4-Chloro-2-methylphenol

Environmental transformation -> Pesticide transformation products (metabolite, successor)

Pesticide degradation product

log Kow = 2.78

3.09

1.2 g/cu cm

0.48 g/cm³

Needles from petroleum ether

Pale yellow solid

less than 1 mg/mL at 59 °F (NTP, 1992)

Sol in petroleum ether

In water, 4.00X10+3 mg/l @ 25 °C

Solubility in water, g/100ml at 20 °C: 0.23

greater than 235 °F (NTP, 1992)

78 °C

432 to 437 °F at 760 mmHg (NTP, 1992)

223 °C

231 °C

Danger

H314: Causes severe skin burns and eye damage [Danger Skin corrosion/irritation]

P260, P261, P264, P271, P273, P280, P301+P330+P331, P302+P361+P354, P304+P340, P305+P354+P338, P316, P321, P363, P391, P403+P233, P405, and P501 (click each P-code to see the statement)

Danger

H314 (100%): Causes severe skin burns and eye damage [Danger Skin corrosion/irritation]

P260, P261, P264, P264+P265, P271, P273, P280, P301+P330+P331, P302+P361+P354, P304+P340, P305+P354+P338, P316, P317, P319, P321, P363, P391, P403+P233, P405, and P501 (click each P-code to see the statement)

Chemical: Phenol, 4-chloro-2-methyl-

Status: Active Update: 29-03-2021 https://echa.europa.eu/registration-dossier/-/registered-dossier/1917

4-Chloro-2-cresol: Does not have an individual approval but may be used under an appropriate group standard

This chemical is probably combustible. (NTP, 1992)

Combustible.

A skin, eye, and mucous membrane irritant; [CAMEO] A corrosive substance that can cause injury to the skin and eyes, based on animal studies; [CHEMINFO] A corrosive substance that can cause injury to the skin, eyes, and respiratory tract; Can cause pulmonary edema; [ICSC] Chlorocresol causes contact urticaria (both immune and non-immune); [Kanerva, p. 219] A corrosive substance that can cause injury to the skin, eyes, and respiratory tract; Inhalation may cause chemical pneumonitis; [MSDSonline] See CHLOROPHENOLS. See p-Chloro-m-cresol.

USEPA; Ambient Water Quality Criteria Doc: Chlorinated Phenols (1980) EPA 440/5-80-032.

Nat'l Research Council Canada; Chlorinated Phenols (1982) NRCC No. 18578

BIBRA working group; TA: Toxicity profile. BIBRA Toxicology Intl: 7 (1992).

Gesellschaft Deutscher Chemiker (GDCh) - Advisory Committee on Existing Chemicals of Environmental Relevance (BUA). S. Hirzel Verlag, P.O. Box 10 10 61, 70009 Stuttgart, Germany (1995).

P-CHLORO-O-CRESOL can react vigorously with concentrated sodium hydroxide solutions. Also reacts with other bases, acid chlorides, acid anhydrides, and oxidizing agents. Corrodes steel, brass, copper and copper alloys [NTP, 1992)]. A large quantity left in contact with concentrated sodium hydroxide solution for 3 days reacted violently, attaining red heat and evolving fumes that ignited explosively. The heat of reaction dissipated poorly because of the high viscosity of the mixture [Quart. Safety Summ., 1957, 28, 39].

Fires involving this material can be controlled with a dry chemical, carbon dioxide or Halon extinguisher. (NTP, 1992)

Use water spray, foam, dry powder, carbon dioxide.

Fresh air, rest. Half-upright position. Artificial respiration may be needed. Refer for medical attention.

Remove contaminated clothes. Rinse skin with plenty of water or shower. Refer for medical attention .

First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.

Rinse mouth. Give one or two glasses of water to drink. Do NOT induce vomiting. Refer for medical attention .

EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.

Gamma-ray-induced degradation on nonbiodegradable organic compounds is demonstrated on chlorophenols and 4-chlorocresol. The oxidation in aqueous solutions with air at doses up to 1 Mrad results in complete dechlorination. The following organic compounds have been identified in the case of 4-chlorocresol as oxidation products: oxalic acid, formic acid (HCO2H), acetic acid (HOAC), glyoxal, mesoxalic acid, mesoxalic acid semialdehyde.

Activated carbon adsorption was used for spill cleanup in the manufacture of chlorinated pesticides, including 4-chloro-2-methylphenol.

Activated carbon is a good method for removing chlorophenols from water. Competitive adsorption occurs between chlorophenols and humic substances present in nearly all municipal water supplies. This competition decreases the capacity of carbon for chlorophenols. /Chlorophenols/

SMALL SPILLS AND LEAKAGE: Should a spill occur while you are handling this chemical, FIRST REMOVE ALL SOURCES OF IGNITION, then you should dampen the solid spill material with 60-70% ethanol and transfer the dampened material to a suitable container. Use absorbent paper dampened with 60-70% ethanol to pick up any remaining material. Seal the absorbent paper, and any of your clothes, which may be contaminated, in a vapor-tight plastic bag for eventual disposal. Solvent wash all contaminated surfaces with 60-70% ethanol followed by washing with a soap and water solution. Do not reenter the contaminated area until the Safety Officer (or other responsible person) has verified that the area has been properly cleaned.

SRP: At the time of review, criteria for land treatment or burial (sanitary landfill) disposal practices are subject to significant revision. Prior to implementing land disposal of waste residue (including waste sludge), consult with environmental regulatory agencies for guidance on acceptable disposal practices.

The environmentally hazardous organic substances /including 4-chloro-2-methylphenol/ in the waste water from the manufacture of chlorophenoxyalkanoic acids were identified and semiquantified before & after passing through a biological treatment plant for municipal sewage, the secondary effluent of which was discharged into a marine ecosystem. The removal of chlorophenols was good, with a 90% overall reduction of chlorinated substances in the sewage passing through the treatment plant.

Consult an expert! Personal protection: chemical protection suit including self-contained breathing apparatus. Sweep spilled substance into covered containers. If appropriate, moisten first to prevent dusting. Do NOT let this chemical enter the environment.

TERRESTRIAL FATE: Based on a classification scheme(1), Koc values of 124 to 645(2), indicate that 4-chloro-2-methylphenol is expected to have moderate mobility in soil(SRC). Volatilization of 4-chloro-2-methylphenol from moist soil surfaces is expected to be an important fate process(SRC) given a Henry's Law constant of 1.1X10-6 atm-cu m/mole(3). 4-Chloro-2-methylphenol is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 2.40X10-2 mm Hg(3). 4-Chloro-2-methylphenol was almost completely degraded from 2 natural soils treated at 10 ppm within an 8 week incubation period at 25 °C, while nearly a 90 percent reduction occurred after 4 weeks time(4). At a concentration of 200 and 2000 ppm, 12 weeks were required to achieve an approximate 95 percent reduction of initial substrate(4). 4-Chloro-2-methylphenol was degraded similarly in sandy clay and silty clay soils(5). Half-lives were 21 days in both types of soil at initial concentrations of 10 and 1000 ppm each(5). The first order rate constant for the degradation of 3-methyl-4-chlorophenol was 0.0337 in sandy clay soil and 0.0334 in silty clay soil(5). Thus, 4-chloro-2-methylphenol is expected to biodegrade in soil.

AQUATIC FATE: Based on a classification scheme(1), Koc values of 124 to 645(2) indicate that 4-chloro-2-methylphenol is expected to adsorb very little to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(3) based upon a Henry's Law constant of 1.1X10-6 atm-cu m/mole(4). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 40 days and 290 days, respectively(SRC). According to a classification scheme(6), BCF values ranging from 6.4-28(5) and a regression-derived equation(7) suggest the potential for bioconcentration in aquatic organisms is low(SRC). Chlorinated phenols will undergo photolysis in aqueous solutions as a result of ultraviolet irradiation, and that photodegradation leads to the substitution of hydroxyl groups in place of the chlorine atoms with subsequent polymer formation(8). Degradation rates for 4-chloro-2-methylphenol were 2.8 ug/l/day at an initial concentration of 18 ug/l in a sea water shake flask die-away test and 0.04 ug/l/day at an initial concentration of 3.6 ug/l in a waste water shake flask die-away test(9). Mixed cultures of phenol adapted microorganisms exhibited moderate oxygen uptake as the test concentration of 4-chloro-2-methylphenol was reduced from 80 ppm to 50 ppm over a 3 hour period(10,11). An activated sludge pilot plant was operated at 4, 6, and 9 day sludge ages with the same influent settled sewage; higher concentrations of 4-chloro-2-methylphenol were seen in the effluent from the unit run at a 4 day sludge age(12). Based on these studies, 4-chloro-2-methylphenol is expected to biodegrade in the aquatic environment.

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 4-chloro-2-methylphenol, which has a vapor pressure of 2.40X10-2 mm Hg at 25 deg(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase 4-chloro-2-methylphenol 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 32 hours(SRC), calculated from its rate constant of 1.2X10-11 cu cm/molecule-sec at 25 °C that was derived using a structure estimation method(3). 4-Chloro-2-methylphenol may undergo direct photolysis due to the absorption of UV light wavelengths above 290 nm(4).

4-Chloro-2-methylphenol, a biodegradation product of 2-methyl-4-chlorophenoxyacetic acid (MCPA)(1), was detected upon potatoes, carrots, green salad and onions grown from fields adjacent to a treated railroad bed in Northern Finland at concn of 0.2, 2.9, 52.9, and 593.0 ppb, respectively, 2 wk post application of MCPA(2).

/AQUATIC SPECIES/ Trout were exposed to 4-chloro-o-cresol (a metabolite of MCPA) at concentrations of 0.5 or 1.0 ppm for 4 wks. Other fish were exposed to 0.5, 1.0 or 1.5 ppm concentrations for 3 wk periods. Histopathological changes brought about by these exposures were greatest in the gills and kidney. In the gills the changes were remarkable due to lamella telangiectasis in some filaments. It is noted that these changes were not evident in fish kept under 10 and 30 ppm MCPA technical grade solutions.

/AQUATIC SPECIES/ The acute toxicities of several chlorinated phenols, catechols, and cresols, including 4-chloro-o-cresol, to trout were determined. The cresols were lethal in concentrations of 1-2 ppm.

/OTHER TERRESTRIAL SPECIES/ The Frog Embryo Teratogenesis Assay-Xenopus (FETAX) has been applied mainly in pharmacology to examine the toxicity of drugs on embryos (mortality, malformation and growth inhibition). The original FETAX methodology has been modified by us using the in vitro fertilization (ivf) and has been applied to ecotoxicological studies. ...In this preliminary study, we have tested chlorocresol (4-chloro-o-cresol), a soil metabolite of the pesticide MCPA (4-chloro-2-methylphenoxy acetic acid). Embryos were exposed to the chlorocresol (40, 30 mg/l of control FETAX solution) during the cleavage phase. This treatment causes a lethality in concentration-dependent manner. Lethality, evaluated at the end of the test (5 days post fertilization), was due to an high frequency of severe malformed embryos not surviving during the test.

4-Chloro-2-methylphenol, a biodegradation product of 2-methyl-4-chlorophenoxyacetic acid (MCPA)(1), was detected upon branches sprayed with MCPA, 2 wk post application, at concn of 8900 ppb and upon potatoes, carrots, green salad and onions grown from fields adjacent to a treated railroad bed in Northern Finland at concn of 0.2, 2.9, 52.9, and 593.0 ppb, respectively(2).

Cough. Laboured breathing. Shortness of breath. Sore throat. Burning sensation.

Skin burns. Pain. Redness.

Pain. Redness. Severe deep burns.

Abdominal pain. Burning sensation. Shock or collapse. Sore throat.

4-Chloro-2-methylphenol was detected in the wastewater sludge, final effluent, and a soil column simulating sludge disposal upon agricultural lands at a concentration of 0.12 mg/kg of dry solids, less than 5 ng/l, and 217 ng/l, respectively(1). The average concentration of 4-chloro-2-methylphenol detected in sewage treatment effluents in England and Wales in 1995 was 3.1254 ug/l with a frequency of detection of 47.06 percent(2). The concentration of 4-chloro-2-methylphenol detected in leachate from contaminated groundwater below a landfill in Sorup, Denmark ranged from less than 0.001 ug/l to 0.019 ug/l with a mean concentration of 0.005 ug/l(3). 4-Chloro-2-methylphenol was identified in three leachate samples taken from a municipal landfill in Gryta, Vasteras, Sweden(4). This chemical was detected in agrochemical sewage at a concentration of 2400 ug/l and in secondary sewage effluent at a concentration of 4 ug/l(5).

The recommended criterion level for 2-methyl-4-chlorophenol is 1,800 ug/l.

Toxic pollutant designated pursuant to section 307(a)(1) of the Federal Water Pollution Control Act and is subject to effluent limitations. Chlorinated phenols (includes trichlorophenols and chlorinated cresols)/

2-Methyl-4-chlorophenol at high concentration decreased the respiration rate of isolated rat liver mitochondria by inhibiting the NAD-dependent dehydrogenases.

The physiological activities of 22 phenols (including 4-chloro-2-methylphenol) were related to various quantum chemical indexes of the compounds. The three factors that seemed to have the most significance for the activity of the phenols were the energy of the highest occupied molecular orbital and the reduced Mulliken overlap populations relative to the oxygen atom and the C-OH bonds.

Chlorinated phenols ...are very effective (...in vitro) as uncouplers of oxidative phosphorylation. They thus prevent incorporation of inorganic phosphate into ATP without affecting electron transport. As a result of this action, which is believed to occur at mitochondrial /srp: membrane/, cells continue to respire but soon are depleted of ATP necessary for growth. /Chlorophenols/

An enzyme preparation metabolizing phenoxyacetate herbicides was made from a soil arthrobacter species. Crude extracts degraded 2,4-D, 4-chloro-2-methylphenoxyacetic acid, and 2- and 4-chlorophenoxyacetates. The products formed from 2,4-D, 4-chloro-2-methylphenoxyacetic acid, and 2-, and 4-dichlorophenoxyacetates were identified as 2,4-dichlorophenol, 2-methyl-4-chlorophenol, and 2- and 4-chlorophenols. The bacterial extract was capable of metabolizing catechol and 3-methyl, 4-chloro-, and 3,5-dichlorocatechols.

A bacterium capable of degrading 4-chloro-2-methylphenoxyacetic acid (MCPA) was isolated from soil and identified as flavobacterium peregrinum. Extracts of cells of flavobacterium peregrinum and of a phenoxy-acetate-metabolizing arthrobacter species dehalogenated 4-chloro-2-methylphenoxyacetic acid and several catechols but not 4-chloro-2-methylanisole. An arthrobacter species cell extract was fractionated, and an enzyme preparation was obtained which catalyzed the conversion of 4-chloro-2-methylphenoxyacetic acid to 4-chloro-2-methylphenol. The latter compound was not metabolized unless NADH was added.

Samples (200 g) of a sandy clay soil were incubated with 4-chloro-2-methylphenoxyacetic acid (MCPA) for 0-32 wk at 23 °C. 4-chloro-2-methylphenol was identified as a degradation product of 4-chloro-2-methylphenoxyacetic acid.

The Gram-negative strain S1, isolated from activated sludge, metabolized 4-chloro-2-methylphenol by an inducible pathway via a modified ortho-cleavage route as indicated by a transiently secreted intermediate, identified as 2-methyl-4-carboxymethylenebut-2-en-4-olide by gas chromatography/mass spectrometry. Beside 4-chloro-2-methylphenol only 2,4-dichlorophenol and 4-chlorophenol were totally degraded, without an accumulation of intermediates. The chlorinated phenols tested induced activities of 2,4-dichlorophenol hydroxylase and catechol 1,2-dioxygenase type II. Phenol itself appeared to be degraded more efficiently via a separate, inducible ortho-cleavage pathway. The strain was characterized with respect to its physiological and chemotaxonomic properties. The fatty acid profile, the presence of spermidine as main polyamine, and of ubiquinone Q-10 allowed the allocation of the strain into the alpha-2 subclass of the Proteobacteria. Ochrobactrum anthropi was indicated by fatty acid analysis as the most similar organism, however, differences in a number of physiological features (e.g. absence of nitrate reduction) and pattern of soluble proteins distinguished strain S1 from this species.

Used to make herbicides (Mecoprop, MCPA, and MCPB), as an additive tracer for resist plasma etching, and as a disinfectant; [HSDB] Metabolite of 2-methyl-4-chlorophenoxyacetic acid & other phenoxyacetic acid herbicides. [ChemIDplus] Used as a closed system intermediate in phenoxy herbicide production; [IUCLID]

Semiconductor Manufacturing [Category: Industry]

CHEM INTERMEDIATE, EG, FOR MECOPROP, MCPA & MCPB HERBICIDES; CHEM INTERMEDIATE FOR ITS SODIUM SALT.

Feedstock for the synthesis of pesticides; Additive tracer for resist plasma etching. Disinfectant. Manufacture of the herbicide 4-chloro-2-methylphenoxyacetic acid (MCPA). Exhibits fungicidal activity.

For chloro-ortho-cresol (USEPA/OPP Pesticide Code: 062190) there are 0 labels match. /SRP: Not registered for current 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./

(1979) 6.26X10+8 G (PRINCIPAL CUSTOMS DISTRICT)

(1981) 1.78X10+8 G (PRINCIPAL CUSTOMS DISTRICT)

Phenol, 4-chloro-2-methyl-: ACTIVE

PHOTOLYSIS OF DILUTE AQUEOUS 4-CHLORO-2-METHYLPHENOXYACETIC ACID (MCPA) SOLUTIONS WITH EITHER SUNLIGHT OR AN INDOOR PHOTOREACTOR YIELDED 4-CHLORO-2-METHYLPHENOL AS THE MAJOR PRODUCT.