Isoprene

H224: Extremely flammable liquid and vapor [Danger Flammable liquids]

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

H350: May cause cancer [Danger Carcinogenicity]

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

P203, P210, P233, P240, P241, P242, P243, P273, P280, P303+P361+P353, P318, 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% (1 of 2428) of reports.

H224 (> 99.9%): Extremely flammable liquid and vapor [Danger Flammable liquids]

H341 (> 99.9%): Suspected of causing genetic defects [Warning Germ cell mutagenicity]

H350 (> 99.9%): May cause cancer [Danger Carcinogenicity]

H412 (91.1%): Harmful to aquatic life with long lasting effects [Hazardous to the aquatic environment, long-term hazard]

Aggregated GHS information provided per 2428 reports by companies from 19 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Reported as not meeting GHS hazard criteria per 1 of 2428 reports by companies.

There are 18 notifications provided by 2427 of 2428 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.

This chemical does not meet GHS hazard criteria for 33.8% (49 of 145) of reports.

H317 (65.5%): May cause an allergic skin reaction [Warning Sensitization, Skin]

H334 (57.9%): May cause allergy or asthma symptoms or breathing difficulties if inhaled [Danger Sensitization, respiratory]

P233, P260, P261, P271, P272, P280, P284, P302+P352, P304+P340, P321, P333+P317, P342+P316, P362+P364, P403, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 145 reports by companies from 6 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Reported as not meeting GHS hazard criteria per 49 of 145 reports by companies.

There are 5 notifications provided by 96 of 145 reports by companies with hazard statement code(s).

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

H317: May cause an allergic skin reaction [Warning Sensitization, Skin]

H334: May cause allergy or asthma symptoms or breathing difficulties if inhaled [Danger Sensitization, respiratory]

P233, P260, P261, P264, P271, P272, P280, P284, P302+P352, P304+P340, P321, P332+P317, P333+P317, P342+P316, P362+P364, P403, and P501 (click each P-code to see the statement)

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

H320: Causes eye irritation [Warning Serious eye damage/eye irritation]

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]

H351: Suspected of causing cancer [Warning Carcinogenicity]

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, P303+P361+P353, P304+P340, P305+P351+P338, P318, P319, P331, P337+P317, P370+P378, P391, P403+P233, P403+P235, P405, and P501 (click each P-code to see the statement)

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

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

H316: Causes mild skin irritation [Warning Skin corrosion/irritation]

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

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

H361fd: Suspected of damaging fertility; Suspected of damaging the unborn child [Warning Reproductive toxicity]

Fresh air, rest. Refer for medical attention.

Rinse skin with plenty of water or shower. Remove contaminated clothes. 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. 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. If symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop, call a physician and be prepared to transport the victim to a hospital. 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. (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.

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

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

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

Advice for firefighters: Wear self-contained breathing apparatus for firefighting if necessary.

Use water spray to cool unopened containers.

Use fine spray or fog to control fire by preventing its spread and absorbing some of its heat. Use water spray to keep fire-exposed containers cool. Fight fire from protected location or maximum possible distance.

For more Fire Fighting Procedures (Complete) data for Isoprene (6 total), please visit the HSDB record page.

The vapor is heavier than air and may travel along the ground; distant ignition possible. As a result of flow, agitation, etc., electrostatic charges can be generated. Vapours are uninhibited and may polymerize in vents or flame arresters, causing blockage.

If it becomes contaminated or is subjected to heat, isoprene may polymerize. If the polymerization takes place in a container, the container is subject to violent rupture.

Flashback along vapor trail may occur.

Containers may explode in fire. Vapor may explode if ignited in an enclosed area.

· 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); polymerization hazard]:

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.

Evacuate danger area! Consult an expert! Remove all ignition sources. 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 liquid in sealable containers. Cover the spilled material with inert absorbent. Then store and dispose of according to local regulations.

ACCIDENTAL RELEASE MEASURES: Personal precautions, protective equipment and emergency procedures: Wear respiratory protection. Avoid breathing vapors, mist or gas. Ensure adequate ventilation. Remove all sources of ignition. Evacuate personnel to safe areas. Beware of vapors accumulating to form explosive concentrations. Vapors can accumulate in low areas. Environmental precautions: Prevent further leakage or spillage if safe to do so. Do not let product enter drains. Discharge into the environment must be avoided. Methods and materials for containment and cleaning up: Contain spillage, and then collect with an electrically protected vacuum cleaner or by wet-brushing and place in container for disposal according to local regulations.

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 POTW is acceptable only after review by the governing authority. 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 meet Hazardous Material Criteria for disposal.

Eliminate all ignition sources. Stop or control the leak, if this can be done without undue risk. Use appropriate foam to blanket release and suppress vapors. Absorb in noncombustible material for proper disposal.

Environmental considerations: Land spill. Dig a pit, pond, lagoon, holding area to contain liquid or solid material. /SRP: If time permits, pits, ponds, lagoons, soak holes, or holding areas should be sealed with an impermeable flexible membrane liner./ Dike surface flow using soil, sand bags, foamed polyurethane, or foamed concrete. Absorb bulk liquid with fly ash, cement powder, or commercial sorbents. Apply universal gelling agent to immobilize spill.

For more Cleanup Methods (Complete) data for Isoprene (7 total), please visit the HSDB record page.

SRP: Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in air, soil or water; effects on animal, aquatic and plant life; and conformance with environmental and public health regulations. If it is possible or reasonable use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination.

Product: Burn in a chemical incinerator equipped with an afterburner and scrubber but exert extra care in igniting as this material is highly flammable. Offer surplus and non-recyclable solutions to a licensed disposal company. Contact a licensed professional waste disposal service to dispose of this material; Contaminated packaging: Dispose of as unused product.

Isoprene is a waste chemical stream constituent which may be subjected to ultimate disposal by controlled incineration.

Evaporation & incineration: This material may be evaporated in hood or can be incinerated.

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

SRP: At the time of review, criteria for land treatment or burial (sanitary landfill) disposal practices are subject to significant revision. Prior to implementing land disposal of waste residue (including waste sludge), consult with environmental regulatory agencies for guidance on acceptable disposal practices.

ACCIDENTAL RELEASE MEASURES: Personal precautions, protective equipment and emergency procedures: Wear respiratory protection. Avoid breathing vapors, mist or gas. Ensure adequate ventilation. Remove all sources of ignition. Evacuate personnel to safe areas. Beware of vapors accumulating to form explosive concentrations. Vapors can accumulate in low areas. Environmental precautions: Prevent further leakage or spillage if safe to do so. Do not let product enter drains. Discharge into the environment must be avoided.

Precautions for safe handling: Avoid contact with skin and eyes. Avoid inhalation of vapor or mist. Use explosion-proof equipment. Keep away from sources of ignition - No smoking. Take measures to prevent the build up of electrostatic charge.

Appropriate engineering controls: Handle in accordance with good industrial hygiene and safety practice. Wash hands before breaks and at the end of workday.

Gloves must be inspected prior to use. Use proper glove removal technique (without touching glove's outer surface) to avoid skin contact with this product. Dispose of contaminated gloves after use in accordance with applicable laws and good laboratory practices. Wash and dry hands.

For more Preventive Measures (Complete) data for Isoprene (17 total), please visit the HSDB record page.

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

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 combustible substances, reducing agents, strong oxidants, strong bases, strong acids, alcohols and acid chlorides. Cool. Keep in the dark. Well closed. Store only if stabilized. Provision to contain effluent from fire extinguishing. Store in an area without drain or sewer access.

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. Recommended storage temperature 2 - 8 °C.

Store in a cool, dry well-ventilated location. Outside or detached storage is preferred. Separate from oxidizing materials.

... Before entering confined space where hexanol may be present, check to make sure that an explosive concentration does not exist. Isoprene must be stored to avoid contact with strong acids (such as chlorosulfonic, sulfuric, and nitric) since violent reactions occur. Store in tightly closed containers in a cool, well-ventillated area away from heat, flame and oxidizers. Sources of ignition, such as smoking and open flames, are prohibited where isoprene is handled, used or stored. Metal containers involving the transfer of 5 gallons or more of isoprene should be grounded and bonded. Drums must be eqipped with self-closing valves, pressure vacuum bungs, and flame arresters. Use only non-sparking tools and equipment especially when opening and closing containers of isoprene. Whenever isoprene is used, handled, manufactured, or stored, use explosion-proof electrical equipment and fittings.

PRECAUTIONS FOR "CARCINOGENS": Storage site should be as close as practical 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/

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

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

3.0 [ppm]

5.0 [ppm]

1000 [ppm]

4000 [ppm]

8.5 mg/m

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.

ERPG-1: 5 ppm - one hour exposure limit: 1 = mild transient health effects or objectionable odor [AIHA]

ERPG-2: 1,000 ppm - one hour exposure limit: 2 = impaired ability to take protective action [AIHA]

ERPG-3: 4,000 ppm - one hour exposure limit: 3 = life threatening health effects [AIHA]

Emergency Response Planning Guidlines (ERPGs) for isoprene:[Table#1730]

Russia: 40 mg/cu m

Workplace Environmental Exposure Level (WEEL): 8-hr Time-weighted Average (TWA) 2 ppm. Last Revised: 2004.

A harmful contamination of the air can be reached very quickly on evaporation of this substance at 20 °C.

The substance and the vapour are moderately irritating to the eyes, skin and respiratory tract. The substance may cause effects on the central nervous system. This may result in respiratory depression and lowering of consciousness. If swallowed the substance easily enters the airways and could result in aspiration pneumonitis.

Repeated or prolonged inhalation may cause effects on the lungs. This substance is possibly carcinogenic to humans. May cause heritable genetic damage to human germ cells.

Vapor-proof goggles; self-contained breathing apparatus; leather or rubber safety shoes; rubber gloves. (USCG, 1999)

Eye/face protection: Face shield and safety glasses. Use equipment for eye protection tested and approved under appropriate government standards such as NIOSH (US) or EN 166(EU).

Skin protection: Handle with gloves.

Body Protection: Complete suit protecting against chemicals. Flame retardant antistatic protective clothing. The type of protective equipment must be selected according to the concentration and amount of the dangerous substance at the specific workplace.

Respiratory protection: Where risk assessment shows air-purifying respirators are appropriate use a full-face respirator with multipurpose combination (US) or type AXBEK (EN 14387) respirator cartridges as a backup to engineering controls. If the respirator is the sole means of protection, use a full-face supplied air respirator. Use respirators and components tested and approved under appropriate government standards such as NIOSH (US) or CEN (EU).

For more Personal Protective Equipment (PPE) (Complete) data for Isoprene (6 total), please visit the HSDB record page.

NO open flames, NO sparks and NO smoking. Closed system, ventilation, explosion-proof electrical equipment and lighting. Prevent build-up of electrostatic charges (e.g., by grounding). Do NOT use compressed air for filling, discharging, or handling.

PREVENT GENERATION OF MISTS! STRICT HYGIENE!

Use ventilation. Use local exhaust or breathing protection.

Protective gloves.

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

Isoprene, stabilized appears as a clear colorless liquid with a petroleum-like odor. Density 5.7 lb / gal. Flash point -65 °F. Boiling point 93 °F. May polymerize exothermically if heated or contaminated. If polymerization takes place inside a closed container, the container may rupture violently. Less dense than water and insoluble in water. Vapors heavier than air.

Liquid; Other Solid

Colorless liquid with a mild, aromatic odor; [HSDB]

VERY VOLATILE COLOURLESS LIQUID WITH CHARACTERISTIC ODOUR.

Colorless volatile liquid

Colorless, watery liquid

Nearly colorless and transparent in thin layers.

Amorphous when unstretched, but has oriented crystalline structure on stretching /Cured (unvulcanized)/

Petroleum-lke

Odorless

Tasteless

93 °F at 760 mmHg (NTP, 1992)

34.067 °C

34 °C @760 [mm Hg]

-184 °F (NTP, 1992)

-145.95 °C

The generally accepted crystal melting temperature of natural rubber is 30 °C.

-146.7 °C

-65 °F (NTP, 1992)

-65 °F (-54 °C) (Closed cup)

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

In water, 642 mg/L at 25 °C

Practically insoluble in water

Miscible with ethanol, ethyl ether, acetone, benzene

Soluble in alcohol, ether, hydrocarbon solvents

Natural rubber is soluble in most aliphatic, aromatic, and chlorinated solvents, but its high molecular weight makes it difficult to dissolve.

Practically insol in water, alcohol, dil acids, or alkali; sol in abs ether, chloroform, most fixed or volatile oils, petroleum ether, carbon disulfide, oil of turpentine.

Raw rubber dissolves (or at least swells very strongly) in many organic liquids such as benzene, petroleum ether, crude petroleum, and carbon tetrachloride. In contrast, vulcanized rubber can only swell because the chemical cross-liking prevents dissolution.

Solubility in water, mg/l at 25 °C: 642 (very poor)

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

0.679 g/cu cm at 20 °C

0.906-0.916 g/cu cm @ 20 °C

Relative density (water = 1): 0.7

0.679 @ 20°C

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

2.35 (Air = 1)

(Air= 1)

Relative vapor density (air = 1): 2.4

400 mmHg at 59.7 °F ; 493 mmHg at 68 °F (NTP, 1992)

550.0 [mmHg]

Highly flammable. Insoluble in water.

Hydrocarbons, Aliphatic Unsaturated

Conjugated Dienes

Polymerizable Compounds

Highly Flammable

Polymerizable

Peroxidizable Compound

ISOPRENE may react vigorously with strong oxidizing agents. May react exothemically with reducing agents to release hydrogen gas. May undergo exothermic addition polymerization in the presence of various catalysts (such as acids) or initiators. Undergoes autoxidation upon exposure to the air to form explosive peroxides. Mixing isoprene in equal molar portions with any of the following substances in a closed container caused the temperature and pressure to increase: chlorosulfonic acid, nitric acid (70%), oleum, sulfuric acid (90%) [NFPA 1991].

Mixing isoprene and chlorosulfonic acid in a closed container caused the temperature and pressure to increase.

Mixing isoprene and 70% nitric acid in a closed container caused the temperature and pressure to increase.

Mixing isoprene and oleum in a closed container caused the temperature and pressure to increase.

Mixing isoprene and 96% sulfuric acid in a closed container caused the temperature and pressure to increase.

For more Hazardous Reactivities and Incompatibilities (Complete) data for Isoprene (8 total), please visit the HSDB record page.

IDENTIFICATION AND USE: Isoprene is a colorless volatile liquid. It is used in manufacturing butyl rubber, and as copolymer in the production of synthetic elastomers. HUMAN STUDIES: Respiratory irritation is a potential symptom of overexposure. Isoprene may act as a CNS depressant and asphyxiant at high concentrations. Catarrhal inflammation, subtrophic and atrophic processes in the upper respiratory tract, and deterioration of olfaction were noted in isoprene rubber production workers. Prevalence and degree were correlated with increasing length of service. In the comet assay isoprene induced DNA damage in peripheral blood mononuclear cells in the presence of metabolic activation. ANIMAL STUDIES: Exposure of rats of each sex to 0, 438, 875, 1750, 3500 or 7000 ppm isoprene vapors by inhalation for 6 hr a day on 5 days/wk for 2 wk had no effect. In male mice it reduced body weight gain, produced atrophy of the thymus and testis (at 7000 ppm only), olfactory epithelial degeneration, vacuolized liver cytoplasm and forestomach epithelial hyperplasia. In both male and female mice in all exposure groups, there were reductions in erythrocyte numbers, hemoglobin concentration and volume of packed erythrocytes. An exposure-related increased incidence of liver, lung, Harderian gland and forestomach tumors and hemangiosarcomas and histiocytic sarcomas was reported in mice. In rats, exposed males and females had increased incidences of mammary fibroadenomas. The incidence of renal tubule adenomas was increased in treated males. Some animals also had a renal carcinoma. Treated males also had increased incidence of interstitial-cell adenomas of the testis. Isoprene affected ovarian follicles in 21 day old female mice. In male mice, there was reduction of testicular weight by 35% in the animals exposed to 7000 ppm, seminiferous tubular atrophy in 20% of animals studied, reduced epididymal weights, lower spermatid headcounts and concentrations, and reduced sperm motility in the 700 and 7000 ppm groups. In developmental studies, there was no treatment-related effect on the incidence of fetal malformations or variations other than a slight increase in the incidence of reduced vertebral ossification. Isoprene was negative when tested for mutagenicity in the Salmonella/microsome preincubation assay using 5 S. typhimurium strains (TA1535, TA1537, TA97, TA98, & TA100) with and without metabolic activation. Isoprene did not induce either sister chromatid exchanges or chromosomal aberrations in cultures of Chinese hamster ovary cells.

Evaluation: No epidemiological data relevant to the carcinogenicity of isoprene were available. There is sufficient evidence in experimental animals for the carcinogenicity of isoprene. Overall evaluation: Isoprene is possibly carcinogenic to humans (Group 2B).

Isoprene is reasonably anticipated to be a human carcinogen

Isoprene

Group 2B: Possibly carcinogenic to humans

Volume 60: (1994) Some Industrial Chemicals

Volume 71: (1999) Re-evaluation of Some Organic Chemicals, Hydrazine and Hydrogen Peroxide (Part 1, Part 2, Part 3)

TR-486: Toxicology and Carcinogenesis Studies of Isoprene (CASRN 78-79-5) in F344/N Rats (Inhalation Studies) (1999 )

12/10/97

Clear Evidence

Some Evidence

Chemical Not Tested in Species/Sex

Under the conditions of this 2-year inhalation study, there was clear evidence of carcinogenic activity of isoprene in male F344/N rats based on increased incidences of mammary gland fibroadenoma and carcinoma, renal tubule adenoma, and testicular interstitial cell adenoma. There was some evidence of carcinogenic activity of isoprene in female F344/N rats based on increased incidences and multiplicity of mammary gland fibroadenoma. A low incidence of rare brain neoplasms in exposed female rats may have been due to exposure to isoprene.

Exposure to isoprene by inhalation for 2 years resulted in increased incidences of renal tubule hyperplasia and splenic fibrosis in male rats.

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

Cough. Sore throat. Dizziness. Nausea.

Redness.

Abdominal pain. Burning sensation. Further see Inhalation.

Neurotoxin - Acute solvent syndrome

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.

LC50 (rat) = 180,000 mg/m3/4H

LC50 Rat inhalation 180 g/cu m/4 hr

LC50 Mouse inhalation 139 g/cu m/2 hr

LD50 Rat oral 2,043-2,210 mg/kg

LD50 Rat intraperitoneal 1,310-1,470 mg/kg

Healthy young adult subjects (n = 10) underwent chamber exposure /to isoprene/ on separate days to filtered air and to a variable concentration of ozone. Exposures had durations of 130 min that included alternate periods of rest and light treadmill exercise; breath was sampled pre- and postexposure. For six subjects, breath was resampled 19 +/- 1 hr postexposure. Breath samples were concentrated cryogenically and analyzed by capillary gas chromatography. Isoprene output immediately postexposure was significantly reduced by ozone or filtered air (17 and 19%, respectively). These results suggest that exercise alone reduces isoprene levels in breath without an additive ozone effect. However, in the six subjects restudied 19 +/- 1 hr postexposure to ozone, breath isoprene concentrations were now increased above the preexposure output by 99% (P < 0.01) and exceeded the 51% increase in output of isoprene at this time point after filtered-air exposure (P < 0.01)...

Immediate first aid: Ensure that adequate decontamination has been carried out. If patient is not breathing, start artificial respiration, preferably with a demand valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR if necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on the left side (head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Aliphatic hydrocarbons and related compounds/

Basic treatment: Establish a patent airway (oropharyngeal or nasopharyngeal airway, if needed). Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if necessary. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . Anticipate seizures and treat if necessary ... . For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with 0.9% saline (NS) during transport ... . Do not use emetics. For ingestion, rinse mouth and administer 5 mL/kg up to 200 mL of water for dilution if the patient can swallow, has a strong gag reflex, and does not drool. Administer activated charcoal ... . Treat frostbite with rapid rewarming techniques ... . /Aliphatic hydrocarbons and related compounds/

Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in severe respiratory distress. Positive-pressure ventilation techniques with a bag-valve-mask device may be beneficial. Consider drug therapy for pulmonary edema ... . Monitor cardiac rhythm and treat arrhythmias as necessary ... . Start IV administration of D5W /SRP: "To keep open", minimal flow rate/. Use 0.9% saline (NS) or lactated Ringer's (LR) if signs of hypovolemia are present. For hypotension with signs of hypovolemia, administer fluid cautiously. Watch for signs of fluid overload ... . Treat seizures with diazepam (Valium) or lorazepam (Ativan) ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Aliphatic hydrocarbons and related compounds/

No data for EMT.

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/

/HUMAN EXPOSURE STUDIES/ Healthy young adult subjects (n = 10) underwent chamber exposure /to isoprene/ on separate days to filtered air and to a variable concentration of ozone. Exposures had durations of 130 min that included alternate periods of rest and light treadmill exercise; breath was sampled pre- and postexposure. For six subjects, breath was resampled 19 +/- 1 hr postexposure. Breath samples were concentrated cryogenically and analyzed by capillary gas chromatography. Isoprene output immediately postexposure was significantly reduced by ozone or filtered air (17 and 19%, respectively). These results suggest that exercise alone reduces isoprene levels in breath without an additive ozone effect. However, in the six subjects restudied 19 +/- 1 hr postexposure to ozone, breath isoprene concentrations were now increased above the preexposure output by 99% (P < 0.01) and exceeded the 51% increase in output of isoprene at this time point after filtered-air exposure (P < 0.01)...

/HUMAN EXPOSURE STUDIES/ In 10 human volunteers, the average odor perception occurred at 10 mg/cu m, and at 160 mg/cu m they experienced slight irritation of the upper respiratory mucosa, larynx, and pharynx.

/SIGNS AND SYMPTOMS/ Catarrhal inflammation, subtrophic & atrophic processes in the upper respiratory tract, & deterioration of olfaction were noted in isoprene rubber production workers. Prevalence & degree were correlated with increasing length of service.

/GENOTOXICITY/ Isoprene ... is a petrochemical and a natural product being primarily produced by plants. It is biotransformed to 2-ethenyl-2-methyloxirane (IP-1,2-O) and 2-(1-methylethenyl)oxirane (IP-3,4-O), both of which can be further metabolized to 2-methyl-2,2'-bioxirane (MBO). MBO is mutagenic, but IP-1,2-O and IP-3,4-O are not. While IP-1,2-O has been reported being genotoxic, the genotoxicity of IP-3,4-O and MBO, and the cross-linking potential of MBO have not been examined. In the present study, we used the comet assay to investigate the concentration- and time-dependent genotoxicity profiles of the three metabolites and the cross-linking potential of MBO in human hepatocyte L02 cells. For the incubation time of 1 hr, all metabolites showed positive concentration-dependent profiles with a potency rank order of IP-3,4-O > MBO > IP-1,2-O. In human hepatocellular carcinoma (HepG2) and human leukemia (HL60) cells, IP-3,4-O was still more potent in inducing DNA breaks than MBO at high concentrations (>200 uM), although at low concentrations (=200 uM) IP-3,4-O exhibited slightly lower or similar potency to MBO. Interestingly, their time-dependent genotoxicity profiles (0.5-4 hr) in L02 cells were different from each other: IP-1,2-O and MBO (200 uM) exhibited negative and positive profiles, respectively, with IP-3,4-O lying in between, namely, IP-3,4-O-caused DNA breaks did not change over the exposure time. Further experiments demonstrated that hydrolysis of IP-1,2-O contributed to the negative profile and MBO induced cross-links at high concentrations and long incubation times. Collectively, the results suggested that IP-3,4-O might play a significant role in the toxicity of isoprene. /Isoprene metabolites/

For more Human Toxicity Excerpts (Complete) data for Isoprene (7 total), please visit the HSDB record page.

Rubber latex is a primary skin irritant and sensitizer, and causes local irritation when ingested. /Rubber latex/

Rubber foreign bodies in the anterior chamber of patients after operation were described ... 7 cases in which tiny red particles came from the inner surface of red rubber irrigating bulbs, and lodged in crypts of the iris, or attached to hyaloid membrane or cornea. Although some of the eyes had a period of postoperative inflammation, this did not seem to involve the particles, and the particles did not seem to disturb the tissues with which they were in contact. /Rubber foreign bodies/

Severe anaphylactic reaction secondary to latex allergy has lately been recognized and reported especially in individuals with spina bifida. We report a case of severe intraoperative anaphylactic reaction due to latex allergy. Preoperative testing for latex allergy may be helpful in determining latex allergy. We suggest preoperative management protocol for patients who are thought to have latex allergy. An increased awareness to latex allergy will help avoid this potentially castastrophic event.

LC50; Species: Carassius auratus (Goldfish) length 3.8-6.4 cm, weight 1-2 g; Conditions: freshwater, static, 25 °C, pH 7.5, hardness 20 mg/L CaCO3, alkalinity 18 mg/L CaCO3, dissolved oxygen 7.8 mg/L; Concentration: 180000 ug/L for 24 hr (95% confidence interval: 150410-215410 ug/L) /formulated product/

LC50; Species: Carassius auratus (Goldfish) length 3.8-6.4 cm, weight 1-2 g; Conditions: freshwater, static, 25 °C, pH 7.5, hardness 20 mg/L CaCO3, alkalinity 18 mg/L CaCO3, dissolved oxygen 7.8 mg/L; Concentration: 180000 ug/L for 48 hr (95% confidence interval: 150410-215410 ug/L) /formulated product/

LC50; Species: Carassius auratus (Goldfish) length 3.8-6.4 cm, weight 1-2 g; Conditions: freshwater, static, 25 °C, pH 7.5, hardness 20 mg/L CaCO3, alkalinity 18 mg/L CaCO3, dissolved oxygen 7.8 mg/L; Concentration: 180000 ug/L for 96 hr (95% confidence interval: 150410-215410 ug/L) /formulated product/

LC50; Species: Lepomis macrochirus (Bluegill) length 3.8-6.4 cm, weight 1-2 g; Conditions: freshwater, static, 25 °C, pH 7.5, hardness 20 mg/L CaCO3, alkalinity 18 mg/L CaCO3, dissolved oxygen 7.8 mg/L; Concentration: 42540 ug/L for 24 hr (95% confidence interval: 32500-50150 ug/L) /formulated product/

For more Ecotoxicity Values (Complete) data for Isoprene (34 total), please visit the HSDB record page.

The substance is toxic to aquatic organisms. It is strongly advised not to let the chemical enter into the environment.

Isoprene's production and use as a monomer in the manufacture of polyisoprene, synthetic rubber, butyl rubber and as a copolymer in the production of synthetic elastomers may result in its release to the environment through various waste streams. Isoprene is a biogenic chemical emitted from several tree and plant species and has been detected in emissions occurring at the surface of ocean water. Isoprene was found to be the main endogenous hydrocarbon of human breath. If released to air, a vapor pressure of 550 mm Hg at 25 °C indicates isoprene will exist solely as a vapor in the atmosphere. Vapor-phase isoprene will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals, ozone, and nitrate radicals; the half-lives for these reactions in air are estimated to be 3.8, 19, and 1.2 hours, respectively. Isoprene absorbs light with a UV maximum of approximately 237 nm and, therefore, is not expected to be susceptible to direct photolysis by sunlight since sunlight consists of wavelengths greater than 290 nm. If released to soil, isoprene is expected to have high mobility based upon an estimated Koc of 125. Volatilization from moist soil surfaces is expected to be an important fate process based upon an estimated Henry's Law constant of 7.7X10-2 atm-cu m/mole. Isoprene is expected to volatilize from dry soil surfaces based upon its vapor pressure. Utilizing the Closed Bottle and Manometric Respirometry Tests, 60% and 53-75% of theoretical BOD, respectively was reached in 4 weeks indicating that biodegradation is an important environmental fate process soil and water. If released into water, isoprene is not expected to adsorb to suspended solids and sediment based upon the estimated Koc. Volatilization from water surfaces is expected to be an important fate process based upon this compound's estimated Henry's Law constant. Estimated volatilization half-lives for a model river and model lake are 2.4 hours and 3.3 days, respectively. A BCF range of <5.6-20 suggests bioconcentration in aquatic organisms is low. Hydrolysis is not expected to be an important environmental fate process since this compound lacks functional groups that hydrolyze under environmental conditions (pH 5 to 9). Occupational exposure to isoprene may occur through inhalation and dermal contact with this compound at workplaces where isoprene is produced or used. Monitoring data indicate that the general population may be exposed to isoprene via inhalation of ambient air, inhalation of tobacco smoke, ingestion of food, and dermal contact with essential oils and consumer products containing isoprene. (SRC)

Isoprene is a constituent of the volatile emissions from several tree and plant species(1-5). Isoprene has been identified as a constituent in root and fruit tissues, and essential oils of several plant species(6). Studies have indicated that oak trees are the principal source for natural emissions of isoprene to the atmosphere(1,2). Isoprene has been detected in oceanic emissions of superficial ocean water where its production is a result of biological processes in marine ecosystems(7,8). Isoprene was found to be the main endogenous hydrocarbon of human breath(9).

Isoprene is formed endogenously at the rate of 1.9 umol/kg per hour in both rats and mice.

Isoprene's production and use as a monomer in the manufacture of polyisoprene, synthetic rubber, butyl rubber and as a copolymer in production of synthetic elastomers(1,2) may result in its release to the environment through various waste streams(SRC). Isoprene has been identified as a constituent of tobacco, tobacco smoke, and tobacco substitute smoke(3).

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 125(SRC), determined from a log Kow of 2.42(2) and a regression-derived equation(3), indicates that isoprene is expected to have high mobility in soil(SRC). Volatilization of isoprene from moist soil surfaces is expected to be an important fate process(SRC) given an estimated Henry's Law constant of 7.7X10-2 atm-cu m/mole(SRC) derived from its vapor pressure, 550 mm Hg(4), and water solubility, 642 mg/L(5). Isoprene is expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(4). A 60% of theoretical BOD using an adapted domestic sewage sludge in the Closed Bottle test and 53-75% of theoretical BOD in 4 weeks using an activated sludge inoculum in the Manometric Respirometry Test(6), suggests that biodegradation is an important environmental fate process in soil(SRC).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 125(SRC), determined from a log Kow of 2.42(2) and a regression-derived equation(3), indicates that isoprene is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(4) based upon an estimated Henry's Law constant of 7.7X10-2 atm-cu m/mole(SRC) derived from its vapor pressure, 550 mm Hg(5), and water solubility, 642 mg/L(6). Using this Henry's Law constant and an estimation method(4), volatilization half-lives for a model river and model lake are 2.4 hours and 3.3 days, respectively(SRC). According to a classification scheme(7), a BCF range of <5.6-20 measured in carp(8), suggests the potential for bioconcentration in aquatic organisms is low(SRC). A 60% of theoretical BOD using an adapted domestic sewage sludge in the Closed Bottle test and 53-75% of theoretical BOD in 4 weeks using an activated sludge inoculum in the Manometric Respirometry Test(9), suggests that biodegradation is an important environmental fate process in water(SRC).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), isoprene, which has a vapor pressure of 550 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase isoprene 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 3.8 hours(SRC), calculated from its rate constant of 1.01X10-10 cu cm/molecule-sec at 25 °C(3). Isoprene will also be degraded in the atmosphere by reaction with ozone and nitrate radical, the reaction half-lives for these reactions are 19 and 1.2 hours, calculated from reaction rates of 1.43X10-17 cu cm/molecule-sec(4) and 2.4X10+8 nitrate radicals per cu cm(5), respectively. Isoprene absorbs light with a UV maximum of approximately 237 nm(6) and, therefore, is not expected to be susceptible to direct photolysis by sunlight since sunlight consists of wavelengths greater than 290 nm(SRC).

AEROBIC: The half-life of isoprene, present at 500 ppb, was approximately 6 hours at 25-30 °C, using 30 gram temperate forest soil samples from Ithaca, NY; degradation was found to be temperature dependent and the rate of degradation was slower in subsurface soils (9-12 cm depth) than in surface soil (0-3 cm depth) samples(1).

AEROBIC: Isoprene, present at 2 mg/L, reached 2% of its theoretical BOD in 4 weeks using an activated sludge inoculum at 1 drop/L in the Japanese Miti test(1). Isoprene present at 51 mg/L, with an added inhibitor, reached 53-75% of its theoretical BOD in 4 weeks using an activated sludge inoculum in 3 replicate studies using the Manometric Respirometry Test, the 10-day window for ready biodegradability was not met(2,3). Isoprene, present at 2 mg/L, reached 60% of its theoretical BOD in 4 weeks using an adapted domestic sewage inoculum in the Closed Bottle Test(2,3).

PURE CULTURE: Nocardia sp. was able to degrade isoprene and use this compound as a sole energy source; however it is not clear what the rate of biodegradation was under environmental conditions(1).

The rate constant for the vapor-phase reaction of isoprene with photochemically-produced hydroxyl radicals has been estimated as 1.01X10-10 cu cm/molecule-sec at 25 °C(1). This corresponds to an atmospheric half-life of about 3.8 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). The rate constant for the vapor-phase reaction of isoprene with ozone is 1.43X10-17 cu cm/molecule-sec at 25 °C(2). This corresponds to an atmospheric half-life of about 19 hours at an atmospheric concentration of 7X10+11 ozone molecules per cu cm(2). The rate constant for the vapor-phase reaction of isoprene with nitrate radicals is 6.78X10-13 cu cm/molecule-sec at 25 °C(3). This corresponds to an atmospheric half-life of about 1.2 hours at an atmospheric concentration of 2.4X10+8 nitrate radicals per cu cm(4). Based on experimental data for the reaction of isoprene with nitrate radicals, the lifetime for isoprene at nighttime can be estimated to be 216 min and 22 min under clean and moderately polluted atmospheric conditions, respectively(5). Isoprene is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(6). Isoprene absorbs light with a UV maximum of approximately 237 nm(7) and therefore is not expected to be susceptible to direct photolysis by sunlight since sunlight consists of wavelengths above 290 nm(SRC).

BCFs of 5-14 and <5.8-20 were measured in carp (Cyprinus carpio) exposed to 50 and 5 ug/L of isoprene over a 6-week period(1). According to a classification scheme(2), these BCFs suggest bioconcentration in aquatic organisms is low(SRC).

The Koc of isoprene is estimated as 125(SRC), using a log Kow of 2.42(1) and a regression-derived equation(2). According to a classification scheme(3), this estimated Koc value suggests that isoprene is expected to have high mobility in soil.

The Henry's Law constant for isoprene is estimated as 7.7X10-2 atm-cu m/mole(SRC) derived from its vapor pressure, 550 mm Hg(1), and water solubility, 642 mg/L(2). This Henry's Law constant indicates that isoprene is expected to volatilize rapidly from water surfaces(3). Based on this Henry's Law constant, the volatilization half-life from a model river (1 m deep, flowing 1 m/sec, wind velocity of 3 m/sec)(3) is estimated as 2.4 hours(SRC). The volatilization half-life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec)(3) is estimated as 3.3 days(SRC). Isoprene's estimated Henry's Law constant indicates that volatilization from moist soil surfaces may occur(SRC). The potential for volatilization of isoprene from dry soil surfaces may exist based upon its vapor pressure(1).

SEAWATER: Based on data obtained in the Mediterranean Sea and Pacific Ocean in May 1987, isoprene concentration in superficial seawater is in the range of 1.0X10-9 liter of gas per liter of water; with an estimated oceanic flux into the atmosphere of 1.2 million tons per year(1). Isoprene was detected at concentrations ranging from 1.12-66.38 pmol/L (Mean range 4.40-26.76 pmol/L) in the Arctic and Atlantic oceans in July/August 2013 and October/November 2013, respectively(2). Isoprene concentrations in surface seawater ranged from 32.46 to 173.5 pM, with an average of 83.62 pM in samples collected from East China Sea and the South Yellow Sea in July 2013(3).

SEAWATER: Isoprene has been detected in ocean waters(1) Literature review highlights concentrations but does not specify year of analysis(SRC).[Table#1740]

Isoprene has been detected in wood stove and fireplace emissions at concentrations ranging from 0.003 to 0.106 ppb(1). In another study, it was detected at a concentration of 7 ppb in woodsmoke(2). Isoprene has been detected at a concentration of 0.46 mg/cu m from an atmospheric grab sample taken near an oil fire(3). Isoprene has been detected in 5 of 10 samples in the exhaust of turbojet engines at concentrations of 19.8, 18.1, 0.14, 0.20, and 0.05 ppm(4). Isoprene was released as fireplace emissions at 38.74 and 27.04 mg/kg of fuel burnt for soft and hard wood, respectively(5). Isoprene was found in emissions from a wood stove using hardwood at 43.25 mg/kg of fuel burnt and using synthetic fuel at 4.36 mg/kg of fuel burnt(5). Isoprene was measured in the emissions of burnt pine at 41.0 mg/kg but not detected in the emissions of burnt oak or eucalyptus(6). Isoprene was measured in the Tegal tunnel, Berlin at 0.0043% of total exhaust gases(7).

URBAN/SUBURBAN: Isoprene has been detected in five air samples collected in Houston, TX on April 2, 1974 at concentrations ranging from 5.2 to 74.3 ppb(1). Isoprene has been detected at concentrations of 1.2 and 1.0 ppb in two air samples taken from the suburbs of Tulsa, OK and a concentration of 0.3 ppb in air samples taken from both rural and downtown Tulsa, OK on July 27, 1978(2). Isoprene was detected at a mean concentration of 1.1 ug/cu m around the Los Angeles, CA area during a smog event on September 8-9, 1993(3). Isoprene was detected in 1, 2, and 3% of samples taken in May-Nung, Ping-Tung, and Chao-Chou, Taiwan, respectively(4). Isoprene was measured in ambient air in Southern Taiwan from January 1998 to April 1998: not detected in Hsinghua, not detected to 5.8 ug/cu m in Chao-Chou, not reported in Chiaotou and Meinong(5). Isoprene was detected at 0.78, 0.24, and 0.33 ug/cu m in Frohnau, Nansenstrasze, and Frankfurter Allea, respectively, in Berlin, Germany from samples taken Jun-Aug 1996(6).

INDOOR AIR: The median isoprene concentration in 22 homes in Ontario, Canada in which at least one member of the household smoked was 4.2 ug/cu m, while the median concentration in smoke-free homes was 1.8 ug/cu m(1). Isoprene was detected in the indoor air of 6 office buildings in Greece at concentrations of about 1-4 ug/cu m(2). Indoor isoprene concentrations of 60 non-smoking residence, 29 smoking residence, 51 non-smoking work places, and 28 smoking work places were 0.99-17.27, 2.86-68.02, 0-19.65, and 1.02-61.18 ug/cu m, respectively, samples taken in Eastern PA and Western NJ(3).

RURAL/REMOTE: Isoprene was detected at a concentration of approximately 2.3 ppb at a distance of about 0.25 km above the tropical rain forest of Guyana; however, no isoprene was detected 2-km above the rain forest(1). Isoprene has been detected at concentrations of approximately 2.7, 2.75, 1.5, 2.5 and 2.55 ppb above the Guyana rain forest at distances about 370, 343, 300, 270, 218 km, respectively, from the Atlantic ocean; however, concentrations fall to undetectable over the ocean(1). Isoprene was detected in 5 of 6 samples taken in the ambient air of Rio Blanco County, CO on July 24 and 25, 1978 at concentrations ranging from 0.1-5.6 ppb(2). Isoprene has been detected at concentrations of 4.2, 3.5, 5.7, 4.9, 0.7 and 3.6 ppb in 7 of 9 samples taken from the Smokey Mountains in Tennessee on September 25 and 26, 1978(2). Isoprene has been detected at concentrations of 1.2 and 0.4 ppb in the ambient air above Jones State Forest north of Houston, TX in January 1978(3). The average daily outdoor concentration for isoprene was reported as 0.608 ppb(4). Isoprene has been detected at concentrations ranging from 0.1-13.4 ppb in air samples taken from six locations in northwestern North Carolina from September 1981 to October 1982(5). In a 1-month field study examining ambient gaseous hydrocarbons in the mountains of the Georgian Republic of the USSR in July 1979, isoprene was detected at 7-30 ppb(6). Isoprene was detected in the Balbina forest, Amazonia in samples taken March and April 1998 at concentrations of 2-10 ppb(7). Isoprene was found in Taenikon, Switzerland throughout 1997 at concentrations of 0.1-0.15 ppb, 0-0.1 ppb are believed to be from biogenic sources(8). Samples taken July 6-8, 2000 in Tapajos, Brazil had maximum concentrations of isoprene of 5 ppb(9). Isoprene was detected in 21, 24, and 11% of the total biogenic emissions in Valley, Middle, and Peak Stations, in samples taken in Achenkirch, Tyrol, Austria, June 14, 1996(10).

SOURCE DOMINATED: Based on data obtained in the Mediterranean Sea and Pacific Ocean in May 1987, isoprene oceanic flux into the atmosphere is estimated at 1.2 million tons per year(1). Isoprene was detected in the Arctic and Atlantic ocean air at concentrations ranging from <DL-18.28 pptv (mean range 1.88-3.37 pptv) in July/August 2013 and October/November 2013, respectively(2). Isoprene sea-to-air fluxes ranged from 22.17 nmol/m sq day to 537.2 nmol/m sq day, with an average of 161.5 nmol/m sq day(3).

Isoprene was detected at a concentration of 3,000 ug/kg of cooked hamburger meat(1). Isoprene was not detected in the emissions from cooking food in a restaurant, tortilleria, rotisserie, fried food or using liquid propane gas in Mexico City, in a study done March 20-31, 1998(2).

Isoprene was identified, not quantified in the leaves of oak trees(1,2). Isoprene was detected in Norway spruce from Asa, Sweden in samples taken May and June 1997(3). Isoprene was detected in the volatile emissions from sunflower plants at a mean emission rate of 30 ng/g (dry weight) per hour(4). Isoprene was detected in the emissions of various plants from California at rates of 5-45 ug/g-hour(5). Isoprene was detected in the volatile emissions of aspen, cottonwood, oak, ponderosa pine, Engelmann spruce and Douglas fir, and three species of eucalyptus (E. citriodora, E. dunni, E. saligna)(6,7).

The emission rate of isoprene from various species of white spruce (Picea. sp) selected from 12 various geographical origins and grown in an arboretum in Rhinelander, WI was 0.01-14 ug/g-hour(1).[Table#1732]

Isoprene was detected in the emissions of several tree species measured during the summer of 1993 in the Fernbank Forest in Atalanta, GA(1).[Table#1733]

Isoprene was detected in the emissions of several plant species measured during the summer of 1993 in Willow Springs, WI(1).[Table#1734]

For more Plant Concentrations (Complete) data for Isoprene (6 total), please visit the HSDB record page.

In a pilot study of pollutants in the milk of women living in 4 urban industrial areas in the USA, isoprene was detected in 1 of 8 samples(1).

Isoprene has been identified as a constituent of tobacco, tobacco smoke, and tobacco substitute smoke(1). Environmental tobacco smoke was analyzed after smoking of research cigarettes by a machine in an experimental chamber 13.6 cu m in volume. The ventilation rate was 3.55 air changes per hr. Air removed for sampling added about 0.5 air changes per hr. One cigarette was lit every 30 min and was smoked with a 35 ml puff of 2 sec every minute until extinguished after about 12 min. Mainstream smoke was vented to the outside of the chamber. Additional tests were performed with one cigarette smoked every 15 min and with several commercial cigarette brands. Isoprene (ug/cu m) was detected in air samples at the following levels: 2 to 11, background; 128, grab samples at peak concentration with smoking 1 cigarette every 30 min; 92, continuous sampling with smoking 1 cigarette every 15 min; 225, continuous sampling with smoking 1 cigarette every 20 min. The average airborne yield for isoprene from cigarette smoke has been estimated to be 3,100 ug/cigarette. Concentration of isoprene using commercial brands of cigarettes in the chamber and in a tavern setting were similar to those produced by the research cigarettes(2). Isoprene was detected in tobacco smoke at a concentration of 360 ug/cu m(3).

Isoprene has been detected in oceanic emissions of superficial ocean water where its production is a result of abiotic and biological processes in marine ecosystems(1,2); estimates of global oceanic emissions from serval studies range from approximately 0.1-1 TgC/yr (teragrams carbon) to 1.68-11.6 TgC/yr(2).

According to the 2016 TSCA Inventory Update Reporting data, 12 reporting facilities estimate the number of persons reasonably likely to be exposed during the manufacturing, processing, or use of isoprene in the United States may be as low as 25 workers and as high as 9,999 workers per plant; the data may be greatly underestimated due to confidential business information (CBI) or unknown values(1).

NIOSH (NOES Survey 1981-1983) has statistically estimated that 3,703 workers (578 of these are female) were potentially exposed to isoprene in the US(1). Occupational exposure to isoprene may occur through inhalation and dermal contact with this compound at workplaces where isoprene is produced or used. Monitoring data indicate that the general population may be exposed to isoprene via inhalation of ambient air, inhalation of tobacco smoke, ingestion of food, and dermal contact with essential oils and consumer products containing isoprene(SRC).

Since 1979 several reports of contact urticaria due to natural latex have been well documented. Recent case reports suggest that rhinitis and asthma may also be due to rubber exposure. An operating room nurse who was exposed at work to natural rubber (latex) due to the use of latex surgical gloves was described. ...

Isoprene intake in individuals with a home and work smoking atmosphere, home smoking and work non-smoking atmosphere, non-smoking home and smoking work atmosphere, and non-smoking home and work atmosphere are (home/work) 9.01/4.92, 9.41/1.15, 2.89/6.96, and 2.39/1.49 ug day/cu m, respectively(1).

SRP: Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in air, soil or water; effects on animal, aquatic and plant life; and conformance with environmental and public health regulations. If it is possible or reasonable use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination.

Product: Burn in a chemical incinerator equipped with an afterburner and scrubber but exert extra care in igniting as this material is highly flammable. Offer surplus and non-recyclable solutions to a licensed disposal company. Contact a licensed professional waste disposal service to dispose of this material; Contaminated packaging: Dispose of as unused product.

Isoprene is a waste chemical stream constituent which may be subjected to ultimate disposal by controlled incineration.

Evaporation & incineration: This material may be evaporated in hood or can be incinerated.

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

SRP: At the time of review, criteria for land treatment or burial (sanitary landfill) disposal practices are subject to significant revision. Prior to implementing land disposal of waste residue (including waste sludge), consult with environmental regulatory agencies for guidance on acceptable disposal practices.

/GUIDE 130P FLAMMABLE LIQUIDS (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. /Isoprene, stabilized/

/GUIDE 130P FLAMMABLE LIQUIDS (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. /Isoprene, stabilized/

/GUIDE 130P FLAMMABLE LIQUIDS (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, uphill and/or upstream. Ventilate closed spaces before entering. /Isoprene, stabilized/

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

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

1218 130P

UN 1218; Isoprene, stabilized

IMO 3; Isoprene, stabilized

IMO 4.1; Rubber scrap, powdered or granulated

UN 1345; Rubber scrap, powdered or granulated

49 072 30; Isoprene

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 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. Isoprene, stabilized is included on the dangerous goods list. /Isoprene, stabilized/

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. Isoprene, stabilized is included on the dangerous goods list. /Isoprene, stabilized/

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/

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.

Flammable Liquid

Unbreakable packaging.

Symbol: F+, T; R: 45-12-68-52/53; S: 53-45-61; Note: D

UN Hazard Class: 3; UN Pack Group: I