-sterile rice paddy, natural river waters and solutions containing activated sludge with half-lives of 5-10 days reported(5). Quincloarac is resistent to biodegradation in soil under aerobic and anaerobic conditions(5), indicating that biodegradation is not an important environmental fate process in soil(SRC).FIELD STUDY: Quinclorac applied to experimental rice fields in Tianjin and Jilin Provinces, China in 1993 and 1994, exhibited rapid dissipation from water, with half-lives of 0.8 and 2 days, respectively. The half-life from rice leaves was <1 daysediment half-life was reported as 6 days. The compound was not detected in associated soils. Levels in rice at pre-harvest interval of 95-105 days was <0.005 mg/kg(1). A field half-life range of 18-176 days has also been reported(2).AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 470(SRC), determined from a structure estimation method(2), indicates that quinclorac is not expected to adsorb to suspended solids and sediment(SRC). A pKa of 4.34(3) indicates quinclorac will exist partially in the anion form at pH values of 5 to 9 and, therefore, volatilization from water surfaces is not expected to be an important fate process(SRC). Volatilization of the neutral species from water surfaces is not expected(4) based upon an estimated Henry's Law constant of 7.6X10-12 atm-cu m/mole(SRC), developed using a fragment constant estimation method(2). Quinclorac was reported to be stable under both UV light and sunlight under aqueous conditions(4) the compound undergoes rapid photolysis in non-sterile rice paddy, natural river waters and solutions containing activated sludge with half-lives of 5-10 days reported. According to a classification scheme(5), a BCF of <1(6) suggests that bioconcentration in aquatic organisms is low(SRC). Biodegradation of <10% was reported in 28 days in an aquatic ready biodegradability test(7), 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), quinclorac, which has an estimated vapor pressure of 4.0X10-8 mm Hg at 25 °C(SRC), determined from a fragment constant method(2), will exist in both the vapor and particulate phases in the ambient atmosphere. Vapor-phase quinclorac 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 13 days(SRC), calculated from its rate constant of 1.3X10-12 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(2). Particulate-phase quinclorac may be removed from the air by wet and dry deposition(SRC). Quinclorac contains chromophores that absorb at wavelengths >290 nm(3) and, therefore, may be susceptible to direct photolysis by sunlight(SRC).

독성 요약

IDENTIFICATION AND USE: Quinclorac is a herbicide. HUMAN STUDIES: It induced chromosomal aberrations in cultured human lymphocytes. ANIMAL STUDIES: It produced no sensitization reactions in a guinea-pig maximization test. Quinclorac was fed to groups of Beagle dogs in the diet at a dose of 0, 1,000, 3,000, 9,000 or 27,000 ppm for 28 days. At 27,000 ppm, feed consumption was reduced in females, and there was body weight loss over the duration of the study in both sexes. Kidney lesions were present at the top dose level. In mice Quinclorac was administered in a diet, at dose levels of 0, 4,000, 8,000, or 16,000 ppm. At 8000 and 16000 ppm there was an increase in water intake in males and females and blood urea nitrogen in males. There was decreased kidney weight in males and females and relative kidney weight in males in the 16,000 ppm group. At 4000 ppm there was decreased body weight gain in males and females. In rats given Quinclorac at dose levels of 0, 1,000, 4,000, or 12,000 ppm in a diet, noted decreases in body weight gain, food consumption and an increase in water intake in males and females, and decrease in monocytes in female, increases in liver enzymes in males, and pathological changes in kidneys of males. Quinclorac did not induce tumors in mice, rats or dogs. In rabbits the developmental toxicity observed at 600 mg/kg/day consisted of increased rate of resorption and post-implantation loss, a decrease in the number of live fetuses, and reduced fetal body weight. No structural anomalies were observed in rats in a 2-generation reproduction study. There were no effects noted for neuropathology or brain weight determinations in rats. Bacterial reverse gene mutation test was negative with or without metabolic activation in Salmonella typhimurium strains TA98, TA100, TA1535, TA1537. ECOTOXICITY STUDIES: When tested in fingerlings of the silver catfish (Rhamdia quelen), acetylcholinesterase (AChE) activity was evaluated in brain and muscle tissue of fish exposed to different herbicide concentrations. Quinclorac caused increases in enzyme activity in the brain and inhibitions in muscle tissue. In fish species Cyprinus carpio exposed to the quinclorac herbicide the levels of antioxidant enzymes and oxidative stress were increased.

생태독성 발췌

/AQUATIC SPECIES/ Fingerlings of the silver catfish (Rhamdia quelen) were exposed to three herbicides widely used in rice culture in south Brazil: clomazone, quinclorac, and metsulfuron methyl. LC50 was determined and acetylcholinesterase (AChE) activity was evaluated in brain and muscle tissue of fish exposed to different herbicide concentrations after 96h (short term). The LC50 value (nominal concentration) was 7.32 mg/L for clomazone and 395 mg/L for quinclorac, but was not obtained for metsulfuron-methyl since all fingerlings survived the highest concentration of 1200 mg/L. Brain and muscle AChE activity in unexposed fish were 17.9 and 9.08 micromol/min/g protein, respectively. Clomazone significantly inhibited AChE activity in both tissues, achieving maximal inhibition of about 83% in brain and 89% in muscle tissue. In contrast, quinclorac and metsulfuron methyl caused increases in enzyme activity in the brain (98 and 179%, respectively) and inhibitions in muscle tissue (88 and 56%, respectively). This study demonstrated short-term effects of exposure to environmentally relevant concentrations of rice field herbicides on AChE activity in brain and muscle tissue of silver catfish./AQUATIC SPECIES/ The occurrence of pollutants in the aquatic environment can produce severe toxic effects on non-target organisms, including fish. These sources of contamination are numerous and include herbicides, which represent a large group of toxic chemicals. Quinclorac, an herbicide widely applied in agriculture, induces oxidative stress due to free radical generation and changes in the antioxidant defense system. The aim of this study was to assess if dietary diphenyl diselenide (PhSe)2 has a protective effect in tissues of fish species Cyprinus carpio exposed to the quinclorac herbicide. The fish were fed with either a standard or a diet containing 3.0 mg/Kg of diphenyl diselenide for 60 days. After were exposed to 1 mg/L of Facet (quinclorac commercial formulation) for 192 hr. At the end of the experimental period, parameters as thiobarbituric acid-reactive substance levels (TBARS), protein carbonyl, catalase (CAT), superoxide dismutase (SOD), glutathione S-transferase (GST), nonprotein thiols (NPSH) and ascorbic acid in the liver, gills, brain and muscle were evaluated in Cyprinus carpio. In fish exposed to quinclorac and feeding with standard diet TBARS levels increased in liver and gills. However, SOD activity decreases in liver whereas no alterations were observed in catalase activity in this tissue. Quinclorac also decrease GST activity in liver and brain, NPSH in brain and muscle and ascorbic acid in muscle. Concerning protein carbonyl exposed to herbicide the fish did not show any alterations. The diphenyl diselenide supplemented diet reversed these effects, preventing increases in TBARS levels in liver and gills. GST activity was recovered to control values in liver. NPSH levels in brain and muscle increased remain near to control values. These results indicated that dietary diphenyl diselenide protects tissues against quinclorac induced oxidative stress ameliorating the antioxidant properties./AQUATIC SPECIES/ This study evaluated parameters of oxidative stress and antioxidant profile in fish after herbicide exposure. Cyprinus carpio were exposed to quinclorac (initial concentration 344.60 ug/L) for 7, 30, and 90 days under rice field condition. Thiobarbituric acid-reactive substances (TBARS) were evaluated in brain, liver and muscle tissues, and protein carbonyl in liver. Enzymatic parameters such as catalase (CAT) and gluthatione S-transferase (GST) activities also were studied in liver. TBARS levels fluctuated in the brain showing increase in 7 days and decrease in 30 days, while in liver it was observed increase in 7 and 30 days, as well as in muscle after 30 and 90 days. The protein carbonyl was also increased after 30 and 90 days of herbicide exposure. CAT and GST activities were decreased after 30 and 90 days, respectively. The alterations observed suggest that a commercial formulation containing quinclorac causes oxidative damage in different tissues of carp after a long time of exposure. This study pointed out the importance of quinclorac toxicity considering the concentration used in rice fields./AQUATIC SPECIES/ In this study, the protective effects of diphenyl diselenide [(PhSe)2] on quinclorac- induced toxicity were investigated in silver catfish (Rhamdia quelen). The fish were fed for 60 days with a diet in the absence or in the presence of 3.0 mg/Kg (PhSe)2. Animals were further exposed to 1 mg/L quinclorac for 8 days. At the end of experimental period, fish were euthanized and biopsies from liver and gills, as well as blood samples, were collected. The cortisol and metabolic parameters were determined in plasma, and those enzyme activities related to osmoregulation were assayed in the gills. In liver, some important enzyme activities of the intermediary metabolism and oxidative stress-related parameters, such as thiobarbituric acid-reactive substance (TBARS), protein carbonyl, catalase (CAT), superoxide dismutase (SOD), glutathione S-transferase (GST), nonprotein thiols (NPSH) and ascorbic acid contents were also evaluated. Compared to the control group, quinclorac exposure significantly decreased hepatosomatic index and increased cortisol and lactate values in plasma. Moreover, the activities of fructose biphosphatase (FBPase), glucose-6-phosphate dehydrogenase (G6Pase), glycogen phosphorilase (GPase) and aspartate aminotransferase (AST) were significantly increased in liver. Quinclorac also induced lipid peroxidation while the activity of SOD, NPSH and ascorbic acid levels decreased in the liver. However, dietary (PhSe)2 reduced the herbicide-induced effects on the studied parameters. In conclusion, (PhSe)2 has beneficial properties based on its ability to attenuate toxicity induced by quinclorac by regulating energy metabolism and oxidative stress-related parameters./OTHER TERRESTRIAL SPECIES/ This work sought to ascertain survival and possible changes in levels of glycogen, triglycerides, total lipids, cholesterol, protein, and lipid peroxidation in gills, liver, and muscle of bullfrog tadpoles (Lithobates catesbeianus) exposed to low concentrations of atrazine (2.5 ug/L), glyphosate (18 ug/L), and quinclorac (0.025 ug/L) at laboratorial conditions. Tadpoles showed a reduction of glycogen and triglyceride in all organs and an increase in lipid peroxidation (LPO) compared with control animals. Total lipid in gills and muscle increased in exposure to atrazine, and gills alone in exposure to glyphosate, but decreased in gills, liver, and muscle after quinclorac. Cholesterol increased in gills and liver after atrazine, in gills and muscle after glyphosate, and decreased in liver after quinclorac. Total protein in gills decreased after exposure to all herbicides, increased in muscle after atrazine, and in liver and muscle after quinclorac. These findings show that at concentrations of these herbicides tested can lead to an increase in energy expenditure to maintain homeostasis and survival of these animals despite the increase in lipid peroxidation levels in all organs analyzed. Responses observed can be one of the factors responsible for the decline in the number of amphibians around the world.

Ongoing Test Status

EPA has released the Interactive Chemical Safety for Sustainability (iCSS) Dashboard. The iCSS Dashboard provides an interactive tool to explore rapid, automated (or in vitro high-throughput) chemical screening data generated by the Toxicity Forecaster (ToxCast) project and the federal Toxicity Testing in the 21st century (Tox21) collaboration. /The title compound was tested by ToxCast and/or Tox21 assays/[USEPAICSS Dashboard ApplicationAvailable from, as of August 9, 2018: http://actor.epa.gov/dashboard/]

Soil Adsorption/Mobility

Using a structure estimation method based on molecular connectivity indices(1), the Koc of quinclorac can be estimated to be 470(SRC). According to a classification scheme(2), this estimated Koc value suggests that quinclorac is expected to have moderate mobility in soil. The pKa of quinclorac is 4.34(3), indicating that this compound will exist partially 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(4).A sorption coefficient Kd of <1 indicates that leaching is a probable route of dissipation in the soil environment. Some leaching was observed, as quinclorac was detected below the 12 inch soil depth in the several of the terrestrial field dissipation studies. Detections of residues of quinclorac and its degradates in the soil down to 42-48 inches were reported in terrestrial field studies performed in KS, CA, MO, and NJ(1). Soil column leaching experiments were conducted using 3 of 5 major soil zones found in Alberta, Canada, and 10 g of quinclorac-spiked soils, equivalent to 120 g/ha. Quinclorac was reported to leach very rapidly (84 to 97% by 0.67 rain year) in brown Skiff loam (pH 6.02.1% OM) and dark brown Lethridge loam (pH 7.62.7% OM). Intermediate leaching (69-76% by 3.0 rain-year) was reported using black Lacombe sandy loam (pH 5.65.9% OM)(2).

Human Toxicity Excerpts

/GENOTOXICITY/ Human lymphocytes (whole blood) were treated with Reg. No. 150 732 (Quinclorac) (technical grade) (purity: 96.5%) at concentrations ranging from 125 to 1500 ug/mL (non activation) or 250 to 2500 ug/mL (activation) at 37 °C for 24 hours (non activation) or 2 hours, followed by an additional 22 hours of incubation (activation), following 48 hours in culture with phytohemaglutinin. The cells were cultured in the presence of Colcemid (1.33 ug/mL) the last 2 to 3 hours of the incubation period. There were duplicate cultures for each treatment level. An Aroclor 1254-derived rat liver S9 fraction was used to metabolize the test material. A treatment-related increase in the incidence of chromosomal aberrations was noted for the non-activated cultures (p<0.01). The highest treatment level examined in the activated samples demonstrated an increase in the incidence of aberrant chromosomes with gaps (p<0.05). However, there was a treatment-related reduction in the mitotic index indicative of increasing cytotoxicity. The chromosomal aberrations may have been a secondary consequence of the cytotoxicity. Possible adverse effect indicated: increased incidence of chromosomal aberrations./GENOTOXICITY/ Human lymphocytes were treated with Reg. No. 150 732 (Quinclorac) (technical grade) (purity: 96.5%) or Reg. No. 150 732 (batch no. CH 384 121) (purity: >98%) at a concentration of 1000 ug/mL under conditions of non activation at 37 °C for 24 hours following 48 hours of stimulation with phytohemagglutinin (PHA). The cells were cultured in the presence of Colcemid (1.33 ug/mL) the last 2 to 3 hours of the incubation period. There were duplicate cultures for each treatment level. A treatment-related increase in the incidence ofchromosomal aberrations was noted for both test materials (p<0.01). Possible adverse effect indicated: increased incidence of chromosomal aberrations./GENOTOXICITY/ In vitro mammalian chromosome aberration assay, human lymphocytes: Positive for chromosomal aberrations but only at cytotoxic concentrations (2000 ug/mL with S9 and 1000 ug/mL without S9). /From table//GENOTOXICITY/ Test: Chromosomal aberrationsTarget: Human lymphocytesConcentration or dose tested: 250, 500 and 1,000 ug/mL (+/-S9)Purity (%): 96.5Results: Positive +/-S9. /From table/

Artificial Pollution Sources	Quinclorac's production may result in its release to the environment through various waste streamsits use as a herbicide to control weeds on agricultural crops, and turf in residential and commercial areas(1) will result in its direct release to the environment(SRC).

Environmental Biodegradation

AEROBIC: Quinclorac is stable to aerobic and anaerobic biodegradation in soil(1). Biodegradation of <10% was reported in 28 days using an unspecified ready aquatic biodegradability test(2). Following an aerobic aquatic metabolism study, it was reported that a primary degradate, 3-chloro-8-quinoline carboxylic acid, was detected at maximum 55.7% of initial radioactivity after 6 months and 30.8% after 12 months(1).

Environmental Bioconcentration	A log BCF of -0.38722 (BCF <1) was reported in fish for quinclorac(SRC), using bluegill (Lepomis macrochirus) which were exposed over a 4-week period in the OPPTS 850.1730 test(1). According to a classification scheme(2), this BCF suggests the potential for bioconcentration in aquatic organisms is low(SRC).

Volatilization from Water/Soil

A pKa of 4.34(1) indicates quinclorac will exist partially in the anion form at pH values of 5 to 9 and, therefore, volatilization from water surfaces is not expected to be an important fate process(SRC). The Henry's Law constant for the neutral species of quinclorac is estimated as 7.6X10-12 atm-cu m/mole(SRC) developed using a fragment constant estimation method(2). This Henry's Law constant indicates that quinclorac is expected to be essentially nonvolatile from water and moist soil surfaces(2). Quinclorac is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 4.0X10-8 mm Hg(SRC), determined from a fragment constant method(2).