2,4-D이소시아나토-1-메틸벤젠, 호모플로이머

Hazardous Air Pollutants (HAPs)

Carcinogens

Industrial compound

Plastics & Rubber -> Diisocyanates

Plastics & Rubber -> Diisocyanates

Plastics & Rubber -> Diisocyanates

1.22 at 77 °F (NTP, 1992) - Denser than water; will sink

1.2244 at 68 °F (EPA, 1998) - Denser than water; will sink

1.2244 at 20 °C/4 °C

Saturated liquid density: 75.879 lb/cu ft; liquid heat capacity: 0.398 Btu/lb-F; liquid thermal conductivity: 1.179 Btu-inch/hr-sq ft-F; liquid viscosity: 3.769 Centipoise (all at 85 °F)

Saturated vapor pressure: 0.004 lb/sq in; saturated vapor density: 0.00011 lb/cu ft (all at 130 °F)

1.22 g/mL at 25 °C

Water-white to pale yellow liquid

Clear faintly yellow liquid

Colorless to pale yellow, solid or liquid (above 71 °F)

Liquid at room temperature ... Darkens on exposure to sunlight

Clear colorless to pale yellow liquid; pungent odor

Reacts with water (NTP, 1992)

Decomposes (NTP, 1992)

Very soluble in acetone, benzene, ethyl ether

Soluble in ether. acetone, and other organic solvents

Miscible with alcohol (decomposition). Miscible with ether, acetone, benzene, carbon tetrachloride, chlorobenzene, diglycol monomethyl ether, kerosene, olive oil

Solubility in water: reaction

250 °F (NTP, 1992)

270 °F (EPA, 1998)

127 °C

260 °F (127 °C)

270 °F CLOSED CUP /80% 2,4:20% 2,6/

127 °C c.c.

484 °F at 760 mmHg (NTP, 1992)

484 °F at 760 mmHg (EPA, 1998)

251 °C

BP: 126 °C at 11 mm Hg. Reacts with water with evolution of carbon dioxide.

Specific gravity: 1.22 at 25 °C; BP: 250 °C; FP: 11.3-13.5 °C /80% 2,4:20% 2,6/

125 °C; density: 1.22 g/mL at 25 °C /Toluene diisocyanate/

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

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

67.1 to 70.7 °F (NTP, 1992)

67.1 to 70.7 °F (EPA, 1998)

20.5 °C

MP: 11-14 °C (freezing point)

22 °C

67.1-70.7 °F

Danger

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

P203, P233, P260, P261, P264, P264+P265, P271, P272, P273, P280, P284, P302+P352, P304+P340, P305+P351+P338, P316, P318, P319, P320, P321, P332+P317, P333+P317, P337+P317, P342+P316, P362+P364, P403, P403+P233, P405, and P501 (click each P-code to see the statement)

This chemical does not meet GHS hazard criteria for < 0.1% (1 of 1247) of reports.

Danger

H315 (> 99.9%): Causes skin irritation [Warning Skin corrosion/irritation]

Chemical: Benzene, 2,4-diisocyanato-1-methyl-

Chemical: Benzene, diisocyanatomethyl-

Benzene, 2,4-diisocyanato-1-methyl- is listed on the EPA's Chemical Data Reporting (CDR) system. Manufacturers and importers of Benzene, 2,4-diisocyanato-1-methyl- 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)

SP - indicates a substance that is identified in a proposed Significant New Use Rule.

Status: Active Update: 22-09-2022 https://echa.europa.eu/registration-dossier/-/registered-dossier/14277

Restricted substance: 4-methyl-m-phenylene diisocyanate

Poison

Poison

This chemical is combustible. (NTP, 1992)

When heated to decomposition it emits very toxic fumes of cyanide and nitrogen oxides. Reacts violently with amines, alcohol, bases and warm water causing fire and explosion hazards. Avoid strong oxidizers, water, acids, bases, amines, etc., cause foam and splatter. Avoid heating. Hazardous polymerization may occur. Concentrated alkaline compound such as sodium hydroxide or tertiary amines may cause run-away polymerization. Slow, not hazardous polymerization may occur above 235F. (EPA, 1998)

· Combustible material: may burn but does not ignite readily.

Combustible. Gives off irritating or toxic fumes (or gases) in a fire. Risk of fire and explosion as a result of decomposition when heated.

Combustible liquid.

Due to its high flash point, toluene diisocyanate offers no serious risk of fire ... .

Combustible when exposed to heat or flame.

SYMPTOMS: Symptoms of exposure to this compound may include irritation of the skin, eyes and respiratory system. It may cause bronchial asthma. It may also cause bronchitis and pulmonary edema. Other symptoms may include nausea, vomiting and abdominal pain. Exposure may cause an asthmatic reaction with wheezing, dyspnea and cough. Some decrease in lung function in the absence of symptoms has been observed after long periods of exposure. Eosinophilia has been reported. It may cause sore throat, runny nose, diarrhea and bronchial spasm. High concentrations are destructive to tissues of the skin, eyes, mucous membranes, upper respiratory tract and digestive tract. Chemical or hypersensitive pneumonia may occur with flu-like symptoms (e.g. fever, chills). Irritation of the lungs may occur. Exposure may also cause laryngitis, shortness of breath and headache. Chest discomfort, including tightness and congestion, occurs. Insomnia has occurred. Death may result if inhaled, swallowed or absorbed through the skin. Skin contact may result in severe dermatitis. If the liquid is allowed to remain in contact with the skin, it may produce redness, swelling and blistering. It may also cause rashes and scaling. Skin sensitization can occur. Allergic eczema may also occur. Eye contact may cause severe irritation resulting in permanent damage if left untreated. It may cause keratitis and conjunctivitis. Eye contact may also cause lacrimation, smarting, burning and a prickling sensation. Ingestion may cause burns of the mouth and stomach. It may also have a corrosive effect on the stomach and esophagus. Gastrointestinal irritation may occur. Medical conditions aggravated by exposure to this compound include asthma, bronchitis, emphysema, bronchial hyperactivity, skin allergies and eczema.

Can cause death. Contact with skin may cause allergic eczema. Substance is very corrosive to eyes. Chronic exposure may cause chronic lung disease. As a vapor TDI is a powerful irritant to the respiratory tract. Chronic loss of respiratory function may occur. Acute asthmatic bronchitis or frank asthma may occur. A splash in the eyes of workmen has caused keratitis and conjunctivitis. This compound causes inflammation of the skin, also chemical pneumonitis and pulmonary edema. (EPA, 1998)

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

Toluene diisocyanate exists in two isomeric forms (2,4-toluene diisocyanate and 2,6-toluene diisocyanate) which have similar properties and effects. Toluene diisocyanate is produced commercially as an 80:20 (2,4-toluene diisocyanate:2,6-toluene diisocyanate) mixture of the two isomers. At room temperature, the mixture is a clear, pale yellow liquid with a sharp, pungent odor. It should be stored under refrigeration, away from light and moisture in a tightly closed container under an inert atmosphere. Toluene diisocyanate is insoluble in water and miscible with most common organic solvents.

2,4-Toluene diisocyanate is primarily used as a chemical intermediate in the production of polyurenthane products. 2,4-Toluene diisocyanate is extremely toxic from acute (short-term) and chronic (long-term) exposures. Acute exposure to high levels of 2,4-toluene diisocyanate in humans, via inhalation, results in severe irritation of the skin and eyes and affects the respiratory, gastrointestinal, and central nervous systems (CNS). Chronic inhalation exposure to 2,4-toluene diisocyanate in humans has resulted in significant decreases in lung function in workers, an asthma-like reaction characterized by wheezing, dyspnea, and bronchial constriction. Animal studies have reported significantly increased incidences of tumors of the pancreas, liver, and mammary glands from exposure to 2,4-toluene diisocyanate via gavage (experimentally placing the chemical in the stomach). The International Agency for Research on Cancer (IARC) has classified 2,4-toluene diisocyanate as a Group 2B, possible human carcinogen.

Liquid causes second degree burns after contact for a few minutes. [CHRIS] May cause skin sensitization and pulmonary edema; [ICSC] Cases of hypersensitivity pneumonitis (TDI HP and MDI HP) have been reported. [Rom, p. 388-90] Can cause lacrimation, photophobia, and lid edema; [HSDB] Danger of airway sensitization; [MAK] No major toxicological differences between the various isomers and commercial mixtures of TDI; TLV Basis: asthma; pulmonary function; eye irritation; [ACGIH] See Sennbro CJ, et al. Biological monitoring of exposure to toluene diisocyanate. Scand J Work Environ Health 2004;30(5):371-378] See DIISOCYANATES.

Reacts with water; Inhalation is the most dangerous route of exposure; May cause skin sensitization; Reports of eye irritation, corneal edema, and conjunctivitis; Inhalation may cause systemic effects and hypersensitivity reactions; Animal studies have demonstrated that dermal exposure can cause pulmonary sensitization; Inhalation of concentrations above 3.5 mg/m3 may cause chemical pneumonitis; [INCHEM PIMs] See Toluene 2,4-diisocyanate.

Most commonly produced as a mixture of isomers, with 80% 2,4- and 20% 2,6-isomers; Also available as a mixture of 65% 2,4- and 35% 2,6-isomers; [HSDB] This CAS# is for mixture of toluene-2,4-diisocyanate and toluene-2,6-diisocyanate; Reacts slowly with water evolving carbon dioxide; An irritant; May cause skin and respiratory sensitization; Excessive inhalation exposure may cause severe irritation, pulmonary edema, permanently decreased lung function, neurologic disorders, cholinesterase depression, and gastrointestinal distress; [Dow Chemical MSDS] See Medical Monitoring for Occupational Asthma Among Toluene Diisocyanate Production Workers in the United States. [PMID 29200134] See Toluene-2,4-diisocyanate and Toluene 2,6-diisocyanate.

2078 156

2078 156

Isocyanates and Isothiocyanates

Isocyanates and Isothiocyanates

Excerpt from ERG Guide 156 [Substances - Toxic and/or Corrosive (Combustible / Water-Sensitive)]:

If water gets below the surface of the liquid, it will turn to steam and cause frothing. Full protective clothing, including self-contained breathing apparatus, rubber gloves, boots and bands around legs, arms, and waist should be provided. No skin surface should be exposed.

Use powder, carbon dioxide, water in large amounts. 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. Half-upright position. Artificial respiration may be needed. Refer immediately for medical attention.

Remove contaminated clothes. Rinse and then wash skin with water and soap. Refer for medical attention .

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

Rinse mouth. Refer immediately 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.

Signs and Symptoms of Acute Toluene 2,4-Diisocyanate Exposure: Signs and symptoms of acute exposure to toluene 2,4-diisocyanate may be severe and include burning of the skin, eyes, nose, and throat. Cough, laryngitis, chest pain, tightness of the chest, bronchitis, asthma, emphysema, and enlargement of the right side of the heart may also occur. Gastrointestinal effects may include vomiting, diarrhea, and abdominal pain. Headache, insomnia, euphoria, depression, anxiety, paranoia, neuroses, and ataxia (incoordination) may also be noted.

General First Aid:

(General first aid procedures)

Separated from food and feedstuffs. Separated from : see Chemical Dangers. Store between 20 °C and 25 °C. Dry. Keep in a well-ventilated room. Store in an area without drain or sewer access. Refer to the manufacturer's instructions for proper storage conditions.

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

Biological Exposure Indices (BEI) [ACGIH] - Toluene diamine in urine (with hydrolysis) = 5 ug/g creatine at end of shift; [TLVs and BEIs]

0.001 [ppm]

Biological Exposure Indices (BEI) [ACGIH] - Toluene diamine in urine at end of shift = 5 ug/g creatine; [TLVs and BEIs]

To fight fire, use dry chemical, ... /carbon dioxide/.

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. Use water spray to knock-down vapors. /Toluene diisocyanate/

Where there is a fire involving isocyanates, carbon dioxide or powder extinguishers must be employed. Firemen must be equipped with self-contained breathing apparatus. /Isocyanates/

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. Use water spray to knock-down vapors.

To fight fire, use dry chemical, ... /carbon dioxide/.

Where there is a fire involving isocyanates, carbon dioxide or powder extinguishers must be employed. Firemen must be equipped with self-contained breathing apparatus. /Isocyanates/

Store in a cool, dry, well-ventilated location. Separate from acids, alkalies, oxidizing materials, amines, and water. Immediately remove and properly dispose of any spilled material.

Storage temp: 75-100 °F

Protect containers against physical damage. Store in a cool, dry, well- ventilated location, away from all possible ignition sources. Outdoors, detached or isolated storage is preferred. If stored in tanks, it should be blanketed with an inert gas such as nitrogen or with dry air. Care should be taken to prevent contact between isocyanates and strong alkali, which cause uncontrollable polymerization.

Storage in polyethylene containers is hazardous due to absorption of water through the plastic.

Isocyanates are transported in railroad tank cars, tank trucks, tanks in ships, containers, and drums. They are stored in steel tanks and processed in steel equipment. For long-term storage stainless steel is recommended. To avoid contamination by atmospheric moisture, a dry air or inert gas blanket is essential. /Isocyanates/

Store separated from amines, alcohols, bases and acids.

Spillage: Neutralize with special mixt (50% water, 45% alc, 5% concn ammonia water), collect leaking liq in sealable containers (extra personal protection: self-contained breathing apparatus).

Decontamination of spilled isocyanates and disposal of isocyanate waste are best conducted by using aqueous ammonia (3-8% concentrated ammonia solution in 90-95% water with 0.2-5% liquid detergent) or aqueous sodium carbonate (5-10% sodium carbonate in 90-95% water and 0.2-5% liquid detergent). An alcoholic solution (50% ethanol, isopropyl alcohol, or butanol; 45% water; and 5% concentrated ammonia) may be preferred because of the low miscibility of isocyanates with water. /Isocyanates/

AQUEOUS SOLUTIONS CONTAINING 10-20% (WT) OF A NONIONIC SURFACTANT, ARKOPAL-N100, WAS A USEFUL DECONTAMINATING AGENT FOR TOLYLENE DIISOCYANATE (TDI). THE SOLUTION CAN BE SPRAYED DIRECTLY ON SPILLS AS A LIQUID OR MAY BE APPLIED IN THE FORM OF A FOAM WHICH CAN BE GENERATED IN SUITABLE FIRE EXTINGUISHING EQUIPMENT. SOLID DECONTAMINANT FORMULATIONS WERE ALSO DEVELOPED WHICH CAN BE USED FOR GROUND SPILLS OF TDI.

Spillage: Neutralize with special mixt (50% water, 45% alc, 5% concn ammonia water), collect leaking liq in sealable containers (extra personal protection: self-contained breathing apparatus).

PRECAUTIONS FOR "CARCINOGENS": A high-efficiency particulate arrestor (HEPA) or charcoal filters can be used to minimize amt of carcinogen in exhausted air ventilated safety cabinets, lab hoods, glove boxes or animal rooms ... Filter housing that is designed so that used filters can be transferred into plastic bag without contaminating maintenance staff is avail commercially. Filters should be placed in plastic bags immediately after removal ... The plastic bag should be sealed immediately ... The sealed bag should be labelled properly ... Waste liquids ... should be placed or collected in proper containers for disposal. The lid should be secured & the bottles properly labelled. Once filled, bottles should be placed in plastic bag, so that outer surface ... is not contaminated ... The plastic bag should also be sealed & labelled. ... Broken glassware ... should be decontaminated by solvent extraction, by chemical destruction, or in specially designed incinerators. /Chemical Carcinogens/

Effect of water vapor on atmospheric toluene diisocyanate (TDI) was determined quantitatively. At 24 °C and atmospheric pressure maximum reduction of 50% was obtained for initial concentration of 0.4 and 0.034 ppm. The data suggest that increased humidity would be only marginally useful as a control method.

Excerpt from ERG Guide 156 [Substances - Toxic and/or Corrosive (Combustible / Water-Sensitive)]:

Caution : Mixing with water may result in a violent reaction. Sources of extreme heat or ignition including sparks or fire may result in formation of toxic nitrogen oxide gases.

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number U223, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.

Concentrated wastes from distillation equipment are preferably burnt in special waste incinerators. This also holds for complex and concentrated wastes, which cannot be regenerated by distillation. Because of the high reactivity of TDI /toluene diisocyanate/ waste waters contain only reaction products from the reaction with water. These can be biodegraded by treatment with activated sludge. Recommendable methods: Incineration, alkaline hydrolysis, discharge to sewer. Not recommendable: Landfill. Peer-review: Avoid contact or inhalation, add TDI to excess dilute alkali, and discharge to sewer. TDI can react explosively with moisture. (Peer-review conclusions of an IRPTC expert consultation (May 1985))

A potential candidate for rotary kiln incineration at a temperature range of 820 to 1,600 °C and residence times of seconds for liquids and gases, and hours for solids. A potential candidate for liquid injection incineration at a temperature range of 650 to 1,600 °C and a residence time of 0.1 to 2 seconds. A potential candidate for fluidized bed incineration at a temperature range of 450 to 980 °C and residence times of seconds for liquids and gases, and longer for solids.

This compound should be susceptible to removal from waste water by air stripping.

SRP: Wastewater from contaminant suppression, cleaning of protective clothing/equipment, or contaminated sites should be contained and evaluated for subject chemical or decomposition product concentrations. Concentrations shall be lower than applicable environmental discharge or disposal criteria. Alternatively, pretreatment and/or discharge to a permitted wastewater treatment facility is acceptable only after review by the governing authority and assurance that "pass through" violations will not occur. Due consideration shall be given to remediation worker exposure (inhalation, dermal and ingestion) as well as fate during treatment, transfer and disposal. If it is not practicable to manage the chemical in this fashion, it must be evaluated in accordance with EPA 40 CFR Part 261, specifically Subpart B, in order to determine the appropriate local, state and federal requirements for disposal.

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number U223, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.

Mean concentration of toluene diisocyanate in personal samples ranged from not detected-540 ug/cu m during polyurethane foam production and 2-1220 ug/cu m during polyurethane spray foam use(1).

In a Finnish study, toluene diisocyanate vapor concentrations ranged from 25-80 ug/cu m for pouring, 14-44 ug/cu m for paper stripping, and 1-8 ug/cu m for cutting. Personal monitors measured 9-34 ug/cu m and 5-30 ug/cu m of the 2,4-isomer for pouring and paper stripping, respectively. While 2,4-toluene diisocyanate constitutes 80% of toluene diisocyanate, and 2,6-toluene diisocyanate 20%, the 2,4-isomer is more reactive so that the concentration of the 2,6-isomer is higher in workplace air. The percentage of 2,4-toluene diisocyanate to total toluene diisocyanate measured with the personal monitors ranged from 29 to 69%(1).

Antidotes to cyanide poisoning include hydroxocobalamin and sodium nitrite, which release the cyanide from the cytochrome system, and rhodanase, which is an enzyme occurring naturally in mammals that combines serum cyanide with thiosulfate, producing comparatively harmless thiocyanate. Oxygen therapy can also be administered. (L97)

If the compound has been ingested, rapid gastric lavage should be performed using 5% sodium bicarbonate. For skin contact, the skin should be washed with soap and water. If the compound has entered the eyes, they should be washed with large quantities of isotonic saline or water. In serious cases, atropine and/or pralidoxime should be administered. Anti-cholinergic drugs work to counteract the effects of excess acetylcholine and reactivate AChE. Atropine can be used as an antidote in conjunction with pralidoxime or other pyridinium oximes (such as trimedoxime or obidoxime), though the use of '-oximes' has been found to be of no benefit, or possibly harmful, in at least two meta-analyses. Atropine is a muscarinic antagonist, and thus blocks the action of acetylcholine peripherally.

2,4-Toluene diisocyanate exerted a nonspecific inhibitory effect on the beta-adrenergic adenylate cyclase system of frog erythrocyte membrane preparation stimulated by the beta-agonist isoproterenol in vitro. This inhibition was dose-dependent, ie, incr concn of toluene diisocyanate (TDI) produced progressively greater inhibition. The similarity in response between toluene diisocyanate and the isocyanates 1,6-diisocyanatohexane & diphenylmethane 4,4'-diisocyanate suggests that the isocyanate group plays a critical role in inhibiting the responsiveness of this system to beta-agonists.

Cancer, Respiratory (From the Nose to the Lungs)

Eyes, skin, respiratory system

Exposure to high levels of cyanide for a short time harms the brain and heart and can even cause coma, seizures, apnea, cardiac arrest and death. Chronic inhalation of cyanide causes breathing difficulties, chest pain, vomiting, blood changes, headaches, and enlargement of the thyroid gland. Skin contact with cyanide salts can irritate and produce sores. (L96, L97)

Acute exposure to cholinesterase inhibitors can cause a cholinergic crisis characterized by severe nausea/vomiting, salivation, sweating, bradycardia, hypotension, collapse, and convulsions. Increasing muscle weakness is a possibility and may result in death if respiratory muscles are involved. Accumulation of ACh at motor nerves causes overstimulation of nicotinic expression at the neuromuscular junction. When this occurs symptoms such as muscle weakness, fatigue, muscle cramps, fasciculation, and paralysis can be seen. When there is an accumulation of ACh at autonomic ganglia this causes overstimulation of nicotinic expression in the sympathetic system. Symptoms associated with this are hypertension, and hypoglycemia. Overstimulation of nicotinic acetylcholine receptors in the central nervous system, due to accumulation of ACh, results in anxiety, headache, convulsions, ataxia, depression of respiration and circulation, tremor, general weakness, and potentially coma. When there is expression of muscarinic overstimulation due to excess acetylcholine at muscarinic acetylcholine receptors symptoms of visual disturbances, tightness in chest, wheezing due to bronchoconstriction, increased bronchial secretions, increased salivation, lacrimation, sweating, peristalsis, and urination can occur. Certain reproductive effects in fertility, growth, and development for males and females have been linked specifically to organophosphate pesticide exposure. Most of the research on reproductive effects has been conducted on farmers working with pesticides and insecticdes in rural areas. In females menstrual cycle disturbances, longer pregnancies, spontaneous abortions, stillbirths, and some developmental effects in offspring have been linked to organophosphate pesticide exposure. Prenatal exposure has been linked to impaired fetal growth and development. Neurotoxic effects have also been linked to poisoning with OP pesticides causing four neurotoxic effects in humans: cholinergic syndrome, intermediate syndrome, organophosphate-induced delayed polyneuropathy (OPIDP), and chronic organophosphate-induced neuropsychiatric disorder (COPIND). These syndromes result after acute and chronic exposure to OP pesticides.

LC50; Species: Pimephales promelas (Fathead Minnow) length 3.2-4.2 cm; Conditions: freshwater, static, 22 °C, pH 7.2-7.9, hardness 40-48 mg/L CaCO3, alkalinity 30-35 mg/L CaCO3; Concentration: 194900 ug/L for 24 hr (95% confidence interval: 143800-278600 ug/L)

LC50; Species: Pimephales promelas (Fathead Minnow) length 3.2-4.2 cm; Conditions: freshwater, static, 22 °C, pH 7.2-7.9, hardness 40-48 mg/L CaCO3, alkalinity 30-35 mg/L CaCO3; Concentration: 172100 ug/L for 48 hr (95% confidence interval: 118100-250400 ug/L)

LC50; Species: Pimephales promelas (Fathead Minnow) length 3.2-4.2 cm; Conditions: freshwater, static, 22 °C, pH 7.2-7.9, hardness 40-48 mg/L CaCO3, alkalinity 30-35 mg/L CaCO3; Concentration: 164500 ug/L for 96 hr (95% confidence interval: 108800-240400 ug/L)

TERRESTRIAL FATE: 2,4-Toluene diisocyanate reacts readily with compounds containing active hydrogens, such as water, acids, and alcohols(1). 2,4-Toluene diisocyanate is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 8X10-3 mm Hg(2). Based on data for the mixture toluenediisocyanate (TDI) (2,4- plus 2,6-isomers), 2,4-toluene diisocyanate may not be stable in the terrestrial environment(SRC). In a simulated spill, 5 kg of TDI in a container was covered with 50 kg of sand and 5 kg of water at ambient temperatures and samples taken from the top and bottom of the sand pile(3). After 24 hr, 5.5% of the TDI remained unreacted and after 8 days 3.5% remained(5). The reaction product was largely polyureas(3). Ten days after a spill of 13 tons of TDI onto a swampy, wet forest soil, TDI and toluenediamines were found in the soil(2,3). The TDI solidified and the area was covered with sand. The soil concentration of TDI and toluenediamine combined declined from the parts per thousand to parts per million range between 10 days and 12 weeks after the spill(3). One year later, neither TDI nor toluenediamine could be found in soil samples(4). After 6 years, only TDI-derived polyureas were found at the site in soil samples at depths to 100 cm(4). A 0% theoretical BOD for 2,4-toluene diisocyanate incubated four weeks using an activated sludge inoculum in the Japanese MITI test(5) suggests that biodegradation of 2,4-toluene diisocyanate is not an important environmental fate process in soil(SRC).

AQUATIC FATE: 2,4-Toluene diisocyanate reacts readily with compounds containing active hydrogens, such as water, acids, and alcohols(1). Based on data for the mixture, 2,4-toluene diisocyanate may not be stable in the aquatic environment(SRC). When low concentrations of toluene diisocycanate (TDI) are released into model river or seaway systems, it hydrolyzes within a day(2). An experiment was performed to simulate a spill into running water by pouring 0.5 liter of TDI into 20 liters of slowly overflowing water(3). Barely detectable amounts of toluenediamine were present in the overflow samples. As in the stagnant water simulation, a crust formed that contained <0.5% of the original TDI after 35 days(3). A 0% theoretical BOD for 2,4-toluenediisocyante incubated four weeks using an activated sludge inoculum in the Japanese MITI test(4) suggests that biodegradation is not an important environmental fate process in water(SRC).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 2,4-toluene diisocyanate, which has a vapor pressure of 8X10-3 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase 2,4-toluene diisocyanate 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 1.7 days(SRC), calculated from its rate constant of 6.3X10-12 cu cm/molecule-sec at 25 °C(SRC) determined using a structure estimation method(3). Atmospheric degradation may also occur through contact with clouds, fog or rain. 2,4-Toluene diisocyanate 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).

TERRESTRIAL FATE: Toluene diisocyanate reacts readily with compounds containing active hydrogens, such as water, acids, and alcohols(1); therefore, volatilization from moist soil surfaces is not expected to be an important environmental fate process. In one experiment simulating a spill, 5.5% of the toluene diisocyanate (TDI) remained after 24 hours and in a field situation, the concentration of TDI had declined to the ppm level in 12 weeks(2). Toluene diisocyanate is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 2.3X10-2 mm Hg(3).

AQUATIC FATE: Toluene diisocyanate reacts readily with compounds containing active hydrogens, such as water, acids, and alcohols(1); therefore, volatilization from water and moist soil surfaces is not expected to be an important environmental fate process. In one experiment simulating a spill, 5.5% of the toluene diisocyanate (TDI) remained after 24 hours and in a field situation, the concentration of TDI had declined to the ppm level in 12 weeks(2). Bioconcentration in aquatic organisms is not expected to be an important environmental fate process due to this rapid hydrolysis(SRC).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), toluene diisocyanate (TDI), which has a vapor pressure of 2.3X10-2 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase toluene diisocyanate 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 20 hrs(SRC), calculated from its rate constant of 7.07X10-12 cu cm/molecule-sec at 25 °C(3). Atmospheric degradation may also occur through contact with clouds, fog or rain. Toluene diisocyanate 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).

Dermatotoxin - Skin burns.

Skin Sensitizer - An agent that can induce an allergic reaction in the skin.

Dermatotoxin - Skin burns.

The substance can be absorbed into the body by inhalation of its vapour, by inhalation of its aerosol and by ingestion.

inhalation, ingestion, skin and/or eye contact

Oral (L96) ; inhalation (L96) ; dermal (L96)

Oral (L96) ; inhalation (L96) ; dermal (L96)

Cyanide is an inhibitor of cytochrome c oxidase in the fourth complex of the electron transport chain (found in the membrane of the mitochondria of eukaryotic cells). It complexes with the ferric iron atom in this enzyme. The binding of cyanide to this cytochrome prevents transport of electrons from cytochrome c oxidase to oxygen. As a result, the electron transport chain is disrupted and the cell can no longer aerobically produce ATP for energy. Tissues that mainly depend on aerobic respiration, such as the central nervous system and the heart, are particularly affected. Cyanide is also known produce some of its toxic effects by binding to catalase, glutathione peroxidase, methemoglobin, hydroxocobalamin, phosphatase, tyrosinase, ascorbic acid oxidase, xanthine oxidase, succinic dehydrogenase, and Cu/Zn superoxide dismutase. Cyanide binds to the ferric ion of methemoglobin to form inactive cyanmethemoglobin. (L97)

2,4-Toluene diisocyanate is a cholinesterase or acetylcholinesterase (AChE) inhibitor. A cholinesterase inhibitor (or 'anticholinesterase') suppresses the action of acetylcholinesterase. Because of its essential function, chemicals that interfere with the action of acetylcholinesterase are potent neurotoxins, causing excessive salivation and eye-watering in low doses, followed by muscle spasms and ultimately death. Nerve gases and many substances used in insecticides have been shown to act by binding a serine in the active site of acetylcholine esterase, inhibiting the enzyme completely. Acetylcholine esterase breaks down the neurotransmitter acetylcholine, which is released at nerve and muscle junctions, in order to allow the muscle or organ to relax. The result of acetylcholine esterase inhibition is that acetylcholine builds up and continues to act so that any nerve impulses are continually transmitted and muscle contractions do not stop. Among the most common acetylcholinesterase inhibitors are phosphorus-based compounds, which are designed to bind to the active site of the enzyme. The structural requirements are a phosphorus atom bearing two lipophilic groups, a leaving group (such as a halide or thiocyanate), and a terminal oxygen.

U223; As stipulated in 40 CFR 261.33, when toluene diisocyanate, as a commercial chemical product or manufacturing chemical intermediate or an off-specification commercial chemical product or a manufacturing chemical intermediate, becomes a waste, it must be managed according to Federal and/or State hazardous waste regulations. Also defined as a hazardous waste is any residue, contaminated soil, water, or other debris resulting from the cleanup of a spill, into water or on dry land, of this waste. Generators of small quantities of this waste may qualify for partial exclusion from hazardous waste regulations (40 CFR 261.5).

U223; As stipulated in 40 CFR 261.33, when toluene diisocyanate, as a commercial chemical product or manufacturing chemical intermediate or an off-specification commercial chemical product or a manufacturing chemical intermediate, becomes a waste, it must be managed according to Federal and/or State hazardous waste regulations. Also defined as a hazardous waste is any residue, contaminated soil, water, or other debris resulting from the cleanup of a spill, into water or on dry land, of this waste. Generators of small quantities of this waste may qualify for partial exclusion from hazardous waste regulations (40 CFR 261.5).

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. Benzene, 2,4-diisocyanato-1-methyl- is included on this list. Effective date: 6/1/87; Sunset date: 6/1/97.

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. Benzene, 1-3-diisocyanatomethyl- is included on this list. Effective date: 6/1/87; Sunset date: 6/1/97.

This action promulgates standards of performance for equipment leaks of Volatile Organic Compounds (VOC) in the Synthetic Organic Chemical Manufacturing Industry (SOCMI). The intended effect of these standards is to require all newly constructed, modified, and reconstructed SOCMI process units to use the best demonstrated system of continuous emission reduction for equipment leaks of VOC, considering costs, non air quality health and environmental impact and energy requirements. Toluene 2,4-diisocyanate is produced, as an intermediate or a final product, by process units covered under this subpart.

Listed as a hazardous air pollutant (HAP) generally known or suspected to cause serious health problems. The Clean Air Act, as amended in 1990, directs EPA to set standards requiring major sources to sharply reduce routine emissions of toxic pollutants. EPA is required to establish and phase in specific performance based standards for all air emission sources that emit one or more of the listed pollutants. 2,4-Toluene diisocyanate is included on this list.

This action promulgates standards of performance for equipment leaks of Volatile Organic Compounds (VOC) in the Synthetic Organic Chemical Manufacturing Industry (SOCMI). The intended effect of these standards is to require all newly constructed, modified, and reconstructed SOCMI process units to use the best demonstrated system of continuous emission reduction for equipment leaks of VOC, considering costs, non air quality health and environmental impact and energy requirements. Toluene diisocyanates (mixture) is produced, as an intermediate or a final product, by process units covered under this subpart.

Persons in charge of vessels or facilities are required to notify the National Response Center (NRC) immediately, when there is a release of this designated hazardous substance, in an amount equal to or greater than its reportable quantity of 100 lb or 45.4 kg. The toll free number of the NRC is (800) 424-8802. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV. D.3.b).

Releases of CERCLA hazardous substances are subject to the release reporting requirement of CERCLA section 103, codified at 40 CFR part 302, in addition to the requirements of 40 CFR part 355. Toluene 2,4-diisocyanate is an extremely hazardous substance (EHS) subject to reporting requirements when stored in amounts in excess of its threshold planning quantity (TPQ) of 500 lbs.

Persons in charge of vessels or facilities are required to notify the National Response Center (NRC) immediately, when there is a release of this designated hazardous substance, in an amount equal to or greater than its reportable quantity of 100 lb or 45.4 kg. The toll free number of the NRC is (800) 424-8802. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV. D.3.b).

Exposure of workers to isocyanates may result in irritation and/or sensitization of the resp tract. An immunologic mechanism for sensitization has been presented. This investigation explored whether, as a possible mechanism for the irritation reaction, the toxic resp effect of isocyanates might be due to their ability to inhibit cholinesterase. Molar ratios of 50:1 or greater were required for 50% inhibition of purified human serum cholinesterase by 2,4-toluene diisocyanate. ...

... The sensitizing agent /such as toluene diisocyanate/ acts in vivo to haptenate self-proteins, and this haptenated self-protein serves as the stimulus for generation of the allergic immune response.

It ... has been reported that toluene diisocyanate forms antigenic complexes with proteins, transforms lymphocytes in sensitized individuals, induces skin-sensitizing antibodies in animals, and induces specific antibody formation.

Toluene diisocyanate (TDI) has ... been found to suppress the incr of intracellular cyclic adenosine monophosphate (cAMP) by the beta-agonist isoproterenol in peripheral blood lymphocytes indicative of a pharmacologic mechanism of action. Research data suggest that isocyanates may cause nonspecific inhibition of a variety of membrane receptors & enzyme systems. Both immunologic & nonimmunologic mechanisms appear to be involved. Although much research has been directed toward the mechanism of isocyanate-induced disease, the complete pathophysiology remains unknown. /Toluene diisocyanate/

The in vivo exposure to an asthmogenic stimulus, toluene diisocyanate, causes airway epithelial damage associated with inflammation and increased bronchial hyperresponsiveness. The latter mechanisms might partly be mediated by the release of eicosanoids from bronchial epithelial cells. Previously it has been demonstrated that the in vitro exposure of bronchial epithelial cells to toluene diisocyanate results in the release of immunoreactive 15-hydroxyeicosatetraenoic acid, a product of activation of the 15-lipoxygenase pathway with inflammatory properties. Present study shows that toluene diisocyanate induced release of 15-hydroxyeicosatetraenoic acid from epithelial cells can be prevented by nedocromil sodium, an anti-asthmatic drug with anti-inflammatory properties. This mode of action of the compound may explain its clinical effectiveness in asthma.

Isocyanates likely differ in toxicity due to factors beyond inherent reactivity of the NCO functional group, such as properties (electrophilic, lipophilic, three-dimensional structure, etc.) of the moiety attached to the NCO group, deposition site in the lungs, or concomitant exposures such as solvents. Such properties likely determine a molecule's permeability through biological barriers and ability to get to a target reaction site. The moiety attached to the NCO group appears to be responsible in part for variations in biochemical reactivity and toxicity within the isocyanate class. For example, aromatic isocyanates react orders of magnitude faster than aliphatic isocyanates in reactions with active hydrogen compounds as a result of the electrophilic effect of the aromatic ring on the N=C=O bond. It has been suggested that the more lipophilic isocyanates such as MDI and polymeric MDI (pMDI) may penetrate biological barriers easier, thus reaching biologically susceptible sites faster than less lipophilic isocyanates such as isocyanurate. Based on the interplay of such factors (reactivity, lipid solubility, and deposition site) one would expect a range of toxicities for different isocyanates. /Isocyanates/

Whole body: a few hours; [TDR, p. 1156]

The toxicokinetics of 2,4- and 2,6-toluenediisocyanates in 11 chronically exposed workers at two flexible foam polyurethane production plants have been reported. ... The half life in urine ranged from 5.8 to 11 days for 2,4 and 2.6 toluene diamines. The differences in exposure were reflected by the plasma toluene diamine concentrations. The mean half life in plasma was 21 (range, 14-34) days for 2,4-toluene diamine and 21 (16-26) days for 2,6-toluene diamine. The study showed that the half life in plasma of chronically exposed workers for 2,4- and 2,6-toluene diamine was twice as long as for volunteers with short term exposure.

Two men were exposed to toluene diisocyanate atmospheres at three different air concn (ca 25, 50 & 70 ug/cu m). The toluene diisocyanate atmospheres were generated by a gas-phase permeation method, & the exposures were performed in an 8-cu m stainless-steel test chamber. ... The isomeric composition of the air in the test chamber was 30% 2,4-toluene diisocyanate and 70% 2,6-toluene diisocyanate. ... In plasma, 2,4- & 2,6-toluenediamine showed a rapid-phase elimination half-time of ca 2-5 hr, & that for the slow phase was greater than 6 days. ... The cumulated amount of 2,4-toluenediamine excreted in the urine over 24 hr was ca 15%-19% of the estimated inhaled dose of 2,4-toluene diisocyanate, & that of 2,6-toluenediamine was ca 17%-23% of the inhaled dose of 2,6-toluene diisocyanate.

The toxicokinetics of 2,4- and 2,6-toluenediisocyanates in 11 chronically exposed workers at two flexible foam polyurethane production plants have been reported. ... The half life in urine ranged from 5.8 to 11 days for 2,4 and 2.6 toluene diamines. The differences in exposure were reflected by the plasma toluene diamine concentrations. The mean half life in plasma was 21 (range, 14-34) days for 2,4-toluene diamine and 21 (16-26) days for 2,6-toluene diamine. The study showed that the half life in plasma of chronically exposed workers for 2,4- and 2,6-toluene diamine was twice as long as for volunteers with short term exposure.

Two men were exposed to toluene diisocyanate atmospheres at three different air concn (ca 25, 50 & 70 ug/cu m). The toluene diisocyanate atmospheres were generated by a gas-phase permeation method, & the exposures were performed in an 8-cu m stainless-steel test chamber. ... The isomeric composition of the air in the test chamber was 30% 2,4-toluene diisocyanate and 70% 2,6-toluene diisocyanate. ... In plasma, 2,4- & 2,6-toluenediamine showed a rapid-phase elimination half-time of ca 2-5 hr, & that for the slow phase was greater than 6 days. ... The cumulated amount of 2,4-toluenediamine excreted in the urine over 24 hr was ca 15%-19% of the estimated inhaled dose of 2,4-toluene diisocyanate, & that of 2,6-toluenediamine was ca 17%-23% of the inhaled dose of 2,6-toluene diisocyanate.

65 % of quantitated urinary metabolites were acid-labile conjugates. Free /toluene diamine (TDA)/ and its mono - and diaceyl derivatives /were/ present in urine. 94 % of (14)C-dose /was present/ in urine, feces, tissues and carcass 48 hrs after dosing. 81 % in feces, 8 % in urine, 4 % tissues (highest in GI tract). ... /In/expired air (14)C, /was/ negligible. ... /Toluene diamine/

In man, tolylene-2,4-diisocyanate is metab into 2,4-diaminotoluene. ...

Inhalation exposure to toluene 2,4-diisocyanate results primarily in the formation of acid labile conjugates, with little or no toluene 2,4-diamine being formed.

Subjects exposed to 2,4-TDI and 2,6-TDI in a test chamber (5.5 ppb for 7.5 hours) had the corresponding amines in plasma and urine - identified by gas chromatography-mass spectrometry (GC-MS) after hydrolysis. Elimination from plasma was slow. Elimination in urine had a slow and a fast phase, the latter with a biological half time of one to two hours. Two persons were exposed to three concentrations in the range 3.4-9.7 ppb for 4 hours, and there was a correlation between TDI levels in air and TDA levels in plasma. Elimination from plasma had two phases. The biological half time was two to five hours for the fast phase and more than six days for the slow phase.

A technique for detecting urinary amine metabolites in rats exposed to toluene diisocyanate was evaluated. Skin tissue of rats was exposed to 40% toluene-2,4-diisocyanate soln in di-n-butyl-ether liquid. Rats were exposed daily for 3 hr on 4 consecutive days. Urine was collected in metabolic cages for 18 hr after the last exposure. Chromatographic techniques were used for nitrogen selective detection of non-derivatized amines. An autolinear temperature programmer was employed to analyze derivatized amine. The identity of the amine was confirmed by gas chromatography/mass spectrometry. A linear correlation was found between toluene-2,4-diamine added to urine & peak height. Peak height & recovery from the non hydrolyzed and from the hydrolyzed urine was about 85 & 70%, respectively. No free toluene-2,4-diamine or free toluene-2,4-diisocyanate was detected in the urine of rats exposed to toluene-2,4-diisocyanate. The concentration of toluene-2,4-diamine in hydrolyzed urine was 1.5ug/mL. Gas chromatography/mass spectrometry confirmed the identity of the amine. /This/ highly sensitive technique tested is easy to apply & is effective for trace assays of amines.

The major metabolites of toluene diisocyanates in both animals and humans are toluene diamines and their acetylated products. /Toluene diisocyanates/

... The route dependent metabolism of (14)C toluene 2,4-diisocyanate and (14)C toluene 2,4 diamine in Fischer 344 rats /was investigatd/. Forty-eight hours after an oral dose of 60 mg (14)C toluene 2,4 diisocyanate/kg bw, 81%, 8% and 4% of the radioactivity was found in the feces, urine and tissue/carcass/gastrointestinal tract contents, respectively. Markedly different results were obtained following inhalation exposure of rats to 2 ppm (14.2 mg/cu m) (14)C toluene 2,4 diisocyanate for 2 hr. Forty eight hours after exposure, 47%, 15% and 34% of the recovered radioactivity was in the feces, urine and tissue/carcass/gastrointestinal tract contents, respectively.

In comparative studies, (14)C toluene 2,4-diamine, the hydrolysis product of (14)C toluene 2,4-diisocyanate, was administered to rats at doses of 3 mg/kg bw (orally or intravenously) and 60 mg/kg bw orally. After 48 hr, the distribution of radioactivity was similar in all cases (urine, 64-72%; feces, 20-31%; and tissue/carcass/gastrointestinal tract, 2-5%). Comparison of the toluene 2,4-diisocyanate inhalation group with the oral toluene 2,4-diisocyanate and toluene 2,4-diamine treatment groups indicated that a larger percentage of the inhaled radioactivity was in the tissues/carcass and that excretion of radioactivity into the urine was slower following toluene 2,4-diisocyanate inhalation.

Following inhalation or oral exposure to (14)C toluene 2,4-diisocyanate, about 90% and 65% of the quantitated urinary metabolites were acid labile conjugates. In contrast, only 16 39% of the urinary metabolites were conjugated following oral administration of (14)C toluene 2,4-diamine.

Inhalation exposure to toluene 2,4-diisocyanate results primarily in the formation of acid labile conjugates, with little or no toluene 2,4-diamine being formed. This suggests that the disposition of inhaled toluene 2,4-diisocyanate is quite different from that of orally administered toluene 2,4-diisocyanate or of intravenously or orally administered toluene 2,4-diamine.

For more Absorption, Distribution and Excretion (Complete) data for 2,4-TOLUENE DIISOCYANATE (6 total), please visit the HSDB record page.

... Rats were exposed to /(14)C-toluene diisocyanate (TDI)/ vapors at concentrations ranging from 0.026 to 0.821 ppm for 4 hr. All tissues examined showed detectable quantities of radioactivity, with the airways, gastrointestinal system and blood having the highest levels which increased with exposure concentration. The concentration of radioactivity in the bloodstream after exposure was linear with respect to dose. The majority (74-87%) of the label associated with the blood was recovered in the plasma, and of this, 97-100% of the (14)C existed in the form of biomolecular conjugates. Analysis of stomach contents shows that the majority of the label is also associated with high (> 10 kDa) molecular weight species. While a larger percentage (28%) of the label is found in the low molecular weight fraction relative to blood, this low molecular weight labeled material represents at least eight different components. Thus, over the vapor exposure concentrations and time tested, it appears that conjugation is the predominant reaction and that free /toluenediamine (TDA)/ is not a primary in vivo reaction product under the conditions tested.

2,4-Toluene diisocyanate is used as a chemical intermediate in the production of polyurethane products such as foams, coatings, and elastomers.

Occupational asthma reported in floor varnishers and in workers manufacturing polyurethane foams and elastomers; [Malo]

Painting (Pigments, Binders, and Biocides) [Category: Paint]

This is the crude form of toluene 2,4-diisocyanate (2,4-TDI) with an unspecified isomer ratio commercially available but not usually used; [INCHEM PIMs] Used to make polyurethane foams and coatings, elastomeric coating systems, adhesives, and sealants; Occupational exposure occurs in adhesives production, insulation application, resin and lacquer production, chemical synthesis, paint spraying, polyurethane foam production, work with rubber, shipbuilding, textile processing, and wire coating; [INCHEM PIMs]

Textiles (Fiber & Fabric Manufacturing) [Category: Industry]

Used to make polyurethanes, polyurethane foams, elastomers, and coatings, as a cross-linker for nylon-6, and hardener for adhesives and finishes; [HSDB]

(1972) 2.82X10+10 GRAMS

(1975) 5.13X10+10 GRAMS

(1984) 6.27x10+10 g /TOLUENE DIISOCYANATES/

(1998) 289 million. Average annual exports during the 1993-1998 period amounted to 288 million pounds.

(1983) 2.00X10+7 G /FOR 2,4-TDI DIMER/

(1983) 8.94X10+8 G /FOR TDI(UNMIXED)/

(1983) 2.00X10+9 G /FOR 2,4 (AND 2,6) TDI/

(1972) NEGLIGIBLE

(1975) NEGLIGIBLE

(1983) 8.94X10+8 g /FOR TDI (UNMIXED)/

2023: 100,000,000 - <500,000,000 lb

(1984) 2.41X10+11 G (EST FOR 2,4 ISOMER) /BASED ON VALUE FOR 80:20 MIXTURE 2,4-2,6 TDI/

Benzene, 2,4-diisocyanato-1-methyl- 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#2322]

Production volume for non-confidential chemicals reported under the 2006 Inventory Update Rule. Chemical: Benzene, 2,4-diisocyanato-1-methyl-. Aggregated National Production Volume: 10 to < 50 million pounds.

(1972) 1.90X10+11 GRAMS

80% 2,4:20% 2,6 MIXT REPRESENTS OVER 95% OF INDUSTRIAL USAGE ... .

90% FLEXIBLE FOAMS-MOLDED FLEXIBLE; 5% COATINGS; 3% ELASTOMERS; 2% OTHER (1984 EST) /FOR 80:20 MIX OF 2,4-2,6 ISOMER/

CHEMICAL PROFILE: Toluene Diisocyanate. Flexible urethane foams, 65%; (furniture, 28%; transportation, 16%; carpet underlay, 9%; bedding, 6%; other foam uses, 6%;) exports, 22%; rigid foams, 5%; polyurethane coatings, 4%; elastomers, 2%; miscellaneous non-foam uses, 2%.

CHEMICAL PROFILE: Toluene diisocyanate. Demand: 1986: 650 million lb; 1987: 695 million lb; 1991 /projected/: 720 million lb (Includes exports, imports are negligible).

Flexible urethane foams, 90% (furniture, 32%; transportation, 30%; carpet underlay, 10%; bedding, 10%; packaging, 8%; other foam uses, 10%); polyurethane coatings, 4%; cast elastomers, 2%; sealants, 2%; miscellaneous, including polyurethane fibers, 2%.

For more Consumption Patterns (Complete) data for TOLUENE DIISOCYANATE (6 total), please visit the HSDB record page.

Usually prepared from toluene-2,4-diamine and phosgene.

Toluene is the primary raw material for industrial TDI manufacture. The classical dinitration of toluene with mixed acid produces a mixture of 2,4- and 2,6-dinitro isomers in a ratio of 80:20. Catalytic reduction of these derivatives under hydrogen pressure leads to the corresponding diamines TDA, which are subsequently treated with phosgene to give TDI.

... (80% 2,4-isomer and 20% 2,6-isomer) is produced commercially by nitrating toluene with nitric acid-sulfuric acid mixture and catalytically reducing resultant dinitrotoluene ... to toluenediamine mixture. ... This is dissolved in monochlorobenzene or ortho-dichlorobenzene and treated with phosgene. ... /Mixture of 2,4- & 2,6-isomers/

Toluene is the primary raw material for industrial TDI manufacture. The classical dinitration of toluene with mixed acid produces a mixture of 2,4- and 2,6-dinitro isomers in a ratio of 80:20. Catalytic reduction of these derivatives under hydrogen pressure leads to the corresponding diamines TDA, which are subsequently treated with phosgene to give TDI.

NITRATION OF TOLUENE, FOLLOWED BY REDUCTION TO DIAMINE, REACTION WITH PHOSGENE, PURIFICATION, AND RECOVERY OF COPRODUCT HYDROGEN CHLORIDE.

Grades: 100% 2,4-isomer; 80% and 65% 2,4-isomer both mixed with 2,6-isomer.

Commonly used isomers are 2,4-toluene diisocyanate and 2,6-toluene diisocyanate, commercially avail in following 3 ratios: 1) 100% 2,4-; 2) 80% 2,4-: 20% 2,6-; 3) 65% 2,4-: 35% 2,6-; 80% 2,4-: 20% 2,6 mixture represents over 95% of industrial usage ... .

The most common grade is a mixed isomer product containing 80% 2,4- and 20% 2,6-isomers. A second grade containing 65% 2,4- and 35% 2,6-isomers is also available as well as the pure 2,4-isomer.

Miscellaneous Manufacturing

Benzene, 2,4-diisocyanato-1-methyl-: ACTIVE

Method of purification: distillation to remove hydrogen chloride.

Commercial toluene diisocyanate (TDI) typically contains 80% of 2,4-toluene diisocyanate.

... Many /spandex formulations/ are based on ... 2,4-toluene diisocyanate. ...

Diisocyanates used in the polyurethane industry pose a possible threat to workers exposed to them. A method for generating low concn was developed using tetrafluoroethylene Teflon permeation tubes. The tubes were prepared by sealing in clean spaghetti tubing with solid tetrafluoroethylene Teflon rod held in place with crimped aluminum Swagelok ferrules. Using a commercially avail air bath capable of maintaining a temp within 0.05 deg K, the permeation tubes were kept at 303, 323 and 343 deg K toluene diisocyanate was swept from the thermostated chamber with dry nitrogen and further diluted with clean dry air to the desired concn. Permeation rates for the thick wall tube were 2.14 ng/min/cm at 303 deg K, 10.66 at 323 deg K and 42.84 at 343 deg K. For the thin wall tube, the permeation rates were 8.30 ng/min/cm at 303 deg K, 45.39 at 323 deg K and 179.62 at 343 deg K. /Diisocyanates/