Methiocarb

Insecticides, Repellants

Active substance -> EU Pesticides database: Not approved

Pesticides -> Carbamate Insecticides

Molluscicides, Bird repellents, Insecticides

Environmental transformation -> Pesticides (parent, predecessor)

Pesticides -> Insecticides

log Kow = 2.92

3.08

2.8

Colorless crystals

White crystalline powder

200 g/l in dichloromethane; 53 g/l in isopropanol; 33 g/l in toluene; 1.3 g/l in hexane

In water, 27 mg/l @ 20 °C

Soluble in organic solvents.

Solubility in water, mg/l: 27

Very high. (USCG, 1999)

325 °C @760 [mm Hg]

When heated to decomposition it emits very toxic fumes of /nitrogen oxides & sulfur oxides/.

Hydrolysis DT50 (22 °C) >1 yr (pH 4), <35 day (pH 7), 6 hr (pH 9). Photodegradation contributes to the overall elimination of methiocarb from the environment; DT50 6-16 days.

243 °F (EPA, 1998)

119 °C

119 °C

Danger

H301: Toxic if swallowed [Danger Acute toxicity, oral]

P264, P270, P273, P301+P316, P321, P330, P391, P405, and P501 (click each P-code to see the statement)

Danger

H300+H330 (36.4%): Fatal if swallowed or if inhaled [Danger Acute toxicity, oral; acute toxicity, inhalation]

P260, P264, P270, P271, P273, P284, P301+P316, P304+P340, P316, P320, P321, P330, P391, P403+P233, P405, and P501 (click each P-code to see the statement)

Commission Regulation No 844/2012

07/5/EC, Reg. (EU) 2018/917, Reg. (EU) 2019/1606, Reg. (EU) 2019/707, Reg. (EU) No 187/2014, Reg. (EU) No 540/2011

Methiocarb: HSNO Approval: HSR002903 Approved with controls

The New Jersey Worker and Community Right to Know Act requires public and private employers to provide information about hazardous substances at their workplaces. (N.J.S.A. 34:5A-1 et. seq.)

When heated to decomposition, it emits very toxic fumes of nitrogen and sulfur oxides. (EPA, 1998)

Combustible. Finely dispersed particles form explosive mixtures in air.

As a carbamate insecticide, this compound is a reversible cholinesterase inhibitor and acts on the nervous system. It is classified as very toxic, and the probable oral lethal dose for humans is 50-500 mg/kg or between 1 teaspoon and 1 ounce for a 150 lb. adult. (EPA, 1998)

May cause skin and mucous membrane irritation; [HSDB] No malformations in rats or rabbits at 10 mg/kg/day, but caused malformations in chickens and ducks; [REPROTOX] A reversible cholinesterase inhibitor; [CAMEO] May cause irritation; A cholinesterase inhibitor; Can be absorbed through skin; A lachrymator; Effects in high-dose animal studies include convulsions; [MSDSonline] Contact dermatitis reported in a carnation grower; [Kanerva, p. 1812; PMID 9197969 ] See CARBAMATE INSECTICIDES.

USEPA/Office of Pesticide Programs; Reregistration Eligibility Decision Document - Methiocarb. The RED summarizes the risk assessment conclusions and outlines any risk reduction measures necessary for the pesticide to continue to be registered in the U.S.[Available from, as of April 30, 2003: http://www.epa.gov/pesticides/reregistration/status.htm]

[ As the federal pesticide law FIFRA directs, EPA is conducting a comprehensive review of older pesticides to consider their health and environmental effects and make decisions about their future use. Under this pesticide reregistration program, EPA examines health and safety data for pesticide active ingredients initially registered before November 1, 1984, and determines whether they are eligible for reregistration. In addition, all pesticides must meet the new safety standard of the Food Quality Protection Act of 1996. Methiocarb is found on List A, which contains most food use pesticides and consists of the 194 chemical cases (or 350 individual active ingredients) for which EPA issued registration standards prior to FIFRA, as amended in 1988. Case No: 0577; Pesticide type: Insecticide (Acaricide)(Molluscicide), Rodenticide (Bird Repellent); Registration Standard Date: 03/30/87; Case Status: RED Approved 02/94; OPP has made a decision that some/all uses of the pesticide are eligible for reregistration, as reflected in a Reregistration Eligibility Decision (RED) document.; Active ingredient (AI): Methiocarb; Data Call-in (DCI) Date(s): 03/30/94, 03/03/95; AI Status: OPP has completed a Reregistration Eligibility Decision (RED) document for the case/AI.

This compound is a solid carbamate insecticide.

In case of fire in the surroundings, use appropriate extinguishing media.

Fresh air, rest. Refer for medical attention.

Remove contaminated clothes. Rinse and then wash skin with water and soap. Refer immediately for medical attention.

Rinse with plenty of water (remove contact lenses if easily possible).

Rinse mouth. Refer immediately for medical attention.

Biological Exposure Indices (BEI) [ACGIH] - Acetylcholinesterase activity in red blood cells = 70% of individual's baseline; Butylcholinesterase activity in serum or plasma = 60% of individual's baseline; Sample at end of shift; [TLVs and BEIs]

A system for removing pesticides from the wash water produced by pesticide applicators as they clean their equipment has been developed. The first step is the flocculation/coagulation and sedimentation of the pesticide-contaminated wash water. The supernatant from the first step is then passed through activated carbon columns. /Pesticides/

[40 CFR 240-280, 300-306, 702-799 (7/1/2002)] Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number P199, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.

Generators of waste (= or >100 kg/mo) containing this contaminant, EPA hazardous waste number P199, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.

Group I Containers: Combustible containers from organic or metallo-organic pesticides (except organic mercury, lead, cadmium, or arsenic compounds) should be disposed of in pesticide incinerators or in specified landfill sites. /Organic or metallo-organic pesticides/

Group II Containers: Non combustible containers from organic or metallo-organic pesticides (except organic mercury, lead, cadmium, or arsenic compounds) must first be triple-rinsed. Containers that are in good condition may be returned to the manufacturer or formulator of the pesticide product, or to a drum reconditioner for reuse with the same type of pesticide product, if such reuse is legal under Department of Transportation regulations (eg 49 CFR 173.28). Containers that are not to be reused should be punctured ... and transported to a scrap metal facility for recycling, disposal or burial in a designated landfill. /Organic or metallo-organic pesticides/

DISSOLVE IN FLAMMABLE SOLVENT (SUCH AS ALCOHOL) & ATOMIZE IN SUITABLE COMBUSTION CHAMBER EQUIPPED WITH APPROPRIATE EFFLUENT GAS CLEANING DEVICE. /CARBARYL/

Personal protection: particulate filter respirator adapted to the airborne concentration of the substance. Do NOT let this chemical enter the environment. Sweep spilled substance into sealable containers. If appropriate, moisten first to prevent dusting. Then store and dispose of according to local regulations.

Protective clothing should be worn when working with undiluted preparations. Treated seeds should be kept away from foodstuffs, & should not be used as animal feed.

Keep all unprotected persons out of operating area or vicinity where there may be any danger of drift. Vacated areas should not be reentered for at least 2 days.

Smoking, eating, and drinking before washing should be absolutely prohibited when any pesticide of moderate or higher toxicity is being handled or used. /Pesticides/

If the compound has been ingested, rapid gastric lavage should be performed using 5% sodium bicarbonate. For skin contact, the skin should be washed with soap and water. If the compound has entered the eyes, they should be washed with large quantities of isotonic saline or water. In serious cases, atropine and/or pralidoxime should be administered. Anti-cholinergic drugs work to counteract the effects of excess acetylcholine and reactivate AChE. Atropine can be used as an antidote in conjunction with pralidoxime or other pyridinium oximes (such as trimedoxime or obidoxime), though the use of '-oximes' has been found to be of no benefit, or possibly harmful, in at least two meta-analyses. Atropine is a muscarinic antagonist, and thus blocks the action of acetylcholine peripherally.

... FEATURE OF INSECTICIDAL ACTION OF ... CARBAMATES /INCL MESUROL/ IS PRONOUNCED SYNERGISM SHOWN BY ADDITION OF METHYLENEDIOXY CMPD SUCH AS PIPERONYL BUTOXIDE, SESOXANE, & PROPYL ISOME ... THESE PREVENT IN VIVO DETOXICATION OF CARBAMATES BY INHIBITING "MIXED FUNCTION OXIDASE" DETOXIFICATION SYSTEM. /CARBAMATES/

... In an experiment using in vitro static diffusion cells mounted with human skin, ... the effect of nonylphenol-ethoxylate on dermal penetration of three extensively used pesticides--methiocarb, paclobutrazol, and pirimicarb... /was examined/ . There was a general tendency, though not statistically significant for all pesticides, for nonylphenolethoxylate to decrease the percutaneous penetration of the three pesticides.

Acute exposure to cholinesterase inhibitors can cause a cholinergic crisis characterized by severe nausea/vomiting, salivation, sweating, bradycardia, hypotension, collapse, and convulsions. Increasing muscle weakness is a possibility and may result in death if respiratory muscles are involved. Accumulation of ACh at motor nerves causes overstimulation of nicotinic expression at the neuromuscular junction. When this occurs symptoms such as muscle weakness, fatigue, muscle cramps, fasciculation, and paralysis can be seen. When there is an accumulation of ACh at autonomic ganglia this causes overstimulation of nicotinic expression in the sympathetic system. Symptoms associated with this are hypertension, and hypoglycemia. Overstimulation of nicotinic acetylcholine receptors in the central nervous system, due to accumulation of ACh, results in anxiety, headache, convulsions, ataxia, depression of respiration and circulation, tremor, general weakness, and potentially coma. When there is expression of muscarinic overstimulation due to excess acetylcholine at muscarinic acetylcholine receptors symptoms of visual disturbances, tightness in chest, wheezing due to bronchoconstriction, increased bronchial secretions, increased salivation, lacrimation, sweating, peristalsis, and urination can occur. Chronically high (>10 years) exposure leads to neuropsychological consequences including disturbances in perception and visuo-motor processing (A15321).

LD50 HOUSE SPARROW ORAL 18 MG/KG

LD50 HOUSE SPARROW PERCUTANEOUS MORE THAN 100 MG/KG

LD50 QUELEA ORAL 4.2 MG/KG

LD50 QUELEA PERCUTANEOUS 100 MG/KG

For more Ecotoxicity Values (Complete) data for METHIOCARB (24 total), please visit the HSDB record page.

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 920(SRC), determined from a measured log Kow of 2.92(2) and a regression-derived equation(3), indicates that methiocarb is expected to have low mobility in soil(SRC). Volatilization of methiocarb from moist soil surfaces is not expected to be an important fate process(SRC) given a Henry's Law constant of 1.18X10-9 atm-cu m/mole(4). Methiocarb is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 2.7X10-7 mm Hg(4). The half-life of methiocarb in soil was reported to range from 17 to 111 days under aerobic conditions(5). The photolysis half-life of methiocarb ranged from about 4-9 days on 3 soil surfaces(6). Hydrolysis is expected to be an important environmental fate process for methiocarb in soil, based on aqueous hydrolysis half-lives of 35 days and 6 hours at pH 7 and 9, respectively(4).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 920(SRC), determined from a measured log Kow of 2.92(2) and a regression-derived equation(3), indicates that methiocarb is expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is not expected(3) based upon a Henry's Law constant of 1.18X10-9 atm-cu m/mole(4). According to a classification scheme(5), an estimated BCF of 35(SRC), from its log Kow(2) and a regression-derived equation(6), suggests the potential for bioconcentration in aquatic organisms is moderate(SRC). Hydrolysis is expected to be an important environmental fate process for methiocarb, with half-lives of 35 days and 6 hours at pH 7 and 9, respectively(4).Photolysis in sunlit surface water may also be an important fate process for methiocarb(SRC). The photolysis half-life of methiocarb in river water exposed to UV light (286-400 nm) was approximately 23 minutes(7).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), methiocarb, which has a vapor pressure of 2.7X10-7 mm Hg at 25 °C(2), is expected to exist in both the vapor and particulate phases in the ambient atmosphere. Vapor-phase methiocarb 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 29 hours(SRC), calculated from its rate constant of 1.35X10-11 cu cm/molecule-sec at 25 °C(SRC) determined using a structure estimation method(3). Particulate-phase methiocarb may be removed from the air by wet and dry deposition(SRC). Methiocarb absorbs light in the environmental UV spectrum and has a photolysis half-life in the range of 6-16 days(2).

Methiocarb has been applied to wine grapes in Australia, Ohio, California, & Oregon, & to blueberries in New Zealand. Residues were reported in wine, & its effect on the composition & flavor of the bottled wine was reported.

Methiocarb was detected in peppers and raddish at concns of 0.5 ppm(1). Methiocarb was detected in 2.5% of peppers (0.028 ppm, mean value), 1.1% of radishes (0.033 ppm, mean value) and, 1.4% of strawberries (0.052 ppm, mean value)(2).

The substance can be absorbed into the body by ingestion and through the skin.

Inhalation (L793) ; oral (L793); dermal (L793)

Methiocarb is a cholinesterase or acetylcholinesterase (AChE) inhibitor. Carbamates form unstable complexes with chlolinesterases by carbamoylation of the active sites of the enzymes. This inhibition is reversible. A cholinesterase inhibitor suppresses the action of acetylcholine esterase. Because of its essential function, chemicals that interfere with the action of acetylcholine esterase are potent neurotoxins, causing excessive salivation and eye-watering in low doses. Headache, salivation, nausea, vomiting, abdominal pain and diarrhea are often prominent at higher levels of exposure. Acetylcholine esterase breaks down the neurotransmitter acetylcholine, which is released at nerve and muscle junctions, in order to allow the muscle or organ to relax. The result of acetylcholine esterase inhibition is that acetylcholine builds up and continues to act so that any nerve impulses are continually transmitted and muscle contractions do not stop.

The average daily intake (AVDI) for methiocarb in Belgium from 1991-1993 was estimated as 0.001 mg/kg/day using a total diet survey(1). The AVDI of methiocarb in ng/kg/day in the following US population as determined from a total diet survey (1982-1984) is: 6-11 month infants, 0.1; 2 year old children, 0.4; 14-16 year old females, no consumption of foods containing methiocarb; 14-16 year old males, no consumption of foods containing methiocarb; 25-30 year old females, no consumption of foods containing methiocarb; 25-30 year old males, no consumption of foods containing methiocarb; 60-65 year old females, no consumption of foods containing methiocarb; 60-65 year old males, no consumption of foods containing methiocarb(2).

/BIRDS and MAMMALS/ Lethal and sublethal doses of carbamate pesticides incl methiocarb were admin to Japanese quail. No birds surviving the carbamate treatments at 24 hr showed a significant inhibition of brain acetylcholinesterase, and birds surviving doses of methiocarb showed elevated plasma esterase levels. After 24 hr, incr in plasma glutamate oxaloacetate transaminase levels were observed in survivors from treatments with the pesticides aldicarb, methiocarb, oxamyl, pirimicarb and thiofanox. Lethal doses of carbamates gave a >65% inhibition of plasma acetylcholinesterase and a >75% inhibition of plasma cholinesterase. Plasma esterase activities at 24 hr after dosing generally returned to control levels or above. Lethal doses of carbamates produced 40-60% inhibition of brain acetylcholinesterase.

/BIRDS and MAMMALS/ Two physiological responses (heart rate and respiration rate) and a behavioral response (keypecking rate) were measured to determine whether or not bait form and/or gastrointestinal content would influence the efficacy of an avian repellent on red-winged blackbirds (Agelaius phoeniceus). Both physiological and behavioral responses to methiocarb are much more pronounced when it is admin in pellet form to food-deprived birds.

/BIRDS and MAMMALS/ Methiocarb (4-methylthio-3, 5-xylyl N-methyl carbamate, Mesurol, Bay (3744), a bird repellent, was fed in concns of 100 to 1,000 ppm to common grackles (Quiscalus quiscula), mourning doves (Zenaida macroura), and breeding pairs of coturnix quail (Coturnix coturnix) to investigate the possibility of cumulative intoxication. Although aversion to treated diets was readily apparent in most of the tests, the 28- to 30-day median lethal concentration (LC50) was determined to be >100 ppm for grackles, 630 ppm (95% confidence limits, 480-830 ppm) for doves, and >1,000 ppm for coturnix quail. Methiocarb appeared to be noncumulative when measured by an index of chronicity: birds consumed several LD50 doses during a day's feeding, and when deaths occurred, they appeared to be due to acute intoxication. Egg production and live chick production were not affected in coturnix fed 100 ppm but were reduced at 316 and 1,000 ppm. ...Results suggest that under field conditions it would be impossible for birds to consume a lethal dose.

/OTHER TERRESTRIAL SPECIES/ Two trials were carried out to test the effects of field applications of snail baits on populations of house mice (Mus domesticus) inhabiting cereal-cropping fields during a mouse plague in South Australia. In the first trial, grain based pellets containing 2% w/w active ingredient methiocarb, were laid in trails across fields before crops were sown. The second tested the effect of whole wheat grains treated with 1% w/w methiocarb when broadcast across maturing barley crops. Treatment effects were estimated by comparison with untreated control plots. In the methiocarb-treated wheat trial, comparison was also made with 0.3% w/w strychnine-treated wheat treatments. Methiocarb baiting reduced estimated mouse numbers by 0-46%. Surviving mice did not accept the excess bait material available. In contrast, strychnine-treated wheat reduced estimated mouse numbers by 86-94%. These trials indicate that methiocarb is not likely to be a useful field rodenticide. Furthermore, the consumption of bait by mice is not likely to jeopardise snail control operations. However, methiocarb baits could cause sufficient mortality to pose a threat to rare or endangered granivorous rodents inhabiting agricultural fields.

For more Ecotoxicity Excerpts (Complete) data for METHIOCARB (6 total), please visit the HSDB record page.

Cough.

MAY BE ABSORBED!

Pupillary constriction. Watering of the eyes.

Excessive salivation. Blurred vision. Sweating. Headache. Vomiting. Diarrhoea. Convulsions. Unconsciousness.

As with organophosphates, the signs and symptoms are based on excessive cholinergic stimulation. Unlike organophosphate poisoning, carbamate poisonings tend to be of shorter duration because the inhibition of nervous tissue acetylcholinesterase is reversible, and carbamates are more rapidly metabolized. Muscle weakness, dizziness, sweating and slight body discomfort are commonly reported early symptoms. Headache, salivation, nausea, vomiting, abdominal pain and diarrhea are often prominent at higher levels of exposure. Contraction of the pupils with blurred vision, incoordination, muscle twitching and slurred speech have been reported. (L795)

[ As the federal pesticide law FIFRA directs, EPA is conducting a comprehensive review of older pesticides to consider their health and environmental effects and make decisions about their future use. Under this pesticide reregistration program, EPA examines health and safety data for pesticide active ingredients initially registered before November 1, 1984, and determines whether they are eligible for reregistration. In addition, all pesticides must meet the new safety standard of the Food Quality Protection Act of 1996. Methiocarb is found on List A, which contains most food use pesticides and consists of the 194 chemical cases (or 350 individual active ingredients) for which EPA issued registration standards prior to FIFRA, as amended in 1988. Case No: 0577; Pesticide type: Insecticide (Acaricide)(Molluscicide), Rodenticide (Bird Repellent); Registration Standard Date: 03/30/87; Case Status: RED Approved 02/94; OPP has made a decision that some/all uses of the pesticide are eligible for reregistration, as reflected in a Reregistration Eligibility Decision (RED) document.; Active ingredient (AI): Methiocarb; Data Call-in (DCI) Date(s): 03/30/94, 03/03/95; AI Status: OPP has completed a Reregistration Eligibility Decision (RED) document for the case/AI.

Persons in charge of vessels or facilities are required to notify the National Response Center (NRC) immediately, when there is a release of this designated hazardous substance, in an amount equal to or greater than its reportable quantity of 10 lb or 4.54 kg. The toll free number of the NRC is (800) 424-8802; In the Washington D.C. metropolitan area (202) 426-2675. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV. D.3.b).

Releases of CERCLA hazardous substances are subject to the release reporting requirement of CERCLA section 103, codified at 40 CFR part 302, in addition to the requirements of 40 CFR part 355. Methiocarb is an extremely hazardous substance (EHS) subject to reporting requirements when stored in amounts in excess of its threshold planning quantity (TPQ) of 500 or 10,000 lbs. Extremely hazardous substances that are solids are subject to either of two threshold planning quantities ... The lower quantity applies only if the solid exists in powdered form and has a particle size less than 100 microns; or is handled in solution or in molten form; or meets the criteria for a National Fire Protection Association (NFPA) rating of 2, 3 or 4 for reactivity. If the solid does not meet any of these criteria, it is subject to the upper ... threshold planning quantity ... .

The carbamate insecticides are reversible cholinesterase-inhibitors. They cause this effect by reversible carbamylation of the enzyme acetylcholinesterase, allowing accum of acetylcholine, as with the organophosphate insecticides. ... While the organophosphate insecticides cause irreversible inhibition of the cholinesterase enzymes, the carbamyl-enzyme complex is reversible & dissociates far more readily than the organophosphate complex. The clinical syndrome is more benign & of much shorter duration with the carbamate insecticides. /Carbamate insecticides/

The effects of methiocarb on the acetylcholinesterase activity of bovine erythrocytes & butyrylcholinesterase from equine plasma were examined in vitro. The enzyme soln was mixed with methiocarb & incubated at 2 °C & aliquots were withdrawn at precise intervals for the determination of inhibited reaction rate. Dissociation constants of enzyme-carbamate complexes (Kd) & the rate constants of enzyme carbamoylation (K2) were also determined. The Kd & K2 values for the inhibition of bovine erythrocyte AChE by methiocarb at concn of 2.5 x 10-5, 2.5 x 10-4, & 2.5 x 10-3 moles/l were 3.8 x 10-4, 4.4 x 10-4, & 5.0 x 10-4 moles/l, & 1.87, 1.18, & 1.06/min, respectively. The Kd & K2 values for the inhibition of equine plasma butyrylcholinesterase by methiocarb at concn of 2.5 x 10-4 & 2.5 x 10-3 moles/l were 1.0 x 10-3 & 8.2 x 10-4 moles/l & 1.21 & 1.13/min, respectively.

The anticholinesterase (antiCHE) insecticides... inhibit serine hydrolases by carbamylating or phosphorylating a serine residue at the catalytic site. These insecticides are viewed as potential inhibitors of serine hydrolase-dependent immune functions including interleukin 2 (IL2) signalling.

WHEN RAT & HUMAN LIVER WAS INCUBATED WITH MESUROL, ABOUT A DOZEN METABOLITES WERE OBSERVED ... MAJOR METABOLITE WAS MESUROL SULFOXIDE. SEVERAL METABOLIC PRODUCTS ... FROM HUMAN LIVER STUDIES, WERE NOT OBSERVED IN RAT STUDIES. HYDROLYSIS YIELDED THE PHENOLIC MOIETY OF MESUROL.

Methiocarb, an aromatic alkyl sulfide insecticide was enzymatically oxidized into sulfoxide by microsomes from soybean cotyledons. No further oxidation into sulfone was detected. Distribution of the sulfoxidase activity was studied in soybean seedlings & was maximal in cotyledons. Subcellular fractionation of cotyledon homogenates indicated that the activity was almost entirely associated with the microsomal fraction. Methiocarb did not require cofactors such as NAD(P)H. Nevertheless, the sulfoxidase did not act as a peroxidase.

The oxidation of sulfide-containing organophosphate & carbamate pesticides by the flavin-containing monooxygenase was measured in mammalian microsomes made devoid of cytochrome p450 dependent activity, primarily through the use of inhibitory antibodies against reduced nicotinamide adenine dinucleotide phosphate cytochrome p450 reductase. Rates of metab were determined for mouse, rabbit & rat liver, lung & kidney microsomes, & for pig liver microsomes. Substrate specificity of the enzyme in different species & tissues is similar. Lung & kidney microsomes have high flavin-containing monooxygenase levels, & this enzyme is important relative to cytochrome p450 in these tissues. Thioether-containing organophosphates are effective substrates for the flavin-containing monooxygenase in mouse liver microsomes, with Km values between 3.5 & 36 muM. Thioether-containing carbamates are less effective substrates having Km values near 280 muM. ... /Thioether-containing organophosphate & carbamate pesticides/

The ability of purified microsomal FAD-containing monooxygenase from mouse & pig liver to oxidize pesticides was investigated. The kinetic constants were determined for a number of pesticide substrates including thioether-containing organophosphorus cmpds, carbamates /thiofanox, methiocarb, aldicarb/ & (di)alkyldithiocarbamates. The thioether-containing organophosphorus cmpds were the best substances for both enzymes followed by the thioether-containing carbamates. The (di)alkyldithiocarbamates were relatively poor substrates for both pig & mouse liver microsomal FAD-containing monooxygenases.

For more Metabolism/Metabolites (Complete) data for METHIOCARB (8 total), please visit the HSDB record page.

The carbamates are hydrolyzed enzymatically by the liver; degradation products are excreted by the kidneys and the liver. (L793)

Pesticides designed to control insects that are harmful to man. The insects may be directly harmful, as those acting as disease vectors, or indirectly harmful, as destroyers of crops, food products, or textile fabrics.

Agents destructive to snails and other mollusks.

In dermal toxicity studies, methiocarb was not readily absorbed via the skin, even in solvents expected to enhance dermal absorption. In a cow given 5 daily doses of ring-labeled methiocarb, radioactivity in the milk (due to methiocarb sulfoxide) peaked at 0.062 ppm after the third dose. Tissue residues were highest in the kidney (0.108 ppm) & liver (0.073 ppm); levels in other tissues did not exceed 0.02 ppm. Following subchronic dietary exposure of beef & dairy cattle to methiocarb, residues exceeded 0.005 ppm only in the liver (at dosages of 30 ppm or higher) & the kidney (at a dosage of 100 ppm); residues were not detected in the brain, heart, muscle, or fat. Milk collected on exposure days 28 & 29 contained methiocarb residues ranging from 0.005 ppm (at a dosage of 10 ppm) to 0.033 ppm (at a dosage of 100 ppm).

Of a single dose of carbonyl-labeled methiocarb to rats, more than 60% was eliminated as expired 14 CO2. In another study, about 66% was eliminated as 14 CO2, about 22% in the urine, & 2.5% in the feces; elimination was about 91% complete. Ring-labeled methiocarb was excreted almost entirely in the urine within 48 hr. Of a ring-labeled dose of methiocarb to a dairy cow, 96% appeared in the urine, 1% in the feces, and 1% in the milk within 144 hr.

In dogs & mice, following oral admin, methiocarb is rapidly absorbed & excreted, principally in the urine, with only a small proportion in the feces.

Used as insecticide, acaricide, molluscicide, and bird repellent; [HSDB] Used as insecticide, acaricide, and molluscicide on lawns, turf, ornamentals, around buildings, in greenhouses, and in ginseng gardens (12-month preharvest interval so not considered a food use); [Reference #2]

Farming (Pesticides) [Category: Industry]

For Methiocarb (USEPA/OPP Pesticide Code: 100501) 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./

Acaricide; molluscicide

Controls slugs, snails in a wide range of crops; controls sucking & biting insects (including soil insects) & spider mites in beets, berries, citrus, hops, maize, oilseed rape, ornamentals, pome & stone fruit, potatoes, vegetables; also used as a bird repellent.

IT IS PARTICULARLY EFFECTIVE FOR CONTROL OF MITES, INCLUDING PHOSPHATE RESISTANT STRAINS, AT RELATIVELY LOW RATES

Methiocarb may be made by the reaction of methyl isocyanate with 4-methylthio-3,5-xylenol.

BY CONDENSATION OF 4-METHYLTHIO-3,5-XYLENOL WITH ... PHOSGENE & METHYLAMINE.

USEPA/OPP Pesticide Code 100501; Trade Names: Mesurol, BAY 37344, ENT-25726, H 321, Draza.

... INCLUDE: 'MESUROL', WETTABLE POWDERS (500 & 750 G ACTIVE INGREDIENT/KG); DUST (30 G/KG); 'DRAZA', PELLETS FOR SLUG CONTROL (40 G/KG).

Bait, granules, suspension concentrate & wettable powder. Dry seed dressing. Flowable seed treater concentrate & water-dispersible granules.

Methiocarb is formulated as a wettable powder, liquid, seed dressing, bait, & hopper box treater.

Trade Names: Draza, Baysol (Bayer)

Pesticides -> Insecticides

Molluscicides, Bird repellents, Insecticides

Environmental transformation -> Pesticides (parent, predecessor)

INSECTICIDES

The WHO Recommended Classification of Pesticides by Hazard identifies Methiocarb (technical grade) as Class IB: highly hazardous; Main Use: insecticide.

IT IS A NON-SYSTEMIC INSECTICIDE & ACARICIDE WITH A BROAD RANGE OF ACTION & GOOD RESIDUAL ACTIVITY, USED AT 50-100 G ACTIVE INGREDIENT/100 L. IT IS ... A POWERFUL MOLLUSCICIDE USED AS PELLETS AT 200 G ACTIVE INGREDIENT/HECTARE; AND BIRD REPELLENT WHEN USED AS SEED TREATMENT. ... IT WAS INTRODUCED IN 1962 BY BAYER AG UNDER THE CODE NUMBERS 'BAYER 37 344', 'H 321', THE TRADE MARKS 'MESUROL' & 'DRAZA' & PROTECTED BY FRENCH PATENT 1,275,658; DEP 1,162,352.

EXPERIMENTAL, IN CONTROL OF FACE FLIES ON CATTLE (1% SPRAY-6 HR PROTECTION), & AS TEMPORARY IMMOBILIZING AGENT FOR BIRDS (ORAL-LESS THAN 10 MG/KG).

A 0.5% methiocarb + 1% wattle tannin provided protection to sorghum, millet, and wheat from bird damage.