5-Amino-2-methylphenol

Cosmetic ingredients (4-Amino-2-Hydroxytoluene) -> CIR (Cosmetic Ingredient Review)

Hair dyeing

less than 1 mg/mL at 70 °F (NTP, 1992)

In water, 2,427 mg/L @ 25 °C /Estimated/

320 to 347 °F (sublimes) (NTP, 1992)

161 °C

0.00026 [mmHg]

2.6X10-4 mm Hg @ 25 °C /Estimated/

3-amino-6-methylphenol is a brown powder. (NTP, 1992)

Brown solid; [CAMEO] Slightly beige powder; [MSDSonline]

Warning

H315 (68.2%): Causes skin irritation [Warning Skin corrosion/irritation]

P261, P264, P264+P265, P271, P272, P273, P280, P302+P352, P304+P340, P305+P351+P338, P319, P321, P332+P317, P333+P317, P337+P317, P362+P364, P391, P403+P233, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 179 reports by companies from 18 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Warning

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

Chemical: Phenol, 5-amino-2-methyl-

Status: Active Update: 13-09-2022 https://echa.europa.eu/registration-dossier/-/registered-dossier/24086

Phenol, 5-amino-2-methyl-: Does not have an individual approval but may be used as a component in a product covered by a group standard. It is not approved for use as a chemical in its own right.

A mutagen; Causes somnolence and ataxia in lethal-dose feeding studies of rats; [RTECS] Induces goiter, hypothyroidism, and liver injury in feeding studies of rats for 13 weeks; No difference in chromosomal aberrations between controls and subjects who dyed their hair with 2-hydroxy-4-aminotoluene 13 times at intervals of 3-6 weeks; Very weak skin sensitizer in guinea pigs; Did not induce photosensensitization in guinea pigs; [HSDB] A skin, eye, and mucous membrane irritant; [CAMEO] An irritant; [MSDSonline]

Skin Irrit. 2 (68.2%)

Skin sensitisation - category 1

Serious eye damage/eye irritation - Category 2B

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.

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.

RECOMMENDED RESPIRATOR: Where the neat test chemical is weighed and diluted, wear a NIOSH-approved half face respirator equipped with an organic vapor/acid gas cartridge (specific for organic vapors, HCl, acid gas and SO2) with a dust/mist filter. (NTP, 1992)

Safety glasses, adequate ventilation.

LD50 Quail oral 750 mg/kg

LD50 Red-winged blackbird (Agelaius phoeniceus) oral >1000 mg/kg

LD50 Starling (Sturnus vulgaris) oral >1000 mg/kg

LD50 House sparrow (Passer domesticus) oral 562 mg/kg

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=2835-95-2]

/HUMAN EXPOSURE STUDIES/ Ten volunteers (males and females) each had their hair dyed 13 times at intervals of 3-6 wk. Each volunteer used a single commercial preparation throughout the study. /Five of the preparations contained 2-hydroxy-4-aminotoluene./ ...Lymphocytes of the hair-dyed volunteers and of ten controls matched for age and sex were scored for chromosomal aberrations. The incidence of aberrations did not differ significantly between the controls and the hair-dyed volunteers at any of the nine sampling times.

/HUMAN EXPOSURE STUDIES/ A modified Draize repeat insult patch test (RIPT) procedure was used to evaluate the irritation and sensitization potential of two aqueous solutions, each containing 2% of 4-amino-2-hydroxytoluene as supplied. An initial challenge (100% applied for 1 hr) was made to aid in the interpretation of the challenge following the rest period. For the induction exposure, semiocclusive patches containing 0.3 ml of the solution were applied to the same site on the upper arm of each subject on Mondays, Wednesdays, and Fridays for 3 consecutive weeks. The first solution for induction was a 3.0% v/v aqueous solution and the second was a 10% w/v aqueous solution. Patches were left in place for 24 hr and scored 48 or 72 hr after application. The challenge was made after a 2 wk nontreatment period. A patch containing 100% of the test solution was applied to a previously untreated site for 1 hr. Sites were scored 48 and 96 hr after application. Another challenge patch was also applied simultaneously to the induction site using the induction concentration. Twenty-three of the 27 subjects completed testing with the first solution. The initial challenge produced 21 negative and 5 slight reactions; the induction period elicited reactions from one subject only, who had a score of 4 (maximum=7) at the sixth induction patch and was subsequently patched on a different site. The challenge solution produced 20 negative, 2 slight (score of 1), and 1 significant (score of 3) reactions. The significant reaction was seen in the same subject who had reacted during the induction phase. No reactions were produced by the challenge patch applied to the induction site. A rechallenge was conducted with 11 of the subjects at a naive site on the upper back using a concentration of 25% of the test solution; 10 negative (including the 1 patient with the significant reaction at challenge) and 1 slight reactions were observed. /It was/ concluded that the test solution had produced one case of significant dermatitis, although it was not reproduced at rechallenge. Thirty-one subjects completed testing with the second solution. The initial challenge failed to produce a reaction in any of the subjects. During the induction period, very slight reactions (scores of 1 or less) were observed in 4 subjects and strong reactions (scores of up to 3 and 5) in two subjects. Challenge at a previously untreated site produced two slight reactions and one strong reaction (scores of 5 at both 48 and 96 hr), the latter being a delayed challenge due to residual reactions from the induction phase. The challenge patches applied to the induction site produced three slight and two strong reactions; however, only one of these five subjects had a reaction when challenged at a previously untreated site. A rechallenge of two subjects produced one negative and one significant response, the latter being from one of those with a strong reaction to challenge at the induction site. In the investigator's opinion, two cases of significant dermatitis had been observed, one each during challenge and rechallenge; therefore, these were cases of induced contact allergic eczema.

/LABORATORY ANIMALS: Acute Exposure/ The irritant effects on rabbit skin and eye mucosa, and the acute oral toxicity in rats were assessed for twelve compounds which are hair-dye constituents or chemically related aromatic amines, aminophenols, nitro derivatives or aromatic hydroxy derivatives. .../4-amino-2-hydroxytoluene was/ non-irritant /to rabbit skin/ at the concentrations studied. ...Only mild conjunctival reaction followed treatment with /4-amino-2-hydroxytoluene/... .

/LABORATORY ANIMALS: Acute Exposure/ Groups of 5 male and 5 female /CFY strain/ rats were /given a 10% suspension of 4-amino-2-hydroxytoluene in 0.5% aqueous gum tragacanth containing 0.05% anhydrous sodium sulfite./ ...All animals that died as well as those killed at the end of the study were subjected to autopsy exam. ...At necropsy of the rats that died, some darkening of liver and kidneys, darkening or pallor of the spleen, hemorrhages of the lungs and intestines, and injection of intestinal and mesenteric blood vessels were observed. The survivors did not have any abnormalities indicative of residual systemic effects.

/LABORATORY ANIMALS: Acute Exposure/ The acute dermal toxicity of 4-amino-2-hydroxytoluene was evaluated using six male and six female New Zealand white rabbits. The back of each rabbit was clipped free of hair and the animals were fitted with plastic collars to prevent oral ingestion of the compound. A dose of 5 g/kg 4-amino-2-hydroxytoluene (as a slurry with 3.0% acacia) was applied to the back of each rabbit with a gauze pad. The pads were left in place under semiocclusive conditions for 24 hr. The rabbits were observed for 7 days after patch removal. The 4-amino-2-hydroxytoluene did not produce any systemic/dermal toxicity at a dosage of 5 g/kg.

/LABORATORY ANIMALS: Subchronic or Prechronic Exposure/ ...The dietary administration of 4-amino-2-hydroxytoluene to rats at concentrations up to 3.0% for periods of 3-6 months can cause reduction in body weight, a slight anemia, and sporadic microfollicular goiter.

For more Non-Human Toxicity Excerpts (Complete) data for 5-AMINO-O-CRESOL (10 total), please visit the HSDB record page.

Basic treatment: Establish a patent airway. Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if needed. 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 normal saline during transport ... . Do not use emetics. For ingestion, rinse mouth and administer 5 ml/kg up to 200 ml of water for dilution if the patient can swallow, has a strong gag reflex, and does not drool ... . Cover skin burns with dry sterile dressings after decontamination ... . /Poison A and B/

Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in respiratory arrest. Positive pressure ventilation techniques with a bag valve mask device may be beneficial. Monitor cardiac rhythm and treat arrhythmias as necessary ... . Start an IV with D5W /SRP: "To keep open", minimal flow rate/. Use lactated Ringer's if signs of hypovolemia are present. Watch for signs of fluid overload. Consider drug therapy for pulmonary edema ... . For hypotension with signs of hypovolemia, administer fluid cautiously. Watch for signs of fluid overload ... . Treat seizures with diazepam (Valium) ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Poison A and B/

/Percutaneous absorption of 5-amino-o-cresol in a hair dye was studied under the conditions of usage. Radiolabeled 5-amino-o-cresol was added to a commercial dye containing 0.69% non-radioactive 5-amino-o-cresol; the mixture was applied to dry hair of three volunteers, worked in to the hair mass for 5-8 min, and rinsed off after an additional 20 min; the urine samples were collected for as long as radioactivity was detected, approximately 144 hr. The total urinary excretion of radioactivity was 0.2% with 50% of the radioactivity excreted in 24 hr./

/A/ ...series of experiments /compared/ the skin permeability of a number of hair dyes obtained in two different laboratories. /Both pig skin (in vitro) and rat skin (in vivo) are permeable to 5-amino-o-cresol, the latter being more permeable.

A 94% recovery of radioactivity (corrected for incomplete excretion from internal application) in human urine after oral administration of radioactive 4-amino-2-hydroxytoluene /was reported/.

CIR ingredient: 4-Amino-2-Hydroxytoluene

Used as a coupler in oxidative hair dyeing; [HSDB]

Dressing Hair [Category: Other]

Used almost exclusively in cosmetics as a coupler in oxidative hair dyeing.