Cyclohexylisocyanat

Toxic Gases & Vapors -> Monoisocyanates

Flammable agents - 2nd degree

0.98 (NTP, 1992) - Less dense than water; will float

0.98 g/cu cm at 25 °C

Relative density (water = 1): 0.98

Reacts with water (decomposes) (NTP, 1992)

Solubility in water: reaction

120 °F (NTP, 1992)

120 °F

48 °C (closed cup)

48 °C c.c.

334 to 338 °F at 760 mmHg (NTP, 1992)

172 °C

168 °C

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

Decomposes on burning. This produces toxic fumes of hydrogen cyanide and nitrogen oxides.

2 mmHg at 77.4 °F (NTP, 1992)

1.02 [mmHg]

1.02 mm Hg at 25 °C

Danger

H226 (100%): Flammable liquid and vapor [Warning Flammable liquids]

P210, P233, P240, P241, P242, P243, P260, P261, P264, P264+P265, P270, P271, P272, P280, P284, P301+P317, P301+P330+P331, P302+P352, P302+P361+P354, P303+P361+P353, P304+P340, P305+P351+P338, P305+P354+P338, P316, P317, P319, P320, P321, P330, P332+P317, P333+P317, P337+P317, P342+P316, P362+P364, P363, P370+P378, P403, P403+P233, P403+P235, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 97 reports by companies from 13 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Status: Active Update: 27-03-2023 https://echa.europa.eu/registration-dossier/-/registered-dossier/34734

Cyclohexyl isocyanate: HSNO Approval: HSR004417 Approved with controls

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.)

Excerpt from ERG Guide 155 [Substances - Toxic and/or Corrosive (Flammable / Water-Sensitive)]:

· HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames.

Flammable. Gives off irritating or toxic fumes (or gases) in a fire. Above 48 °C explosive vapour/air mixtures may be formed.

Excerpt from ERG Guide 155 [Substances - Toxic and/or Corrosive (Flammable / Water-Sensitive)]:

· TOXIC and/or CORROSIVE; inhalation, ingestion or contact (skin, eyes) with vapors, dusts or substance may cause severe injury, burns or death.

Corrosive to skin; [Quick CPC] A skin, eye, and respiratory tract irritant; Lachrymator; May cause skin sensitization and asthma after prolonged contact; [ICSC] A lachrymator; Can cause bronchitis, asthma, and life-threatening chemical pneumonitis; [CHEMINFO]

Section 8(a) of TSCA requires manufacturers of this chemical substance to report preliminary assessment information concerned with production, exposure, and use to EPA as cited in the preamble in 51 FR 41329. Effective date: 10/29/90; Reporting date: 12/27/90.

Pursuant to section 8(d) of TSCA, EPA promulgated a model Health and Safety Data Reporting Rule. The section 8(d) model rule requires manufacturers, importers, and processors of listed chemical substances and mixtures to submit to EPA copies and lists of unpublished health and safety studies. Cyclohexane, isocyanato- is included on this list. Effective date: 10/29/90; Sunset date: 11/9/93.

Isocyanates and thioisocyanates are incompatible with many classes of compounds, reacting exothermically to release toxic gases. Reactions with amines, aldehydes, alcohols, alkali metals, ketones, mercaptans, strong oxidizers, hydrides, phenols, and peroxides can cause vigorous releases of heat. Acids and bases initiate polymerization reactions in these materials. Some isocyanates react with water to form amines and liberate carbon dioxide. Base-catalysed reactions of isocyanates with alcohols should be carried out in inert solvents. Such reactions in the absence of solvents often occur with explosive violence [Wischmeyer 1969].

Excerpt from ERG Guide 155 [Substances - Toxic and/or Corrosive (Flammable / Water-Sensitive)]:

Use foam, alcohol-resistant foam, powder, carbon dioxide, dry sand. In case of fire: keep drums, etc., cool by spraying with water. NO direct contact with water. Combat fire from a sheltered position.

Fresh air, rest. Artificial respiration may be needed. Refer for medical attention.

Remove contaminated clothes. Rinse skin with plenty of water or shower. Refer for medical attention . Wear protective gloves when administering first aid.

First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.

Give a slurry of activated charcoal in water to drink. Do NOT induce vomiting. Refer for medical attention .

· CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper not available or no answer, refer to appropriate telephone number listed on the inside back cover.

· ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area.

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.

General First Aid:

· Wear positive pressure self-contained breathing apparatus (SCBA).

TIH (Toxic Inhalation Hazard) - Term used to describe gases and volatile liquids that are toxic when inhaled. Some are TIH materials themselves, e.g., chlorine, and some release TIH gases when spilled in water, e.g., chlorosilanes. [ERG 2016].

If material on fire or involved in fire: Do not extinguish fire unless flow can be stopped. Use water in flooding quantities as fog. Solid streams of water may be ineffective. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. Use "alcohol" foam, dry chemical or carbon dioxide. Keep run-off water out of sewers and water sources.

Evacuation: If fire becomes uncontrollable or container is exposed to direct flame, consider evacuation of one-third (1/3) mile radius.

Use foam, alcohol-resistant foam, powder, carbon dioxide, dry sand.

No direct contact with water. Combat fire from a sheltered position.

Consult an expert! Ventilation. Collect leaking and spilled liquid in sealable containers as far as possible. Absorb remaining liquid in sand or inert absorbent. Then store and dispose of according to local regulations. Do not wash away into sewer. Personal protection: complete protective clothing including self-contained breathing apparatus.

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity 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 and plant life; and conformance with environmental and public health regulations.

Consult an expert! Ventilation. Collect leaking and spilled liquid in sealable containers as far as possible. Absorb remaining liquid in sand or inert absorbent. Then store and dispose of according to local regulations. Do NOT wash away into sewer. Personal protection: complete protective clothing including self-contained breathing apparatus.

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 800(SRC), determined from a structure estimation method(2), indicates that cyclohexylisocyanate is expected to have low mobility in soil(SRC). Volatilization of cyclohexylisocyanate from moist soil surfaces is expected to be an important fate process(SRC) given an estimated Henry's Law constant of 1.7X10-3 atm-cu m/mole(SRC), using a fragment constant estimation method(3). Cyclohexylisocyanate is expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 1.02 mm Hg at 25 °C(4). Biodegradation data in soil were not available(SRC, 2012).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 800(SRC), determined from a structure estimation method(2), indicates that cyclohexylisocyanate is expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(3) based upon an estimated Henry's Law constant of 1.7X10-3 atm-cu m/mole(SRC), developed using a fragment constant estimation method(4). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 4 hours and 5 days, respectively(SRC). According to a classification scheme(5), an estimated BCF of 50(SRC), from an estimated log Kow of 3.06(6) and a regression-derived equation(7), suggests the potential for bioconcentration in aquatic organisms is moderate(SRC). Isocyanates hydrolyze readily in water to yield a carbamic acid; therefore, hydrolysis of cyclohexylisocyanate is expected to be an important environmental fate process(8). However, the rapid hydrolysis of cyclohexylisocyanated precludes adsorption to solids and sediment, volatilization and bioconcentration(SRC). Biodegradation data in water were not available(SRC, 2012).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), cyclohexylisocyanate, which has a vapor pressure of 1.02 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase cyclohexylisocyanate 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 13 hours(SRC), calculated from its rate constant of 1.0X10-11 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). Cyclohexylisocyanate does not contain chromophores that absorb at wavelengths >290 nm(4), and therefore is not expected to be susceptible to direct photolysis by sunlight(SRC).

Burning sensation. Cough. Headache. Laboured breathing. Shortness of breath. Sore throat. Symptoms may be delayed.

Redness.

Watering of the eyes. Redness. Pain. Blurred vision. Severe deep burns.

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.[Available from, as of June 21, 2012: http://ntp-apps.niehs.nih.gov/ntp_tox/index.cfm?fuseaction=ntpsearch.searchresults&searchterm=3173-53-3]

Cyclohexylisocyanate was detected at concentrations of 169 and 547 ug/L in 2 leachate samples from a landfill in Lombardy, Italy which receives industrial waste from sources that include metallurgy and sludge. The limit of detection was 17.14 ng/L(1).

Using a structure estimation method based on molecular connectivity indices(1), the Koc of cyclohexylisocyanate can be estimated to be 800(SRC). According to a classification scheme(2), this estimated Koc value suggests that cyclohexylisocyanate is expected to have low mobility in soil.

/SIGNS AND SYMPTOMS/ A worker suspected of having isocyanate-induced asthma/sensitization will exhibit the traditional symptoms of acute airway obstruction, e.g., coughing, wheezing, shortness of breath, tightness in the chest, and nocturnal awakening. An isocyanate-exposed worker may first develop an asthmatic condition (i.e., become sensitized) after a single (acute) exposure, but sensitization usually takes a few months to several years of exposure. The asthmatic reaction may occur minutes after exposure (immediate), several hours after exposure (late), or a combination of both immediate and late components after exposure (dual). The late asthmatic reaction is the most common, occurring in approximately 40% of isocyanate sensitized workers. After sensitization, any exposure, even to levels below an occupational exposure limit or standard, can produce an asthmatic response that may be life threatening. Experience with isocyanates has shown that monomeric, prepolymeric and polyisocyanate species are capable of producing respiratory sensitization in exposed workers. /Isocyanates/

/SIGNS AND SYMPTOMS/ Exposure to isocyanates is irritating to the skin, mucous membranes, eyes, and respiratory tract. The most common adverse health outcome associated with isocyanate exposure is asthma due to sensitization; less prevalent are contact dermatitis (both irritant and allergic forms) and hypersensitivity pneumonitis (HP). Contact dermatitis can result in symptoms such as rash, itching, hives, and swelling of the extremities. /Isocyanates/

/SIGNS AND SYMPTOMS/ The initial symptoms associated with isocyanate-induced hypersensitivity pneumonitis (HP) are flu-like, including shortness of breath, nonproductive cough, fever, chills, sweats, malaise, and nausea. After the onset of HP, prolonged and/or repeated exposures may lead to an irreversible decline in pulmonary function and lung compliance and to the development of diffuse interstitial fibrosis. Early diagnosis is difficult since many aspects of HP, i.e., the flu-like symptoms and the changes in pulmonary function, are manifestations common to many other respiratory diseases and conditions. /Isocyanates/

An estimated BCF of 50 was calculated in fish for cyclohexylisocyanate(SRC), using an estimated log Kow of 3.06(1) and a regression-derived equation(2). According to a classification scheme(3), this BCF suggests the potential for bioconcentration in aquatic organisms is moderate(SRC). However, the rapid hydrolysis of cyclohexylisocyanated precludes bioconcentration(SRC).

The Henry's Law constant for cyclohexylisocyanate is estimated as 1.7X10-3 atm-cu m/mole(SRC) using a fragment constant estimation method(1). This Henry's Law constant indicates that cyclohexylisocyanate is expected to volatilize from water surfaces(2). Based on this Henry's Law constant, the volatilization half-life from a model river (1 m deep, flowing 1 m/sec, wind velocity of 3 m/sec)(2) is estimated as 4 hours(SRC). The volatilization half-life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec)(2) is estimated as 5 days(SRC). Cyclohexylisocyanate's Henry's Law constant indicates that volatilization from moist soil surfaces may occur(SRC). Cyclohexylisocyanate is expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 1.02 mm Hg(3). However, the rapid hydrolysis of cyclohexylisocyanated precludes volatilization(SRC).

Section 8(a) of TSCA requires manufacturers of this chemical substance to report preliminary assessment information concerned with production, exposure, and use to EPA as cited in the preamble in 51 FR 41329. Effective date: 10/29/90; Reporting date: 12/27/90.

Pursuant to section 8(d) of TSCA, EPA promulgated a model Health and Safety Data Reporting Rule. The section 8(d) model rule requires manufacturers, importers, and processors of listed chemical substances and mixtures to submit to EPA copies and lists of unpublished health and safety studies. Cyclohexane, isocyanato- is included on this list. Effective date: 10/29/90; Sunset date: 11/9/93.

... Preincubation of BCNU, CCNU, and methyl-CCNU with calmodulin produced a concentration-dependent inhibition of in vitro calmodulin activity expressed as stimulation of cyclic nucleotide phosphodiesterase. Cyclohexylisocyanate produced a similar inhibition. ...

Used to make pharmaceuticals and agricultural chemicals; [CAMEO]

To form cyclohexyl carbamates or ureas for agricultural chemicals or pharmaceutical use.

Cyclohexane, isocyanato- is listed as a High Production Volume (HPV) chemical (65FR81686). Chemicals listed as HPV were produced in or imported into the U.S. in >1 million pounds in 1990 and/or 1994. The HPV list is based on the 1990 Inventory Update Rule. (IUR) (40 CFR part 710 subpart B; 51FR21438).

Production volumes for non-confidential chemicals reported under the Inventory Update Rule.[Table#7986]