3,4-Dichlorophenol

less than 1 mg/mL at 68 °F (NTP, 1992)

Very soluble in ethanol, ethyl ether; soluble in benzene, petroleum ether

In water, 9,260 mg/L at 25 °C

488.3 °F at 767 mmHg (NTP, 1992)

253 °C

151 to 154 °F (NTP, 1992)

68 °C

3,4-dichlorophenol appears as needles (from benzene, petroleum ether) or light brown and yellow crystals. Odor threshold 100 micrograms/liter. Taste threshold 0.3 micrograms/liter in water. (NTP, 1992)

Solid; [HSDB] Yellow solid; [MSDSonline]

This chemical does not meet GHS hazard criteria for 1.8% (1 of 56) of reports.

Danger

H302 (89.3%): Harmful if swallowed [Warning Acute toxicity, oral]

P261, P264, P264+P265, P270, P271, P273, P280, P301+P317, P302+P352, P304+P340, P305+P351+P338, P305+P354+P338, P317, P319, P321, P330, P332+P317, P337+P317, P362+P364, P391, P403+P233, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 56 reports by companies from 10 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Warning

T - indicates a substance that is the subject of a final TSCA section 4 test rule.

3,4-Dichlorophenol: Does not have an individual approval but may be used under an appropriate group standard

SYMPTOMS: Symptoms of exposure to this compound may include irritation of the skin, eyes, mucous membranes and upper respiratory tract. Prolonged contact can cause damage to the eyes, severe irritation and burns. Exposure to this class of compounds may cause profuse sweating, intense thirst, abdominal pain, nausea, vomiting, diarrhea, cyanosis from methemoglobinemia, hyperactivity, stupor, blood pressure fall, hyperpnea, hemolysis, convulsions, collapse, coma and pulmonary edema followed by pneumonia. If death from respiratory failure is not immediate, jaundice and oliguria or anuria may occur. Other symptoms of exposure to this class of compounds may include headache, dizziness, rapid and difficult breathing, weakness, severe burns and internal damage. Chronic exposure may result in digestive disturbances, nervous disorders, skin eruptions and liver and kidney damage. Skin contact with this type of compound may result in softening and whitening of the skin, followed by the development of painful burns. Prolonged contact may lead to dermatitis. Local contact may also result in painless blanching or erythema and corrosion of the skin. Skin sensitivity reactions occur occasionally.

Adverse effects may include skin burns, methemoglobinemia, liver injury, kidney injury, and convulsions; [CAMEO] An irritant; Effects in high-dose animal studies include convulsions; [MSDSonline] See CHLOROPHENOLS.

The major hazards encountered in the use and handling of 3,4-dichlorophenol stem from its toxicologic properties. Exposure to this crystalline substance may occur from dermal contact or inhalation at sites where it is used as a chemical intermediate. Effects from exposure include burning of the skin, headache, dizziness, cyanosis, and death from cardiac or respiratory failure. Personnel handling 3,4-dichlorophenol should wear protective clothing, gloves, boots, goggles, and an approved dust respirator. In emergency situations, wear a self-contained breathing apparatus and structural firefighter's protective clothing. Remove and isolate contaminated clothing at the site. In case of contact with 3,4-dichlorophenol, immediately flush skin or eyes with running water for at least 15 minutes, and wash affected areas of the skin with soap and water. 3,4-Dichlorophenol does not ignite easily, but it can burn, producing irritating and poisonous gases. For small fires involving 3,4-dichlorophenol, extinguish with dry chemical, CO2, water spray, or standard foam, and for large fires, use water spray, fog, or standard foam. Dike runoff from fire control water if necessary to keep it from entering water sources or sewers where it may cause pollution. 3,4-Dichlorophenol may be shipped via air, rail, road, or water in containers bearing the label, "Keep away from food." Small spills of 3,4-dichlorophenol solution may be taken up with sand or other noncombustible absorbent and placed into containers for later disposal. Large spills should be contained in pits, or other holding areas that are sealed with an impermeable flexible membrane liner. Solids should be covered with a plastic sheet. Spills of 3,4-dichlorophenol in water may be trapped at the bottom with sand bag barriers, activated charcoal applied, and trapped material removed with suction hoses, mechanical dredges, or lifts. Prior to implementing land disposal of waste residue (including waste sludge), consult with environmental regulatory agencies for guidance.

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

KOZAK VP ET AL; REVIEWS OF THE ENVIRONMENTAL EFFECTS OF POLLUTANTS: XI. CHLOROPHENOLS; US EPA REP EPA-600/1-79-012: 519 PAGES (1979). THIS PAPER DISCUSSES THE HEALTH & ENVIRONMENTAL EFFECTS, PHYSICAL & CHEMICAL PROPERTIES, ANALYTICAL METHODS, BIOLOGICAL ASPECTS (HUMAN & NON-HUMAN), ENVIRONMENTAL DISTRIBUTION & TRANSFORMATION & ENVIRONMENTAL INTERACTIONS OF CHLOROPHENOLS & THEIR CONSEQUENCES. AVAILABLE DATA INDICATE THAT CHLOROPHENOLS DO NOT POSSESS TUMORIGENIC, MUTAGENIC OR TERATOGENIC PROPERTIES.

Environmental Protection Service. Chlorophenols and Their Impurities in the Canandian Environment Report EPS 3-EC-81-2 (1981).

Environment Canada; Tech Info for Problem Spills: Phenol (Draft) (1981).

/GUIDE 153: SUBSTANCES - TOXIC AND/OR CORROSIVE (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. /Chlorophenols, liquid; Chlorophenols, solid/

/GUIDE 153: SUBSTANCES - TOXIC AND/OR CORROSIVE (COMBUSTIBLE)/ Fire or Explosion: Combustible material: may burn but does not ignite readily. When heated, vapors may form explosive mixtures with air: indoors, outdoors, and sewers explosion hazards. Those substances designated with a "P" may polymerize explosively when heated or involved in a fire. Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated. Runoff may pollute waterways. Substance may be transported in a molten form. /Chlorophenols, liquid; Chlorophenols, solid/

/GUIDE 153: SUBSTANCES - TOXIC AND/OR CORROSIVE (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. /Chlorophenols, liquid; Chlorophenols, solid/

/GUIDE 153: SUBSTANCES - TOXIC AND/OR CORROSIVE (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. /Chlorophenols, liquid; Chlorophenols, solid/

For more DOT Emergency Guidelines (Complete) data for 3,4-DICHLOROPHENOL (8 total), please visit the HSDB record page.

Acute Tox. 4 (89.3%)

Acute toxicity (Oral) - Category 4

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.

Land Spill: Dig a pit, pond, lagoon, or holding area /SRP: If time permits, pits, ponds, lagoons, soak holes, or holding areas should be sealed with an impermeable flexible membrane liner./ to contain liquid or solid material. Cover solids with plastic sheet to prevent dissolving in rain or fire fighting water. /Trichlorophenol/

Water Spill: Use natural deep water pockets, excavated lagoons, or sand bag barriers to trap material at bottom. If dissolved, apply activated carbon at ten times the spilled amount in region of 10 ppm or greater concentration. Remove trapped material with suction hoses. Use mechanical dredges or lifts to remove immobilized masses of pollutants and precipitates. /Trichlorophenol/

ACTIVATED CARBON IS A GOOD METHOD FOR REMOVING CHLOROPHENOLS FROM WATER. COMPETITIVE ADSORPTION OCCURS BETWEEN CHLOROPHENOLS & HUMIC SUBSTANCES PRESENT IN NEARLY ALL MUNICIPAL WATER SUPPLIES. THIS COMPETITION DECR 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: 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.

Keep material out of water sources and sewers; Build dikes to contain flow as necessary; Keep upwind; Avoid breathing vapors or dusts; Wash away any material which may have contacted the body with copious amounts of water or soap and water. /Trichlorophenol/

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.

Immediately wash contaminated areas of skin with concentrated soap solution. Contaminated gloves, clothing, shoes should be removed without delay and disposed by incineration.

SRP: Contaminated protective clothing should be segregated in such a manner so that there is no direct personal contact by personnel who handle, dispose, or clean the clothing. Quality assurance to ascertain the completeness of the cleaning procedures should be implemented before the decontaminated protective clothing is returned for reuse by the workers. Contaminated clothing should not be taken home at end of shift, but should remain at employee's place of work for cleaning.

SRP: Wastewater from contaminant suppression, cleaning of protective clothing/equipment, or contaminated sites should be contained and evaluated for subject chemical or decomposition product concentrations. Concentrations shall be lower than applicable environmental discharge or disposal criteria. Alternatively, pretreatment and/or discharge to a POTW is acceptable only after review by the governing authority. Due consideration shall be given to remediation worker exposure (inhalation, dermal and ingestion) as well as fate during treatment, transfer and disposal. If it is not practicable to manage the chemical in this fashion, it must meet Hazardous Material Criteria for disposal.

MINIMUM PROTECTIVE CLOTHING: If Tyvek-type disposable protective clothing is not worn during handling of this chemical, wear disposable Tyvek-type sleeves taped to your gloves.

Wear boots, protective gloves, and goggles. /Trichlorophenol/

/Wear/ approved dust respirator for toxic dusts; Protective clothing to prevent contact with skin. /Trichlorophenol/

3,4-Dichlorophenol was detected in 8 of 10 urine samples collected from adults at concentrations ranging from 12 to 96 ppb, with an average concentration of 47 ppb(1). 3,4-Dichlorophenol was detected in 12 of 197 urine samples collected from children residing in Arkansas at a maximum concentration of 9 ppb(2).

EC50; Species: Pseudokirchneriella subcapitata (Green algae); Conditions: freshwater, static; Concentration: 3200 ug/L for 96 hr; Effect: growth, general

LC50; Species: Pseudokirchneriella subcapitata (Green algae); Conditions: freshwater, static; Concentration: 1900 ug/L for 96 hr (95% confidence interval: 830-2800 ug/L)

LC50; Species: Platichthys flesus (European flounder, weight 56 g); Conditions: saltwater, renewal, 6 °C, pH 8, salinity 5 ppt; Concentration: 2300 ug/L for 96 hr /98-99% purity/

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 860(SRC), determined from a log Kow of 3.33(2) and a regression-derived equation(3), indicates that 3,4-dichlorophenol is expected to have low mobility in soil(SRC). The pKa of 3,4-dichlorophenol is 8.63(4), indicating that this compound will partially exist in the anion form and anions generally do not adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts(5). Volatilization of 3,4-dichlorophenol from moist soil surfaces is expected to be an important fate process(SRC) given an estimated Henry's Law constant of 4.77X10-7 atm-cu m/mole(SRC), using a fragment constant estimation method(6). 3,4-Dichlorophenol is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 0.00371 mm Hg(SRC), determined from a fragment constant method(7). 3,4-Dichlorophenol exhibits far ranging biodegradation rates in soil from, from half-lives of 18 days an acidic sandy loam, 3 days in basic sandy silt loam(8), and 160 days in a clay loam soil(9), suggesting that biodegradation in soil is probably affected by many factors(SRC).

TERRESTRIAL FATE: Contamination of soil in the vicinity of two Finnish sawmills using preservative (Ky-5) against blue staining fungi that contained chlorophenols was studied. The soil around the treatment basins contained up to 70 mg chlorophenols/kg and that in the storage area for treated lumber up to 6 mg/kg. Contamination extended to a depth of at least 2 m near the treatment basins. Surface water inside the sawmill area contained the same chlorophenols as those used in wood preservation, plus some additional isomers. The ground water and lake water around the sawmill areas were contaminated. The fate of different chlorophenols in soil is probably affected by many factors, such as the water solubility of each chlorophenol, pH of the soil, rainfall, soil organic matter content, type and particle size of the soil, biological and photodegradation and the evaporation of each chlorophenol(1).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 860(SRC), determined from a log Kow of 3.33(2) and a regression-derived equation(3), indicates that 3,4-dichlorphenol is expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(3) based upon an estimated Henry's Law constant of 4.77X10-7 atm-cu m/mole(SRC), developed using a fragment constant estimation method(4). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 98 days and 720 days, respectively(SRC). According to a classification scheme(5), a measured BCF range of 22-84(6), and a regression-derived equation(7), suggests the potential for bioconcentration in aquatic organisms is moderate. A 0% of theoretical BOD using activated sludge in the Japanese MITI test(6) suggests 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), 3,4-dichlorophenol, which has an estimated vapor pressure of 0.00371 mm Hg at 25 °C(SRC), determined from a fragment constant method(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase 3,4-dichlorophenol 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 about 2 days(SRC), calculated from its estimated rate constant of 6.99X10-12 cu cm/molecule-sec at 25 °C that was derived using a structure estimation method(3). 3,4-Dichlorophenol contains chromophores that absorb at wavelengths >290 nm(4) and therefore may be susceptible to direct photolysis by sunlight(SRC).

PENTACHLOROPHENOL, DECOMP WITHIN FEW WK AFTER ITS APPLICATION IN RICE FIELDS. ONE STABLE DECOMP PRODUCT FOUND IN PADDY SOIL WAS 3,4-DICHLOROPHENOL.

The following link will take the user to the National Toxicology Program (NTP) Test Agent Search Results page, which tabulates all of the "Standard Toxicology & Carcinogenesis Studies", "Developmental Studies", and "Genetic Toxicity Studies" performed with this chemical. Clicking on the "Testing Status" link will take the user to the status (i.e., in review, in progress, in preparation, on test, completed, etc.) and results of all the studies that the NTP has done on this chemical.[http://ntp-apps.niehs.nih.gov/ntp_tox/index.cfm?fuseaction=ntpsearch.searchresults&searchterm=95-77-2]

Biologically treated effluent samples from nine Canadian bleached softwood Kraft mills were analyzed for chlorinated phenolic content. Chlorinated phenolics present in effluent discharged from bleached Kraft mills are not expected to contribute an off-odor to recipient waters. /Chlorinated phenols/

3,4-Dichlorophenol was detected in 0 of 34 treated water samples collected at a sewage treatment plant in Karkola, Finland between September 1989 and November 1990(1). 3,4-Dichlorophenol was detected in one sample of aqueous leachate collected at a hazardous waste site in Germany at a concentration of 10.9 ppm(2). 3,4-Dichlorophenol was detected in 4 of 4 samples of incinerator ash collected in Missouri between February 1985 and April 1985 at an average concentration of 100 ppm(3); the ash was generated from the incineration of soil contaminated with organo-halogen compounds. 3,4-Dichlorophenol was detected in 2 of 5 samples of gas emissions from a metal reclamation plant in Finland, at an average concentration of 0.1 ug/cu Nm(4).

The Koc of 3,4-dichlorophenol is estimated as 860(SRC), using a log Kow of 3.33(1), and a regression-derived equation(2). According to a classification scheme(3), this estimated Koc value suggests that 3,4-dichlorophenol is expected to have low mobility in soil. The pKa of 3,4-dichlorophenol is 8.63(4), indicating that this compound will partially exist in anion form in the environment and anions generally do not adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts(5).

Dichlorophenols can be synthesized directly by soil fungi utilizing chloride ions and humic phenols found in soil(1); chloroperoxidase enzymes released into soil by fungi can also bring about the chlorination of humic phenols with chloride ions(1). Chlorophenols may be released into the environment through burning of fresh lignocellulosic biomass during forest fires(2). /Dichlorophenols/

URBAN/SUBURBAN: 3,4-Dichlorophenol was detected in 6 of 6 air samples collected in Green Bay, Wisconsin in June 1989 at an average concentration of 0.18 ng/cu m(1). 3,4-Dichlorophenol was detected in 11 of 11 air samples collected in Georgetown, South Carolina from January 1989 to May 1991 at an average concentration of 0.019 ng/cu m(1).

RURAL/REMOTE: 3,4-Dichlorophenol was detected in 6 of 6 air samples collected in North Inlet, South Carolina from January 1989 to May 1991 at an average concentration of 0.014 ng/cu m(1).

/SIGNS AND SYMPTOMS/ SYMPTOMATOLOGY: Burning pain in mouth and throat. White necrotic lesions in mouth, esophagus and stomach. Abdominal pain, vomiting ... and bloody diarrhea. Pallor, sweating, weakness, headache, dizziness, tinnitus. Shock: Weak irregular pulse, hypotension, shallow respirations, cyanosis, pallor, and a profound fall in body temperature. Possibly fleeting excitement and confusion, followed by unconsciousness. ... Stentorous breathing, mucous rales, rhonchi, frothing at nose and mouth and other signs of pulmonary edema are sometimes seen. Characteristic odor of phenol on the breath. Scanty, dark-colored ... urine ... moderately severe renal insufficiency may appear. Methemoglobinemia, Heinz body hemolytic anemia and hyperbilirubinemia have been reported. ... Death from respiratory, circulatory or cardiac failure. 9. If spilled on skin, pain is followed promptly by numbness. The skin becomes blanched, and a dry opaque eschar forms over the burn. When the eschar sloughs off, a brown stain remains. /Phenol/

/EPIDEMIOLOGY STUDIES/ Several epidemiological studies have been published concerning human cancer outcomes following occupational exposure to chlorophenols, phenoxy herbicides (made from or contaminated with chlorophenols) and chlorinated dibenzo-p-dioxins and dibenzofurans (microcontaminants found in some chlorophenols and phenoxy herbicides). Most of these studies (case-control and cohort studies) have been described and reviewed in several publications by IARC (1979, 1986, 1987). Equivocal relationships between chlorophenols and cases of soft tissue sarcoma, malignant lymphoma (Hodgkins disease and non-Hodgkins lymphoma), nasal and nasopharyngeal cancer and lung cancer have been reported. IARC concluded that there is a limited evidence of carcinogenicity from occupational exposure to chlorophenols ... /Chlorophenols/

/ALTERNATIVE and IN VITRO TESTS/ Nineteen isomeric chlorophenols were tested for their toxicity to HeLa cells. Cytotoxicity (median inhibitory concn IC50) varied between 0.37 and 900 mg/L and generally increased in proportion to the number of chlorine substituents and the partition coefficient. Ortho chlorination decreased toxicity, whereas meta chlorination had the opposite effect. A good correlation was found between HeLa cell toxicity and data on the bacterial toxicity of the substances.

/OTHER TOXICITY INFORMATION/ The toxicity of chlorophenols tends to increase as chlorination is increased. /Chlorophenols/

3,4-Dichlorophenol formation from the chlorination processes involving water treatment(1), various incineration processes(2), and during wood pulp bleaching(2) will result in its direct release to the environment(SRC). The origin of chlorophenols during wood pulp bleaching is via chlorination of naturally occuring lignins found in wood(3). 3,4-Dichlorophenol may be released to the environment via biodegradation in soil of 1,2,3-trichlorbenzene(4), and via biodegradation in sediment of both 2,3,4,5-tetrachlorophenol and pentachlorophenol(5).

AEROBIC: 3,4-Dichlorophenol, present at 100 mg/L, reached 0% of its theoretical BOD in 4 weeks using an activated sludge inoculum at 30 mg/L in the Japanese MITI test(1). 3,4-Dichlorophenol, present at 22 ppm in Wiggins, Mississippi acidic sandy loam with a pH of 4.8, reached ca. 90% transformation to unspecified intermediates in 54 days, with a half-life of 18 days(2); 3,4-dichlorophenol, present at 30 ppm in Austin, Texas basic sandy silt loam with a pH of 7.8, reached 90% transformation to unspecified intermediates in ca. 9 days, with a half-life of 3 days(2). 3,4-Dichlorophenol, present at 119 ppm in Waterloo, Ontario, Canada clay loam soil with a pH of 7.1, reached 88% transformation to unspecified intermediates in 160 days(3).

ANAEROBIC: 3,4-Dichlorophenol, present at 9 ppm (55 uM) in water, reached 82% transformation to 3-chlorophenol in 21 days, employing a mixed inoculum obtained from sewage sludge(1). 3,4-Dichlorophenol, present at 50-80 ppm in water collected from a groundwater aquifer bordering a municipal landfill in Norman, Oklahoma, reached 12% transformation to unidentified products after 12 weeks(2). 3,4-Dichlorophenol, present at 10 ppm in water, reached 100% transformation to 4-chlorophenol in 30 days, employing a mixed inoculum obtained from sewage sludge(3). 3,4-Dichlorophenol, present at 0.51-1.1 ppm in Lake Kasumigaura, Japan sediment, reached 100% transformation to 3-chlorophenol, 4-chlorophenol and phenol over one year, with a half-life of 41 days(4); the mechanism of transformation was via reductive dechlorination in which chlorine on the phenolic ring is replaced with hydrogen. 3,4-Dichlorophenol, present at 0.65 ppm in Tsurumi River, Tokyo Bay, Japan estuarine sediment, reached ca 65% transformation to 3-chlorophenol and 4-chlorophenol over 120 days, with a half-life of 70 days(5); the mechanism of transformation was via microorganism-mediated reductive dechlorination. 3,4-Dichlorophenol, present at 14 ppm in freshwater pond sediment, reached 10% transformation to unknown intermediates over 12 weeks(6).

THE BIODEGRADATION OF RADIOCHEMICALLY PURE (99%) 1,2,3-TRICHLOROBENZENE IN SOIL WAS INVESTIGATED; 3,4-DICHLOROPHENOL WAS PRESENT IN SOILS INCUBATED WITH 1,2,3-TRICHLOROBENZENE.

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, cells continue to respire but soon are depleted of ATP necessary for growth. /Chlorophenols/

The aim of this study is to investigate the chemical retinoic acid (RA) disruption at the level of retinoid X receptor (RXR) functioning. This assay makes use of recombined human RXR gene and reporter gene yeast, which specifically expresses beta-galactosidase when incubated with exogenous 9-cis retinoic acid (9-cis RA). Agonistic and antagonistic actions of chemicals including a series of phenols, phthalates, organochlorine pesticides (OCPs) were tested in the absence and presence of 5 x 10-6 mol/L 9-cis RA, at which maximal beta-galactosidase activity could be induced. The results obtained reveal that some chemicals, e.g., 2-t-butylphenol, 2-isopropylphenol, 2,4-dichlorophenol (2,4-DCP), 3,4-dichlorophenol (3,4-DCP), 4-tert-octylphenol (4-t-OP) and hexachlorobenzene (HCB), are RXR agonists...

... To investigate the relation between metabolism and toxicity of 1,2-dichlorobenzene (1,2-DCB), the biotransformation, tissue distribution, blood kinetics, and excretion at three different oral dose levels (5, 50 and 250 mg/kg) of the radiolabelled compound were investigated in the male Wistar rat. A toxic dose level (250 mg/kg...) was included. ... The concentration of parent chemical was essentially constant during 3 and 6 hr for the mid- and high-dose level respectively, and then declined. 1,2-DCB could only be detected in blood in the first 2 hr after administration of the 5-mg/kg dose. The major route of biotransformation was via the glutathione pathway and 60% of the urinary metabolites were mercapturic acids. In addition, the major metabolites in bile were conjugates of glutathione. Other major metabolites in urine were the sulfate conjugates of 2,3- and 3,4-dichlorophenol (DCP). No significant differences in metabolic profiles were observed between the different doses. Induction with phenobarbital resulted in the increased excretion of sulfate conjugates (30% in the induced rat, 20% in the control rat), mainly the conjugate of 3,4-DCP...

Yields 3,4-dichlorocatechol in rabbit; yields 4,5-dichlorocatechol, 3,4-dichlorophenyl-beta-d-glucuronide, & 3,4-dichlorophenyl sulfate in rabbit... /From table/

1,2-Dichlorobenzene gave 3,4-dichlorophenol with smaller amounts of 2,3-dichlorophenol, 3,4- and 4,5-dichlorocatechol and 3,4-dichlorophenylmercapturic acid also observed; 1,3-dichlorobenzene gave 2,4-dichlorophenol as the major product with 3,5-dichlorophenol, 3,4-dichlorocatechol, and 2,4-dichlorophenylmercapturic acid also identified; 1,4-dichlorobenzene gave 2,5-dichlorophenol as the major metabolite with 2,5-dichlorquinol identified as a minor product.

3,4-dichlorophenol is a known human metabolite of 1,2-dichlorobenzene.

Because of their high lipid solubility and low ionization at physiological pH, dichlorophenols would be expected to be readily absorbed following ingestion. /Dichlorophenols/

Dichlorophenol isomers are absorbed through the skin and from the gut. /Dichlorophenol isomers/

... Readily absorbed from the gastroenteric tract and from parenteral sites of injection. /Chlorophenols/

Used as a chemical intermediate for 2-Chloro-1,4-dihydroxyanthraquinone and 2,3,4-Trichlorophenol; [HSDB]

CHEM INT FOR 2-CHLORO-1,4-DIHYDROXYANTHRAQUINONE & 2,3,4-TRICHLOROPHENOL

Hydrolysis of chlorobenzenes can be carried out in alkaline aqueous media, with or without the presence of copper salts. It can be done in the vapor phase at 250 - 400 °C on phosphates or on silica at 500 - 550 °C. Hydrolysis is most frequently carried out in the presence of methanolic sodium or potassium at 150 - 200 °C and 1.0 - 3.0 MPa. /Mono-, Di-, and Trichlorophenols with Chlorine in a Meta Position/

Sulfonation of chlorobenzenes followed by the desulfonation of chlorobenzenesulfonic acids can be used to produce numerous chlorophenols. The chlorobenzenes are sulfonated by using 15 - 20% oleum at 60 - 80 °C. The subsequent desulfonation is usually carried out by using 15 - 25% aqueous sodium hydroxide solution at 180 - 220 °C and 1.5 - 3.0 MPa. /Mono-, Di-, and Trichlorophenols with Chlorine in a Meta Position/

Sandmeyer Reaction. m-Chlorophenols can also be made by diazotization of the corresponding chloroanilines that have been obtained either by nitration of chlorobenzenes followed by hydrogenation or by chlorination of nitrobenzenes. /m-Chlorophenols/

Hydrodechlorination of polychlorophenols produces 3-chlorophenols. This reaction has long been carried out either in the vapor phase at 300 - 350 °C on an alumina catalyst or in the liquid phase at 150 - 250 °C and 15.0 - 20.0 MPa, usually in the presence of sulfur. /Mono-, Di-, and Trichlorophenols with Chlorine in a Meta Position/