Hydrazobenzene

H302: Harmful if swallowed [Warning Acute toxicity, oral]

H350: May cause cancer [Danger Carcinogenicity]

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

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

P203, P264, P270, P273, P280, P301+P317, P318, P330, P391, P405, and P501 (click each P-code to see the statement)

H302 (100%): Harmful if swallowed [Warning Acute toxicity, oral]

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

H400 (98.8%): Very toxic to aquatic life [Warning Hazardous to the aquatic environment, acute hazard]

H410 (100%): Very toxic to aquatic life with long lasting effects [Warning Hazardous to the aquatic environment, long-term hazard]

Aggregated GHS information provided per 86 reports by companies from 6 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.

H412: Harmful to aquatic life with long lasting effects [Hazardous to the aquatic environment, long-term hazard]

P203, P273, P280, P318, P391, P405, and P501 (click each P-code to see the statement)

H301: Toxic if swallowed [Danger Acute toxicity, oral]

H351: Suspected of causing cancer [Warning Carcinogenicity]

H373: May causes damage to organs through prolonged or repeated exposure [Warning Specific target organ toxicity, repeated exposure]

P203, P260, P264, P270, P280, P301+P316, P318, P319, P321, P330, P405, and P501 (click each P-code to see the statement)

Fresh air, rest.

Remove contaminated clothes. Rinse and then wash skin with water and soap.

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

Rinse mouth. Refer for medical attention .

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. If symptoms such as redness or irritation develop, IMMEDIATELY call a physician and be prepared to transport the victim to a hospital for treatment.

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 material can be controlled with a dry chemical, carbon dioxide or Halon extinguisher. A water spray may also be used. (NTP, 1992)

Use water spray, powder, foam, carbon dioxide.

Excerpt from ERG Guide 154 [Substances - Toxic and/or Corrosive (Non-Combustible)]:

IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids.

SPILL: Increase the immediate precautionary measure distance, in the downwind direction, as necessary.

FIRE: If tank, rail tank car or highway tank is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2024)

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

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/

Cleavage of hydrazine as a method of preventing environmental contamination was investigated. 1,1-Diethylhydrazine, ...Hydrazine compounds were dissolved in a solution of potassium-hydroxide or of methanol and potassium-hydroxide, followed by addition of an aluminum/nickel alloy. The reaction mixture was injected into a gas chromatography equipped with a flame ionization detector. The quantity of amine present was determined. ...Residual hydrazine could not be detected in any of the reactions after 24 hr of exposure to the reductant. Amines corresponding to the reduced hydrazine were the only products detected by gas chromatography. Yields ranged from 73 to 104%, with a detection limit of 1% of the theoretical yield. No benzidine was found from reduction of 1,2-diphenylhydrazine. /It was/ concluded that the procedures provide a reliable, efficient, one step approach to conversion of potentially carcinogenic hydrazines to innocuous products in laboratory wastes or in the environment.

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number U109, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.

1,2-Diphenylhydrazine is a potential candidate for rotary kiln incineration with a temperature range of 820 to 1600 °C and residence times of seconds for liquids and gases; hours for solids. Also a potential candidate for fluidized bed incineration with a temperature range of 450 to 980 °C and residence times of seconds for liquids and gases; longer for solids.

Physical chemical treatment (coagulation/flocculation followed by sedimentation), with hauling of the sludge. ... /Another method is/ wet air oxidation, using a starting concentration of 5 g/l hydrazobenzene, 99.98% of the 1,2-diphenylhydrazine was destroyed in 1 hr at 275 °C and at 320 °C.

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. /Chemical Carcinogens/

For more Disposal Methods (Complete) data for 1,2-DIPHENYLHYDRAZINE (10 total), please visit the HSDB record page.

PRECAUTIONS FOR "CARCINOGENS": Smoking, drinking, eating, storage of food or of food & beverage containers or utensils, & the application of cosmetics should be prohibited in any laboratory. All personnel should remove gloves, if worn, after completion of procedures in which carcinogens have been used. They should ... wash ... hands, preferably using dispensers of liq detergent, & rinse ... thoroughly. Consideration should be given to appropriate methods for cleaning the skin, depending on nature of the contaminant. No standard procedure can be recommended, but the use of organic solvents should be avoided. Safety pipettes should be used for all pipetting. /Chemical Carcinogens/

PRECAUTIONS FOR "CARCINOGENS": In animal laboratory, personnel should remove their outdoor clothes & wear protective suits (preferably disposable, one piece & close fitting at ankles & wrists), gloves, hair covering, & overshoes. ... clothing should be changed daily but ... discarded immediately if obvious contamination occurs ... /also,/ workers should shower immediately. In chemical laboratory, gloves & gowns should always be worn ... however, gloves should not be assumed to provide full protection. Carefully fitted masks or respirators may be necessary when working with particulates or gases, & disposable plastic aprons might provide addnl protection. If gowns are of distinctive color, this is a reminder that they should not be worn outside of lab. /Chemical Carcinogens/

PRECAUTIONS FOR "CARCINOGENS": ... Operations connected with synth & purification ... should be carried out under well-ventilated hood. Analytical procedures ... should be carried out with care & vapors evolved during ... procedures should be removed. ... Expert advice should be obtained before existing fume cupboards are used ... & when new fume cupboards are installed. It is desirable that there be means for decreasing the rate of air extraction, so that carcinogenic powders can be handled without ... powder being blown around the hood. Glove boxes should be kept under negative air pressure. Air changes should be adequate, so that concn of vapors of volatile carcinogens will not occur. /Chemical Carcinogens/

PRECAUTIONS FOR "CARCINOGENS": Vertical laminar flow biological safety cabinets may be used for containment of in vitro procedures ... provided that the exhaust air flow is sufficient to provide an inward air flow at the face opening of the cabinet, & contaminated air plenums that are under positive pressure are leak tight. Horizontal laminar flow hoods or safety cabinets, where filtered air is blown across the working area towards the operator, should never be used ... Each cabinet or fume cupboard to be used ... should be tested before work is begun (eg, with fume bomb) & label fixed to it, giving date of test & avg air flow measured. This test should be repeated periodically & after any structural changes. /Chemical Carcinogens/

For more Preventive Measures (Complete) data for 1,2-DIPHENYLHYDRAZINE (10 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 60-70% ethanol and transfer the dampened material to a suitable container. Use absorbent paper dampened with 60-70% 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 60-70% 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)

Separated from food and feedstuffs. Store in an area without drain or sewer access.

PRECAUTIONS FOR "CARCINOGENS": Storage site should be as close as practicable 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. /Chemical Carcinogens/

2.9 [mg/m3]

32 [mg/m3]

190 [mg/m3]

carcinogen category: 2

A harmful concentration of airborne particles can be reached quickly when dispersed.

May cause mechanical irritation.

This substance is probably carcinogenic to humans.

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)

PRECAUTIONS FOR "CARCINOGENS": ... Dispensers of liq detergent /should be available./ ... Safety pipettes should be used for all pipetting. ... In animal laboratory, personnel should ... wear 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 may be necessary when working with particulates or gases, & disposable plastic aprons might provide addnl protection. ... Gowns ... /should be/ of distinctive color, this is a reminder that they are not to be worn outside the laboratory. /Chemical Carcinogens/

All systems or equipment containing the hydrazines shall be designed to minimize the possibility of vapor or aerosol inhalation, skin or eye contact, and spill or leaks; such as full face shields, goggles, and full body protection clothing, including gloves and boots.

... Vinyl coated hand protection, natural or reclaimed rubber protection, rubber aprons, and plastic eye and face protection ... used when working with small quantities. Where possibility of gross splashing exists, full protective clothing made of rubber, neoprene or vinyl-coated materials should be worn. For respiratory protection in situations where recommended tolerance limits ... exceeded, respiratory protective equipment such as approved canisters or a gas mask or self- contained breathing apparatus must be used. /Hydrazine and derivatives/

NO open flames.

See EFFECTS OF LONG-TERM OR REPEATED EXPOSURE. AVOID ALL CONTACT!

Use local exhaust or breathing protection.

Protective gloves. Protective clothing.

Wear safety spectacles or eye protection in combination with breathing protection.

Do not eat, drink, or smoke during work. Wash hands before eating.

Diphenylhydrazine appears as yellow crystals. Insoluble in water.

1,2-diphenylhydrazine appears as orange powder or a bright orange crystalline solid. (NTP, 1992)

Orange powder or a bright orange crystalline solid; [CAMEO]

WHITE-TO-YELLOW CRYSTALS.

Tablets from alcohol and ether

Colorless crystals

Decomposes (NTP, 1992)

293 °C at 760 mm Hg

293 °C @760 [mm Hg]

268 °F (NTP, 1992)

131 °C, decomposes

Decomposes at its melting point, into azobenzene and aniline.

Heat of fusion at melting point= 1.7630X10+7 J/kmol

less than 0.1 mg/mL at 64 °F (NTP, 1992)

Slightly sol in benzene, deuterated dimethyl sulfoxide; insol in acetic acid; very soluble in ethanol

In water, 221 mg/L at 25 °C

Solubility in water, g/100ml at 20 °C:

1.158 at 61 °F (NTP, 1992) - Denser than water; will sink

1.158 at 16 °C/4 °C

1.16 g/cm³

1.158 @ 16°C

0.00044 [mmHg]

4.4X10-4 mm Hg at 25 °C

log Kow= 2.94

Henry's Law constant = 4.8X10-7 atm-cu m/mol at 25 °C /Estimated/

Hydrazobenzene (10 ug/L) in dilute aqueous solution was found to be unstable with less than 10% remaining for longer than one day of preservation (in the dark) under any of the conditions tested (ie, room temperature or 4 °C at pH 2,7, or 10 and with or without chlorine).

Autooxidizes in air

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

Decomposes, at its melting point, into azobenzene and aniline.

125-131 °C

pKa = -0.65 /Estimated/

Heat of fusion: 17,645 J/mole

Hydroxyl radical reaction rate constant = 8.5X10-11 cu cm/molec-sec at 25 °C /Estimated/

15N nuclear magnetic resonance spectrum

Chemical shift

Crystal structure

Formula unit

Fusion temperature

Magnetic anisotropy

Melting temperature

Insoluble in water.

This chemical oxidizes in air. It decomposes in acid solutions. Insoluble in water.

Amines, Phosphines, and Pyridines

Azo, Diazo, Azido, Hydrazine, and Azide Compounds

Hydrocarbons, Aromatic

Reducing Agents, Strong

Toxic gases may be formed by mixing DIPHENYLHYDRAZINE with acids, aldehydes, amides, carbamates, cyanides, inorganic fluorides, halogenated organics, isocyanates, ketones, metals, nitrides, peroxides, phenols, epoxides, acyl halides, and strong oxidizing or reducing agents. Flammable gases are formed by mixing materials in this group with alkali metals. Explosive combination can occur with strong oxidizing agents, metal salts, peroxides, and sulfides.

1,2-DIPHENYLHYDRAZINE is a mild reducing agent. Incompatible with strong oxidizing agents, strong acids, acid chlorides and acid anhydrides. Interaction with perchloryl fluoride in the presence of a dilutent below 32 °F has caused separation of explosive solids. Is readily oxidized by nitric acid, silver nitrate or permanganate. Is reduced under alkaline conditions (NTP, 1992).

CDC-ATSDR Toxicological Profile

Two of the known metabolites, aniline and benzidine, may contribute to the toxicity and/or carcinogenicity of 1,2-diphenylhydrazine. Nonneoplastic liver lesions, hepatocellular carcinomas and/or neoplastic liver nodules indicate that the liver is a target of 1,2-diphenylhydrazine toxicity. As aniline and other aromatic amino metabolites of 1,2-diphenylhydrazine (e.g., aminophenols) are methemoglobinforming compounds by either oral or inhalation routes of exposure, it is possible that 1,2-diphenylhydrazine may cause methemoglobinemia in humans. (L463)

1,2-Diphenylhydrazine

Semi-Volatile Organic Compound (SVOC)

Smith, C.D. and Nowell, L.H., 2024. Health-Based Screening Levels for evaluating water-quality data (3rd ed.). DOI:10.5066/F71C1TWP

CLASSIFICATION: B2; probable human carcinogen. BASIS FOR CLASSIFICATION: Positive results of studies in both rats and mice form the basis for this classification. Two apparently negative studies lack information on compound purity, experimental design, and statistical treatment. HUMAN CARCINOGENICITY DATA: None.

Hydrazobenzene: reasonably anticipated to be a human carcinogen.

Group 2B: Possibly carcinogenic to humans

Volume 130: (2022) 1,1,1-Trichloroethane and Four Other Industrial Chemicals

2022 online

Hydrazobenzene

TR-092: Bioassay of Hydrazobenzene for Possible Carcinogenicity (CASRN 122-66-7) (1978 )

04/26/78

Clear Evidence

No Evidence

Under the conditions of this bioassay, hydrazobenzene was carcinogenic to Fischer 344 rats of both sexes, causing increased incidences of hepatocellular carcinoma and Zymbal's gland squamous-cell neoplasms in male rats, neoplastic nodules of the liver in female rats, and mammary adenocarcinomas in female rats. Hydrazobenzene was also carcinogenic to female B6C3F1 mice, causing an increased incidence of hepatocellular carcinomas. The compound was not carcinogenic to male B6C3F1 mice.

Not listed by IARC. Benzidine, a metabolite of 1,2-diphenylhydrazine, is carcinogenic to humans (Group 1). Aniline, another metabolite, is not classifiable as to its carcinogenicity to humans (Group 3). (L135)

Nonneoplastic liver lesions, hepatocellular carcinomas and/or neoplastic liver nodules; seizures and coma. (L463)

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

Redness.

Irritatinon to the eyes, nose and respiratory system, depending on the route of exposure. Cough, redness of the exposed surface. (L463)

Cancer, Hepatic (Liver)

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.

Methemoglobinemia - The presence of increased methemoglobin in the blood; the compound is classified as secondary toxic effect

IARC Carcinogen - Class 3: Chemicals are not classifiable by the International Agency for Research on Cancer.

NTP Carcinogen - Reasonably anticipated to be a human carcinogen.

IRIS Current

ATSDR Final

LD50: 959 mg/kg (Oral, Rat) (L463)

Consider gastric lavage after ingestion of a potentially life-threatening amount of poison if it can be performed soon after ingestion. Following inhalation, move patient to fresh air. Monitor for respiratory distress. If cough or difficulty breathing develops, evaluate for respiratory tract irritation, bronchitis, or pneumonitis. Administer oxygen and assist ventilation as required. Treat bronchospasm with inhaled beta2 agonist and oral or parenteral corticosteroids. Irrigate exposed eyes with copious amounts of room temperature water for at least 15 minutes. If the exposure occurs through dermal contact remove contaminated clothing and wash exposed area thoroughly with soap and water. A physician may need to examine the area if irritation or pain persists. (T36)

Specific treatment for exposure consists of thorough washing of all exposed skin areas with soap and water, copious irrigation of the eyes, and prompt removal of the patient from the source of exposure. /Hydrazines/

After inhalation, observation for progressive respiratory distress is necessary. Chest X-ray and arterial blood gases should be monitored. Administration of oxygen, intubation, and assisted ventilation may become necessary. Pneumonia and bronchitis need to be excluded. /Hydrazines/

Pyridoxine may be antidotal. Seizures should be controlled with diazepam, phenytoin, or phenobarbital. Blood sugar levels should be monitored for severe hypoglycemia, which may appear with or without preceding significant hyperglycemia. The patient should be observed for evidence of intravascular hemolysis, methemoglobinemia, and consequent deterioration of renal function. Patients who are symptomatic or who demonstrate a methemoglobin level greater than 30 per cent should be treated with methylene blue 1 to 2 mg per kg slowly IV every 4 hours as needed. Improvement is dramatic if diagnosis is correct. Liver function should be monitored because hydrazines are known hepatotoxins. /Hydrazines/

Elimination is enhanced by forced diuresis and acidification of the urine. Hemodialysis and peritoneal dialysis should be effective, but insufficient human data exist on the use of these modalities. Treatment is otherwise symptomatic and supportive. /Hydrazines/

For more Antidote and Emergency Treatment (Complete) data for 1,2-DIPHENYLHYDRAZINE (6 total), please visit the HSDB record page.

PRECAUTIONS FOR "CARCINOGENS": Whenever medical surveillance is indicated, in particular when exposure to a carcinogen has occurred, ad hoc decisions should be taken concerning ... /cytogenetic and/or other/ tests that might become useful or mandatory. /Chemical Carcinogens/

Placement medical examinations shall include at least: comprehensive medical and work histories; comprehensive physical examination; specific clinical tests including complete and differential blood count; liver function tests including serum glutamic pyruvic transaminase (SGPT), urinalysis including specific gravity, glucose, protein, and microscopic examination, and a 14 x 17 inch posteroanterior chest roentenogram; a judgement of the worker's ability to use positive pressure respirators; and urobilinogen and serum bilirubin tests shall be considered by the responsible physician. Periodic examinations shall be made available at least annually to those working with hydrazines. /Hydrazines/

/HUMAN EXPOSURE STUDIES/ Examination of 194 employees in a plant manufacturing benzidine showed 20 cases of tumors in the urinary system after an exposure to 0.03-0.1 ug benzidine and 0.006-3000 ug hydrazobenzene/L of air for 8 years on the average. The highest rate of tumor incidence was between the 6th and 10th year of exposure.

/CASE REPORTS/ In the past, isolated cases of irritant cystitis with incontinence and hematuria have been seen on exposure to high concentrations of hydrazobenzene.

/LABORATORY ANIMALS: Acute Exposure/ Diphenyl hydrazine was shown to depress testicular DNA synthesis in mice when administered ip at a dose of 100 mg/kg.

LC50 Daphnia magna (water flea) 8.1 mg/L/24 hr /Conditions of bioassay not specified/

LC50 Daphnia magna (water flea) 4.1 mg/L/48 hr /Conditions of bioassay not specified/

LC50 Lepomis macrochirus (bluegill) 1.2 mg/L/24 hr (static bioassay, total water hardness 28-44 mg/L calcium carbonate, pH 6.7-7.4, oxygen concn 5.3-7.0 mg/L)

LC50 Lepomis macrochirus (bluegill) 0.27 mg/L/96 hr (static bioassay, total water hardness 28-44 mg/L calcium carbonate, pH 6.7-7.4, oxygen concn 5.3-7.0 mg/L)

LC50 Daphnia magna (cladoceran) static method 4,100 ug/L/96 hr

6.80e-01

2.90e+00

1.30e-02

5.60e-02

7.80e-02

2.50e-04

8.00e-01

2.20e-04

Volatile

6.80e+01

2.90e+02

1.30e+00

5.60e+00

7.80e+00

The substance is very toxic to aquatic organisms. Bioaccumulation of this chemical may occur in fish.

1,2-Diphenylhydrazine's production and use as a chemical intermediate may result in its release to the environment through various waste streams. It may also be produced in wastewater receiving azobenzene where conditions are reducing. If released to air, a vapor pressure of 4.4X10-4 mm Hg at 25 °C indicates that 1,2-diphenylhydrazine will exist in both the vapor and particulate phases in the ambient atmosphere. Vapor-phase 1,2-diphenylhydrazine is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals with an estimated half-life of about 5 hours. Particulate-phase 1,2-diphenylhydrazine may be physically removed from the air by wet and dry deposition. 1,2-Diphenylhydrazine absorbs light greater than 290 nm and may be susceptible to direct photolysis; however, the rate of this potential reaction is not known. If released to soil 1,2-diphenylhydrazine is expected to have low mobility based upon an estimated Koc of 950. Volatilization from moist soil surfaces is not expected to be an important fate process based upon an estimated Henry's Law constant of 4.8X10-7 atm-cu m/mole. 1,2-Diphenylhydrazine is not expected to volatilize from dry soil surfaces based on its vapor pressure. If released to water 1,2-diphenylhydrazine is expected to adsorb to suspended solids and sediment based on the estimated Koc value. Volatilization from water surfaces is not expected to be an important environmental fate process based on the estimated Henry's Law constant. 1,2-Diphenylhydrazine is rapidly oxidized to azobenzene in aerobic solutions and the reaction is catalyzed by common environmental cations such as copper(II) and iron(III). This reaction is reversible. Under oxidizing conditions (such as well aerated surface waters) the formation of azobenzene is favored, while under reducing conditions (such as anaerobic sediment), conversion back to 1,2-diphenylhydrazine is favored. Degradation of this compound may result from photolysis and possibly biodegradation, but these processes should be slow as compared with oxidation to azobenzene under aerobic conditions. A BCF value of 29 measured in fish and shellfish suggests that bioconcentration in aquatic organisms is low. Occupational exposure may occur through inhalation or dermal contact at workplaces where 1,2-diphenylhydrazine is produced or used. Phenylbutazone, a drug used for the treatment of inflammatory conditions such as arthritis and sulfinpyrazone, a drug used to treat gouty arthritis are synthesized from 1,2-diphenylhydrazine and have been shown to hydrolyze to 1,2-diphenylhydrazine. Therefore, low levels of exposure to 1,2-diphenylhydrazine may exist for patients using these anti-inflammatory drugs. However, this drug is primarily used as a veterinary medication and its current use in humans is unknown.(SRC)

1,2-Diphenylhydrazine's production and use as a chemical intermediate(1,2) may result in its release to the environment through various waste streams(SRC). It also may be produced in wastewater receiving azobenzene where conditions are reducing(3).

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 950(SRC), determined from a log Kow of 2.94(2)and a regression-derived equation(3), indicates that 1,2-diphenylhydrazine is expected to have low mobility in soil(SRC). Volatilization of 1,2-diphenylhydrazine from moist soil surfaces is not expected based upon an estimated Henry's Law constant of 4.8X10-7 atm-cu m/mole(SRC), derived from its vapor pressure, 4.4X10-4 mm Hg(4), and water solubility, 221 mg/L(5). Based on limited aqueous screening study data, 1,2-diphenylhydrazine is expected to biodegrade in soil under aerobic conditions (80% degradation in 7 days)(6). 1,2-Diphenylhydrazine, may also oxidize to azobenzene by air or cations in the soil(7).

AQUATIC FATE: 1,2-Diphenylhydrazine rearranges intramolecularly to benzidine in aq acid. Although the concn of aq acid that is necessary for this reaction is unlikely to be found in ambient surface waters, this rearrangement can proceed easily in presence of anionic micelles such as would be formed from commercial laundry detergents.

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 950(SRC), determined from a log Kow of 2.94(2) and a regression-derived equation(3), indicates that 1,2-diphenylhydrazine is expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is not expected(3) based upon an estimated Henry's Law constant of 4.8X10-7 atm-cu m/mole(SRC), derived from its vapor pressure, 4.4X10-4 mm Hg(4), and water solubility, 221 mg/L(5). According to a classification scheme(6), an average BCF of 29 measured in fish and shellfish(7), suggests that bioconcentration in aquatic organisms is low(SRC). 1,2-Diphenylhydrazine undergoes rapid reversible oxidation in solution in the presence of dissolved oxygen and environmentally common cations (e.g. copper(II) and Fe(III)) to azobenzene(8); thus conversion to azobenzene in well-aerated waters should be a major fate process for this compound(SRC). If the conditions of the water body become reducing, the azobenzene will revert to 1,2-diphenylhydrazine(8). Based on limited aqueous screening study data, 1,2-diphenylhydrazine is expected to biodegrade in water under aerobic conditions (80% degradation in 7 days)(9). 1,2-Diphenylhydrazine absorbs light >290 nm(10) and may be subject to direct photolysis in sunlit surface waters, but the rate of this potential reaction is not known.

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 1,2-diphenylhydrazine, which has a vapor pressure of 4.4X10-4 mm Hg at 25 °C(2), will exist in both the vapor and particulate phases in the ambient atmosphere. Vapor-phase 1,2-diphenylhydrazine 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 about 5 hours(SRC), from its rate constant of 8.5X10-11 cu cm/molecule-sec at 25 °C(SRC) derived using a structure estimation method(3). Particulate-phase 1,2-diphenylhydrazine may be physically removed from the air by wet and dry deposition(SRC). 1,2-Diphenylhydrazine absorbs light greater than 290 nm(4), and may be susceptible to direct photolysis; however, the rate of this potential reaction is not known(SRC).

1,2-Diphenylhydrazine is degraded by sludge microorganisms(1). Using a static screening test, 1,2-diphenylhydrazine was inoculated with domestic wastewater and incubated for 7 days followed by 3 weekly subcultures (totaling 28 days of incubation); degradation of 1,2-diphenylhydrazine at 5 mg/l was reported as 80, 73, 66, and 77% for the original, first, second, and third subculture. Degradation of 1,2-diphenylhydrazine at 10 mg/l was reported as 72, 55, 40, and 40% for the original, first, second, and third subculture(2). This pattern was believed to indicate a process of initially significant degradation with gradual adaptation followed by a deadaptive process(2).

Although 1,2-diphenylhydrazine absorbs UV radiation beyond 316 nm(1), UV photolysis in solutions or organic solvents yields only azobenzene when aerated and azobenzene and aniline under a nitrogen atmosphere(2). 1,2-Diphenylhydrazine is rapidly oxidized to azobenzene in aerobic solutions and the reaction is catalyzed by common environmental cations such as copper(II) and iron(III). The half-lives from the uncatalyzed and catalyzed reaction are 5.78 and 1.16 min, respectively, at pH 10(2). No rates were calculated at pH 7, although it was reported that this reaction proceeded at an observable rate even in acidic solution(2). This redox reaction is readily reversible, and therefore, the reaction may not lead to ultimate destruction but does provide a mechanism for environmental degradation via azobenzene(SRC). The latter chemical is decomposed by UV radiation(3). Under acidic conditions (pH 2 or less), 1,2-diphenylhydrazine may be transformed to benzidine(2). There is no data to suggest 1,2-diphenylhydrazine undergoes hydrolysis(2). The rate constant for the vapor-phase reaction of 1,2-diphenylhydrazine with photochemically-produced hydroxyl radicals has been estimated as 8.5X10-11 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(4). This corresponds to an atmospheric half-life of about 5 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(4).

The weighted average bioconcentration factor for 1,2-diphenylhydrazine was reported to be 29 for the edible portions of fish and shellfish consumed by Americans(1). According to a classification scheme(2), this BCF value suggests that bioconcentration in aquatic organisms is low(SRC)

The Koc of 1,2-diphenylhydrazine is estimated as approximately 950(SRC), using a measured log Kow of 2.94(1) and a regression-derived equation(2). According to a classification scheme(3), this estimated Koc value suggests that 1,2-diphenylhydrazine has low mobility in soil(SRC).

The Henry's Law constant for 1,2-diphenylhydrazine is estimated as 4.8X10-7 atm-cu m/mole(SRC) derived from its vapor pressure, 4.4X10-4 mm Hg(1), and water solubility, 221 mg/L(2). This Henry's Law constant indicates that 1,2-diphenylhydrazine is expected to be essentially nonvolatile from water surfaces(3). 1,2-Diphenylhydrazine's estimated Henry's Law constant indicates that volatilization from moist soil surfaces is not expected(SRC). 1,2-Diphenylhydrazine is not expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(1).

DRINKING WATER: Detected, not quantified in finished drinking water(1). 1,2-Diphenylhydrazine has been found in drinking water at levels of 1 ug/l(2).

GROUNDWATER: 1,2-Diphenylhydrazine was detected in groundwater samples at Love Canal, Niagara Falls, NY(1). One of 29 groundwater well samples at the Forest Waste Disposal Site, Otisville, MI contained 1,2-diphenylhydrazine at unreported concentrations(2).

1,2-Diphenylhydrazine was detected in 1.2% of 1,205 effluent samples collected in a national survey at a median concn less than 10 ug/l(1). Influent at the Moccasin Bend Wastewater Treatment Plant, Chattanooga, TN contained 1,2-diphenylhydrazine in 14% of 35 samples; 8% of the primary effluent samples contained 1,2-diphenylhydrazine at an average concentration of <1 ug/l (2). In a second study at the same treatment plant, 17% of 29 influent samples, 10% of 30 primary effluent samples, and 0 of 30 secondary effluent samples contained 1,2- diphenylhydrazine, where present, at an average concentration of <1 ug/l(2). Effluent samples collected from the Cedar Creek Wastewater Reclamation Plant, Nassau County, NY contained below detection limit concentrations of 1,2-diphenylhydrazine (detection limit= 0.05 ug/l); influent samples contained 1,2-diphenylhydrazine at 0.1 to 2.5 ug/l(3)

1,2-Diphenylhydrazine was detected in sediment and soil samples at Love Canal, Niagara Fall, NY(1).

1,2-Diphenylhydrazine was detected in the tissues of fish collected nearshore from several Lake Michigan tributaries and embayments(1), and Great Lakes harbors and tributary mouths(2).

The primary route of exposure is through ingestion ... of the chemical.

NIOSH (NOES Survey 1981-1983) has statistically estimated that 977 workers (154 of these are female) are potentially exposed to 1,2-diphenylhydrazine in the US(1). Occupational exposure may be through inhalation and dermal contact with this compound at workplaces where 1,2-diphenylhydrazine is produced or used. Phenylbutazone, a drug used for the treatment of inflammatory conditions (arthritis) and sulfinpyrazone a drug used to treat gouty arthritis have been shown to hydrolyze to 1,2-diphenylhydrazine(2). However, this drug is primarily used as a veterinary medication and its current use in humans is unknown(SRC). Although potential exists for exposure to 1,2-diphenylhydrazine via treatment with these drugs, no information regarding body burden was located in the literature.

Examination of 194 employees in a plant manufacturing benzidine showed 20 cases of tumors in the urinary system after an exposure to 0.03-0.1 ug benzidine and 0.006-3000 ug hydrazobenzene/l of air for 8 years on the average. The highest rate of tumor incidence was between the 6th and 10th year of exposure.

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number U109, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.

1,2-Diphenylhydrazine is a potential candidate for rotary kiln incineration with a temperature range of 820 to 1600 °C and residence times of seconds for liquids and gases; hours for solids. Also a potential candidate for fluidized bed incineration with a temperature range of 450 to 980 °C and residence times of seconds for liquids and gases; longer for solids.

Physical chemical treatment (coagulation/flocculation followed by sedimentation), with hauling of the sludge. ... /Another method is/ wet air oxidation, using a starting concentration of 5 g/l hydrazobenzene, 99.98% of the 1,2-diphenylhydrazine was destroyed in 1 hr at 275 °C and at 320 °C.

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. /Chemical Carcinogens/

For more Disposal Methods (Complete) data for 1,2-DIPHENYLHYDRAZINE (10 total), please visit the HSDB record page.

/GUIDE 153: SUBSTANCES - TOXIC AND/OR CORROSIVE (COMBUSTIBLE)/ Health: TOXIC; inhalation, ingestion, or skin contact with material may cause severe injury or death. Contact with molten substance may cause severe burns to skin and eyes. Avoid any skin contact. Effects of contact or inhalation may be delayed. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may be corrosive and/or toxic and cause pollution. /Phenylhydrazine/

/GUIDE 153: SUBSTANCES - TOXIC AND/OR CORROSIVE (COMBUSTIBLE)/ Fire or Explosion: Combustible material: may burn but does not ignite readily. When heated, vapors may form explosive mixtures with air: indoors, outdoors, and sewers explosion hazards. Those substances designated with a "P" may polymerize explosively when heated or involved in a fire. Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated. Runoff may pollute waterways. Substance may be transported in a molten form. /Phenylhydrazine/

/GUIDE 153: SUBSTANCES - TOXIC AND/OR CORROSIVE (COMBUSTIBLE)/ Public Safety: CALL Emergency Response Telephone Number ... . 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. Keep unauthorized personnel away. Stay upwind. Keep out of low areas. Ventilate enclosed areas. /Phenylhydrazine/

/GUIDE 153: SUBSTANCES - TOXIC AND/OR CORROSIVE (COMBUSTIBLE)/ Protective Clothing: Wear positive pressure self-contained breathing apparatus (SCBA). Wear chemical protective clothing that is specifically recommended by the manufacturer. It may provide little or no thermal protection. Structural firefighters' protective clothing provides limited protection in fire situations ONLY; it is not effective in spill situations where direct contact with the substance is possible. /Phenylhydrazine/

For more DOT Emergency Guidelines (Complete) data for 1,2-DIPHENYLHYDRAZINE (8 total), please visit the HSDB record page.

PRECAUTIONS FOR "CARCINOGENS": Procurement ... of unduly large amt ... should be avoided. To avoid spilling, carcinogens should be transported in securely sealed glass bottles or ampoules, which should themselves be placed inside strong screw-cap or snap-top container that will not open when dropped & will resist attack from the carcinogen. Both bottle & the outside container should be appropriately labelled. ... National post offices, railway companies, road haulage companies & airlines have regulations governing transport of hazardous materials. These authorities should be consulted before ... material is shipped. /Chemical Carcinogens/

PRECAUTIONS FOR "CARCINOGENS": When no regulations exist, the following procedure must be adopted. The carcinogen should be enclosed in a securely sealed, watertight container (primary container), which should be enclosed in a second, unbreakable, leakproof container that will withstand chem attack from the carcinogen (secondary container). The space between primary & secondary container should be filled with absorbent material, which would withstand chem attack from the carcinogen & is sufficient to absorb the entire contents of the primary container in the event of breakage or leakage. Each secondary container should then be enclosed in a strong outer box. The space between the secondary container & the outer box should be filled with an appropriate quantity of shock-absorbent material. Sender should use fastest & most secure form of transport & notify recipient of its departure. If parcel is not received when expected, carrier should be informed so that immediate effort can be made to find it. Traffic schedules should be consulted to avoid ... arrival on weekend or holiday ... /Chemical Carcinogens/

Do not transport with food and feedstuffs.

Symbol: T, N; R: 45-22-50/53; S: 53-45-60-61; Note: E