2-Amino-5-nitrophenol

Olive-brown, brown to orange crystalline solid

Orange needles when recrystallized from water

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

Slightly soluble in water

Soluble in ethanol, acetone, and benzene

Soluble in deuterated DSMO

388 to 396 °F (decomposes) (NTP, 1992)

205.8 °C

2-amino-5-nitrophenol appears as brown amorphous granules or powder. Melting point 198-202 °C.

Olive-brown, brown, or orange solid; [HSDB] Green crystalline solid; [MSDSonline]

Warning

H315 (95%): Causes skin irritation [Warning Skin corrosion/irritation]

P203, P261, P264, P264+P265, P271, P273, P280, P302+P352, P304+P340, P305+P351+P338, P318, P319, P321, 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 2175 reports by companies from 15 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, 2-amino-5-nitro-

Status: Active Update: 03-08-2016 https://echa.europa.eu/registration-dossier/-/registered-dossier/12835

2-AMINO-5-NITROPHENOL is a mild reducing agent. Incompatible with strong oxidizing agents. Reacts slowly with oxygen in the air at room temperature. Stable at temperatures up to 140 °F for two weeks when kept in the dark and under nitrogen. Stable under nitrogen for up to 24 weeks 77 °F. Incompatible with strong bases (NTP, 1992). Incompatible with acid chlorides and acid anhydrides.

Skin Irrit. 2 (95%)

Skin sensitisation - category 1

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.

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 85(SRC), determined from a structure estimation method(2), indicates that 2-amino-5-nitrophenol is expected to have high mobility in soil(SRC). Volatilization of 2-amino-5-nitrophenol from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 7.8X10-13 atm-cu m/mole(SRC), using a fragment constant estimation method(3). 2-Amino-5-nitrophenol is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 3.5X10-5 mm Hg(SRC), determined from a fragment constant method(4). Biodegradation data were not available(SRC, 2007).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 85(SRC), determined from a structure estimation method(2), indicates that 2-amino-5-nitrophenol is expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is not expected(3) based upon an estimated Henry's Law constant of 7.8X10-13 atm-cu m/mole(SRC), developed using a fragment constant estimation method(4). According to a classification scheme(5), an estimated BCF of 3(SRC), from an estimated log Kow of 0.99(6) and a regression-derived equation(7), suggests the potential for bioconcentration in aquatic organisms is low(SRC). Hydrolysis is not expected to be an important environmental fate process since this compound lacks functional groups that hydrolyze under environmental conditions(3). Biodegradation data were not available(SRC, 2007).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 2-amino-5-nitrophenol, which has an estimated vapor pressure of 3.5X10-5 mm Hg at 25 °C(SRC), determined from a fragment constant method(2), will exist in both the vapor and particulate phases in the ambient atmosphere. Vapor-phase 2-amino-5-nitrophenol 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 41 hours(SRC), calculated from its rate constant of 9.4X10-12 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). Particulate-phase 2-amino-5-nitrophenol may be removed from the air by wet or dry deposition(SRC).

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=121-88-0]

Using a structure estimation method based on molecular connectivity indices(1), the Koc of 2-amino-5-nitrophenol can be estimated to be 85(SRC). According to a classification scheme(2), this estimated Koc value suggests that 2-amino-5-nitrophenol is expected to have high mobility in soil(SRC).

2-Amino-5-nitrophenol's production and use as an intermediate in the manufacture azo dyes, which are used for coloring synthetic resins, lacquers, inks and wood stains and its use as a dye in semi-permanent hair coloring products and limited use in permanent hair coloring products(1) may result in its release to the environment through various waste streams.

2-Amino-5-nitrophenol

Group 3: Not classifiable as to its carcinogenicity to humans

Volume 57: (1993) Occupational Exposures of Hairdressers and Barbers and Personal Use of Hair Colourants; Some Hair Dyes, Cosmetic Colourants, Industrial Dyestuffs and Aromatic Amines

1993

1992

2-Amino-5-Nitrophenol

An estimated BCF of 3 was calculated in fish for 2-amino-5-nitrophenol(SRC), using an estimated log Kow of 0.99(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).

The Henry's Law constant for 2-amino-5-nitrophenol is estimated as 7.8X10-13 atm-cu m/mole(SRC) using a fragment constant estimation method(1). This Henry's Law constant indicates that 2-amino-5-nitrophenol is expected to be essentially nonvolatile from water surfaces(2). 2-Amino-5-nitrophenol is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 3.5X10-5 mm Hg(SRC), determined from a fragment constant method(3).

/LABORATORY ANIMALS: Acute Exposure/ Male Charles River CD rats (10 per group) received intraperitoneally either 2-amino-4-nitrophenol, 2-amino-5-nitrophenol, or 4-amino-2-nitrophenol in a 10% aqueous DMSO solution. The LD50 for 2-amino-4-nitrophenol was reported to be 246 mg/kg, the LD50 for 2-amino-5-nitrophenol was reported to be greater than 800 mg/kg, and the LD50 for 4-amino-2-nitrophenol was reported to be 302 mg/kg.

/LABORATORY ANIMALS: Acute Exposure/ 2-Amino-4-nitrophenol, 2-amino-5-nitrophenol, and 4-amino-2-nitrophenol were orally administered to groups of five Charles River CD rats of each sex in an oil-in-water emulsion. The LD50 values for 2-amino-4-nitrophenol and 2-amino-5-nitrophenol were greater than 4000 mg/kg and the LD50 for 4-amino-2-nitrophenol was calculated to be 33 mg/kg.

/LABORATORY ANIMALS: Acute Exposure/ ... This study tested 33 dyes in guinea pigs using a modified Buehler and Klecak method for open epicutaneous testing. The dyes were tested at an induction concentration of 10% and challenge concentrations of 10.0%, 5.0%, and 2.5%. Nine of the 33 dyes tested /including 2-amino-5-nitrophenol/ produced positive allergic reactions in the guinea pig model ... . When eight of the nine positive dyes were retested using a 1% induction concentration, five dyes /including 2-amino-5-nitrophenol/ produced allergic contact dermatitis at a 1% challenge concentration ... , two at a 0.5% challenge concentration ( /including/ 2-amino-5-nitrophenol ... ), and one at a 0.25% challenge concentration (2-amino-5-nitrophenol). DNCB at a 0.5% induction/challenge concentration was used as a positive control. ...

/LABORATORY ANIMALS: Subchronic or Prechronic Exposure/ ... Sixty B6C3F-1 mice were divided into six groups containing five mice/sex/group. The mice received either twelve doses of 2-amino-5-nitrophenol or corn oil (control material) at one of the following doses: 0, 313, 625, 1250, 2500, or 5000 mg/kg over a 16-day period. Clinical observations were performed twice daily, body weights were recorded weekly, and animals were necropsied. Nineteen mice died prior to the end of the study. Two males and five females died in the 5000 mg/kg group, three males and three females died in the 2500 mg/kg group, one female died in the 625 mg/kg group and two vehicle control males died. No significant difference in body weights occurred between treated and control animals and clinical observations were limited to loose stools in the males in the 5000 mg/kg group and two males were prostrate for the first week of the study in the 2500 mg/kg group. The LD50 in mice was greater than 1250 mg/kg but less than 2500 mg/kg.

For more Non-Human Toxicity Excerpts (Complete) data for 2-AMINO-5-NITROPHENOL (14 total), please visit the HSDB record page.

Evaluation: There is inadequate evidence in humans for the carcinogenicity of 2-amino-5-nitrophenol. There is limited evidence in experimental animals for the carcinogenicity of 2-amino-5-nitrophenol. Overall evaluation: 2-Amino-5-nitrophenol is not classifiable as to its carcinogenicity to humans (Group 3).

The principal rat liver microsomal metabolite of 4-nitroaniline was isolated by high pressure liquid chromatography and was characterized as 2-amino-5-nitrophenol (2-hydroxy-4-nitroaniline) by comparison of its mass, nuclear magnetic resonance, and ultraviolet spectra and HPLC retention time to the synthetic compound. ... Pretreatment of rats with phenobarbital and 3-methylcholanthrene increased the rate of conversion of 4-nitroaniline to 2-hydroxy-4-nitroaniline by 2-fold and 4-fold, respectively; the reaction required NADPH and was inhibited by heat treatment of microsomes, by argon and carbon monoxide:oxygen atmospheres and by the cytochrome P-450 inhibitor, 2-[(2,4-dichloro-6-phenyl)phenoxy]ethylamine. ...

CIR ingredient: 2-Amino-5-Nitrophenol

Used in hair dyes and to make azo dyes; [HSDB]

Dressing Hair [Category: Other]

2-Amino-5-nitrophenol is used as an intermediate in the manufacture of several azo dyes, including CI Solvent Red 8, which is used for coloring synthetic resins, lacquers, inks and wood stains. It is also used as a dye in semi-permanent hair coloring products to produce red and gold-blond shades. It is used to a limited extent in permanent hair coloring products.

(1977) 2.33X10+7 GRAMS (PRINCPL CUSTMS DISTS)

(1979) 5.95X10+6 GRAMS (PRINCPL CUSTMS DISTS)

(1977) NOT PRODUCED COMMERCIALLY IN US

(1979) NOT PRODUCED COMMERCIALLY IN US

Production volumes for non-confidential chemicals reported under the Inventory Update Rule. [Table#4847]

NITRATION OF O-ACETAMIDOPHENOL OR 2-METHYLBENZOXAZOLE IN SULFURIC ACID FOLLOWED BY HYDROLYSIS OF THE SEPARATED ISOMERS WITH SODIUM HYDROXIDE

2-Amino-5-nitrophenol is produced from 2-aminophenol by reaction with acetic anhydride to form 2-methylbenzoxazole, which is nitrated and hydrolysed to form 2-amino-5-nitrophenol.

2-Amino-5-nitrophenol is prepared from 3-nitro-4-hyroxybenzenesulfonamide using sodium hyposulfite and caustic or zinc and HCl as the reducing agents. It may also be obtained from 2-amino-1-phenol-4-sulfonic acid by treatment with carbon disulfide to give a substituted benzoxazole whose ring is opened to the desired sulfonamide. It may be prepared by the chlorosulfonation of 2-chloronitrobenzene followed by aminolysis and hydrolysis.

Production is by nitration of benzoxazolone and separation from the 2-amino-4-nitro-phenol isomer after treatment with hydrochloric acid.

Phenol, 2-amino-5-nitro-: ACTIVE

2-Amino-5-nitrophenol is not produced in commercial quantities in the USA. It is available in research quantities, at purities ranging from 90-99% from Jos. H. Lowenstein & Sons, 1991; TCI America, 1991; Aldrich Chemical Co., 1992; Fluka Chemie AG, 1993.