Hydroxylamine

-1.5

1.227 at 68 °F (USCG, 1999) - Denser than water; will sink

1.227

1.2 g/cm³

Relative density of the vapour/air-mixture at 20 °C (air = 1): 1.00

Density (at 20 °C): 1.12 g/cm³

1.227 @25 °C

Colorless cyrstals

Large white flakes or white needles

Very sol in water, liq ammonia, methanol; sparingly sol in ether, benzene, carbon disulfide, chloroform

Soluble in alcohol, acids, and cold water

Solubility in water at 20 °C: freely soluble

265 °F (USCG, 1999)

[ICSC] 265 °F

explodes at 129 °C

133.7 °F 22 mm 158 °F 60 mm (USCG, 1999)

70 °C at 60 mm Hg

107 °C

58 °C @760 [mm Hg]

When heated to decomposition it emits toxic fumes of NOx /nitrogen oxides/.

Decomposes rapidly at room temp. ... Decomposes in hot water.

91.49 °F (USCG, 1999)

33 °C

33 °C

33 °C

8 °C

34 °C

Relative vapor density (air = 1): 1.1

9.75 [mmHg]

53 mm Hg at 32 °C

Vapor pressure, kPa at 47 °C: 1.3

Vapor pressure, kPa at 20 °C: 1.4

53 [mm Hg] @32 °C

Hydroxylamine is an odorless white crystalline solid. Sinks and mixes with water. (USCG, 1999)

Liquid

Highly hygroscopic white solid; Unstable; Quickly decomposed at room temperature (especially by atmospheric moisture and carbon dioxide); mp = 33 deg C; [Merck Index]

Solid

VERY HYGROSCOPIC WHITE NEEDLES OR FLAKES.

COLOURLESS SOLUTION IN WATER.

UNSTABLE; RAPID DECOMP AT ROOM TEMP IN PRESENCE OF ATMOSPHERIC MOISTURE & CO2

SLOWLY DECOMPOSED WHEN MOIST /HYDROXYLAMINE HYDROCHLORIDE/

Danger

H200: (Deleted) Unstable Explosive [Danger Explosives]；H290: May be corrosive to metals [Warning Corrosive to Metals]；H302: Harmful if swallowed [Warning Acute toxicity, oral]；H312: Harmful in contact with skin [Warning Acute toxicity, dermal]；H315: Causes skin irritation [Warning Skin corrosion/irritation]；H317: May cause an allergic skin reaction [Warning Sensitization, Skin]；H318: Causes serious eye damage [Danger Serious eye damage/eye irritation]；H335: May cause respiratory irritation [Warning Specific target organ toxicity, single exposure; Respiratory tract irritation]；H351: Suspected of causing cancer [Warning Carcinogenicity]；H373 **: May causes damage to organs through prolonged or repeated exposure [Warning Specific target organ toxicity, repeated exposure]；H400: Very toxic to aquatic life [Warning Hazardous to the aquatic environment, acute hazard]

P201, P202, P203, P234, P260, P261, P264, P264+P265, P270, P271, P272, P273, P280, P281, P301+P317, P302+P352, P304+P340, P305+P354+P338, P317, P318, P319, P321, P330, P332+P317, P333+P317, P362+P364, P372, P373, P380, P390, P391, P401, P403+P233, P405, P406, and P501 (click each P-code to see the statement)

Danger

Chemical: Hydroxylamine

Hydroxylamine is listed on the EPA's Chemical Data Reporting (CDR) system. Manufacturers and importers of Hydroxylamine are required to report information about their production and use of this chemical to the EPA under the Toxic Substances Control Act (TSCA). (40 eCFR Part 711)

Status: Active Update: 02-06-2016 https://echa.europa.eu/registration-dossier/-/registered-dossier/16246

Hydroxylamine: Does not have an individual approval but may be used under an appropriate group standard

The New Jersey Worker and Community Right to Know Act requires public and private employers to provide information about hazardous substances at their workplaces. (N.J.S.A. 34:5A-1 et. seq.)

IMAP assessments - Hydroxylamine and its salts: Human health tier II assessment

Corrosive

Special Hazards of Combustion Products: Nitrogen oxides - toxic fumes - react with water or steam to produce heat and corrosive liquids - can react violently with reducing materials.；Behavior in Fire: May explode when exposed to heat or flame. Explodes at 265 °F. (USCG, 1999)

Gives off irritating or toxic fumes (or gases) in a fire. Risk of explosion on heating. Risk of fire and explosion on contact with many substances. See Chemical Dangers.

Combustible. Gives off irritating or toxic fumes (or gases) in a fire. Risk of explosion on heating.

Dangerous fire hazard when exposed to heat, flame, and oxidizers. May ignite spontaneously in air if a large surface area is exposed (e.g. precipitate on paper).

Ignites on contact with copper(II)sulfate; metals (e.g. sodium); oxidants (e.g. barium peroxide; barium oxide; lead dioxide/ potassium permanganate; chlorine); phosphorus chlorides (e.g. phosphorus trichloride; phosphorus pentachloride).

INHALATION: Moderately toxic by inhalation and oral routes with the following symptoms possible: headache, vertigo, tinnitus, dyspnea, nausea and vomiting, cyanosis, proteinuria and hematuria, jaundice, restlessness, and convulsion. Methemoglobinemia has been reported. EYES: Corrosive - highly irritating. SKIN: Irritating or corrosive to skin. INGESTION: Moderately toxic by inhalation and oral routes with the following symptoms possible; headache, vertigo, tinnitus, dyspnea, nausea and vomiting, cyanosis, proteinuria and hematuria, jaundice, restlessness, and convulsion. Methemoglobinemia has been reported. (USCG, 1999)

Crystals cause first degree burns on short exposure. [CHRIS] Reported toxic effects in humans include methemoglobinemia and skin sensitization. [HSDB] Allergic contact dermatitis reported in workers developing color photographs and handling laboratory reagents; [Kanerva, p. 1803] A skin and respiratory tract irritant; Corrosive to eyes; Can induce methemoglobinemia and consequent anemia; May cause skin sensitization; [ICSC] Occupational asthma confirmed in 2 workers exposed in paper recycling (de-inking process); [Malo] Reacts with water forming corrosive liquids; Rapidly decomposed at room temperature and by hot water; A strong reducing agent; Highly irritating or corrosive to skin and eyes; Reports of methemoglobinemia; [CAMEO] An irritant; May cause skin sensitization; Harmful by ingestion; High doses may cause methemoglobinemia; [Aldrich MSDS]

Bases, Strong；Reducing Agents, Strong

H200; H290; H302; H312; H315; H318; H317; H335; H351; H373; H400

H290; H302; H312; H315; H318; H317; H335; H351; H373; H400

UN Hazard Class: 8; UN Pack Group: III

A REVIEW WITH 304 REFERENCES ON CHEMICAL MECHANISMS INVOLVED IN MUTAGENESIS INDUCED BY HYDROXYLAMINE & ITS DERIVATIVES.[MARFEY P ET AL; GENETIC TOXICOLOGY OF HYDROXYLAMINES; MUTAT RES 86(2) 155 (1981)]

Explosive；Water-Reactive

Fire Extinguishing Agents: Use extreme caution - material may explode. Use remote extinguishing equipment or unmanned fixed turret and hose nozzles - evacuate area. (USCG, 1999)

Use water in large amounts, alcohol-resistant foam, powder. In case of fire: keep drums, etc., cool by spraying with water. Combat fire from a sheltered position.

Use water, alcohol-resistant foam, powder. In case of fire: keep drums, etc., cool by spraying with water. Combat fire from a sheltered position.

Fresh air, rest. Administration of oxygen may be needed. Refer immediately for medical attention.

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

Rinse with plenty of water for several minutes (remove contact lenses if easily possible). Refer immediately for medical attention.

Rinse mouth. Administration of oxygen may be needed. Refer immediately for medical attention.

Fresh air, rest. Administration of oxygen may be needed. Refer immediately for medical attention.

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

Call a physician.；EYES: Flush with water.；SKIN: Wash with soap and water immediately.；INGESTION: Remove by gastric lavage or emesis (vomiting) and catharsis. (USCG, 1999)

Fireproof. Separated from incompatible materials. See Chemical Dangers. Cool. Dry. Well closed. Store in an area without drain or sewer access. Provision to contain effluent from fire extinguishing.

Fireproof. Separated from incompatible materials. See Chemical Dangers. Cool. Well closed. Do not allow to dry out. Store in an area without drain or sewer access. Provision to contain effluent from fire extinguishing.

Closed containers may rupture violently when heated.

Not combustible. Extinguish fire using agent suitable for surrounding fire. Fight fire from protected location or maximum possible distance. Approach fire from upwind to avoid hazardous vapors and toxic decomposition products. Explosive decomposition may occur under fire conditions.

Separate from oxidizing materials. store in a cool, dry, well-ventilated location. store away from heat, oxidizers, and sunlight. Outside or detached storage is preferred.

Neutralizing Agents for Acids and Caustics: Sodium bisulfate (USCG, 1999)

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

Personal protection: particulate filter respirator adapted to the airborne concentration of the substance. Do NOT let this chemical enter the environment. Sweep spilled substance into covered non-metallic containers. If appropriate, moisten first to prevent dusting. Carefully collect remainder. Then store and dispose of according to local regulations.

Personal protection: filter respirator for inorganic gases and vapours adapted to the airborne concentration of the substance. Do NOT let this chemical enter the environment. Collect leaking and spilled liquid in covered non-metallic containers as far as possible. Absorb remaining liquid in inert absorbent. Then store and dispose of according to local regulations.

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.

MATERIAL SHOULD BE HANDLED WITH CAUTION TO AVOID CONTACT & COMPLETE ELIMINATION OF MANUAL PROCESSES BY MECHANIZATION IS RECOMMENDED.

Excerpt from ERG Guide 153 [Substances - Toxic and/or Corrosive (Combustible)]:；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)

ARGININE...PROTECTS ANIMALS AGAINST DEATH BY HYDROXYLAMINE EVEN THOUGH THE METHEMOGLOBINEMIC RESPONSE IS UNCHANGED.

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 14(SRC), determined from a structure estimation method(2), indicates that hydroxylamine is expected to have very high mobility in soil(SRC). The pKa of hydroxylamine is 5.94(3) which indicates this compound will partially exist as a cation under acidic conditions, and cations have lower mobility in soil than neutral species(SRC). Volatilization of hydroxylamine from moist soil surfaces is not expected to be an important fate process since cations do not volatilize(SRC) and the neutral species has an estimated Henry's Law constant of 6.9X10-9 atm-cu m/mole(SRC), using a fragment constant estimation method(4). The potential for volatilization of hydroxylamine from dry soil surfaces may exist(SRC) based upon a vapor pressure of 53 mm Hg(5) at 32 °C.

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 14(SRC), determined from a structure estimation method(2), indicates that hydroxylamine is not expected to adsorb to suspended solids and sediment(SRC). A pKa of 5.94(3) indicates hydroxylamine will partially exist as a cation in waters. Volatilization from water surfaces is not expected to be an important environmental fate process(SRC) since cations do not volatilize and the Henry's Law constant of the neutral species is 6.9X10-9 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 1.2(6,SRC) and a regression-derived equation(7), suggests the potential for bioconcentration in aquatic organisms is low(SRC).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), hydroxylamine, which has a vapor pressure of 53 mm Hg at 32 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase hydroxylamine 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 18 hours(SRC), calculated from its rate constant of 2.1X10-11 cu cm/molecule-sec at 25 °C(SRC) determined using a structure estimation method(3).

Methemoglobinemia - The presence of increased methemoglobin in the blood; the compound is classified as secondary toxic effect；Dermatotoxin - Skin burns.；Skin Sensitizer - An agent that can induce an allergic reaction in the skin.；Asthma - Reversible bronchoconstriction (narrowing of bronchioles) initiated by the inhalation of irritating or allergenic agents.；Toxic Pneumonitis - Inflammation of the lungs induced by inhalation of metal fumes or toxic gases and vapors.

The substance can be absorbed into the body by inhalation, through the skin and by ingestion.

The substance can be absorbed into the body by inhalation, through the skin and by ingestion.

Cough. Sore throat. Dizziness. Headache. Blue lips, fingernails and skin. Shortness of breath. Weakness.

MAY BE ABSORBED! Redness. Pain. Further see Inhalation.

Redness. Pain. Severe burns.

Nausea. Vomiting. Symptoms may be delayed. Further see Inhalation.

Cough. Sore throat. Dizziness. Headache. Blue lips, fingernails and skin. Shortness of breath. Weakness.

MAY BE ABSORBED! Redness. Pain. Further see Inhalation.

The substance is very toxic to aquatic organisms.

The substance is very toxic to aquatic organisms.

DURING PRE-EMPLOYMENT MEDICAL EXAM, WORKERS SHOULD BE SUBJECTED TO SKIN SENSITIVITY TESTS...DURING PERIODIC MEDICAL EXAM, PERSONS FOUND...SUFFERING FROM PERSISTENT SKIN DISEASE SHOULD BE REMOVED FROM EXPOSURE.

Using a structure estimation method based on molecular connectivity indices(1), the Koc for hydroxylamine can be estimated to be 14(SRC). According to a classification scheme(2), this estimated Koc value suggests that hydroxylamine is expected to have very high mobility in soil. A pKa of 5.94(3) indicates that hydroxylamine will partially exist in the protonated form in moist soils(SRC) and cations adsorb to soil stronger than neutral compounds.

HYDROXYLAMINE & ITS SALTS ARE CORROSIVE TO SKIN & HIGHLY IRRITANT TO EYES & MUCOUS MEMBRANES. REPEATED EXPOSURE MAY ENHANCE ALLERGIC REACTION PARTICULARLY OF...HANDS & FOREARMS FROM 1-2 WK TO 2-5 YEARS AFTER COMMENCEMENT OF EXPOSURE & CASES OF ECZEMA...OBSERVED FOLLOWING PROLONGED CONTACT.

CORROSIVE TO SKIN. ... MAY CAUSE METHEMOGLOBINEMIA.

SOLN HAS CORROSIVE ACTION ON SKIN. /HYDROXYLAMINE SULFATE/

...IN WORKERS. ...INCREASES OF METHEMOGLOBIN CONTENT OF BLOOD BY UP TO 25% HAVE BEEN REPORTED AT THE END OF THE WORKING DAY.

For more Human Toxicity Excerpts (Complete) data for HYDROXYLAMINE (6 total), please visit the HSDB record page.

Hydroxylamine's production and use as a reducing agent(1,2) and as an intermediate in the production of caprolactam(3) may result in its release to the environment through various waste streams(SRC).

An estimated BCF of 3 was calculated for hydroxylamine(SRC), using an estimated log Kow of -1.2(1,SRC) 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 pKa for hydroxylamine is 5.94(1), which indicates this compound will partially exist in the protonated form(SRC). Volatilization from moist soils and water surfaces is not expected since cations don't volatilize and the estimated Henry's Law constant for the neutral species is 6.9X10-9 atm-cu m/mole(SRC), using a fragment constant estimation method(2). The potential for volatilization of hydroxylamine from dry soil surfaces may exist(SRC) based upon a vapor pressure of 53 mm Hg(3).

Chemical: Hydroxylamine

Hydroxylamine is listed on the EPA's Chemical Data Reporting (CDR) system. Manufacturers and importers of Hydroxylamine are required to report information about their production and use of this chemical to the EPA under the Toxic Substances Control Act (TSCA). (40 eCFR Part 711)

Status: Active Update: 02-06-2016 https://echa.europa.eu/registration-dossier/-/registered-dossier/16246

Hydroxylamine: Does not have an individual approval but may be used under an appropriate group standard

The New Jersey Worker and Community Right to Know Act requires public and private employers to provide information about hazardous substances at their workplaces. (N.J.S.A. 34:5A-1 et. seq.)

Epidermis；Fibroblasts；Kidney；Liver；Spleen

Cytoplasm

Used as a reducing agent, antioxidant, chemical intermediate, and termination agent in polymers; used in the photography, chemistry, textile, leather, paint, soap, rubber, and plastics industries; [HSDB] Hydroxylamine sulfate used in photography (color neutralizing bath); [www.ci.tucson.az.us/arthazards/medium.html]

Plastic Composites Manufacturing [Category: Industry]；Leather Tanning and Processing [Category: Industry]；Photographic Processing [Category: Other]；Textiles (Printing, Dyeing, or Finishing) [Category: Industry]

As reducing agent in photography; in synthetic and analytical chemistry; to purify aldehydes and ketones; as antioxidant for fatty acids and soaps; as dehairing agent for hides

Over 95% of hydroxylamine produced is used for the production of cyclohexanone oxime or caprolactam.

CHEMICAL INTERMEDIATE FOR MISCELLANEOUS ORGANIC & INORGANIC CHEMICALS (IN LAB); REDUCING AGENT; CHEMICAL INTERMEDIATE (CAPTIVELY) FOR CAPROLACTAM USED IN NYLON 6; ABSORBENT FOR REMOVING NITROGEN DIOXIDE; TERMINATION AGENT IN PEROXIDE-CATALYZED POLYMERIZATIONS; AGENT IN DEVELOPERS FOR PHOTOGRAPHIC SILVER EMULSIONS

2023: 1,000,000 - <5,000,000 lb；2022: 1,000,000 - <5,000,000 lb；2021: 1,000,000 - <5,000,000 lb；2020: 1,000,000 - <5,000,000 lb

Reducing agent

Hurd, Inorg Syn 1: 87 (1939); Benson et al, J Am Chem Soc 78: 4202 (1956).

Semon, Org Syn 3: 61 (1923); Benson et al; J Am Chem Soc 78: 4202 (1956) /Hydroxylamine hydrochloride/

All Other Chemical Product and Preparation Manufacturing

Hydroxylamine: ACTIVE

World production capacity of hydroxylamine is 800,000 tons annually.