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

Toxicity Summary
Metolcarb 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.

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Toxicity Data
LC50 (rat) = 475 mg/m3

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Interactions
The combined toxicity of malathion, 2-sec-butylphenylmethylcarbamate, m-tolymethylcarbamate, and 3,4-xylyl-methylcarbamate was studied in mice and rats. ICR mice and male Fischer 344 rats were exposed orally to a suspension of insecticides at five dose concentrations to determine the median lethal dose (LD50); animals were observed for mortality at least 7 days after dosing. ... Mice were killed, brains were homogenized, and brain acetylcholinesterase activity was determined. Of all combinations tested, only malathion plus 2-sec-butylphenylmethylcarbamate exhibited a marked synergism in acute toxicity in male mice; other combinations with m-tolymethylcarbamate, or 3,4-xylyl-methylcarbamate did not show any significant potentiation of toxicity in male mice. Female mice responded similarly to insecticide synergism. In rats, the synergism was relatively less potent than in mice. Symptoms of muscle fasciculation, increased salivation, urination, convulsion, and dyspnea were similar in mice and rats. Significant time differences in mortality after dosing were observed among the insecticides and between rats and mice. ...
Succinylcholine, other cholinergic agents, and aminophylline are contraindicated. /Carbamates and related compounds/

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Non-Human Toxicity Values
LD50 Rat male oral 580 mg/kg
LD50 Rat female oral 498 mg/kg
LD50 Mouse oral 109 mg/kg
LD50 Rat percutaneous >2,000 mg/kg
For more Non-Human Toxicity Values (Complete) data for METOLCARB (6 total), please visit the HSDB record page.

[1]. Jingwei Sun, et al. Development of enzyme linked immunoassay for the simultaneous detection of carbaryl and metolcarb in different agricultural products. Anal Chim Acta. 2010 May 7;666(1-2):76-82.

Metolcarb is a colorless crystalline solid. Metolcarb is an insecticide for the control of rice leafhoppers, planthoppers, codling moth, citrus mealybug, onion thrips, fruit flies, bollworms and aphids. Not registered as a pesticide in the U.S. (EPA, 1998)
Metolcarb is a carbamate ester. It has a role as an EC 3.1.1.7 (acetylcholinesterase) inhibitor, a carbamate insecticide, an acaricide and an agrochemical. It is functionally related to a methylcarbamic acid and a m-cresol.
Metolcarb is a synthetic carbamate ester compound and acetylcholinesterase inhibitor that is used as a pesticide. It is characterized as a colorless crystalline solid, and exposure occurs by inhalation, ingestion, or contact.
Metolcarb is a carbamate pesticide. Carbamate pesticides are derived from carbamic acid and kill insects in a similar fashion as organophosphate insecticides. They are widely used in homes, gardens and agriculture. The first carbamate, carbaryl, was introduced in 1956 and more of it has been used throughout the world than all other carbamates combined. Because of carbaryl's relatively low mammalian oral and dermal toxicity and broad control spectrum, it has had wide use in lawn and garden settings. Most of the carbamates are extremely toxic to Hymenoptera, and precautions must be taken to avoid exposure to foraging bees or parasitic wasps. Some of the carbamates are translocated within plants, making them an effective systemic treatment. (L795)

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Mechanism of Action
Cholinesterase inhibitor.

C9H11NO2

165.19

165.078

1129-41-5

Metolcarb-d3;1777782-68-9

14322

Colorless crystalline solid

1.1±0.1 g/cm3

241.6±23.0 °C at 760 mmHg

74-77 °C

99.9±22.6 °C

0.0±0.5 mmHg at 25°C

1.517

1.63

1

2

2

12

159

0

CC1=CC(OC(NC)=O)=CC=C1

VOEYXMAFNDNNED-UHFFFAOYSA-N

InChI=1S/C9H11NO2/c1-7-4-3-5-8(6-7)12-9(11)10-2/h3-6H,1-2H3,(H,10,11)

(3-methylphenyl) N-methylcarbamate

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)