benzene

H225: Highly Flammable liquid and vapor [Danger Flammable liquids]

H304: May be fatal if swallowed and enters airways [Danger Aspiration hazard]

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

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

H340: May cause genetic defects [Danger Germ cell mutagenicity]

H350: May cause cancer [Danger Carcinogenicity]

H372 **: Causes damage to organs through prolonged or repeated exposure [Danger Specific target organ toxicity, repeated exposure]

P203, P210, P233, P240, P241, P242, P243, P260, P264, P264+P265, P270, P280, P301+P316, P302+P352, P303+P361+P353, P305+P351+P338, P318, P319, P321, P331, P332+P317, P337+P317, P362+P364, P370+P378, P403+P235, P405, and P501 (click each P-code to see the statement)

This chemical does not meet GHS hazard criteria for 0.1% (2 of 1934) of reports.

H225 (99.7%): Highly Flammable liquid and vapor [Danger Flammable liquids]

H304 (99.3%): May be fatal if swallowed and enters airways [Danger Aspiration hazard]

H315 (99.8%): Causes skin irritation [Warning Skin corrosion/irritation]

H319 (99.8%): Causes serious eye irritation [Warning Serious eye damage/eye irritation]

H340 (99.8%): May cause genetic defects [Danger Germ cell mutagenicity]

H350 (99.8%): May cause cancer [Danger Carcinogenicity]

H372 (99.3%): Causes damage to organs through prolonged or repeated exposure [Danger Specific target organ toxicity, repeated exposure]

H412 (17.2%): Harmful to aquatic life with long lasting effects [Hazardous to the aquatic environment, long-term hazard]

P203, P210, P233, P240, P241, P242, P243, P260, P264, P264+P265, P270, P273, P280, P301+P316, P302+P352, P303+P361+P353, P305+P351+P338, P318, P319, P321, P331, P332+P317, P337+P317, P362+P364, P370+P378, P403+P235, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 1934 reports by companies from 47 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Reported as not meeting GHS hazard criteria per 2 of 1934 reports by companies.

There are 46 notifications provided by 1932 of 1934 reports by companies with hazard statement code(s).

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.

H332: Harmful if inhaled [Warning Acute toxicity, inhalation]

H335: May cause respiratory irritation [Warning Specific target organ toxicity, single exposure; Respiratory tract irritation]

H336: May cause drowsiness or dizziness [Warning Specific target organ toxicity, single exposure; Narcotic effects]

H361: Suspected of damaging fertility or the unborn child [Warning Reproductive toxicity]

H370: Causes damage to organs [Danger Specific target organ toxicity, single exposure]

H372: Causes damage to organs through prolonged or repeated exposure [Danger Specific target organ toxicity, repeated exposure]

H401: Toxic to aquatic life [Hazardous to the aquatic environment, acute hazard]

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

P203, P210, P233, P240, P241, P242, P243, P260, P261, P264, P264+P265, P270, P271, P273, P280, P301+P316, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P308+P316, P317, P318, P319, P321, P331, P332+P317, P337+P317, P362+P364, P370+P378, P391, P403+P233, P403+P235, P405, and P501 (click each P-code to see the statement)

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

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

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

P203, P210, P233, P240, P241, P242, P243, P260, P261, P264, P264+P265, P270, P271, P280, P301+P316, P301+P317, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P308+P316, P318, P319, P321, P330, P331, P332+P317, P337+P317, P362+P364, P370+P378, P403+P233, P403+P235, P405, and P501 (click each P-code to see the statement)

P203, P210, P233, P240, P241, P242, P243, P264, P264+P265, P273, P280, P301+P316, P302+P352, P303+P361+P353, P305+P351+P338, P318, P321, P331, P332+P317, P337+P317, P362+P364, P370+P378, P403+P235, P405, and P501 (click each P-code to see the statement)

Fresh air, rest. Refer for medical attention.

Remove contaminated clothes. Rinse skin with plenty of water or shower. 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. Do NOT induce vomiting. 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. 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. Volatile chemicals have a high risk of being aspirated into the victim's lungs during vomiting which increases the medical problems. 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. IMMEDIATELY transport the victim to a hospital. 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)

General First Aid:

· Call 911 or emergency medical service.

· Ensure that medical personnel are aware of the material(s) involved, take precautions to protect themselves and avoid contamination.

· Move victim to fresh air if it can be done safely.

· Administer oxygen if breathing is difficult.

· If victim is not breathing:

-- DO NOT perform mouth-to-mouth resuscitation; the victim may have ingested or inhaled the substance.

-- If equipped and pulse detected, wash face and mouth, then give artificial respiration using a proper respiratory medical device (bag-valve mask, pocket mask equipped with a one-way valve or other device).

-- If no pulse detected or no respiratory medical device available, provide continuous compressions. Conduct a pulse check every two minutes or monitor for any signs of spontaneous respirations.

· Remove and isolate contaminated clothing and shoes.

· For minor skin contact, avoid spreading material on unaffected skin.

· In case of contact with substance, remove immediately by flushing skin or eyes with running water for at least 20 minutes.

· For severe burns, immediate medical attention is required.

· Effects of exposure (inhalation, ingestion, or skin contact) to substance may be delayed.

· Keep victim calm and warm.

· Keep victim under observation.

· For further assistance, contact your local Poison Control Center.

· Note: Basic Life Support (BLS) and Advanced Life Support (ALS) should be done by trained professionals.

Specific First Aid:

· Wash skin with soap and water.

· In case of burns, immediately cool affected skin for as long as possible with cold water. Do not remove clothing if adhering to skin.

(General first aid procedures)

Eye: Irrigate immediately - If this chemical contacts the eyes, immediately wash (irrigate) the eyes with large amounts of water, occasionally lifting the lower and upper lids. Get medical attention immediately.

Skin: Soap wash immediately - If this chemical contacts the skin, immediately wash the contaminated skin with soap and water. If this chemical penetrates the clothing, immediately remove the clothing, wash the skin with soap and water, and get medical attention promptly.

Breathing: Respiratory support

Swallow: Medical attention immediately - If this chemical has been swallowed, get medical attention immediately.

Excerpt from ERG Guide 130 [Flammable Liquids (Water-Immiscible / Noxious)]:

CAUTION: The majority of these products have a very low flash point. Use of water spray when fighting fire may be inefficient.

SMALL FIRE: Dry chemical, CO2, water spray or regular foam. If regular foam is ineffective or unavailable, use alcohol-resistant foam.

LARGE FIRE: Water spray, fog or regular foam. If regular foam is ineffective or unavailable, use alcohol-resistant foam. Avoid aiming straight or solid streams directly onto the product. If it can be done safely, move undamaged containers away from the area around the fire.

FIRE INVOLVING TANKS, RAIL TANK CARS OR HIGHWAY TANKS: Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles. Cool containers with flooding quantities of water until well after fire is out. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks in direct contact with flames. For massive fire, use unmanned master stream devices or monitor nozzles; if this is impossible, withdraw from area and let fire burn. (ERG, 2024)

Use foam, water spray, carbon dioxide, powder. In case of fire: keep drums, etc., cool by spraying with water.

- Benzene is highly flammable.

- The agent will be easily ignited by heat, sparks, or flames.

- Fire will produce irritating, corrosive, and/or toxic gases.

- Benzene reacts violently with oxidants and halogens, causing a fire hazard.

- Vapors may travel to the source of ignition and flash back.

- Run-off to sewers may create a fire hazard.

- Caution: The agent has a very low flash point. Use of water spray when fighting fires may be inefficient.

- For small fires, use dry chemical, carbon dioxide, water spray, or regular foam.

- For large fires, use water spray, fog, or regular foam. Do not use straight streams. Move containers from the fire area if it is possible to do so without risk to personnel.

- For fire involving tanks or car/trailer loads, fight the fire from maximum distance or use unmanned hose holders or monitor nozzles. Cool containers with flooding quantities of water until well after the fire is out. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tanks. Always stay away from tanks engulfed in fire.

- For massive fire, use unmanned hose holders or monitor nozzles; if this is impossible, withdraw from the area and let the fire burn.

- Run-off from fire control or dilution water may cause pollution.

- If the situation allows, control and properly dispose of run-off (effluent).

Approach fire from upwind to avoid hazardous vapors. Use water spray, dry chemical, foam, or carbon dioxide. Use water spray to keep fire-exposed containers cool.

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 spread fire. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. Use foam, dry chemical, or carbon dioxide.

Suitable extinguishing media: Use water spray, alcohol-resistant foam, dry chemical or carbon dioxide.

Advice for firefighters: Wear self contained breathing apparatus for fire fighting if necessary.

Use water spray to cool unopened containers.

Vapors are heavier than air and may travel to a source of ignition & flash back. Liquid floats on water and may travel to a source of ignition and spread fire.

Special hazards arising from the substance or mixture: Carbon oxides Flash back possible over considerable distance. Container explosion may occur under fire conditions.

· 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.

· Keep unauthorized personnel away.

· Stay upwind, uphill and/or upstream.

· Ventilate closed spaces before entering, but only if properly trained and equipped.

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

· All equipment used when handling the product must be grounded.

· Do not touch or walk through spilled material.

· Stop leak if you can do it without risk.

· Prevent entry into waterways, sewers, basements or confined areas.

· A vapor-suppressing foam may be used to reduce vapors.

· Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers.

· Use clean, non-sparking tools to collect absorbed material.

Large Spill

· Dike far ahead of liquid spill for later disposal.

· Water spray may reduce vapor, but may not prevent ignition in closed spaces.

Excerpt from ERG Guide 130 [Flammable Liquids (Water-Immiscible / Noxious)]:

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

LARGE SPILL: Consider initial downwind evacuation for at least 300 meters (1000 feet).

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)

Immediate precautionary measure

· Isolate spill or leak area for at least 50 meters (150 feet) in all directions.

· Consider initial downwind evacuation for at least 300 meters (1000 feet).

· 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.

Remove all ignition sources. Evacuate danger area! Consult an expert! Personal protection: complete protective clothing including self-contained breathing apparatus. Do NOT wash away into sewer. Do NOT let this chemical enter the environment. Collect leaking and spilled liquid in sealable containers as far as possible. Absorb remaining liquid in sand or inert absorbent. Then store and dispose of according to local regulations.

For spills on water, contain with booms or barriers, use surface acting agents to thicken spilled materials. Remove trapped materials with suction hoses.

Small spills of benzene can be taken up by sorption on carbon or synthetic sorbent resins. Flush area with water. For large quantities, if response is rapid, benzene can be skimmed off the surface. Straw may be used to mop slicks.

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/

Eliminate all ignition sources. Stop or control the leak, if this can be done without undue risk. Use water spray to cool and disperse vapors, protect personnel, and dilute spills to form nonflammable mixtures. Absorb in noncombustible material for proper disposal. Control runoff and isolate discharged material for proper disposal.

For more Cleanup Methods (Complete) data for BENZENE (9 total), please visit the HSDB record page.

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number F005, U019, D018, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.

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.

Biodegradation, incineration: Benzene is biodegradable. Diluted aqueous soln, therefore, are drained into sewage treatment plants and decomposed there by anaerobic bacteria. Solvent mixtures and sludges of higher concn are burnt in special waste incinerators if a recovery process is uneconomical.

This flammable liquid burns with a very smoky flame. Dilution with alcohol or acetone is suggested to minimize smoke. Recommendable methods: Use as boiler fuel, incineration. Not recommendable: Landfill, discharge to sewer.

For more Disposal Methods (Complete) data for BENZENE (31 total), please visit the HSDB record page.

SRP: The scientific literature for the use of contact lenses by industrial workers is inconsistent. The benefits or detrimental effects of wearing contact lenses depend not only upon the substance, but also on factors including the form of the substance, characteristics and duration of the exposure, the uses of other eye protection equipment, and the hygiene of the lenses. However, there may be individual substances whose irritating or corrosive properties are such that the wearing of contact lenses would be harmful to the eye. In those specific cases, contact lenses should not be worn. In any event, the usual eye protection equipment should be worn even when contact lenses are in place.

SRP: Local exhaust ventilation should be applied wherever there is an incidence of point source emmissions or dispersion of regulated contaminants in the work area. Ventilation control of the contaminant as close to its point of generation is both the most economical and safest method to minimize personnel exposure to airborne contaminants.

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/

For more Preventive Measures (Complete) data for BENZENE (19 total), please visit the HSDB record page.

Excerpt from ERG Guide 130 [Flammable Liquids (Water-Immiscible / Noxious)]:

ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area. All equipment used when handling the product must be grounded. Do not touch or walk through spilled material. Stop leak if you can do it without risk. Prevent entry into waterways, sewers, basements or confined areas. A vapor-suppressing foam may be used to reduce vapors. Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers. Use clean, non-sparking tools to collect absorbed material.

LARGE SPILL: Dike far ahead of liquid spill for later disposal. Water spray may reduce vapor, but may not prevent ignition in closed spaces. (ERG, 2024)

Fireproof. Separated from food and feedstuffs, oxidants and halogens. Store in an area without drain or sewer access.

Keep in well closed containers in a cool place and away from fire.

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/

Conditions for safe storage, including any incompatibilities: Keep container tightly closed in a dry and well-ventilated place. Containers which are opened must be carefully resealed and kept upright to prevent leakage.

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

· Structural firefighters' protective clothing provides thermal protection but only limited chemical protection.

Biological Exposure Indices (BEI) [ACGIH] - S-phenylmercapturic acid in urine = 25 ug/g creatinine; t,t-Muconic acid in urine = 500 ug/g creatinine; sample at end of shift;

AEGL 1: Notable discomfort, irritation, or certain asymptomatic non-sensory effects. However, the effects are not disabling and are transient and reversible upon cessation of exposure (Unit: ppm)

AEGL 2: Irreversible or other serious, long-lasting adverse health effects or an impaired ability to escape (Unit: ppm)

AEGL 3: Life-threatening health effects or death (Unit: ppm)

Lower Explosive Limit (LEL) = 14,000 ppm * = >10% LEL; ** = >50% LEL AEGL 3 - 10 mins = ** 9,700 ppm For values denoted as * safety considerations against the hazard(s) of explosion(s) must be taken into account. For values denoted as ** extreme safety considerations against the hazard(s) of explosion(s) must be taken into account.

AEGLs Status: Interim

52 [ppm]

800 [ppm]

4000 [ppm]

Ca TWA 0.1 ppm ST 1 ppm See Appendix A

1.0 [ppm], STEL(OSHA) = 5 ppm (see CFR 1910.1028)

[1910.1028] TWA 1 ppm ST 5 ppm See Appendix F

500 ppm ; A potential occupational carcinogen. (NIOSH, 2024)

500.0 [ppm]

Excerpts from Documentation for IDLHs: Other human data: It has been stated that 3,000 ppm is endurable for 0.5 to 1 hour [Flury 1928]. It has also been stated that exposure at 19,000 to 20,000 ppm for 5 to 10 minutes is fatal; exposure at 7,500 ppm for 30 minutes is dangerous; exposure at 1,500 ppm for 60 minutes induces serious symptoms; exposure at 500 ppm for 60 minutes leads to symptoms of illness; exposure at 50 to 150 ppm for 5 hours produces headache, lassitude, and weakness; and exposure at 25 ppm for 8 hours has no effect [Gerarde 1960].

NIOSH usually recommends that occupational exposures to carcinogens be limited to the lowest feasible concentration.

Ca [500 ppm]

See: 71432

0.2 [ppm]

8 hr Time Weighted Avg (TWA): 0.5 ppm, skin; 15 min Short Term Exposure Limit (STEL): 2.5 ppm, skin.

A1; Confirmed human carcinogen.

Biological Exposure Index (BEI): Determinant: t,t-muconic acid in urine; Sampling Time: end of shift; BEI: 500 ug/g creatinine; Notation: The determinant may be present in biological specimens collected from subjects who have not been occupationally exposed, at a concentration which could affect interpretation of the result. Such background concentrations are incorporated in the BEI value.

Biological Exposure Index (BEI): Determinant: S-phenylmercapturic acid in urine; Sampling Time: end of shift; BEI: 25 ug/g creatinine. The determinant may be present in biological specimens collected from subjects who have not been occupationally exposed, at a concentration which could affect interpretation of the result. Such background concentrations are incorporated in the BEI value.

0.5 ppm as TWA; 2.5 ppm as STEL; (skin); A1 (confirmed human carcinogen); BEI issued.

3.25 mg/m

carcinogen category: 1; germ cell mutagen group: 3A; skin absorption (H)

Acute Inhalation: 0.009 ppm (L134)

Intermediate Inhalation: 0.006 ppm (L134)

Chronic Inhalation: 0.003 ppm (L134)

Chronic Oral: 0.0005 mg/kg/day (L134)

CAUTION: The majority of these products have a very low flash point. Use of water spray when fighting fire may be inefficient.

Small Fire

· Dry chemical, CO2, water spray or regular foam. If regular foam is ineffective or unavailable, use alcohol-resistant foam.

Large Fire

· Water spray, fog or regular foam. If regular foam is ineffective or unavailable, use alcohol-resistant foam.

· Avoid aiming straight or solid streams directly onto the product.

· If it can be done safely, move undamaged containers away from the area around the fire.

Fire Involving Tanks, Rail Tank Cars or Highway Tanks

· Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles.

· Cool containers with flooding quantities of water until well after fire is out.

· Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank.

Benzene appears as a clear colorless liquid with a petroleum-like odor. Flash point less than 0 °F. Less dense than water and slightly soluble in water. Hence floats on water. Vapors are heavier than air.

CBI; Gas Vapor; Liquid; Gas Vapor; Liquid

Colorless to light-yellow liquid with an aromatic odor. Note: A solid below 42 degrees F; [NIOSH]

COLOURLESS LIQUID WITH CHARACTERISTIC ODOUR.

Highly flammable colorless to light-yellow liquid with a petroleum-like odor.

Colorless to light-yellow liquid with an aromatic odor. [Note: A solid below 42 °F.]

Clear, colorless to light yellow liquid at room temperature. Benzene is a solid below 42°F (5.6°C).

Clear, colorless liquid

Orthorhombic prisms or liquid

Colorless to light-yellow liquid [Note: A solid below 42 degrees F]

Aromatic odor

Gasoline-like odor; rather pleasant aromatic odor. Odor threshold = 4.68 ppm.

Taste threshold in water is 0.5-4.5 mg/l.

176.2 °F at 760 mmHg (NTP, 1992)

80.08 °C

80.00 to 81.00 °C. @ 760.00 mm Hg

176.2 °F

80.09 °C @760 [mm Hg]

41.9 °F (NTP, 1992)

5.558 °C

12 °F (NTP, 1992)

12 °F (-11 °C) Closed Cup

-11.0 °C (12.2 °F) (Closed cup)

-11 °C c.c.

1 to 5 mg/mL at 64 °F (NTP, 1992)

In water, 1.79X10+3 mg/L at 25 °C

Miscible with alcohol, chloroform, ether, carbon disulfide, acetone, oils, carbon tetrachloride, and glacial acetic acid

Miscible with ethanol, ethyl ether, acetone, chloroform; coluble in carbon tetrachloride

1.79 mg/mL

Solubility in water, g/100ml at 25 °C: 0.18

0.879 at 68 °F (USCG, 1999) - Less dense than water; will float

0.8756 g/cu cm at 20 °C

SPECIFIC DISPERSION 189.6; DENSITY OF SATURATED VAPOR-AIR MIXT AT 760 MM HG (AIR= 1) IS 1.22 AT 26 °C; PERCENT IN SATURATED IN AIR AT 760 MM HG IS 13.15 AT 26 °C

Relative density (water = 1): 0.88

0.8765 @ 20°C

2.77 (NTP, 1992) - Heavier than air; will sink (Relative to Air)

2.8 (Air = 1)

Relative vapor density (air = 1): 2.7

60 mmHg at 59 °F ; 76 mmHg at 68 °F (NTP, 1992)

94.8 [mmHg]

Highly flammable. Slightly soluble in water.

Hydrocarbons, Aromatic

Highly Flammable

BENZENE reacts vigorously with allyl chloride or other alkyl halides even at -70 °C in the presence of ethyl aluminum dichloride or ethyl aluminum sesquichloride. Explosions have been reported [NFPA 491M 1991]. Ignites in contact with powdered chromic anhydride [Mellor 11:235 1946-47]. Incompatible with oxidizing agents such as nitric acid. Mixtures with bromine trifluoride, bromine pentafluoride, iodine pentafluoride, iodine heptafluoride and other interhalogens can ignite upon heating [Bretherick 5th ed. 1995]. Benzene and cyanogen halides yield HCl as a byproduct (Hagedorn, F. H. Gelbke, and Federal Republic of Germany. 2002. Nitriles. In Ullmann's Encyclopedia of Industrial Chemistry. Wiley-VCH Verlag GmbH & Co. KGaA.). The reaction of benzene and trichloroacetonitrile evolves toxic chloroform and HCl gases. (Hagedorn, F., H.-P. Gelbke, and Federal Republic of Germany. 2002. Nitriles. In Ullmann's Encyclopedia of Industrial Chemistry. Wiley-VCH Verlag GmbH & Co. KGaA.).

Reacts violently with iodine pentafluoride.

Hydrogenation of benzene to cyclohexane was effected in a fixed bed reactor at 210-230 °C, but a fall in conversion was apparent. Increasing the bed temp by 10 °C & the hydrogen flow led to a large increase in reaction rate which the interbed cooling coils could not handle, & an exotherm to 280 °C developed, with a hot spot around 600 °C which bulged the reactor wall.

Benzene ... ignites in contact with /iodine heptafluoride/ gas ...

Dioxygenyl tetrafluoroborate is a very powerful oxidant, addition of a small particle to small samples of benzene ... at ambient temp ... /caused/ ignition.

For more Hazardous Reactivities and Incompatibilities (Complete) data for BENZENE (25 total), please visit the HSDB record page.

Strong oxidizers, many fluorides & perchlorates, nitric acid

CDC-ATSDR Toxicological Profile

IDENTIFICATION AND USE: Benzene is a clear, colorless liquid with a sweet aromatic odor. It is used mainly as a starting material in manufacturing other chemicals, including detergents, pesticides, plastics and resins, synthetic rubber, aviation fuel, pharmaceuticals, dye, explosives, PCB gasoline, flavors and perfumes, paints and coatings, nylon intermediates, photographic chemicals. HUMAN EXPOSURE AND TOXICITY: Immediate signs and symptoms of exposure to benzene: People who breathe in high levels of benzene may develop drowsiness, dizziness, rapid or irregular heartbeat, headaches, tremors, confusion unconsciousness, death. Eating foods or drinking beverages containing high levels of benzene can cause vomiting, irritation of the stomach, dizziness, sleepiness, convulsions, rapid or irregular heartbeat, death. Long-term (a year or more) exposure to benzene causes harmful effects on the bone marrow, resulting in anemia and excessive bleeding. It can also affect the immune system, increasing the chance for infection. Some women who breathed high levels of benzene for many months had irregular menstrual periods and a decrease in the size of their ovaries. Acute deaths from benzene exposure at high concentrations have been due to ventricular fibrillation caused by exertion and release of epinephrine. Benzene causes cancer in humans. A retrospective cohort study was conducted in 233 benzene factories and 83 control factories in 12 cities in China. The benzene cohort and the control cohort consisted of 28,460 benzene exposed workers and 28,257 control workers. The leukemia mortality rate was 14/100,000 person-years in the benzene cohort and 2/100,000 person-years in the control cohort. Most (76.6%) cases of benzene leukemia were of the acute type. The mortality due to benzene leukemia was high in organic synthesis plants followed by painting and rubber synthesis industries. The concentration of benzene to which patients with a leukemia were exposed ranged from 10 to 1000 mg/cu m (mostly from 50 to 500 mg/cu m). Benzene is genotoxic in humans: a significantly increased frequency of chromatid and isochromatid breaks in the cultured lymphocytes of exposed workers has been reported, as well as a significant increase of peripheral blood lymphocyte chromosomal aberrations. Metabolic activation of benzene by rat liver microsomes induced sister chromatid exchanges and cell division delays in cultured human lymphocytes. Occupational exposure to benzene may occur through inhalation and dermal contact. The general population may be exposed to benzene via inhalation of ambient air, ingestion of food and drinking water, and dermal contact with consumer products containing benzene. ANIMAL TOXICITY STUDIES: Experimental animal studies, both inhalation and oral, also support the evidence that exposure to benzene increases the risk of cancer in multiple organ systems, including the hematopoietic system, oral and nasal cavities, liver, forestomach, preputial gland, lung, ovary, and mammary gland. Rats exposed to 3,526-8,224 ppm of benzene in a closed chamber for 15 minutes exhibited an increased number of ectopic ventricular beats. In developmental study, rats exposed to 10, 50, or 500 ppm (32, 160 & 1600 mg/cu m) of benzene for 7 hr/day had low incidence of brain and skeletal defects. Rats exposed continuously to 209.7 ppm for 10 days prior to breeding showed a complete absence of pregnancy. 1/10 rats exposed to 19.8 ppm had resorbed embryos. Genotoxicity studies have demonstrated the induction of chromosomal aberrations in bone-marrow cells from mice, rats, and rabbits treated with single or multiple daily doses of benzene ranging from about 0.2 to 2.0 mL/kg per day given either sc or ip. The major metabolites of benzene are phenol, hydroquinone, and catechol. The route of exposure has little effect on the subsequent metabolism of benzene to hemotoxic metabolites. ECOTOXICITY STUDIES: Young Coho salmon mortality was 12/20 at 50 ppm after 24 hr up to 96 hr and 30/30 at 100 ppm after 24 hr in artificial seawater at 8 °C. Herring and anchovy larvae studies showed that 35-45 ppm caused delay in development of eggs and produced abnormal larvae; 10-35 ppm caused delay in development of larvae, decrease in feeding and growth, and increase in respiration. Blue crab juveniles when exposed to sublethal concentrations of benzene (0.1 or 5.0 ppm) in a static system showed an increase in the time needed to complete a molt cycle (50 days in case of benzene-exposed crab, as compared to 33 days for controls), a slower rate of growth of regenerating limb buds, and a depressed activity of ATPase in mitochrondria. Oxygen consumption by the crab decreased from exposure to 1.0 ppm benzene.

The toxic agents of benzene are its metabolites. Benzene is able increase its toxicity by inducing cytochrome P450 2E1, its main metabolic enzyme. Benzene's primary toxic effects are decreases in haematological cell counts and bone marrow cellularity. The decrease in blood cell count may be due to the binding of metabolites such as benzene oxide to the blood proteins albumin and haemoglobin. In the bone marrow, phenolic metabolites can be metabolized by bone marrow peroxidases to highly reactive semiquinone radicals and quinones that stimulate the production of reactive oxygen species. This and direct metabolite binding leads to damage to tubulin, histone proteins, and topoisomerase II. Some metabolites also exert mutagenic effects by inhibiting other DNA associated proteins, such as mitochondrial DNA polymerase and ribonucleotide reductase, as well as covalently binding to DNA itself, causing effects such as strand breakage, mitotic recombination, chromosome translocations, and aneuploidy. (L5)

Hematologic

4 x 10 ^-3 mg/kg-day

3 x 10 ^-2 mg/m^3

Volatile Organic Compound (VOC)

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

Classification of carcinogenicity: 1) evidence in humans: sufficient; 2) evidence in animals: sufficient; Overall summary evaluation of carcinogenic risk to humans is group 1: The chemical is carcinogenic to humans. /From table/

A1; Confirmed human carcinogen.

Cancer Classification: Carcinogenic to Humans

WEIGHT-OF-EVIDENCE CHARACTERIZATION: Benzene is classified as a "known" human carcinogen (Category A) under the Risk Assessment Guidelines of 1986. Under the proposed revised Carcinogen Risk Asessment Guidelines (USEPA, 1996), benzene is characterized as a known human carcinogen for all routes of exposure based upon convincing human evidence as well as supporting evidence from animal studies. Epidemiologic studies and case studies provide clear evidence of a causal association between exposure to benzene and acute nonlymphocytic leukemia and also suggest evidence for chronic nonlymphocytic leukemia and chronic lymphocytic leukemia. Other neoplastic conditions that are associated with an increased risk in humans are hematologic neoplasms, blood disorders such as preleukemia and aplastic anemia, Hodgkin's lymphoma, and myelodysplastic syndrome. These human data are supported by animal studies. The experimental animal data add to the argument that exposure to benzene increases the risk of cancer in multiple species at multiple organ sites (hematopoietic, oral and nasal, liver, forestomach, preputial gland, lung, ovary, and mammary gland). It is likely that these responses are due to interactions of the metabolites of benzene with DNA ... Recent evidence supports the viewpoint that there are likely multiple mechanistic pathways leading to cancer and, in particular, to leukemogenesis from exposure to benzene. HUMAN CARCINOGENICITY DATA: Benzene is a known human carcinogen based upon evidence presented in numerous occupational epidemiological studies. Significantly increased risks of leukemia, chiefly acute myelogenous leukemia, have been reported in benzene-exposed workers in the chemical industry, shoemaking and oil refineries. ANIMAL CARCINOGENICITY DATA:... many experimental animal studies, both inhalation and oral, also support the evidence that exposure to benzene increases the risk of cancer in multiple organ systems, including the hematopoietic system, oral and nasal cavities, liver, forestomach, preputial gland, lung, ovary, and mammary gland ....

Benzene: known to be a human carcinogen. Carcinogenicity: Benzene is known to be a human carcinogen based on sufficient evidence of carcinogenicity from studies in humans.

Group 1: Carcinogenic to humans

Volume 29: (1982) Some Industrial Chemicals and Dyestuffs

Volume Sup 7: Overall Evaluations of Carcinogenicity: An Updating of IARC Monographs Volumes 1 to 42, 1987; 440 pages; ISBN 92-832-1411-0 (out of print)

Volume 100F: (2012) Chemical Agents and Related Occupations

Volume 120: (2018) Benzene

TR-289: Toxicology and Carcinogenesis Studies of Benzene (CASRN 71-43-2) in F344/N Rats and B6C3F1 Mice (Gavage Studies) (1986 )

07/27/84

Clear Evidence

Under the conditions of these 2-year gavage studies, there was clear evidence of carcinogenicity of benzene for male F344/N rats, for female F344/N rats, for male B6C3F1 mice, and for female B6C3F1 mice. For male rats, benzene caused increased incidences of Zymbal gland carcinomas, squamous cell papillomas and squamous cell carcinomas of the oral cavity, and squamous cell papillomas and squamous cell carcinomas of the skin. For female rats, benzene caused increased incidences of Zymbal gland carcinomas and squamous cell papillomas and squamous cell carcinomas of the oral cavity. For male mice, benzene caused increased incidences of Zymbal gland squamous cell carcinomas, malignant lymphomas, alveolar/bronchiolar carcinomas and alveolar/bronchiolar adenomas or carcinomas (combined), harderian gland adenomas, and squamous cell carcinomas of the preputial gland. For female mice, benzene caused increased incidences of malignant lymphomas, ovarian granulosa cell tumors, ovarian benign mixed tumors, carcinomas and carcinosarcomas of the mammary gland, alveolar/bronchiolar adenomas, alveolar/bronchiolar carcinomas, and Zymbal gland squamous cell carcinomas. Dose-related lymphocytopenia was observed for male and female F344/N rats and male and female B6C3F1 mice.

1, carcinogenic to humans. (L135)

Benzene causes harmful effects on the bone marrow and also decreases blood cell counts, leading to blood disorders such as anemia. It can also cause excessive bleeding and affect the immune system, increasing the chance for infection. Benzene is also a known carcinogen, as chronic exposure to high levels has been shown to cause leukemia, particularly acute myelogenous leukemia. (L5)

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

inhalation, skin absorption, ingestion, skin and/or eye contact

Benzene can be absorbed into the body by inhalation, ingestion, or skin contact. Inhalation is an important route of exposure.

Inhalation (L5)

Dizziness. Drowsiness. Headache. Nausea. Shortness of breath. Convulsions. Unconsciousness.

MAY BE ABSORBED! Dry skin. Redness. Pain. Further see Inhalation.

Redness. Pain.

Abdominal pain. Sore throat. Vomiting. Further see Inhalation.

irritation eyes, skin, nose, respiratory system; dizziness; headache, nausea, staggered gait; anorexia, lassitude (weakness, exhaustion); dermatitis; bone marrow depression; [potential occupational carcinogen]

- High concentrations of vapor: Irritation and blurred vision.

- Liquid: Burning pain and possibly reversible loss (sloughing) and injury to the surface of the cornea.

- Nine to 12 g: Irritation of the stomach causing nausea, vomiting (emesis), and diarrhea; burning sensation to the mouth, esophagus, and stomach; abnormally rapid heart rate (tachycardia); staggering gait, drowsiness (somnolence), loss of consciousness, or altered mental status; and inflammation of the lungs and respiratory failure.

- Slightly higher ingested doses: Dizziness and excitation followed by a flushed appearance, difficulty breathing or shortness of breath (dyspnea), feeling of chest tightness, headache, and generalized weakness.

- At the highest ingested doses: In addition to the above adverse health effects, symptoms include euphoria and excitation followed by fatigue, coma, and death.

- 700 to 3,000 ppm: Drowsiness, dizziness, headaches, tremors, confusion, unconsciousness, abnormally rapid heart rate (tachycardia), and irritation of the moist linings (mucous membranes of the respiratory tract).

- 3,000 ppm and above: Slow and shallow breathing; a deeper level of unconsciousness, due to narcotic-like action on the CNS; and with prolonged exposures, seizures, paralysis, abnormal (potentially fatal) heart rhythms (cardiac arrhythmia), and cessation of breathing (apnea).

LC100; Species: Tetrahymena pyriformis /protozoa/; Concentration: 1000 mg/L for 24 hr /Conditions of bioassay not specified/

LC50; Species: Palaemonetes pugio (grass shrimp); Concentration: 27 ppm for 96 hr /Conditions of bioassay not specified/

LC50; Species: Cancer magister (crab larvae) stage 1; Concentration: 108 ppm for 96 hr /Conditions of bioassay not specified/

LC50; Species: Crangon franciscorum (shrimp); Concentration: 20 ppm for 96 hr /Conditions of bioassay not specified/

For more Ecotoxicity Values (Complete) data for BENZENE (74 total), please visit the HSDB record page.

/AQUATIC SPECIES/ Toxicity threshold (cell multiplication inhibition test): bacteria (Pseudomonas putida) 92 mg/L; algae (Microcystis aeruginosa) >1400 mg/L; green algae (Scenedesmus quadricauda) >1400 mg/L; protozoa (Entosiphon sulcatum) >700 mg/L, & (Uronema parduczi Chatton-Lwoff) 486 mg/L. Algae (Chlorella vulgaris) /showed/ 50% reduction of cell numbers versus controls after 1 day incubation at 20 °C at 525 ppm. Inhibition of photosynthesis (of a freshwater, nonaxenic unialgal culture of Selenastrum capricornutum) at 10 mg/L, 95% carbon-14 fixation (versus controls); at 100 mg/L, 84% carbon-14 fixation (versus controls); at 1000 mg/L, 5% carbon-14 fixation (versus controls).

/AQUATIC SPECIES/ ... Young Coho salmon /showed/ no significant mortalities up to 10 ppm after 96 hr in artificial seawater at 8 °C ... Mortality /was/ 12/20 at 50 ppm after 24 hr up to 96 hr and 30/30 at 100 ppm after 24 hr in artificial seawater at 8 °C. Herring and anchovy larvae (Clupea pallasi and Engraulis mordex) /studies showed that/ 35-45 ppm caused delay in development of eggs and /produced/ abnormal larvae; 10-35 ppm caused delay in development of larvae, decrease in feeding and growth, and increase in respiration.

/AQUATIC SPECIES/ Blue crab juveniles when exposed to sublethal concentration of benzene (0.1 or 5.0 ppm) in a static system showed an increase in the time needed to complete a molt cycle (50 days in case of benzene-exposed crab, as compared to 33 days for controls), a slower rate of growth of regenerating limb buds, and a depressed activity of ATPase in mitochrondria. Oxygen consumption by the crab decreased from exposure to 1.0 ppm benzene.

/PLANTS/ In higher plants, benzene administered in aqueous solution or as vapor is translocated and metabolized. The proposed sequence of benzene metabolism in plants is benzene /to/ phenol /to/ pyrocatechol /to/ o-benzoquinone /to/ muconic acid.

1.20e+00

5.10e+00

3.60e-01

1.60e+00

4.60e-01

5.00e+00

2.30e-04

2.60e-03

5.50e-02

4.00e-03

3.00e-02

Volatile

1.82e+03

1.20e+02

5.10e+02

3.60e+01

1.60e+02

4.60e+01

The substance is toxic to aquatic organisms. The substance may cause long-term effects in the aquatic environment.

Benzene's production, existence in gasoline, and use in the production of ethylbenzene and styrene as well as many other chemicals may result in its release to the environment through various waste streams. Benzene is found in volcanoes, as a constituent of crude oil, from forest fires, and as a plant volatile. If released to air, a vapor pressure of 94.8 mm Hg at 25 °C indicates benzene will exist solely as a vapor in the ambient atmosphere. Vapor-phase benzene will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in air is estimated to be 13 days. Vapor-phase benzene is also degraded by ozone radicals and nitrate found in the atmosphere but at such low rates as to not be important. A half-life of 16.9 days was reported for photolysis of benzene dissolved in deionized water saturated with air exposed to sunlight. Since benzene is very water soluble, it may be removed from the atmosphere by rain. If released to soil, benzene is expected to have high mobility based upon a Koc of 85. Volatilization from moist soil surfaces is expected to be an important fate process based upon a Henry's Law constant of 5.56X10-3 atm-cu m/mole. Benzene may volatilize from dry soil surfaces based upon its vapor pressure. Using a base-rich para-brownish soil incubated for 10 weeks, 20 ppm benzene was 24% degraded in 1 week, 44% in 5 weeks, and 47% in 10 weeks, indicating that biodegradation may be an important environmental fate process in soil. If released into water, benzene is not expected to adsorb to sediment and suspended solids in water based upon the Koc. Volatilization from water surfaces is expected to be an important fate process based upon this compound's Henry's Law constant. Estimated volatilization half-lives for a model river and model lake are 2.7 hrs and 3.5 days, respectively. Utilizing the Japanese MITI test, 40% of the Theoretical BOD was reached in 2 weeks indicating that biodegradation is important environmental fate process in water. In aqueous solution, benzene will react with hydroxyl radical (OH radical average concentration = 1.0X10-17 molec/cu cm) at a reaction rate of 7.8X10+9 L/mol sec which results in an estimated half-life of 103 days. A BCF ranging from 1.1-20 suggests bioconcentration in aquatic organisms is low. Hydrolysis is not expected to occur due to the lack of hydrolyzable functional groups. Occupational exposure to benzene may occur through inhalation and dermal contact with this compound at workplaces where benzene is produced or used. Monitoring data indicate that the general population may be exposed to benzene via inhalation of ambient air, ingestion of food and drinking water, and dermal and inhalation contact with consumer products containing this compound. Benzene is a component of cigarette smoke and is widely detected in atmospheric samples due to its presence in gasoline. (SRC)

... Benzene has been reported to be a natural constituent of fruits, vegetables, meats, and dairy products with concentrations ranging from 2 ug/kg in canned beef to 2100 ug/kg for eggs.

Benzene is found naturally in the environment from volcanoes, as a natural constituent of crude oil, from forest fires and as a plant volatile(1,2). Benzene concentrations range from 100-200 parts per trillion over the Pacific and Atlantic Oceans due to seepage and spillage of oil into the oceans(3).

Benzene's production and use in the manufacture of industrial chemicals such as polymers, detergents, pesticides, pharmaceuticals, dyes, plastics, resins, as an organic solvent for waxes, resins, oils, natural rubber, etc, a reference for quantitating compounds, and as a gasoline additive(1) may result in its release to the environment through various waste streams(SRC).

Benzene enters the environment from production, storage, transport, venting, and combustion of gasoline; and from production, storage, and transport of benzene itself. Other sources result from its use as an intermediate in the production of other chemicals, and as a solvent, from spills, including oil spills; from its indirect production in coke ovens; from nonferrous metal manufacture, ore mining, wood processing, coal mining and textile manufacture, and from cigarette smoke(1,2).

Benzene is the largest volume aromatic petrochemical; ethylbenzene is the largest chemical outlet for benzene, and nearly all is consumed for the production of styrene(1). Benzene has been detected in cigarette smoke ranging from 47-64 ppm(2). The world wide release of benzene into the environment is estimated to be 4-5 Tg/yr with 0.6 Tg/yr coming from the United States alone(3). Leachate from landfills is also a source of benzene in the environment(4).

TERRESTRIAL FATE: Based on a classification scheme(1), a Koc value of 85(2), indicates that benzene is expected to have high mobility in soil(SRC). Volatilization of benzene from moist soil surfaces is expected to be an important fate process(SRC) given a Henry's Law constant of 5.56X10-3 atm-cu m/mole(3). The potential for volatilization of benzene from dry soil surfaces may exist(SRC) based upon a vapor pressure of 94.8 mm Hg(4). Using a base-rich para-brownish soil incubated for 10 weeks, 20 ppm benzene was 24% degraded in 1 week, 44% in 5 weeks, and 47% in 10 weeks(5), indicating that biodegradation may be an important environmental fate process in soil(SRC). Anaerobic degradation of benzene in soil is not expected to be an important loss process based on various studies(6,7). In one study of chemical biotransformation under nitrate- and sulfate-reducing conditions, benzene was found to be stable for 60 days(6). In a related study, benzene did not undergo biodegradation in situ nor in laboratory controlled soil samples under denitrifying conditions(7).

AQUATIC FATE: Based on a classification scheme(1), a Koc value of 85(2), indicates that benzene is not expected to adsorb to sediment and suspended solids in water(SRC). Volatilization from water surfaces is expected(3) based upon a Henry's Law constant of 5.56X10-3 atm-cu m/mole(4). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 1 hr and 3.5 days, respectively(SRC). In aqueous solution, benzene will react with hydroxyl radical at a reaction rate of 7.8X10+9 L/mol sec; using the average OH radical concentration (1.0X10-17 molec/cu cm), benzene would have a half-life of 103 days(5). According to a classification scheme(6), BCFs ranging from 1.1-20(7) suggests the potential for bioconcentration in aquatic organisms is low. Utilizing the Japanese MITI test, 40% of the Theoretical BOD was reached in 2 weeks(8) indicating that biodegradation is important environmental fate process in water(SRC). Anaerobic degradation of benzene in water is not expected to be an important loss process based on various studies(9). In one study of chemical biotransformation under nitrate- and sulfate-reducing conditions, benzene was found to be stable for 60 days(5).

AQUATIC FATE: Evaporation was the primary loss mechanism in winter in a mesocosm experiment which simulated a northern bay where the half-life was 13 days(1). In spring and summer the half-lives were 23 and 3.1 days, respectively(1). In these cases biodegradation plays a major role and takes about 2 days(1). However, acclimation is critical and this takes much longer in the colder water in spring(1). According to one experiment, benzene has a half-life of 17 days due to photochemical degradation(2) which could contribute to benzene's removal. In situations of cold water, poor nutrients, or other conditions less conducive to microbial growth, photolysis will play a important role in degradation(SRC). The half-life of benzene in sea water is about 5 hrs(3) based on its Henry's Law constant of 5.56X10-3 atm-cu m/mole(4). The average first-order rate constant for elimination of benzene in the epilimnion region of Lake Zurich, Switzerland during summer (boating season) is 0.080/day(5).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), benzene, which has a vapor pressure of 94.8 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase benzene is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC); the half-life for this reaction in air is estimated to be 13 days(SRC), calculated from its rate constant of 1.23X10-12 cu cm/molecule-sec at 25 °C(3). The half-life in polluted atmospheres which contain nitrogen oxides or sulfur dioxide has been observed to shorten to 4-6 hrs(4). Vapor-phase benzene is also degraded in the atmosphere by atmospheric ozone radicals at an extremely slow rate; the half-life for this reaction in air is estimated to be 170,000 days(5). The reaction rate of benzene with nitrate radical in the atmosphere is estimated to be less than 0.3X10-16 cu cm/molecule sec at 25 °C(3); the half-life for this reaction in air is estimated to be greater than or equal to 111 days based on an average concentration of nitrate radicals of 2.4X10+8 molec/cu cm(6). A half-life of 16.9 days was reported for photolysis of benzene dissolved in deionized water saturated with air exposed to sunlight(7). Due to benzene's high water solubility, it may be removed from the atmosphere by rainfall(8).

AEROBIC: Benzene present at 100 mg/L, reached 40% of its theoretical BOD in 2 weeks using an activated sludge inoculum at 30 mg/L in the Japanese MITI test(1). Benzene reached 24% of its theoretical oxygen demand in a non-acclimated microbial population after 15 days(2). Aerobic biodegradation of benzene was studied in pre-equilibrated soil-water slurry microcosms(3). Using an enriched aerobic bacterial culture, benzene began to degrade 12 hrs after incubation in an aqueous(soil-free) solution with 50% of benzene degrading after 60 hrs and almost complete degradation within 90 hrs. Using a pre-equilibrated soil-water slurry microcosm, benzene did not begin to degrade until 3 days after application and reached complete degradation after about 12 days(3).

AEROBIC: No degradation of benzene as measured by BOD was reported in coarse-filtered (through 1 cm cotton layer) Superior harbor water incubated at 21 °C for 12 days(1). Biodegradation half-lives of 28 and 16 days were reported in die-away tests using groundwater and water from Lester River, Minnesota, respectively; benzene concentration added ranged from 0-3.2 mg/L(2). The half-life in estuarine water was 6 days as measured by radio-labeled C02 produced(3). In a marine ecosystem biodegradation occurred in 2 days after an acclimation period of 2 days and 2 weeks in the summer and spring, respectively, whereas no degradation occurred in winter(4).

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number F005, U019, D018, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.

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.

Biodegradation, incineration: Benzene is biodegradable. Diluted aqueous soln, therefore, are drained into sewage treatment plants and decomposed there by anaerobic bacteria. Solvent mixtures and sludges of higher concn are burnt in special waste incinerators if a recovery process is uneconomical.

This flammable liquid burns with a very smoky flame. Dilution with alcohol or acetone is suggested to minimize smoke. Recommendable methods: Use as boiler fuel, incineration. Not recommendable: Landfill, discharge to sewer.

For more Disposal Methods (Complete) data for BENZENE (31 total), please visit the HSDB record page.

/GUIDE 130: FLAMMABLE LIQUIDS (Non-Polar/Water-Immiscible/Noxious)/ Fire or Explosion: HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames. Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapor explosion hazard indoors, outdoors or in sewers. Those substances designated with a (P) may polymerize explosively when heated or involved in a fire. Runoff to sewer may create fire or explosion hazard. Containers may explode when heated. Many liquids are lighter than water.

/GUIDE 130: FLAMMABLE LIQUIDS (Non-Polar/Water-Immiscible/Noxious)/ Health: May cause toxic effects if inhaled or absorbed through skin. Inhalation or contact with material may irritate or burn skin and eyes. Fire will produce irritating, corrosive and/or toxic gases. Vapors may cause dizziness or suffocation. Runoff from fire control or dilution water may cause pollution.

/GUIDE 130: FLAMMABLE LIQUIDS (Non-Polar/Water-Immiscible/Noxious)/ Public Safety: CALL Emergency Response Telephone Number on Shipping Paper first. If Shipping Paper not available or no answer, refer to appropriate telephone number listed on the inside back cover. As an immediate precautionary measure, isolate spill or leak area for at least 50 meters (150 feet) in all directions. Keep unauthorized personnel away. Stay upwind. Keep out of low areas. Ventilate closed spaces before entering.

/GUIDE 130: FLAMMABLE LIQUIDS (Non-Polar/Water-Immiscible/Noxious)/ Protective Clothing: Wear positive pressure self-contained breathing apparatus (SCBA). Structural firefighters' protective clothing will only provide limited protection.

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

UN 1114; Benzene

IMO 3.2; Benzene

49 081 10; Benzene

No person may /transport,/ offer or accept a hazardous material for transportation in commerce unless that person is registered in conformance ... and the hazardous material is properly classed, described, packaged, marked, labeled, and in condition for shipment as required or authorized by ... /the hazardous materials regulations (49 CFR 171-177)./

The International Air Transport Association (IATA) Dangerous Goods Regulations are published by the IATA Dangerous Goods Board pursuant to IATA Resolutions 618 and 619 and constitute a manual of industry carrier regulations to be followed by all IATA Member airlines when transporting hazardous materials.

The International Maritime Dangerous Goods Code lays down basic principles for transporting hazardous chemicals. Detailed recommendations for individual substances and a number of recommendations for good practice are included in the classes dealing with such substances. A general index of technical names has also been compiled. This index should always be consulted when attempting to locate the appropriate procedures to be used when shipping any substance or article.

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/

Flammable Liquid

Do not transport with food and feedstuffs.

Symbol: F, T; R: 45-46-11-36/38-48/23/24/25-65; S: 53-45; Note: E

UN Hazard Class: 3; UN Pack Group: II