Absorption, Distribution and Excretion
... NOT ABSORBED THROUGH SKIN TO ANY APPRECIABLE EXTENT ... . /2,4-D/
(14)C MCPA ... INJECTED IV INTO PREGNANT MICE, WHICH WERE THEN STUDIED BY AUTORADIOGRAPHY AT INTERVALS OF 5 MIN TO 72 HR. DISTRIBUTION PATTERN WAS CHARACTERIZED BY HIGH CONCN IN BLOOD UP TO 4 HR & ACCUMULATION IN VISCERAL YOLK SAC EPITHELIUM UP TO 24 HR AFTER INJECTION. RADIOACTIVE SUBSTANCE PASSED THE PLACENTA, BUT FETAL TISSUES NEVER REACHED CONCN OF THE MATERNAL TISSUES. RADIOACTIVITY WAS ELIMINATED FROM FETUSES & MOTHERS BY 24 HR AFTER INJECTION.
WHEN ADMINISTERED TO RATS BY STOMACH TUBE, THE HIGHEST CONCENTRATIONS OF (14)C MCPA IN THE TISSUES WAS REACHED IN 2-8 HR & THEN DECLINED RAPIDLY. DURING THE FIRST 24 HOURS 92.3% OF THE DOSE WAS DISCOVERED IN URINE & 6.8% IN THE FECES.
ABOUT 50% OF THE TOTAL DOSE WAS DETECTED IN URINE OF 4 VOLUNTEERS WITHIN 48 HR AFTER EACH INGESTED 5 MG OF MCPA. FIVE DAYS AFTER INGESTION, THE CONCENTRATION IN THE URINE WAS BELOW THE DETECTABLE LEVEL OF 0.02 PPM.
For more Absorption, Distribution and Excretion (Complete) data for 2-METHYL-4-CHLOROPHENOXYACETIC ACID (8 total), please visit the HSDB record page.

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Metabolism / Metabolites
YIELDS 4-CHLORO-2-HYDROXYMETHYLPHENOXYACETIC ACID & N-(4-CHLORO-2-METHYLPHENOXYACETYL)-L-ASPARTIC ACID IN RAPE & IN CAMPION. YIELDS 4-CHLORO-2-METHYLPHENOXYACETYL-BETA-D-GLUCOSE PROBABLY IN RAPE. /FROM TABLE/
... 2-METHYL-4-CHLOROPHENOL WAS DETECTED IN MILK OF DAIRY COWS & IN KIDNEYS OF SHEEP & CATTLE.
ARTHROBACTER SP AND FLAVOBACTERIUM PEREGRINUM DEGRADED MCPA TO 4-CHLORO-2-METHYLPHENOL. FLAVOBACTERIUM FURTHER OXIDIZED PHENOL TO RELEASE ALL CHLORIDE. ASPERGILLUS NIGER VAN TIEGH ALSO METABOLIZED MCPA TO 4-CHLORO-2-METHYL-5-HYDROXYPHENOXYACETIC ACID.
... GRAM-NEGATIVE SOIL BACTERIUM METABOLIZED MCPA TO 5-CHLORO-O-CRESOL, A COMPOUND BELIEVED TO BE 6-HYDROXY-MCPA & ALPHA-METHYL-GAMMA-CARBOXYMETHYLENE-DELTA ALPHA-BUTENOLIDE.
For more Metabolism/Metabolites (Complete) data for 2-METHYL-4-CHLOROPHENOXYACETIC ACID (6 total), please visit the HSDB record page.
CDDs are absorbed through oral, inhalation, and dermal routes of exposure. CDDs are carried in the plasma by serum lipids and lipoproteins, distributing mainly to the liver and adipose tissue. CDDs are very slowly metabolized by the microsomal monooxygenase system to polar metabolites that can undergo conjugation with glucuronic acid and glutathione. They may increase the rate of their own metabolism by inducing CDDs induce both phase I and phase II enzymes. The major routes of excretion of CDDs are the bile and the feces, though smaller amounts are excreted in the urine and via lactation. (L177)

[1]. Sorption and desorption of glyphosate, MCPA and tetracycline and their mixtures in soil as influenced by phosphate. J Environ Sci Health B. 2017 Dec 2;52(12):887-895.

[2]. Biodegradable PBAT/PLA Blend with Bioactive MCPA-PHBV Conjugate Suppresses Weed Growth. Biomacromolecules. 2018 Feb 12;19(2):511-520.

(4-chloro-2-methylphenoxy)acetic acid is a chlorophenoxyacetic acid that is (4-chlorophenoxy)acetic acid substituted by a methyl group at position 2. It has a role as a synthetic auxin, an environmental contaminant and a phenoxy herbicide. It is a chlorophenoxyacetic acid and a member of monochlorobenzenes.
2-methyl-4-chlorophenoxyacetic acid or MCPA is a powerful, selective, widely used phenoxy herbicide. It controls broadleaf weeds, including thistle and dock, in cereal crops and pasture. It is selective for plants with broad leaves, and this includes most deciduous trees. Clovers are tolerant at moderate application levels. It is currently classified as a restricted use pesticide in the United States.
A powerful herbicide used as a selective weed killer.

C9H9CLO3

200.61

200.024

94-74-6

MCPA-d3;352431-14-2;MCPA-13C8

7204

Light yellow to yellow solid powder

1.3±0.1 g/cm3

327.0±27.0 °C at 760 mmHg

114-118 °C(lit.)

151.6±23.7 °C

0.0±0.7 mmHg at 25°C

1.552

2.49

1

3

3

13

184

0

WHKUVVPPKQRRBV-UHFFFAOYSA-N

InChI=1S/C9H9ClO3/c1-6-4-7(10)2-3-8(6)13-5-9(11)12/h2-4H,5H2,1H3,(H,11,12)

2-(4-chloro-2-methylphenoxy)acetic acid

Raphone; Krezone; MCPA

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: This product requires protection from light (avoid light exposure) during transportation and storage.

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

DMSO : ~50 mg/mL (~249.23 mM)

Solubility in Formulation 1: ≥ 2.5 mg/mL (12.46 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
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.

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Solubility in Formulation 2: ≥ 2.5 mg/mL (12.46 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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