3,3'-Dichlorobenzidine dihydrochloride

H312 (100%): Harmful in contact with skin [Warning Acute toxicity, dermal]

H317 (100%): May cause an allergic skin reaction [Warning Sensitization, Skin]

H350 (100%): May cause cancer [Danger Carcinogenicity]

H400 (29.5%): Very toxic to aquatic life [Warning Hazardous to the aquatic environment, acute hazard]

H410 (33.3%): Very toxic to aquatic life with long lasting effects [Warning Hazardous to the aquatic environment, long-term hazard]

H411 (66.7%): Toxic to aquatic life with long lasting effects [Hazardous to the aquatic environment, long-term hazard]

P203, P261, P272, P273, P280, P302+P352, P317, P318, P321, P333+P317, P362+P364, P391, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 156 reports by companies from 7 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Information may vary between notifications depending on impurities, additives, and other factors. The percentage value in parenthesis indicates the notified classification ratio from companies that provide hazard codes. Only hazard codes with percentage values above 10% are shown. For more detailed information, please visit ECHA C&L website.

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]

H341: Suspected of causing genetic defects [Warning Germ cell mutagenicity]

H351: Suspected of causing cancer [Warning Carcinogenicity]

P203, P261, P264+P265, P271, P280, P304+P340, P305+P354+P338, P317, P318, P319, P403+P233, P405, and P501 (click each P-code to see the statement)

H303: May be harmful if swallowed [Warning Acute toxicity, oral]

H350: May cause cancer [Danger Carcinogenicity]

P203, P264+P265, P280, P301+P317, P305+P354+P338, P317, P318, P405, and P501 (click each P-code to see the statement)

H319: Causes serious eye irritation [Warning Serious eye damage/eye irritation]

P203, P264+P265, P280, P305+P351+P338, P318, P337+P317, P405, and P501 (click each P-code to see the statement)

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)

Fires involving this compound should be controlled with a dry chemical, carbon dioxide or Halon extinguisher. (NTP, 1992)

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]:

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)

USE OF SODIUM HYPOCHLORITE BLEACH SOLUTION TO DECONTAMINATE 3,3'-DICHLOROBENZIDINE (DCB) WAS PARTIALLY EFFECTIVE. AN AQUEOUS SOLUTION OF 5% TETRAPOTASSIUM PYROPHOSPHATE AND 10% SODIUM ETHYL HEXYL SULFATE WHEN BLENDED IN A JET SPRAYER EFFECTIVELY REMOVED DCB FROM THE WORK AREA (90-99% REDUCTION). ONCE REMOVED FROM THE WORKSITE AND COLLECTED IN A CENTRAL LOCATION, IT WAS THEN DETERMINED THAT THE DIAZOTIZATION REACTION (THE ADDITION OF SO4, ICE AND NaNO3) OCCURRED TO ELIMINATE ANY DETECTABLE DCB FROM THE WASHINGS. /3,3'-DICHLOROBENZIDINE/

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.

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.

Incineration: 1500 °F, 0.5 sec for primary combustion; 2200 °F, 1.0 sec for secondary combustion. The formation of elemental chlorine can be prevented through injection of steam or methane into the combustion process. NOx may be abated through the use of thermal or catalytic devices.

PRECAUTIONS FOR "CARCINOGENS": There is no universal method of disposal that has been proved satisfactory for all carcinogenic compounds & specific methods of chem destruction ... published have not been tested on all kinds of carcinogen-containing waste. ... summary of avail methods & recommendations ... /given/ must be treated as guide only.

PRECAUTIONS FOR "CARCINOGENS": Total destruction ... by incineration may be only feasiable method for disposal of contaminated laboratory waste from biological expt. However, not all incinerators are suitable. ... Most efficient type ... is probably the gas-fired type, in which a first-stage combustion with a less than stoichiometric air:fuel ratio is followed by a second stage with excess air. Some ... are designed to accept ... aqueous & organic-solvent solutions, otherwise it is necessary ... to absorb soln onto suitable combustible material, such as sawdust. Alternatively, chem destruction may be used, esp when small quantities ... are to be destroyed in laboratory.

For more Disposal Methods (Complete) data for 3,3'-DICHLOROBENZIDINE DIHYDROCHLORIDE (6 total), please visit the HSDB record page.

Regulations in USA concerning 3,3'-dichlorobenzidine & its salts designate strict procedures to avoid worker contact: Mixtures containing 1.0% or more 3,3'-dichlorobenzidine & its salts must be maintained in isolated or closed systems, employees must observe special personal hygiene rules, & certain procedures must be followed for movement of the material & in case of accidental spills & emergencies ...

Employees working with 3,3'-dichlorobenzidine (or its salts) within an isolated system, such as a "glove box" shall wash their hands and arms upon completion of the assigned task and before engaging in other activities not associated with the isolated system.

On exit from a regulated area, employees should shower and change ... clothes, leaving protective clothing & equipment at the point of exit to be placed in ... /designated/ containers at the end of the work shift for decontamination or disposal.

Storage or consumption of food, storage or use of containers of beverages, storage or application of cosmetics, smoking, storage of smoking materials, tobacco products or other products for chewing, and the chewing of such products are prohibited in regulated areas.

For more Preventive Measures (Complete) data for 3,3'-DICHLOROBENZIDINE DIHYDROCHLORIDE (18 total), please visit the HSDB record page.

SMALL SPILLS AND LEAKAGE: Should a spill occur while you are handling this chemical, FIRST REMOVE ALL SOURCES OF IGNITION, then you should dampen the solid spill material with ethanol and transfer the dampened material to a suitable container. Use absorbent paper dampened with ethanol to pick up any remaining material. Seal the absorbent paper, and any of your clothes, which may be contaminated, in a vapor-tight plastic bag for eventual disposal. Solvent wash all contaminated surfaces with ethanol followed by washing with a soap and water solution. Do not reenter the contaminated area until the Safety Officer (or other responsible person) has verified that the area has been properly cleaned.

STORAGE PRECAUTIONS: You should protect this chemical from exposure to light. Keep the container tightly closed under an inert atmosphere, and store under refrigerated temperatures. (NTP, 1992)

Store in cool, dry place. Protection from light and air is recommended for long term storage. /Chemical Carcinogens/

PRECAUTIONS FOR "CARCINOGENS": Storage site should be as close as /possible/ to lab in which carcinogens are to be used, so that only small quantities required for ... expt need to be carried. Carcinogens should be kept in only one section of cupboard, an explosion-proof refrigerator or freezer (depending on chemicophysical properties ...) that bears appropriate label. An inventory ... should be kept, showing quantity of carcinogen & date it was acquired ... Facilities for dispensing ... should be contiguous to storage area.

NIOSH considers 3,3'-dichlorobenzidine to be a potential occupational carcinogen. /3,3'-Dichlorobenzidine (and its salts)/

Exposure by all routes should be carefully controlled to levels as low as possible. Skin. /3,3'-Dichlorobenzidine/

A3; Confirmed animal carcinogen with unknown relevance to humans. /3,3'-Dichlorobenzidine/

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)

Full body protective clothing and gloves should be employed in handling operations. Full face supplied air respirators of continuous flow or pressure demand type should also be used.

PRECAUTIONS FOR "CARCINOGENS": ... dispensers of liq detergent ... Safety pipettes ... for all pipetting. ... In animal laboratory ... protective suits (preferably disposable, one-piece & close-fitting at ankles & wrists), gloves, hair covering & overshoes. ... In chemical laboratory, gloves & gowns should always be worn ... however, gloves should not be assumed to provide full protection. Carefully fitted masks or respirators ... when working with particulates or gases, & disposable plastic aprons ... gowns ... /should be/ of distinctive color ... .

Wear appropriate personal protective clothing to prevent skin contact. /3,3'-Dichlorobenzidine (and its salts)/

Wear appropriate eye protection to prevent eye contact. /3,3'-Dichlorobenzidine (and its salts)/

For more Personal Protective Equipment (PPE) (Complete) data for 3,3'-DICHLOROBENZIDINE DIHYDROCHLORIDE (7 total), please visit the HSDB record page.

3,3'-dichlorobenzidine dihydrochloride is a light tan powder. (NTP, 1992)

CBI; Wet Solid

White to light-gray solid; [HSDB] Light tan solid; [CAMEO]

White crystals; white to light-gray powder

mild odor

less than 1 mg/mL at 70.7 °F (NTP, 1992)

Readily sol in alcohol; slightly soluble in water

When heated to decomp it emits very toxic fumes of /hydrogen chloride & nitrogen oxides./

Nitrogen Compounds -> Benzidine and Derivatives

Carcinogens

Insoluble in water.

Salts, Acidic

Aryl Halides

3,3'-DICHLOROBENZIDINE DIHYDROCHLORIDE reacts as a weak acid. May react vigorously with strong oxidizing agents. May generate flammable gases with strong reducing agents.

CLASSIFICATION: B2; probable human carcinogen. BASIS FOR CLASSIFICATION: Based on statistically significantly increased tumor incidence in rats, mice and dogs. Additional support is provided by positive evidence of genotoxicity and structural relationship to the known human bladder carcinogen benzidine. HUMAN CARCINOGENICITY DATA: Inadequate. ANIMAL CARCINOGENICITY DATA: Sufficient. /3,3'-Dichlorobenzidine/

Inadequate evidence of carcinogenicity in humans. Sufficient evidence of carcinogenicity in animals. OVERALL EVALUATION: Group 2B: The agent is possibly carcinogenic to humans. /3,3'-Dichlorobenzidine/

A3; Confirmed animal carcinogen with unknown relevance to humans. /3,3'-Dichlorobenzidine/

3,3'-Dichlorobenzidine Dihydrochloride: reasonably anticipated to be a human carcinogen.

Occupational hepatotoxin - Secondary hepatotoxins: the potential for toxic effect in the occupational setting is based on cases of poisoning by human ingestion or animal experimentation.

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

NTP Carcinogen - Reasonably anticipated to be a human carcinogen.

LD50 Rat (Sprague-Dawley) oral 3.82 g/kg

Preplacement and periodic exam should include history of exposure to other carcinogens, smoking, alcohol, medication, and family history. The skin, lung, kidney, bladder, and liver should be evaluated; sputum or urinary cytology may be helpful.

PRECAUTIONS FOR "CARCINOGENS": ... In relation specifically to cancer hazards, there are at present no health monitoring methods that may ensure the early detection of preneoplastic lesions or lesions which may prelude them. Whenever medical surveillance is indicated, in particular when exposure to a carcinogen has occurred, ad hoc decisions should be taken concerning additional tests that might become useful or mandatory.

... PRONOUNCED STERNUTATORY /SNEEZING/ EFFECT.

Gastrointestinal upset was one of the symptoms reported by employees who worked with 3,3'-dichlorobenzidine dihydrochloride (dihydro salt of 3,3'-dichlorobenzidine) ... . However, there is no conclusive evidence that the GI effects, or other symptoms reported by employees, resulted specifically from inhalation of 3,3'-dichlorobenzidine dihydrochloride.

DERMAL EXPOSURE TO 3,3'-DICHLOROBENZIDINE BASE HAS CAUSED DERMATITIS IN DYE WORKERS. /3,3'-DICHLOROBENZIDINE/

3,3'-DICHLOROBENZIDINE DIHYDROCHLORIDE AT 50 UG/PLATE & 100 UG/PLATE, WAS MODERATELY MUTAGENIC IN SALMONELLA TYPHIMURIUM STRAINS TA98 & TA100 WITHOUT THE MAMMALIAN ENZYME PREPARATION; HOWEVER, THE MUTAGENICITY WAS INCREASED MARKEDLY WHEN THE S-9 FRACTION WAS ADDED TO THE REACTION MIXTURES. MAMMALIAN ENZYME PREPARATIONS (S-9 FRACTIONS) WERE PREPARED FROM UNINDUCED ADULT MALE BALB/C MICE.

The dihydrochloride salt was shown to be a severe eye irritant as opposed to the free base; the Draize test of rabbits produced erythema, chemoses, & corneal opacity with an average score of 84 out of 110 maximally attainable.

ALL ANIMAL TESTS OF ACUTE & CHRONIC TOXICITY INDICATE BOTH BASE & /DIHYDROCHLORIDE/ SALT TO BE LOW; THE RAT ORAL LD50 WAS ABOUT 7 G/KG; THAT OF THE HYDROCHLORIDE SALT, 3.82 G/KG; FOR THE RABBIT, BETWEEN 0.5 & 1 G/KG. GI CONGESTION & HEMORRHAGING WERE CHIEF AUTOPSY FINDINGS. NINE OF 14 RATS SURVIVED MORE THAN 288 DAYS OF INGESTING 700 MG/KG OF BASE IN OLIVE OIL, 5 DAYS/WK. LIVER DAMAGE & ONE TUMOR WERE ... /FOUND/.

A GROUP OF 20 FEMALE SPRAGUE-DAWLEY RATS (40 DAYS OF AGE) WERE GIVEN 10 DOSES OF 3,3'-DICHLOROBENZIDINE DIHYDROCHLORIDE (PURITY & IMPURITIES UNSPECIFIED) EVERY THREE DAYS BY GASTRIC INTUBATION (TOTAL DOSE, 300 MG/RAT, WHICH WAS THE MAXIMUM TOLERATED DOSE). THE OBSERVATION PERIOD WAS NINE MONTHS, WHEN THE SURVIVING ANIMALS WERE KILLED. NO MAMMARY TUMORS WERE OBSERVED IN 15 RATS AUTOPSIED, WHILE 100% OF THE POSITIVE CONTROL GROUP (TREATED WITH 7,12-DIMETHYLBENZ(A)ANTHRACENE) & 3% OF ANIMALS TREATED WITH SESAME OIL ONLY HAD MAMMARY TUMORS ... .

For more Non-Human Toxicity Excerpts (Complete) data for 3,3'-DICHLOROBENZIDINE DIHYDROCHLORIDE (7 total), please visit the HSDB record page.

Inhalation & probably percutaneous absorption.

OCCUPATIONAL EXPOSURE TO 3,3'-DICHLOROBENZIDINE DIHYDROCHLORIDE HAS & PROBABLY STILL DOES OCCUR DURING ITS MANUFACTURE & CONVERSION TO DERIVED PIGMENTS. RUBBER WORKERS WERE FORMERLY & MAY STILL BE EXPOSED TO 3,3'-DICHLOROBENZIDINE USED FOR CURING POLYURETHANE ELASTOMERS.

Processes in which dried dye is handled have the greatest potential for employee exposure during the manufacture or repackaging of benzidine-based dyes. ... During use of benzidine-based dyes, the greatest potential for exposure would be expected to be among dye-weighers who handle dry powders. /Benzidine-based dyes/

Inhalation & probably percutaneous absorption.

OCCUPATIONAL EXPOSURE TO 3,3'-DICHLOROBENZIDINE DIHYDROCHLORIDE HAS & PROBABLY STILL DOES OCCUR DURING ITS MANUFACTURE & CONVERSION TO DERIVED PIGMENTS. RUBBER WORKERS WERE FORMERLY & MAY STILL BE EXPOSED TO 3,3'-DICHLOROBENZIDINE USED FOR CURING POLYURETHANE ELASTOMERS.

Processes in which dried dye is handled have the greatest potential for employee exposure during the manufacture or repackaging of benzidine-based dyes. ... During use of benzidine-based dyes, the greatest potential for exposure would be expected to be among dye-weighers who handle dry powders. /Benzidine-based dyes/

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.

Incineration: 1500 °F, 0.5 sec for primary combustion; 2200 °F, 1.0 sec for secondary combustion. The formation of elemental chlorine can be prevented through injection of steam or methane into the combustion process. NOx may be abated through the use of thermal or catalytic devices.

PRECAUTIONS FOR "CARCINOGENS": There is no universal method of disposal that has been proved satisfactory for all carcinogenic compounds & specific methods of chem destruction ... published have not been tested on all kinds of carcinogen-containing waste. ... summary of avail methods & recommendations ... /given/ must be treated as guide only.

PRECAUTIONS FOR "CARCINOGENS": Total destruction ... by incineration may be only feasiable method for disposal of contaminated laboratory waste from biological expt. However, not all incinerators are suitable. ... Most efficient type ... is probably the gas-fired type, in which a first-stage combustion with a less than stoichiometric air:fuel ratio is followed by a second stage with excess air. Some ... are designed to accept ... aqueous & organic-solvent solutions, otherwise it is necessary ... to absorb soln onto suitable combustible material, such as sawdust. Alternatively, chem destruction may be used, esp when small quantities ... are to be destroyed in laboratory.

For more Disposal Methods (Complete) data for 3,3'-DICHLOROBENZIDINE DIHYDROCHLORIDE (6 total), please visit the HSDB record page.