3,3′-Dimethoxy-4,4′-biphenylene diisocyanate

296.27700

296.28

5AC9L5Y28Y

5040

2206

DTXSID6020484

Gray to brown powder

77.32000

3.30540

3,3'-dimethoxybenzidine-4,4'-diisocyanate appears as gray to brown powder or dark beige sandy powder. Melting point 112°C. Insoluble in water. Toxic by inhalation and ingestion. A skin irritant. Used in making plastics.

1.19g/cm3

121-122 °C

210-211 °C @ Press: 3 Torr

170 °F

1.569

Soluble in ketones and esters

Hydrolysed to 3,3'-dimethoxybenzidine; emits toxic fumes of nitric oxide when heated to decomposition.

Insoluble in water.

Ethers

3,3'-DIMETHOXYBENZIDINE-4,4'-DIISOCYANATE may react with amines, aldehydes, alcohols, alkali metals, ketones, mercaptans, strong oxidizing agents, hydrides, phenols, and peroxides with vigorous releases of heat. May undergo polymerization reactions with acids and bases.

UN 2811 6.1/PG 2

3

R23/24/25

S26;S36;S45

T

Stable, but air and water sensitive. Incompatible with strong oxidizing agents, strong acids.

P261, P264, P270, P271, P280, P301+P310, P302+P352, P304+P340, P311, P312, P321, P322, P330, P361, P363, P403+P233, P405, P501

H301

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.

3,3'-Dimethoxybenzidine-4,4'-diisocyanate; IARC Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Humans: Some Chemicals Used in Plastics and Elastomers, International Agency for Research on Cancer, 39: 279-86 (1986). The human carcinogenic risk posed by exposure to 3,3'-dimethoxybenzidine-4,4'-diisocyanate.|Bioassay of 3,3'-Dimethoxybenzidine-4,4'-diisocyanate for Possible Carcinogenicity (1979) Technical Rpt Series No. 128 DHEW Pub No. (NIH) 79-1383, U.S. Department of Health Education and Welfare, National Cancer Institute, Bethesda, MD 20014

Flash point data for this chemical are not available; however, it is probably combustible. (NTP, 1992)

|Danger|H301 (100%): Toxic if swallowed [Danger Acute toxicity, oral]|P261, P264, P270, P271, P280, P301+P310, P302+P352, P304+P340, P311, P312, P321, P322, P330, P361, P363, P403+P233, P405, and P501|Aggregated GHS information provided by 38 companies from 1 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Excerpt from ERG Guide 155 [Substances - Toxic and/or Corrosive (Flammable / Water-Sensitive)]: As an 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, in the downwind direction, as necessary, the isolation distance shown above. FIRE: If tank, rail car or tank truck 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, 2016)

SMALL SPILLS AND LEAKAGE: If a spill of this chemical occurs, FIRST REMOVE ALL SOURCES OF IGNITION, then you should dampen the solid spill material with acetone and transfer the dampened material to a suitable container. Use absorbent paper dampened with acetone to pick up any remaining material. Seal your contaminated clothing and the absorbent paper in a vapor-tight plastic bag for eventual disposal. Solvent wash all contaminated surfaces with acetone followed by washing with a soap and water solution. Do not reenter the contaminated area until the Safety Officer (or other responsible person) has verified that the area has been properly cleaned. STORAGE PRECAUTIONS: You should store this material in a refrigerator. (NTP, 1992)

MINIMUM PROTECTIVE CLOTHING: If Tyvek-type disposable protective clothing is not worn during handling of this chemical, wear disposable Tyvek-type sleeves taped to your gloves. RECOMMENDED RESPIRATOR: Where the neat test chemical is weighed and diluted, wear a NIOSH-approved half face respirator equipped with a combination filter cartridge, i.e. organic vapor/acid gas/HEPA (specific for organic vapors, HCl, acid gas, SO2 and a high efficiency particulate filter). (NTP, 1992)|Vapor Concentration: 0.2 ppm or less: Any supplied-air respirator or any self-contained breathing apparatus. 1 ppm or less: Any supplied-air respirator with a full facepiece, helmet, or hood or any self-contained breathing apparatus with a full facepiece. A type C supplied air respirator operated in a pressure-demand or other positive pressure or continuous flow mode. 20 ppm or less: A type C supplied-air respirator with a full facepiece operated in pressure-demand or other positive pressure mode or with a full facepiece, helmet, or hood operated in continuous-flow mode. Greater than 20 ppm or entry and escape from unknown concentrations: Self-contained breathing apparatus with a full facepiece operated in a pressure-demand or other positive pressure mode or a combination respirator which includes a type C supplied-air respirator with a full facepiece operated in pressure-demand or other positive pressure or continuous-flow mode and an auxiliary self-contained breathing apparatus operated in pressure-demand or other positive pressure mode. Escape: Any escape self-contained breathing apparatus. /Methyl isocyanate/

Persons involved in fighting fires should wear a self-contained breathing apparatus with a full facepiece operated in a pressure-demand or other positive pressure mode. ... /Methyl isocyanate/

IDENTIFICATION AND USE: This chemical is a gray to brown powder which is soluble in ketones and esters. It is used in polymers and adhesive systems, as a high strength backbone or cross linking intermediate. HUMAN EXPOSURE AND TOXICITY: Isocyanates are irritating to the skin and the mucous membranes, Skin conditions range from localized itching to wide spread eczema. Eye affections are less common and lacrimation is often found, conjunctivitis is rare. Respiratory system effects can be severe. ANIMAL STUDIES: Limited evidence of carcinogenicity in animals. Groups of male and female B6C3F1 mice, six weeks old were given dietary concentrations of this chemical for 78 weeks followed by a basal diet for a further 25 weeks. There was no significant difference in treated and control animals. There was no increased incidence of tumors in treated animals. Groups of male and female Fischer 344/N rats, six weeks of age received the chemical by gavage for 22 weeks. Animals were subsequently fed a basal diet for 22 weeks. A significant increase in combined incidence of leukemias and malignant lymphomas was observed. Increased incidence of various skin tumors was also noted on the head, back and inguinal areas in males and females. Increased incidences of Zymbal gland tumors was observed. Levels of Evidence of Carcinogenicity: Male Rats: Positive; Female Rats: Positive; Male Mice: Negative; Female Mice: Negative.

LD50 Mouse iv 180 mg/kg

A bioassay for the possible carcinogenicity of 3,3'-dimethoxybenzidine-4,4'-diisocyanate was conducted using Fischer 344 rats and B6C3F1 mice. 3,3'-Dimethoxybenzidine-4,4'-diisocyanate was administered, at either of two concentrations, to groups of 50 male and 50 female animals of each species, with the exception of 49 high dose female rats. The compound was administered in the feed with the exception of the first 22 weeks of the rat bioassay, when it was administered by gavage. Twenty animals of each sex and species were placed on test as controls. During intubation the high and low dosages were 3,000 and 1,500 mg/kg, respectively, while the high and low concentrations administered in the feed to both rats and mice were 44,000 and 22,000 ppm, respectively. The compound was administered for a period of 78 weeks, followed by an observation period of 26 weeks for rats and 25 weeks for mice. There was a significant positive association between the administration of 3,3'-dimethoxybenzidine-4,4'-diisocyanate and mortality in male and female rats, but not in male or female mice. ... Under the conditions of this bioassay, administration of 3,3'-dimethoxybenzidine-4,4'-diisocyanate was carcinogenic to Fischer 344 rats, causing neoplasms of the skin (excluding skin of the ear) in males, endometrial stromal polyps in females, and leukemia and malignant lymphoma in both sexes. The compound was also associated with the development of a combination of squamous cell carcinomas and sebaceous adenocarcinomas of the Zymbal's gland and skin of the ear in rats of both sexes. There was no evidence of the carcinogenicity of the compound in B6C3F1 mice. Levels of Evidence of Carcinogenicity: Male Rats: Positive; Female Rats: Positive; Male Mice: Negative; Female Mice: Negative.

SYMPTOMS: Symptoms of exposure to this chemical may include skin irritation. ACUTE/CHRONIC HAZARDS: This compound is toxic by inhalation (at high temperatures) and ingestion. It is a skin irritant. When heated to decomposition it emits toxic fumes of nitrogen oxides. (NTP, 1992)

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. SKIN: IMMEDIATELY flood affected skin with water while removing and isolating all contaminated clothing. Gently wash all affected skin areas thoroughly with soap and water. IMMEDIATELY call a hospital or poison control center even if no symptoms (such as redness or irritation) develop. IMMEDIATELY transport the victim to a hospital for treatment after washing the affected areas. INHALATION: IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. IMMEDIATELY call a physician and be prepared to transport the victim to a hospital even if no symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop. Provide proper respiratory protection to rescuers entering an unknown atmosphere. Whenever possible, Self-Contained Breathing Apparatus (SCBA) should be used; if not available, use a level of protection greater than or equal to that advised under Protective Clothing. INGESTION: DO NOT INDUCE VOMITING. If the victim is conscious and not convulsing, give 1 or 2 glasses of water to dilute the chemical and IMMEDIATELY call a hospital or poison control center. Be prepared to transport the victim to a hospital if advised by a physician. If the victim is convulsing or unconscious, do not give anything by mouth, ensure that the victim's airway is open and lay the victim on his/her side with the head lower than the body. DO NOT INDUCE VOMITING. IMMEDIATELY transport the victim to a hospital. OTHER: Since this chemical is a known or suspected carcinogen you should contact a physician for advice regarding the possible long term health effects and potential recommendation for medical monitoring. Recommendations from the physician will depend upon the specific compound, its chemical, physical and toxicity properties, the exposure level, length of exposure, and the route of exposure. (NTP, 1992)

Noncardiogenic pulmonary edema and bronchospasm are the most immediate serious clinical consequences of isocyanate exposure. Markedly symptomatic patients should receive oxygen, ventilatory support, and an intravenous line. Treatment for asthma includes inhaled sympathomimetics (salbutamol, metaproterenol), intravenous theophylline, parenteral sympathomimetics (epinephrine, terbutaline), and steroids. /Isocyanates/|Most treatment is symptomatic. Mydriatics, systemic analgesics, and topical antibiotics (Sulamyd) may be used for corneal abrasions. There is no effective therapy for sensitized workers, and these people should be moved to a work site devoid of exposure to isocyanates. /Isocyanates/

Isocyanates are irritating to the skin and the mucous membranes, the skin conditions ranging from localized itching to more or less widespread eczema. Eye affections are less common and, although lacrimation is often found, conjunctivitis is rare. The commonest and most serious troubles, however, are those affecting the respiratory systems. /Isocyanates/

The US National Cancer Institute has characterized 3,3'- dimethoxybenzidine-4,4'diisocyanate as an experimental chemical with possible uses in coatings, gaskets, and shock absorbers.

Concentrations of the aerosol were monitored by collection on No. 42 Whatman filter paper, eluting with carbon tetrachloride and analysing by IR spectroscopy or by collecting in an absorbing solution, developing a color, and measuring colorimetrically.