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Acaricides, Insecticides

Active substance -> EU Pesticides database: Not approved

Pesticides -> Other Insecticides

Pesticide (Chlorfenapyr) -> USDA PDB

Light tan or light yellow powdered solid

White solid

Soluble in acetone, diethyl ether, DMSO, THF, acetonitrile, alcohols. Insoluble in water

Solubities at 25 °C. [Table#7120]

Solubities in water at 25 °C. [Table#7121]

100-101 °C

MP: 91-92 °C

177.74 Ų [M+H]+ [CCS Type: TW; Buffer gas: N2; Ionization: GC-APCI+]

190.4 Ų [M+HCOO]-

Danger

H302: Harmful if swallowed [Warning Acute toxicity, oral]

P261, P264, P270, P271, P273, P301+P317, P304+P340, P316, P321, P330, P391, P403+P233, P405, and P501 (click each P-code to see the statement)

Danger

H302 (100%): Harmful if swallowed [Warning Acute toxicity, oral]

P261, P264, P270, P271, P273, P301+P317, P304+P340, P316, P321, P330, P391, P403+P233, P405, and P501 (click each P-code to see the statement)

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

2001/697/EC

Chlorfenapyr: HSNO Approval: HSR006718 Approved with controls

A moderate eye irritant; [HSDB] The active metabolite uncouples oxidative phosphorylation in the mitochondria causing cellular death; [Reference #1] In high-dose animal studies, causes liver changes, depressed activity and ataxia; [RTECS] A mild skin and eye irritant based on animal studies; [MSDSonline]

Tolerances are established for residues of the insecticide chlorfenapyr [4-bromo-2-(4-chlorophenyl)-1-(ethoxymethyl)-5-(trifluoromethyl)-1H-pyrrole-3-carbonitrile] in or on the following raw agricultural commodities: vegetables, fruiting, group 8.

A tolerance is established for residues of chlorfenapyr in or on all food commodities (other than those covered by a higher tolerance as a result of use on growing crops) in food/feed handling areas where food/feed products are prepared, held, processed, or served and in accordance with the following prescribed conditions: (i) Application shall be no greater than a 0.5% active ingredient solution for spot crack and crevice use in food/feed handling establishments, where food and food products are held, processed, prepared and/or served. (ii) Application may only be undertaken when the facility is not in operation, and provided exposed food has been covered, or removed from the area being treated prior to application. (iii) Food contact surfaces and equipment should be throughly washed with an effective cleaning compound, and rinsed with potable water after each use of the product. (iv) Contamination of food or food contact surfaces shall be avoided. Application excludes any direct application to any food, food packaging, or any food contact surfaces. (v) To assure safe use, the label and labeling shall conform to that registered by the U.S. Environmental Protection Agency, and it shall be used in accordance with such label and labeling.

Under the authority of Section 3(c)(5), the Agency has determined that the database supports granting an unconditional registration for Chlorfenapyr Technical, and for Pylon Miticide-Insecticide (21.4% chlorfenapyr), for use on ornamentals grown in commercial greenhouses.

/GUIDE 154: SUBSTANCES - TOXIC AND/OR CORROSIVE (NON-COMBUSTIBLE)/ Health: TOXIC; inhalation, ingestion, or skin contact with material may cause severe injury or death. Contact with molten substance may cause severe burns to skin and eyes. Avoid any skin contact. Effects of contact or inhalation may be delayed. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may be corrosive and/or toxic and cause pollution. /Poisonous solid, organic, NOS; Toxic solid, organic, NOS (Chlorfenapyr)/

/GUIDE 154: SUBSTANCES - TOXIC AND/OR CORROSIVE (NON-COMBUSTIBLE)/ Fire or Explosion: Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. Some are oxidizers and may ignite combustibles (wood, paper, oil, clothing, etc.). Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated. /Poisonous solid, organic, NOS; Toxic solid, organic, NOS (Chlorfenapyr)/

/GUIDE 154: SUBSTANCES - TOXIC AND/OR CORROSIVE (NON-COMBUSTIBLE)/ Public Safety: CALL Emergency Response Telephone Number ... . 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. Keep unauthorized personnel away. Stay upwind. Keep out of low areas. Ventilate enclosed areas. /Poisonous solid, organic, NOS; Toxic solid, organic, NOS (Chlorfenapyr)/

/GUIDE 154: SUBSTANCES - TOXIC AND/OR CORROSIVE (NON-COMBUSTIBLE)/ Protective Clothing: Wear positive pressure self-contained breathing apparatus (SCBA). Wear chemical protective clothing that is specifically recommended by the manufacturer. It may provide little or no thermal protection. Structural firefighters' protective clothing provides limited protection in fire situations ONLY; it is not effective in spill situations where direct contact with the substance is possible. /Poisonous solid, organic, NOS; Toxic solid, organic, NOS (Chlorfenapyr)/

For more DOT Emergency Guidelines (Complete) data for CHLORFENAPYR (8 total), please visit the HSDB record page.

Acute Tox. 4 (100%)

Acute toxicity - category 3

Acute toxicity (Oral) - Category 4

Acute Tox. 3 *

Do not store below 32 °F. ... Store in a secure, dry, ventilated area away from children, livestock, and food. Do not store in direct sunlight or heat.

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.

Do not contaminate water, food, or feed by disposal.

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.

Do not get in eyes, on skin, or clothing. Avoid breathing vapor or mist. Harmful if inhaled. Wash thoroughly after handling with soap and water.

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.

Indoor Applications. If the label directions permit, leave all windows open and fans operating after the application is completed. If the pesticide product is only effective in an unventilated (sealed) room or house, do not stay there. Put all pets outdoors, and take yourself any your family away from treated areas for at least the length of time prescribed on the label. Apply most surface sprays only to limited areas such as cracks; don't treat entire floors, walls, or ceilings. Don't let pesticides get on any surfaces that are used for food preparation. Wash any surfaces that may have pesticide residue before placing food on them.

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.

SRP: The scientific literature for the use of contact lenses in industry is conflicting. The benefit or detrimental effects of wearing contact lenses depend not only upon the substance, but also on factors including the form of the substance, characteristics and duration of the exposure, the uses of other eye protection equipment, and the hygiene of the lenses. However, there may be individual substances whose irritating or corrosive properties are such that the wearing of contact lenses would be harmful to the eye. In those specific cases, contact lenses should not be worn. In any event, the usual eye protection equipment should be worn even when contact lenses are in place.

Tolerances are established for residues of the insecticide chlorfenapyr [4-bromo-2-(4-chlorophenyl)-1-(ethoxymethyl)-5-(trifluoromethyl)-1H-pyrrole-3-carbonitrile] in or on the following raw agricultural commodities: vegetables, fruiting, group 8, 1.0 ppm.

A tolerance of 0.01 parts per million is established for residues of chlorfenapyr in or on all food commodities (other than those covered by a higher tolerance as a result of use on growing crops) in food/feed handling areas where food/feed products are prepared, held, processed, or served and in accordance with the following prescribed conditions: (i) Application shall be no greater than a 0.5% active ingredient solution for spot crack and crevice use in food/feed handling establishments, where food and food products are held, processed, prepared and/or served. (ii) Application may only be undertaken when the facility is not in operation, and provided exposed food has been covered, or removed from the area being treated prior to application. (iii) Food contact surfaces and equipment should be throughly washed with an effective cleaning compound, and rinsed with potable water after each use of the product. (iv) Contamination of food or food contact surfaces shall be avoided. Application excludes any direct application to any food, food packaging, or any food contact surfaces. (v) To assure safe use, the label and labeling shall conform to that registered by the U.S. Environmental Protection Agency, and it shall be used in accordance with such label and labeling.

Antidotes to cyanide poisoning include hydroxocobalamin and sodium nitrite, which release the cyanide from the cytochrome system, and rhodanase, which is an enzyme occurring naturally in mammals that combines serum cyanide with thiosulfate, producing comparatively harmless thiocyanate. Oxygen therapy can also be administered. (L97)

Exposure to high levels of cyanide for a short time harms the brain and heart and can even cause coma, seizures, apnea, cardiac arrest and death. Chronic inhalation of cyanide causes breathing difficulties, chest pain, vomiting, blood changes, headaches, and enlargement of the thyroid gland. Skin contact with cyanide salts can irritate and produce sores. (L96, L97)

LC50; Species: Daphnia spp; Concentration: 6.1 ppb/24 to 96 hr; Conditions: not specified /From table/

LD50 /Colinus virginianus/ (Northern bobwhite) oral 34 mg/kg (95% confidence interval 24-49 mg/kg) /from table/

LD50 /Anas platyrhynchos/ (Mallard duck) oral 10.3 mg/kg (95% confidence interval 7.0-15.1 mg/kg) /from table/

LD50 /Agelaius phoeniceus/ (Red-winged blackbird) oral 2.2 mg/kg (95% confidence interval 1.5-4.0 mg/kg) /from table/

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

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 10,000(SRC), determined from a log Kow of 4.83(2) and a regression-derived equation(3), indicates that chlorfenapyr is expected to be immobile in soil(SRC). Volatilization of chlorfenapyr from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 5.7X10-9 atm-cu m/mole(SRC), using a fragment constant estimation method(4). Chlorfenapyr is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 7.4X10-8 mm Hg(SRC), determined from a fragment constant method(5). A biodegradation half-life range of 230-250 days in soil(6) suggest that biodegradation is not an important environmental fate process in soil(SRC).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 10,000(SRC), determined from a log Kow of 4.83(2) and a regression-derived equation(3), indicates that chlorfenapyr is 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 5.7X10-9 atm-cu m/mole(SRC), developed using a fragment constant estimation method(4). BCFs of 83-114 given for bluegill sunfish(5), suggest the potential for bioconcentration in aquatic organisms is moderate to high(SRC). Photolysis is expected to be the principal fate of chlorfenapyr in water(5). A biodegradation half-life of 250 days in sediment(5) suggest 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), chlorfenapyr, which has an estimated vapor pressure of 7.4X10-8 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 chlorfenapyr 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 1.2 days(SRC), calculated from its rate constant of 1.4X10-11 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). Particulate-phase chlorfenapyr may be removed from the air by wet or dry deposition(SRC). Chlorfenapyr photodegrades in sterile fresh water with a half-life of 5-7 days(4), suggesting that photolysis in air may be important(SRC).

Organic nitriles decompose into cyanide ions both in vivo and in vitro. Consequently the primary mechanism of toxicity for organic nitriles is their production of toxic cyanide ions or hydrogen cyanide. Cyanide is an inhibitor of cytochrome c oxidase in the fourth complex of the electron transport chain (found in the membrane of the mitochondria of eukaryotic cells). It complexes with the ferric iron atom in this enzyme. The binding of cyanide to this cytochrome prevents transport of electrons from cytochrome c oxidase to oxygen. As a result, the electron transport chain is disrupted and the cell can no longer aerobically produce ATP for energy. Tissues that mainly depend on aerobic respiration, such as the central nervous system and the heart, are particularly affected. Cyanide is also known produce some of its toxic effects by binding to catalase, glutathione peroxidase, methemoglobin, hydroxocobalamin, phosphatase, tyrosinase, ascorbic acid oxidase, xanthine oxidase, succinic dehydrogenase, and Cu/Zn superoxide dismutase. Cyanide binds to the ferric ion of methemoglobin to form inactive cyanmethemoglobin. (L97)

/BIRDS and MAMMALS/ The acute toxicity of chlorfenapyr to birds is high to very high. The subchronic toxicity to birds is also very high (eg, in mallard ducks, chlorfenapyr at 2.5 ppm in the diet reduced adult body weights and decr egg-laying and hatch rates by about 40 to 60%) ... Although /lab/ results suggest that there is a considerable potential for the use of chlorfenapyr to cause acute and reproductive toxicity in wild birds, there appear to be no reports of detectable impacts on birds or other wildlife when these have been closely monitored in areas where chlorfenapyr has been used.

/AQUATIC SPECIES/ Chlorfenapyr is also very highly toxic to fish and aquatic invertebrates /with LC50 for fish ranged 7.4 to 500 ppb/24 to 96 hr/ ...

/BIRDS and MAMMALS/ Clinical signs of intoxication /in acute studies/ common to all three species included whole body and wing beat convulsions, lethargy and loose green or chalky excreta. In addition, dyspnea (labored breathing) and opisthotonos (head stretched over back) were reported for the mallard. Lethargy was reported in the highest red-winged blackbird dose group. Post-mortem exam showed no treatment related abnormalities other than firm pectoral muscles. A reduction in body weight, as compared to the control animals, occurred in the northern bobwhite at dose levels above 32 mg/kg during the first 3 days of the study. No body weight reduction was noted in the mallards or red-winged blackbirds. A reduction in food consumption, as compared to the control animals, occurred in the northern bobwhite at dose levels above 16 mg/kg during the first 3 days of the study. A similar response was observed in the mallard at treatments higher than 4 mg/kg. These results indicate that chlorfenapyr is very highly toxic to waterfowl and passerine species and highly toxic to upland gamebirds on an acute oral basis.

/BIRDS and MAMMALS/ AC 303,268, a soil photolytic degradate, was shown to kill nearly as quickly as the parent compound and was more toxic to northern bobwhite. Deaths prior to day 4 accounted for 88% of the total mortality observed in mallards and northern bobwhite. Weight loss coincided with decreased food consumption at day 3 at treatment groups 40 mg/kg and higher in the mallard and at 25 mg/kg and higher in the northern bobwhite. Signs of intoxication common to both species included shallow rapid breathing, reduced reaction time, and loss of coordination. Necropsy showed small pale yellow spleens and stained vents. /AC 303,268; soil degradate/

For more Ecotoxicity Excerpts (Complete) data for CHLORFENAPYR (9 total), please visit the HSDB record page.

The Koc of chlorfenapyr is estimated as 10,000(SRC), using a log Kow of 4.83(1) and a regression-derived equation(2). According to a classification scheme(3), this estimated Koc value suggests that chlorfenapyr is expected to be immobile in soil.

Tolerances are established for residues of the insecticide chlorfenapyr [4-bromo-2-(4-chlorophenyl)-1-(ethoxymethyl)-5-(trifluoromethyl)-1H-pyrrole-3-carbonitrile] in or on the following raw agricultural commodities: vegetables, fruiting, group 8.

A tolerance is established for residues of chlorfenapyr in or on all food commodities (other than those covered by a higher tolerance as a result of use on growing crops) in food/feed handling areas where food/feed products are prepared, held, processed, or served and in accordance with the following prescribed conditions: (i) Application shall be no greater than a 0.5% active ingredient solution for spot crack and crevice use in food/feed handling establishments, where food and food products are held, processed, prepared and/or served. (ii) Application may only be undertaken when the facility is not in operation, and provided exposed food has been covered, or removed from the area being treated prior to application. (iii) Food contact surfaces and equipment should be throughly washed with an effective cleaning compound, and rinsed with potable water after each use of the product. (iv) Contamination of food or food contact surfaces shall be avoided. Application excludes any direct application to any food, food packaging, or any food contact surfaces. (v) To assure safe use, the label and labeling shall conform to that registered by the U.S. Environmental Protection Agency, and it shall be used in accordance with such label and labeling.

Under the authority of Section 3(c)(5), the Agency has determined that the database supports granting an unconditional registration for Chlorfenapyr Technical, and for Pylon Miticide-Insecticide (21.4% chlorfenapyr), for use on ornamentals grown in commercial greenhouses.

Chlorfenapyr shows virtually no uncoupling activity but removal of the N-ethoxymethyl group through microsomal oxidation releases the corresponding free pyrrole (AC 303,268) which is a lipophilic weak acid with very strong uncoupling activity ...

Chlorfenapyr is a member of a new class of chemicals- the pyrroles. The compound is a pro-insecticide, i.e. the biological activity depends on its activation to another chemical. Oxidative removal of the N-ethoxymethyl group of chlorfenapyr by mixed function oxidases forms the compound CL 303268. CL 303268 uncouples oxidative phosphorylation at the mitochondria, resulting in disruption of production of ATP, cellular death, and ultimately organism mortality.

Chlorfenapyr shows virtually no uncoupling activity but removal of the N-ethoxymethyl group through microsomal oxidation releases the corresponding free pyrrole (AC 303,268) which is a lipophilic weak acid with very strong uncoupling activity ... AC 302,268 has an acute toxicity higher than that of chlorfenapyr in both vertebrates and insects (eg, the acute oral LD50 for the rat is 29 mg/kg). Upon injection into insects it cause an almost immediate and massive stimulation of respiration whereas the parent chlorfenapyr does so only after a significant delay. All these observations support the idea that chlorfenapyr is a proinsecticide and requires metabolic conversion to the active uncoupler, AC 303,268, before it exert a toxic action.

[2-Pyrrole-14C]CL 303,630 or [Phenyl-(U)-14C]CL 303,630 (radiochemical,purity: 99-100%, S.A. 134.7 uCi/mg and 411.4 uCi/mg, respectively) and nonlabeled CL 303,630 (...98.8% purity) were suspended in 0.5% (w/w) CMC solution and administered via gavage to 5 rats/sex as single doses of 20.7 or 206.7 mg/kg and as multiple oral doses: pretreat 5 rats/sex daily with nonlabeled CL 303,630 for 14 days prior to pulsing with 20.5 mg/kg [2-Pyrrole-14C]CL 303,630 or [Phenyl-(U)-14C]CL 303,630. Regardless of treatment regimen, 14C CL 303,630 was eliminated mainly by the fecal route. By 48 hours, 70.4-91.4% and 3.9-9.7% of the administered radioactivity was detected in feces and urine, respectively. Blood and tissue concentrations were higher in females than in males indicating that there are substantial sex-related differences. The excreted fecal residue was mainly unchanged parent compound plus minor N-dealkylated, debrominated, and hydroxylated oxidation products. Absorbed CL 303,630 was extensively metabolized in tissues and urine by N-dealkylation, debromination, ring hydroxylation, and conjugation.

AC 303,268, and its further degradation products, is a common metabolites of chlorfenapyr found in studies with vertebrates ... Urinary metabolites /from an oral dose admin in rats/ included products of N-alkoxy side chain oxidation and removal (eg, AC 303,268) and ring hydroxylation products and their conjugates. Similar results were obtained with goats and hens. In fish and soil, debromination is observed as an additional metabolic route.

Organic nitriles are converted into cyanide ions through the action of cytochrome P450 enzymes in the liver. Cyanide is rapidly absorbed and distributed throughout the body. Cyanide is mainly metabolized into thiocyanate by either rhodanese or 3-mercaptopyruvate sulfur transferase. Cyanide metabolites are excreted in the urine. (L96)

An oral dose of chlorfenapyr was poorly absorbed in rats and over 80% was eliminated in the feces ...

Radioactive chlorfenapyr was administered to rats by oral gavage at dose levels of 20 mg/kg/day as a single dose or following a 14-day pre-treatment with non-radioactive chlorfenapyr, or at 200 mg/kg as a single dose. Based on the metabolites identified, the major deposition route of orally administered chlorfenapyr is fecal excretion of unaltered parent compound. The two rings of the molecule are not cleaved. Metabolites are excreted primarily in urine; accumulation in tissues is minimal.

Used as insecticide and acaricide as a foliar spray to ornamental crops in greenhouses; [HSDB] One of a new class of pro-insecticides, the pyrroles, that depend on activation to another chemical; [Reference #1]

Farming (Pesticides) [Category: Industry]

Insecticide, acaricide

For chlorfenapyr (USEPA/OPP Pesticide Code: 129093) 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./

For manufacturing use and as a foliar spray to ornamental crops in greenhouses. For greenhouse ornamentals /target pests include/ mites, caterpillar pests, thrips, and fungus gnats.

Acaricide, insecticide; For cotton, vegetables, citrus, and ornamentals. /Non-US/

Trade names include Alert, Citrex, Intrepid, Phantom, Pirate, Stalker, and Sunfire.

Trade Name: Pylon Miticide-Insecticide 21.4% chlorfenapyr

Suspension concentrate.

The WHO Recommended Classification of Pesticides by Hazard identifies Chlorfenapyr (technical grade) as Class II: moderately hazardous; Main Use: insecticide, miticide.

Chlorfenapyr ... was developed by structural modification of a microbial natural product, dioxapyrrolomycin ...