4-Methoxyphenol

H302: Harmful if swallowed [Warning Acute toxicity, oral]

H317: May cause an allergic skin reaction [Warning Sensitization, Skin]

H319: Causes serious eye irritation [Warning Serious eye damage/eye irritation]

P261, P264, P264+P265, P270, P272, P280, P301+P317, P302+P352, P305+P351+P338, P321, P330, P333+P317, P337+P317, P362+P364, and P501 (click each P-code to see the statement)

This chemical does not meet GHS hazard criteria for 0.2% (11 of 4411) of reports.

H302 (99.8%): Harmful if swallowed [Warning Acute toxicity, oral]

H317 (99.7%): May cause an allergic skin reaction [Warning Sensitization, Skin]

H319 (99.7%): Causes serious eye irritation [Warning Serious eye damage/eye irritation]

H412 (12.9%): Harmful to aquatic life with long lasting effects [Hazardous to the aquatic environment, long-term hazard]

P261, P264, P264+P265, P270, P272, P273, P280, P301+P317, P302+P352, P305+P351+P338, P321, P330, P333+P317, P337+P317, P362+P364, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 4411 reports by companies from 22 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Reported as not meeting GHS hazard criteria per 11 of 4411 reports by companies.

There are 21 notifications provided by 4400 of 4411 reports by companies with hazard statement code(s).

Information may vary between notifications depending on impurities, additives, and other factors. The percentage value in parenthesis indicates the notified classification ratio from companies that provide hazard codes. Only hazard codes with percentage values above 10% are shown. For more detailed information, please visit ECHA C&L website.

H320: Causes eye irritation [Warning Serious eye damage/eye irritation]

H351: Suspected of causing cancer [Warning Carcinogenicity]

H361: Suspected of damaging fertility or the unborn child [Warning Reproductive toxicity]

H401: Toxic to aquatic life [Hazardous to the aquatic environment, acute hazard]

P203, P261, P264, P264+P265, P270, P272, P273, P280, P301+P317, P302+P352, P305+P351+P338, P318, P321, P330, P333+P317, P337+P317, P362+P364, P405, and P501 (click each P-code to see the statement)

H315: Causes skin irritation [Warning Skin corrosion/irritation]

P264, P264+P265, P270, P280, P301+P317, P302+P352, P305+P351+P338, P321, P330, P332+P317, P337+P317, P362+P364, and P501 (click each P-code to see the statement)

H402: Harmful to aquatic life [Hazardous to the aquatic environment, acute hazard]

H412: Harmful to aquatic life with long lasting effects [Hazardous to the aquatic environment, long-term hazard]

P264, P264+P265, P270, P273, P280, P301+P317, P305+P351+P338, P330, P337+P317, and P501 (click each P-code to see the statement)

Fresh air, rest.

Remove contaminated clothes. Rinse and then wash skin with water and soap.

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. 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.

SKIN: IMMEDIATELY flood affected skin with water while removing and isolating all contaminated clothing. Gently wash all affected skin areas thoroughly with soap and water. If symptoms such as redness or irritation develop, IMMEDIATELY call a physician and be prepared to transport the victim to a hospital for treatment.

INHALATION: IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. If symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop, call a physician and be prepared to transport the victim to a hospital. Provide proper respiratory protection to rescuers entering an unknown atmosphere. Whenever possible, Self-Contained Breathing Apparatus (SCBA) should be used; if not available, use a level of protection greater than or equal to that advised under Protective Clothing.

INGESTION: DO NOT INDUCE VOMITING. If the victim is conscious and not convulsing, give 1 or 2 glasses of water to dilute the chemical and IMMEDIATELY call a hospital or poison control center. Be prepared to transport the victim to a hospital if advised by a physician. If the victim is convulsing or unconscious, do not give anything by mouth, ensure that the victim's airway is open and lay the victim on his/her side with the head lower than the body. DO NOT INDUCE VOMITING. IMMEDIATELY transport the victim to a hospital. (NTP, 1992)

(General first aid procedures)

Eye: Irrigate immediately - If this chemical contacts the eyes, immediately wash (irrigate) the eyes with large amounts of water, occasionally lifting the lower and upper lids. Get medical attention immediately.

Skin: Soap flush immediately - If this chemical contacts the skin, immediately flush the contaminated skin with soap and water. If this chemical penetrates the clothing, immediately remove the clothing and flush the skin with water. If irritation persists after washing, get medical attention.

Breathing: Respiratory support

Swallow: Medical attention immediately - If this chemical has been swallowed, get medical attention immediately.

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]:

CAUTION: Fire involving Safety devices (UN3268) and Fire suppressant dispersing devices (UN3559) may have a delayed activation and a risk of hazardous projectiles. Extinguish the fire at a safe distance.

SMALL FIRE: Dry chemical, CO2, water spray or regular foam.

LARGE FIRE: Water spray, fog or regular foam. Do not scatter spilled material with high-pressure water streams. If it can be done safely, move undamaged containers away from the area around the fire. Dike runoff from fire control for later disposal.

FIRE INVOLVING TANKS: Cool containers with flooding quantities of water until well after fire is out. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks in direct contact with flames. (ERG, 2024)

Use water spray, powder, alcohol-resistant foam, carbon dioxide.

Suitable extinguishing media: Use water spray, alcohol-resistant foam, dry chemical or carbon dioxide.

Advice for fire fighters: Wear self contained breathing apparatus for fire fighting if necessary.

Water or foam may cause frothing.

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]:

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.

SPILL: Increase the immediate precautionary measure distance, in the downwind direction, as necessary.

FIRE: If tank, rail tank car or highway tank is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2024)

Personal protection: particulate filter respirator adapted to the airborne concentration of the substance. Sweep spilled substance into covered sealable containers. Carefully collect remainder. Then store and dispose of according to local regulations.

Personal precautions, protective equipment and emergency procedures: Use personal protective equipment. Avoid dust formation. Avoid breathing vapors, mist or gas. Ensure adequate ventilation. Avoid breathing dust.

Enviornomental precautions: Prevent further leakage or spillage if safe to do so. Do not let product enter drains. Discharge into the environment must be avoided.

Methods and materials for containment and cleaning up: Pick up and arrange disposal without creating dust. Sweep up and shovel. keep in suitable, closed containers for disposal.

SRP: 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 air, soil or water; effects on animal, aquatic and plant life; and conformance with environmental and public health regulations. If it is possible or reasonable use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination.

SRP: The scientific literature for the use of contact lenses by industrial workers is inconsistent. The benefits 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.

The worker should immediately wash the skin when it becomes contaminated.

Work clothing that becomes wet or significantly contaminated should be removed and replaced.

Precautions for safe handling: Avoid contact with skin and eyes. Avoid formation of dust and aerosols. Provide appropriate exhaust ventilation at places where dust is formed.

For more Preventive Measures (Complete) data for 4-METHOXYPHENOL (6 total), please visit the HSDB record page.

SMALL SPILLS AND LEAKAGE: Should a spill occur while you are handling this chemical, you should dampen the solid spill material with alcohol, then transfer the dampened material to a suitable container. Use absorbent paper dampened with alcohol 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 alcohol followed by washing with a strong soap and water solution. Do not reenter the contaminate area until the Safety Officer (or other responsible person) has verified that the area has been properly cleaned.

STORAGE PRECAUTIONS: You should store this material in a refrigerator. (NTP, 1992)

Separated from strong oxidants, strong bases, acid anhydrides and acid chlorides.

Conditions for safe storage, including any incompatibilities: Keep container tightly closed in a dry and well-ventilated place.

... Commercially available mequinol and tretinoin topical solution should be protected from light and stored at room temperature, preferably in the manufacturer's carton. /Solage/

Store at 25 °C (77 °F): excursions permitted to 15-30 °C (59-86 °F).

10 [mg/m3]

53 [mg/m3]

320 [mg/m3]

TWA 5 mg/m3

none See Appendix G

See: IDLH INDEX

5.0 [mg/m3]

8 hr Time Weighted Avg (TWA): 5 mg/cu m.

Excursion Limit Recommendation: Excursions in worker exposure levels may exceed three times the TLV-TWA for no more than a total of 30 min during a work day, and under no circumstances should they exceed five times the TLV-TWA, provided that the TLV-TWA is not exceeded.

5 mg/m³ [1992]

DOE Protective Action Criteria (PAC): Temporary Emergency Exposure Limits (TEELs) for p-Methoxyphenol: TEEL-0: 5 mg/cu m; PAC-1: 15 mg/cu m; PAC-2: 100 mg/cu m; PAC-3: 500 mg/cu m (TEEL-0: The threshold concentration below which most people will experience no adverse health effects; PAC-1: The maximum concentration in air below which it is believed nearly all individuals could be exposed for up to one hour without experiencing other than mild transient adverse health effects or perceiving a clearly defined objectionable odor; PAC-2: The maximum concentration in air below which it is believed nearly all individuals could be exposed for up to one hour without experiencing or developing irreversible or other serious health effects or symptoms that could impair their abilities to take protective action; PAC-3: The maximum concentration in air below which it is believed nearly all individuals could be exposed for up to one hour without experiencing or developing life-threatening health effects).

A harmful contamination of the air will not or will only very slowly be reached on evaporation of this substance at 20 °C.

The substance is irritating to the eyes and skin.

Repeated or prolonged contact may cause skin sensitization. The substance may have effects on the skin. This may result in depigmentation.

Excerpt from NIOSH Pocket Guide for 4-Methoxyphenol:

Skin: PREVENT SKIN CONTACT - Wear appropriate personal protective clothing to prevent skin contact.

Eyes: PREVENT EYE CONTACT - Wear appropriate eye protection to prevent eye contact.

Wash skin: WHEN CONTAMINATED - The worker should immediately wash the skin when it becomes contaminated.

Remove: WHEN WET OR CONTAMINATED - Work clothing that becomes wet or significantly contaminated should be removed and replaced.

Change: DAILY - Workers whose clothing may have become contaminated should change into uncontaminated clothing before leaving the work premises.

Provide:

• EYEWASH - Eyewash fountains should be provided in areas where there is any possibility that workers could be exposed to the substances; this is irrespective of the recommendation involving the wearing of eye protection.

• QUICK DRENCH - Facilities for quickly drenching the body should be provided within the immediate work area for emergency use where there is a possibility of exposure. [Note: It is intended that these facilities provide a sufficient quantity or flow of water to quickly remove the substance from any body areas likely to be exposed. The actual determination of what constitutes an adequate quick drench facility depends on the specific circumstances. In certain instances, a deluge shower should be readily available, whereas in others, the availability of water from a sink or hose could be considered adequate.] (NIOSH, 2024)

Respiratory protection: For nuisance exposures use type P95 (US) or type P1 (EU EN 143) particle respirator. For higher level protection use type OV/AG/P99 (US) or type ABEK-P2 (EU EN 143) respirator cartridges. Use respirators and components tested and approved under appropriate government standars such as NIOSH (US) or CEN (EU).

Body protection: Complete suit protecting against chemicals, the type of protective equipment must be selected according to the concentration and amount of dangerous substance at the specific workplace.

Skin protection: Handle with gloves. gloves must be inspected prior to use. Use proper glove removal technique (without touching glove's outer surface) to avoid skin contact with this product. Dispose of contaminated gloves after use in accordance with applicable laws and good laboratory practices. Wash and dry hands.

Wear appropriate personal protective clothing to prevent skin contact.

For more Personal Protective Equipment (PPE) (Complete) data for 4-METHOXYPHENOL (7 total), please visit the HSDB record page.

Important additional information about respirator selection

NO open flames. Closed system, dust explosion-proof electrical equipment and lighting. Prevent deposition of dust.

PREVENT DISPERSION OF DUST!

Use local exhaust or breathing protection.

Protective gloves. Protective clothing.

Wear safety goggles.

Do not eat, drink, or smoke during work.

Hydroquinone monomethyl ether appears as pink crystals or white waxy solid. (NTP, 1992)

Dry Powder; Large Crystals; Liquid

Colorless to white, waxy solid with an odor of caramel & phenol; [NIOSH]

WHITE-TO-TAN SOLID IN VARIOUS FORMS WITH CHARACTERISTIC ODOUR.

Colorless to white, waxy solid with an odor of caramel & phenol.

White waxy solid

White to tan, flaky, crystalline substance

Colorless to white, waxy solid

Odor of caramel and phenol

475 °F at 760 mmHg (NTP, 1992)

243.00 to 245.00 °C. @ 760.00 mm Hg

246 °C @760 [mm Hg]

126.5 °F (NTP, 1992)

126.5 °F

269.6 °F (NTP, 1992)

270 °F (132 °C) (Open Cup)

132 °C o.c.

270 °F (open cup)

(oc) 270 °F

Soluble (NTP, 1992)

In water, 19,500 mg/L at 25 °C

In water, 40,000 mg/L at 25 °C

Soluble in benzene, carbon tetrachloride; very soluble in ethanol, ether

Readily soluble in acetone and ethyl acetate.

40 mg/mL at 25 °C

Solubility in water, g/100ml at 25 °C: 4

(77 °F): 4%

1.55 at 68 °F (NTP, 1992) - Denser than water; will sink

1.55 at 20 °C/20 °C

1.6 g/cm³

1.55 @ 20°C

4.3 (Air = 1)

Relative vapor density (air = 1): 4.3

less than 0.01 mmHg (NIOSH, 2024)

0.0083 [mmHg]

6.75X10-3 mm Hg at 20 °C

<0.01 mmHg

log Kow = 1.41 at 25 °C

790 °F (NTP, 1992)

790 °F (421 °C)

Sensitive to moisture. Water soluble.

Phenols and Cresols

HYDROQUINONE MONOMETHYL ETHER can react with oxidizing materials. (NTP, 1992)

Strong oxidizers, strong bases, acid chlorides, acid anhydrides.

Strong oxidizers, strong bases, acid chlorides, acid anhydrides

The CIR Expert Panel concluded that p-Hydroxyanisole is safe for use in nail adhesives and in artificial nail coatings, as a polymerization inhibitor, that are cured by LED light; and unsafe for use in all other cosmetics due to dermal depigmentation potential.

Safe for use in cosmetics, with qualifications

The ingredient is unsafe for use in cosmetics

IDENTIFICATION AND USE: 4-Methoxyphenol (4-MP) is available as a colorless to white, waxy solid or white to tan, flaky, crystalline substance with the odor of caramel and phenol. It is used as an inhibitor for acrylic monomers and acrylonitirles, as a stabilizer for chlorinated hydrocarbons and ethyl cellulose, as an ultraviolet inhibitor, as a chemical intermediate in the manufacture of antioxidants, pharmaceuticals, plasticizers, and dyestuffs. It is also used as a medication for dyschromias, especially hyperpigmentation often in combination with Tretinoin (Solage). HUMAN EXPOSURE AND TOXICITY: In 11 of the 16 patients (69%; 95% confidence interval [CI], 41%-89%) total depigmentation was achieved using the 4-MP cream. Onset of depigmentation was between 4 and 12 months. Mild burning or itching was reported with the cream in 4 cases (25%). Of the 11 patients who responded to the 4-MP cream, 4 had recurrence of pigmentation (relapse rate of 36%; 95% CI, 11%-69%) after a treatment-free period of 2 to 36 months. Excessive application of 4-MP, can result in marked redness, peeling, discomfort, or hypopigmentation. Oral ingestion of the drug may lead to the same adverse effects as those associated with excessive oral intake of vitamin A (hypervitaminosis A). In a vinylidene chloride plant 2 out of 8 process workers handling hydroquinone monomethyl ether developed depigmentation (occupational leukoderma) of skin of forearms and in 1 of them depigmentation of skin of forehead. Report of the follow-up of 2 cases of leukodermia (vitiligo) following exposure to 4-MP described 8 years previously and survey of 169 men exposed to 4-MP or paratertiary-amyl-phenol or both revealed that repigmentation of a significant degree was found in one man and of a limited degree in the other. Screening by means of the Wood's light technique (an ultra-violet light which is absorbed by normally pigmented skin and reflected by non-pigmented skin) of the 169 men surveyed in the same plant revealed no cases of leukoderma attributed to exposure to 4-MP in 148 men tested or in the 129 men exposed to paratertiary-amyl-phenol. In regards to possible genotoxicity, results from cytogenetic analysis show that the salt of 4-MP (p-methoxyphenol phosphate) induced the decrease of numerical and structural chromosome aberration after the first passage of the treated cells. In terms of the results obtained by cytogenetic analysis the reduction of genetic instability seems to remain constant from the first to the sixth passage in the cell cultures treated with p-methoxyphenol phosphate associated to benzo(a)pyrene. ANIMAL STUDIES: Rabbit studies with 4-MP have shown that it can cause considerable necrosis if exposure is not limited to 1 day. Prolonged contact can cause a severe burn. There is also indication that the material is absorbed in toxic amounts when in solution, especially through abraded skin. Acute parenteral poisoning in rabbits included paralysis and anoxia at lower doses and CNS depression at high doses. 4-MP caused depigmentation of the skin when applied topically to guinea pigs (within 5 to 10 days of treatment) and miniature pigs. In a dermal teratology study in rabbits, there were no statistically significant differences in fetal malformation data; however marked hydrocephaly with visible doming of the head was observed in one mid-dose litter (12 and 0.06 mg/kg or 132 and 0.66 mg/sq m of 4-MP and tretinoin, respectively. 4-MP does not appear to be carcinogenic when applied topically. In studies with 5% or 10% 4-MP (0.02 mL) twice a week between the shoulder blades of mice (for 93 weeks) or interior ears of rabbits, there was no significant decrease in survival rates, or tumor incidence compared to controls. Tumors were evident when 4-MP was administered in the diet of F344 rats (30 male and 30 females) administered diets of 2% 4-MP for 104 weeks. Histopathological findings in the 4-MP case included atypical hyperplasias (male, 67%, female, 37%), papillomas (50%, 23%) and squamous-cell carcinomas (77%, 20%) in the forestomach. 4-MC induced forestomach papillomas (70%, 93%) and squamous-cell carcinomas (53%, 37%), also glandular stomach submucosal hyperplasias (90%, 93%), adenomas (100%, 100%) and adenocarcinomas (57%, 47%), with ulceration or erosion. No genotoxic effects were observed when 4-MP was tested in Salmonella typhimurium TA98, TA100, TA1535, and TA1537 or in rats exposed dermally for 6 months.

The substance can be absorbed into the body by ingestion.

inhalation, skin absorption, ingestion, skin and/or eye contact

Redness. Burning sensation. Pain.

Redness. Pain.

irritation eyes, skin, nose, throat, upper respiratory system; eye, skin burns; central nervous system depression

Eyes, skin, respiratory system, central nervous system

LD50 Rat oral 1600 mg/kg

LD50 Mouse ip 250 mg/kg

LD50 Rabbit ip 720-790 mg/kg

Tests were carried out in cultured Chinese hamster ovary (CHO) cells (line CHO-AA8-4) and in X-irradiated Syrian hamster embryo cells (SHE) to investigate the effects of butylated-hydroxyanisole (BHA) on the metabolism and mutagenic activity of benzo(a)pyrene (BaP) and to compare them with those induced by butylated-hydroxytoluene (BHT) and p-methoxyphenol (PMO). Feeder Syrian hamster embryo cells were cocultured with target Chinese hamster ovary cells to provide metabolic transformation of benzo(a)pyrene. The mutagenicity of benzo(a)pyrene in target Chinese hamster ovary cells was reduced by up to 60% by pretreatment with p-methoxyphenol, butylated-hydroxyanisole, or butylated-hydroxytoluene. In Syrian hamster ovary cells, the antioxidants tested inhibited metabolism with reduction in levels of water soluble benzo(a)pyrene glucuronide conjugates in the extracellular medium and apparent increase in levels of intracellular monophenols. As a result of the antioxidant inhibited formation of reactive, electrophilic benzo(a)pyrene metabolites, there was reduction in the binding of benzo(a)pyrene to nuclear macromolecules, especially to DNA.

The modifying effects of para-methoxyphenol second stage treatment on N-methyl-N'-nitro-N-nitrosoguanidine initiated rat forestomach carcinogenesis were investigated. Groups of 15 6 week old male F344 rats were given a single intragastric administration of 150 mg/kg body wt N-methyl-N'-nitro-N-nitrosoguanidine and starting 1 week later were administered powdered diet containing 2.0, 1.0, 0.5, 0.25 or 0% para-methoxyphenol until week 52. para-methoxyphenol caused epithelial damage and hyperplasia in a dose-dependent manner in the forestomach epithelium but nevertheless was not associated with any increase in the incidence of either papillomas or squamous cell carcinomas. Stimulation of cell proliferation does not necessarily correlate with promotion in the second stage of two-stage forestomach carcinogenesis.

The modifying effects of five phenolic antioxidants on N-methyl-N-nitro-N-nitrosoguanidine (MNNG)-initlated forestomach and glandular stomach carcinogenesis were investigated in male F344 rats. Groups of 20 rats were given an intragastric dose of 150 mg/kg body weight N-methyl-N-nitro-N-nitrosoguanine and starting from 1 week later received diet supplemented with 0.8% catechol, 1.0% 2-tert-butyl-4-methylphenol, 1.5% p-tert-butylphenol, 1.5% methylhydroquinone, 1.5% 4-methoxyphenol, or basal diet alone for 51 wk. Further groups of 10-15 rats were maintained as controls without prior treatment with N-methyl-N-nitro-N-nitrosoguanine. The incidences of squamous cell carcinoma of the forestomach in N-methyl-N-nitro-N-nitrosoguanine-treated animals were significantly elevated by the diets containlng catechol (P less than 0.001), 2-tert-butyl-4-methylphenol (P less than 0.001), or p-tert-butylphenol (P less than 0.01), while the development of carcinoma in situ was inhibited by 4-methoxyphenol (P less than 0.01). Treatment with catechol, 2-tert-butyl-4-methylphenol, p-tert-butylphenol, or 4-methoxyphenol alone induced forestomach hyperplasia at incidences of 86.7, 40, 93.3, and 100%, respectively. In the pyloric region of the glandular stomach, the development of adenomatous hyperplasia and adenocarcinoma after N-methyl-N-nitro-N-nitrosoguanine treatment was significantly enhanced by diet containing catechol (P less than 0.001). Moreover, treatment with catechol alone induced 100% adenomatous hyperplasia and induced adenocarcinoma in 20% of animals. ... While antioxidants causing proliferation in forestomach epithelium can markedly enhance carcinogenesis in this tissue, others displaying the same or greater potential for generating a hyperplastic response, like 4-methoxyphenol can exert an inhibitory effect. In addition, it was shown that catechol is an unequivocal glandular stomach carcinogen also possessing strong enhancing activity for N-methyl-N-nitro-N-nitrosoguanine-induced lesion development.

The chemopreventive effect of 40 and 80% maximum tolerated dose (MTD) levels of ascorbylpalmitate (AP), carbenoxolone (CBX), dimethylfumarate (DMF) and p-methoxyphenol (p-MP) administrated in the diet before and during initiation and postinitiation phases of azoxymethane (AOM)-induced colon carcinogenesis was studied in male F344 rats. The MTD levels of AP, CBX, DMF and p-MP were determined in male F344 rats and found to be 5000, 1500, 1000 and 1000 ppm, respectively, in modified AIN-76A diet. Based on these MTD values, 40 and 80% MTD levels of each agent was tested for their efficacy in colon carcinogenesis. At 5 weeks of age, groups of animals were fed the control (modified AIN-76A diet or diets containing 40 and 80% MTD levels of each AP, CBX, DMF and p-MP. At 7 weeks of age, all animals, except those in the vehicle (normal saline) treated groups, were given two weekly s.c. injections of AOM at a dose rate of 15 mg/kg body weight/week. All groups were continued on their respective dietary regimen until the termination of the experiment 52 weeks after the carcinogen treatment. Colonic tumors were evaluated histopathologically. The results indicate that dietary administration of 40% MTD of AP significantly inhibited multiplicities (tumor/animal) of noninvasive and total (invasive plus noninvasive) adenocarcinoma of the colon (P < 0.05) and 80% MTD of AP significantly inhibited the incidence (% animals with tumors) and the multiplicities of invasive and total adenocarcinomas of the colon (P < 0.01). Dietary CBX at 40 and 80% MTD levels suppressed the incidence and multiplicities of invasive and total adenocarcinomas (P < 0.05 to 0.001) whereas 40 and 80% MTD of DMF and p-MP had significantly inhibited invasive adenocarcinoma incidence and multiplicity (P < 0.05 to 0.001). However, DMF and p-MP had no significant effect on noninvasive and total adenocarcinoma incidence and multiplicity (P > 0.05). These results suggest that AP and CBX possess potential chemopreventive properties against colon cancer.

For more Interactions (Complete) data for 4-METHOXYPHENOL (11 total), please visit the HSDB record page.

Immediate first aid: Ensure that adequate decontamination has been carried out. If patient is not breathing, start artificial respiration, preferably with a demand-valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR as necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on left side (head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Phenols and related compounds/

Basic treatment: Establish a patent airway (oropharyngeal or nasopharyngeal airway, if needed). Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if necessary. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . Monitor for shock and treat if necessary ... . Anticipate seizures and treat if necessary ... . For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with 0.9% saline (NS) during transport ... . Administer activated charcoal ... . Dilution may be contraindicated because if may increase absorption. Do not use emetics. Cover skin burns with dry, sterile dressings after decontamination ... . Maintain body temperature. /Phenols and related compounds/

Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in severe respiratory distress. Positive pressure ventilation techniques with a bag valve mask device may be beneficial. Consider drug therapy for pulmonary edema ... . Monitor cardiac rhythm and treat arrhythmias if necessary ... . Start IV administration of D5W /SRP: "To keep open", minimal flow rate/. Use 0.9% saline (NS) or lactated Ringer's (LR) if signs of hypovolemia are present. For hypotension with signs of hypovolemia, administer fluid cautiously. Consider vasopressors if patient is hypotensive with a normal fluid volume. Watch for signs of fluid overload ... . Administer 1% solution methylene blue if patient is symptomatic with severe hypoxia, cyanosis, and cardiac compromise not responding to oxygen. ... Treat seizures with diazepam or lorazepam. ... Use proparacaine hydrochloride to assist eye irrigation ... . /Phenols and related compounds/

/HUMAN EXPOSURE STUDIES/ /The purpose of this study/ was to evaluate the long-term effectiveness and safety of a combination therapy consisting of topical 4-methoxyphenol (4-MP) cream and Q-switched ruby (QSR) laser in 16 patients with vitiligo universalis. In a retrospective study, patient record forms were evaluated. Data were collected regarding history as well as physical and histologic examination. The patients came to the institute for a follow-up visit after a treatment-free period of 2 to 36 months. Thirteen patients received both therapies. Three patients only used the cream. None of the areas was treated by the cream and QSR laser at the same time. In 11 of the 16 patients (69%; 95% confidence interval [CI], 41%-89%) total depigmentation was achieved using the 4-MP cream. Onset of depigmentation was between 4 and 12 months. Four of the 5 patients who did not respond to the 4-MP cream had successful depigmentation with the QSR laser. Mild burning or itching was reported with the cream in 4 cases (25%). Of the 11 patients who responded to the 4-MP cream, 4 had recurrence of pigmentation (relapse rate of 36%; 95% CI, 11%-69%) after a treatment-free period of 2 to 36 months. In 9 of the 13 patients (69%; 95% CI, 39%-91%) total depigmentation was achieved after QSR laser therapy. Onset of depigmentation was between 7 and 14 days after the treatment. Three of the 4 unresponsive patients showed total depigmentation after application of the 4-MP cream. No side effects were observed. Of the 9 patients who responded to QSR laser therapy, 4 had recurrence of pigmentation (relapse rate of 44%; 95% CI, 14%-79%) after a treatment-free period of 2 to 18 months. These patients had a negative Koebner phenomenon. Patients should be warned that repigmentation may occur, even after total depigmentation has been achieved.

/HUMAN EXPOSURE STUDIES/ 4-Hydroxyanisole is a depigmenting agent which has been shown to have activity against malignant melanoma when given intra-arterially in /humans/. An intravenous dose escalation study has been carried out with the aim of obtaining maximum plasma concentrations in a 5 day schedule. Eight patients entered this study which was stopped because of drug toxicity after 3 patients had been treated at the third dose escalation of 15 g/sq m. Two patients had WHO grade 4 liver and one also grade 4 renal toxicity and another had grade 4 hemoglobin toxicity. Extrapolated plateau plasma levels between 112 and 860 umol/L were obtained, which in vitro studies suggested would be cytotoxic.

/SIGNS AND SYMPTOMS/ If Solage solution is applied excessively, no more rapid or better results will be obtained and marked redness, peeling, discomfort, or hypopigmentation may occur. Oral ingestion of the drug may lead to the same adverse effects as those associated with excessive oral intake of vitamin A (hypervitaminosis A). ...

/CASE REPORTS/ In a vinylidene chloride plant 2 out of 8 process workers handling hydroquinone monomethyl ether developed depigmentation (occupational leucoderma) of skin of forearms and in 1 of them depigmentation of skin of forehead.

For more Human Toxicity Excerpts (Complete) data for 4-METHOXYPHENOL (10 total), please visit the HSDB record page.

/LABORATORY ANIMALS: Acute Exposure/ ... Rabbit studies with hydroquinone monomethyl ether have shown that the undiluted material can cause considerable necrosis if exposure is not limited to 1 day. Prolonged contact can cause a severe burn ... . There is also indication ... that the material was absorbed in toxic amounts when in solution, especially through abraded skin.

/LABORATORY ANIMALS: Acute Exposure/ The gross signs of acute parenteral poisoning /in rabbits/ included paralysis and anoxia at lower doses and /CNS depression/ at high doses.

/LABORATORY ANIMALS: Acute Exposure/ A vitiligo-like depigmentation was produced by topical application once daily of p-hydroxyanisole 20 to back of ears of guinea pigs.

/LABORATORY ANIMALS: Acute Exposure/ ...Material was not a skin sensitizer in guinea pigs.

For more Non-Human Toxicity Excerpts (Complete) data for 4-METHOXYPHENOL (22 total), please visit the HSDB record page.

EPA has released the first beta version (version 0.5) of the Interactive Chemical Safety for Sustainability (iCSS) Dashboard. The beta version of the iCSS Dashboard provides an interactive tool to explore rapid, automated (or in vitro high-throughput) chemical screening data generated by the Toxicity Forecaster (ToxCast) project and the federal Toxicity Testing in the 21st century (Tox21) collaboration. /The title compound was tested by ToxCast and/or Tox21 assays; Click on the "Chemical Explorer" button on the tool bar to see the data./[USEPA; ICSS Dashboard Application; Available from, as of December 8, 2014: http://actor.epa.gov/dashboard/]

EC50; Species: Daphnia magna (Water flea); Conditions: freshwater, static, 19-20 °C, pH 7.4-7.8, dissolved oxygen 7.7-8.6 at test start and 5.5-6.1 at test end; Concentration: 2.2 mg/L for 48 hr; Effect: immobilization

LC50; Species: Daphnia magna (Water flea) age < or =24 hr; Conditions: freshwater, static, 20-22 °C, pH 7.6-7.7; Concentration: 19000 ug/L for 24 hr /formulated product/

LC50; Species: Pimephales promelas (Fathead minnow); Conditions: freshwater, static, 19-20 °C, pH 7.4-7.8; Concentration: 55 mg/L for 96 hr

LC50; Species: Pimephales promelas (Fathead minnow) juvenile, age 26-34 days; Conditions: freshwater, flow through, 25 °C, pH 7.8, hardness 45 mg/L CaCO3, alkalinity 42 mg/L CaCO3; Concentration: 84300 ug/L for 96 hr /> or = 95% purity/

For more Ecotoxicity Values (Complete) data for 4-METHOXYPHENOL (9 total), please visit the HSDB record page.

4-Methoxyphenol's production and use in the manufacture of antioxidants, pharmaceuticals, plasticizers, dyestuffs, as a stabilizer for chlorinated hydrocarbons and ethyl cellulose, and as an inhibitor for acrylic monomers and acrylonitriles may result in its release to the environment through various waste streams. 4-Methoxyphenol is reported to occur in licorice root and sesame seed. If released to air, a vapor pressure of 6.75X10-3 mm Hg at 20 °C indicates 4-methoxyphenol will exist solely as a vapor in the atmosphere. Vapor-phase 4-methoxyphenol will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in air is estimated to be 4 hrs. By analogy to phenol, 4-methoxyphenol absorbs at wavelengths >290 nm and, therefore, may be susceptible to direct photolysis by sunlight. If released to soil, 4-methoxyphenol is expected to have high mobility based upon Koc values of 55.7 and 90. Volatilization from moist soil surfaces is not expected to be an important fate process based upon an estimated Henry's Law constant of 5.7X10-8 atm-cu m/mole. 4-Methoxyphenol is not expected to volatilize from dry soil surfaces based upon its vapor pressure. Utilizing the Japanese MITI test, 86% of the Theoretical BOD was reached in 4 weeks indicating that 4-methoxyphenol is readily biodegradable. Complete biodegradation of 4-methoxyphenol under aerobic conditions within 8 days using a soil inoculum suggests that biodegradation may be an important environmental fate process in soil. If released into water, 4-methoxyphenol is not expected to adsorb to suspended solids and sediment based upon the Koc values. River die-away tests have determined half-lives of 22.5 hours to about 5-6 days. Volatilization from water surfaces is not expected to be an important fate process based upon this compound's estimated Henry's Law constant. An estimated BCF of 4 suggests the potential for bioconcentration in aquatic organisms is low. Hydrolysis is not expected to be an important environmental fate process since this compound lacks functional groups that hydrolyze under environmental conditions. 4-Methoxyphenol can be degraded in natural waters through indirect photolysis. Occupational exposure to 4-methoxyphenol may occur through inhalation and dermal contact with this compound at workplaces where 4-methoxyphenol is produced or used. Use data indicate that the general population may be exposed to 4-methoxyphenol via dermal contact with topical pharmaceuticals containing 4-methoxyphenol. (SRC)

4-Methoxyphenol is reported to occur in licorice root and sesame seed(1).

4-Methoxyphenol's production and use in the manufacture of antioxidants, pharmaceuticals, plasticizers, dyestuffs, as a stabilizer for chlorinated hydrocarbons and ethyl cellulose, and as an inhibitor for acrylic monomers and acrylonitriles(1) may result in its release to the environment through various waste streams(SRC).

EC50; Species: Daphnia magna (Water flea); Conditions: freshwater, static, 19-20 °C, pH 7.4-7.8, dissolved oxygen 7.7-8.6 at test start and 5.5-6.1 at test end; Concentration: 2.2 mg/L for 48 hr; Effect: immobilization

LC50; Species: Daphnia magna (Water flea) age < or =24 hr; Conditions: freshwater, static, 20-22 °C, pH 7.6-7.7; Concentration: 19000 ug/L for 24 hr /formulated product/

LC50; Species: Pimephales promelas (Fathead minnow); Conditions: freshwater, static, 19-20 °C, pH 7.4-7.8; Concentration: 55 mg/L for 96 hr

LC50; Species: Pimephales promelas (Fathead minnow) juvenile, age 26-34 days; Conditions: freshwater, flow through, 25 °C, pH 7.8, hardness 45 mg/L CaCO3, alkalinity 42 mg/L CaCO3; Concentration: 84300 ug/L for 96 hr /> or = 95% purity/

For more Ecotoxicity Values (Complete) data for 4-METHOXYPHENOL (9 total), please visit the HSDB record page.

4-Methoxyphenol's production and use in the manufacture of antioxidants, pharmaceuticals, plasticizers, dyestuffs, as a stabilizer for chlorinated hydrocarbons and ethyl cellulose, and as an inhibitor for acrylic monomers and acrylonitriles may result in its release to the environment through various waste streams. 4-Methoxyphenol is reported to occur in licorice root and sesame seed. If released to air, a vapor pressure of 6.75X10-3 mm Hg at 20 °C indicates 4-methoxyphenol will exist solely as a vapor in the atmosphere. Vapor-phase 4-methoxyphenol will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in air is estimated to be 4 hrs. By analogy to phenol, 4-methoxyphenol absorbs at wavelengths >290 nm and, therefore, may be susceptible to direct photolysis by sunlight. If released to soil, 4-methoxyphenol is expected to have high mobility based upon Koc values of 55.7 and 90. Volatilization from moist soil surfaces is not expected to be an important fate process based upon an estimated Henry's Law constant of 5.7X10-8 atm-cu m/mole. 4-Methoxyphenol is not expected to volatilize from dry soil surfaces based upon its vapor pressure. Utilizing the Japanese MITI test, 86% of the Theoretical BOD was reached in 4 weeks indicating that 4-methoxyphenol is readily biodegradable. Complete biodegradation of 4-methoxyphenol under aerobic conditions within 8 days using a soil inoculum suggests that biodegradation may be an important environmental fate process in soil. If released into water, 4-methoxyphenol is not expected to adsorb to suspended solids and sediment based upon the Koc values. River die-away tests have determined half-lives of 22.5 hours to about 5-6 days. Volatilization from water surfaces is not expected to be an important fate process based upon this compound's estimated Henry's Law constant. An estimated BCF of 4 suggests the potential for bioconcentration in aquatic organisms is low. Hydrolysis is not expected to be an important environmental fate process since this compound lacks functional groups that hydrolyze under environmental conditions. 4-Methoxyphenol can be degraded in natural waters through indirect photolysis. Occupational exposure to 4-methoxyphenol may occur through inhalation and dermal contact with this compound at workplaces where 4-methoxyphenol is produced or used. Use data indicate that the general population may be exposed to 4-methoxyphenol via dermal contact with topical pharmaceuticals containing 4-methoxyphenol. (SRC)

4-Methoxyphenol is reported to occur in licorice root and sesame seed(1).

4-Methoxyphenol's production and use in the manufacture of antioxidants, pharmaceuticals, plasticizers, dyestuffs, as a stabilizer for chlorinated hydrocarbons and ethyl cellulose, and as an inhibitor for acrylic monomers and acrylonitriles(1) may result in its release to the environment through various waste streams(SRC).

TERRESTRIAL FATE: Based on a classification scheme(1), experimentally derived Koc values of 55.7(2) and 90(3), indicates that 4-methoxyphenol is expected to have high mobility in soil(SRC). Volatilization of 4-methoxyphenol from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 5.7X10-8 atm-cu m/mole(SRC), based upon its vapor pressure, 6.73X10-3 mm Hg(4), and water solubility, 1.95X10+4 mg/L(5). 4-Methoxyphenol is not expected to volatilize from dry soil surfaces(SRC) based upon an its vapor pressure(4). An 86% of theoretical BOD using activated sludge in the Japanese MITI test indicates that 4-methoxyphenol is readily biodegradable(6). Complete biodegradation of 4-methoxyphenol under aerobic conditions within 8 days using a soil inoculum(7) suggests that biodegradation may be an important environmental fate process in soil(SRC).

AQUATIC FATE: Based on a classification scheme(1), Koc values of 55.7(2) and 90(3), indicates that 4-methoxyphenol is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is not expected(4) based upon an estimated Henry's Law constant of 5.7X10-8 atm-cu m/mole(SRC), derived from its vapor pressure, 6.75X10-3 mm Hg(5), and water solubility, 1.95X10+4 mg/L(6). According to a classification scheme(7), an estimated BCF of 4(SRC), from its log Kow of 1.41(8) and a regression-derived equation(9), suggests the potential for bioconcentration in aquatic organisms is low. 4-Methoxyphenol is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(4). In general, phenols in surface waters exposed to sunlight react with photo-oxidants (such as hydroxyl radicals, peroxy radicals and singlet oxygen) with a half-life on the order of 13 days(10). The indirect photolysis of 4-methoxyphenol in natural water has been demonstrated(5,11). An 86% of theoretical BOD using activated sludge in the Japanese MITI test indicates that 4-methoxyphenol is readily biodegradable(12). River die-away tests have determined half-lives of 22.5 hours to about 5-6 days(13,14).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 4-methoxyphenol, which has a vapor pressure of 6.75X10-3 mm Hg at 20 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase 4-methoxyphenol 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 4 hours(SRC), calculated from its rate constant of 9.5X10-11 cu cm/molecule-sec at 21 °C(3). Phenol absorbs at wavelengths >290 nm(4) and therefore, by analogy, 4-methoxyphenol may be susceptible to direct photolysis by sunlight(SRC). 4-Methoxyphenol has been observed to photodegrade in pure water exposed to sunlight(5).

AEROBIC: 4-Methoxyphenol, present at 100 mg/L, reached 86% of its theoretical BOD in 4 weeks using an activated sludge inoculum at 30 mg/L in the Japanese MITI test which classified the compound as readily biodegradable(1). An acclimated mixed bacterial population reached 57% of the theoretical BOD after 5 days(2). Varying concentrations of an acclimated mixed bacterial population resulted in biodegradation rate constants of 4.2X10-2/day, 5.0X10-2/day, 8.0X10-2/day, 1.9X10-1/day, and 2.5X10-1/day for bacterial concentrations of 2.3X10+4, 2.3X10+5, 2.3X10+6, 2.3X10+7, and 2.3X10+8 cells/L, respectively(3). 4-Methoxyphenol was biodegraded by three activated sludges with rate constants of 7.88X10-4/hr, 4.03X10-4/hr, and 3.35X10-3/hr for a non-adapted sludge, a phenol-adapted sludge, and a cresol-adapted sludge, respectively(4). Using spectrophotometric evidence, aniline-adapted activated sludge degraded 4-methoxyphenol mainly via an ortho cleavage pathway(5); phenol- and m-cresol-adapted activated sludges degraded 4-methoxyphenol mainly via a meta cleavage pathway(5). 4-Methoxyphenol, at a concentration of 0.27 mg/L was removed 95% in 1 day and 89.6% in 2 days using an activated sludge inoculum(6).

AEROBIC: An initial concentration of 4-methoxyphenol of 2 mg/L was biodegraded 45.9% in Songhua River water (China) in 5 days at a temperature of 15-20 °C, pH 6.8-7 and dissolved oxygen of 8.0 mg/L(1). 4-Methoxyphenol had an aerobic biodegradation rate of 0.74/day in Songhua River water from Jilin Province, China, corresponding to a half-life of 22.5 hours(2). Natural river and pond water from five sites was incubated with 1 mg/L of 4-methoxyphenol; microbial transformation rate constants of 1.1X10-11 to 3.5X10-11 L/organism hr were measured for pond water(3). River water had a rate constant of 3.1X10-11 L/organism hr(3). 4-Methoxyphenol is oxidized during biodegradation to the corresponding catechol(3). Using a soil suspension inoculum, 4-methoxyphenol, at 15 mg/L, was completely biodegraded (through cleavage of the aromatic ring) within 8 days(4).

ANAEROBIC: 4-Methoxyphenol (concentration = 50 ug carbon) was completely mineralized within 1 week under anaerobic conditions using a 10% sludge inoculum from a primary digester(1). 4-Methoxyphenol was degraded anaerobically 30-75% incubated 96 days in marine sediment from Oresund, Denmark; 81% degadation occured using fresh water incubated 56 days with <2 week lag time(2). Using sewage sludge, degradation was >75% incubated 56 days; using in fresh water from a water-logged swamp, degradation was >75% incubated 56 days(2). 4-Methoxyphenol was found inherently biodegradable in an anaerobic screening test in which 90% degradation, measured as methane production, was reached after 7 days of incubation(3).

The rate constant for the vapor-phase reaction of 4-methoxyphenol with photochemically-produced hydroxyl radicals has been measured as 9.5X10-11 cu cm/molecule-sec at 21 °C(1). This corresponds to an atmospheric half-life of about 4 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(2). 4-Methoxyphenol is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(3). Phenol absorbs at wavelengths >290 nm(4) and therefore, by analogy, 4-methoxyphenol may be susceptible to direct photolysis by sunlight(SRC). 4-Methoxyphenol has been observed to photodegrade in pure water exposed to sunlight(5). In general, phenols in surface waters exposed to sunlight react with photo-oxidants (such as hydroxyl radicals, peroxy radicals and singlet oxygen) with a half-life on the order of 13 days(6). The indirect photolysis of 4-methoxyphenol was demonstrated using natural water and irradiation much stronger than sunlight which resulted in near complete degradation in 4 hours and half-lives of 0.4 hours (at pH 7 and pH 8) and 0.5 hours at pH 9(7,8). The rate constant for the reaction of hydroxyl radicals in aqueous solutions at pH 9 is 2.6X10+10 L/mol-sec(9); this corresponds to an aquatic half-life of about 30 days at an aquatic concentration of 1X10-17 hydroxyl radicals per liter(10). A rate constant of 6.67X10+8/mole sec was measured for the reaction of 4-methoxyphenol with singlet oxygen(11).

An estimated BCF of 4 was calculated in fish for 4-methoxyphenol(SRC), using a log Kow of 1.41(1) and a regression-derived equation(2). According to a classification scheme(3), this BCF suggests the potential for bioconcentration in aquatic organisms is low(SRC).

An experimental Koc of 55.7 was determined for adsorption to Brookston clay loam (pH 5.7, 8.8% organic content, 22.22 cation exchange capacity)(1). Using a Lucera-clay sample (0.5% organic carbon, 11 meq/100 g cation exchange capacity), a K value of 0.45 was measured(2) which corresponds to a Koc value of 90(3). According to a classification scheme(4), these Koc values suggest that 4-methoxyphenol is expected to have high mobility in soil(SRC).

The Henry's Law constant for 4-methoxyphenol is estimated as 5.7X10-8 atm-cu m/mole(SRC) derived from its vapor pressure, 6.75X10-3 mm Hg(1), and water solubility, 1.95X10+4 mg/L(2). This Henry's Law constant indicates that 4-methoxyphenol is expected to be essentially nonvolatile from water surfaces(3). 4-Methoxyphenol's estimated Henry's Law constant indicates that volatilization from moist soil surfaces is not expected to occur(SRC). 4-Methoxyphenol is not expected to volatilize from dry soil surfaces based upon its vapor pressure(SRC).

4-Methoxyphenol was detected in one occurrence from wastewater from the pulp and paper industry(1). An unknown amount of 4-methoxyphenol was accidentally released into an unspecified river with p-nitrochlorobenzene causing extensive fish kills(2). 4-Methoxyphenol was detected in the particle emissions from a wood heater at concentrations of 0.38-3.04 mg/kg dry wood burned(3).

4-Methoxyphenol occurrences in plants(1).[Table#4892]

According to the 2012 TSCA Inventory Update Reporting data, 4 reporting facilities estimate the number of persons reasonably likely to be exposed in the United States manufacturing, processing, or use of 4-methoxyphenol may be as low as <10 workers per plant; the data may be greatly underestimated due to confidential business information (CBI) or unknown values(1).

NIOSH (NOES Survey 1981-1983) has statistically estimated that 250,087 workers (49,763 of these were female) were potentially exposed to 4-methoxyphenol in the US(1). Occupational exposure to 4-methoxyphenol may occur through dermal contact with this compound at workplaces where 4-methoxyphenol is produced or used. Use data indicate that the general population may be exposed to 4-methoxyphenol via dermal contact with topical pharmaceuticals containing 4-methoxyphenol(SRC).

SRP: 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 air, soil or water; effects on animal, aquatic and plant life; and conformance with environmental and public health regulations. If it is possible or reasonable use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination.

Symbol: Xn; R: 22-36-43; S: (2)-24/25-26-37/39-46