Butyric anhydride

This chemical does not meet GHS hazard criteria for 4.8% (21 of 437) of reports.

H302 (63.4%): Harmful if swallowed [Warning Acute toxicity, oral]

H314 (92.7%): Causes severe skin burns and eye damage [Danger Skin corrosion/irritation]

H318 (39.8%): Causes serious eye damage [Danger Serious eye damage/eye irritation]

P260, P264, P264+P265, P270, P280, P301+P317, P301+P330+P331, P302+P361+P354, P304+P340, P305+P354+P338, P316, P317, P321, P330, P363, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 437 reports by companies from 10 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Reported as not meeting GHS hazard criteria per 21 of 437 reports by companies.

There are 9 notifications provided by 416 of 437 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.

H227: Combustible liquid [Warning Flammable liquids]

H314: Causes severe skin burns and eye damage [Danger Skin corrosion/irritation]

H318: Causes serious eye damage [Danger Serious eye damage/eye irritation]

H371: May cause damage to organs [Warning Specific target organ toxicity, single exposure]

P210, P260, P264, P264+P265, P270, P280, P301+P330+P331, P302+P361+P354, P304+P340, P305+P354+P338, P308+P316, P316, P317, P321, P363, P370+P378, P403, P405, and P501 (click each P-code to see the statement)

Excerpt from ERG Guide 156 [Substances - Toxic and/or Corrosive (Combustible / Water-Sensitive)]:

Refer to the "General First Aid" section. Specific First Aid: For corrosives, in case of contact, immediately flush skin or eyes with running water for at least 30 minutes. Additional flushing may be required. Removal of solidified molten material from skin requires medical assistance. (ERG, 2024)

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:

· For corrosives, in case of contact, immediately flush skin or eyes with running water for at least 30 minutes. Additional flushing may be required.

· Removal of solidified molten material from skin requires medical assistance.

In Canada, an Emergency Response Assistance Plan (ERAP) may be required for this product. Please consult the shipping paper and/or the "ERAP" section.

Excerpt from ERG Guide 156 [Substances - Toxic and/or Corrosive (Combustible / Water-Sensitive)]:

Note: Most foams will react with the material and release corrosive/toxic gases. CAUTION: For Acetyl bromide (UN1716), use CO2 or dry chemical only.

SMALL FIRE: CO2, dry chemical, dry sand, alcohol-resistant foam.

LARGE FIRE: Water spray, fog or alcohol-resistant foam. FOR CHLOROSILANES, DO NOT USE WATER; use alcohol-resistant foam. If it can be done safely, move undamaged containers away from the area around the fire. Avoid aiming straight or solid streams directly onto the product.

FIRE INVOLVING TANKS, RAIL TANK CARS OR HIGHWAY TANKS: Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles. Do not get water inside containers. 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. (ERG, 2024)

Use water in flooding quantities as fog. Solid streams of water may be ineffective. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. Use "alcohol" foam, dry chemical or carbon dioxide. Use water spray to knock-down vapors.

... Substance will react with water (some violently) releasing flammable, toxic or corrosive gases and runoff. When heated, vapors may form explosive mixtures with air: indoors, outdoors and sewers explosion hazards. ... Vapors may travel to source of ignition and flash back. Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated or if contaminated with water.

· 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 damaged containers or spilled material unless wearing appropriate protective clothing.

· Stop leak if you can do it without risk.

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

· FOR CHLOROSILANES, use alcohol-resistant foam to reduce vapors.

· DO NOT GET WATER on spilled substance or inside containers.

· Use water spray to reduce vapors or divert vapor cloud drift. Avoid allowing water runoff to contact spilled material.

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

Small Spill

· Cover with DRY earth, DRY sand or other non-combustible material followed with plastic sheet to minimize spreading or contact with rain.

· Use clean, non-sparking tools to collect material and place it into loosely covered plastic containers for later disposal.

Excerpt from ERG Guide 156 [Substances - Toxic and/or Corrosive (Combustible / Water-Sensitive)]:

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

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

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

Immediate precautionary measure

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

· For highlighted materials: see Table 1 - Initial Isolation and Protective Action Distances.

· For non-highlighted materials: increase the immediate precautionary measure distance, in the downwind direction, as necessary.

· 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.

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination. 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 soil or water; effects on animal and plant life; and conformance with environmental and public health regulations.

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.

ADEQUATE VENTILATION SHOULD BE PROVIDED... /ACID ANHYDRIDES/

SRP: Local exhaust ventilation should be applied wherever there is an incidence of point source emissions 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. Ensure that the local ventilation moves the contaminant away from the worker.

Excerpt from ERG Guide 156 [Substances - Toxic and/or Corrosive (Combustible / Water-Sensitive)]:

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 damaged containers or spilled material unless wearing appropriate protective clothing. Stop leak if you can do it without risk. A vapor-suppressing foam may be used to reduce vapors. FOR CHLOROSILANES, use alcohol-resistant foam to reduce vapors. DO NOT GET WATER on spilled substance or inside containers. Use water spray to reduce vapors or divert vapor cloud drift. Avoid allowing water runoff to contact spilled material. Prevent entry into waterways, sewers, basements or confined areas.

SMALL SPILL: Cover with DRY earth, DRY sand or other non-combustible material followed with plastic sheet to minimize spreading or contact with rain. Use clean, non-sparking tools to collect material and place it into loosely covered plastic containers for later disposal. (ERG, 2024)

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

· Wear chemical protective clothing that is specifically recommended by the manufacturer when there is NO RISK OF FIRE.

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

· Note: Most foams will react with the material and release corrosive/toxic gases.

CAUTION: For Acetyl bromide (UN1716), use CO2 or dry chemical only.

Small Fire

· CO2, dry chemical, dry sand, alcohol-resistant foam.

Large Fire

· Water spray, fog or alcohol-resistant foam.

· FOR CHLOROSILANES, DO NOT USE WATER; use alcohol-resistant foam.

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

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

Fire Involving Tanks, Rail Tank Cars or Highway Tanks

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

· Do not get water inside containers.

· 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.

Excerpt from ERG Guide 156 [Substances - Toxic and/or Corrosive (Combustible / Water-Sensitive)]:

Wear positive pressure self-contained breathing apparatus (SCBA). Wear chemical protective clothing that is specifically recommended by the manufacturer when there is NO RISK OF FIRE. Structural firefighters' protective clothing provides thermal protection but only limited chemical protection. (ERG, 2024)

...SUITABLE PERSONAL PROTECTIVE EQUIPMENT...WORN. IN CERTAIN CIRCUMSTANCES, PARTICULARLY THOSE ASSOCIATED WITH MAINTENANCE WORK, SUITABLE EYE PROTECTION EQUIPMENT & RESP PROTECTIVE EQUIPMENT ARE NECESSARY. /ACID ANHYDRIDES/

Butyric anhydride is a water-white liquid with an odor of rancid butter. Corrosive to metals and tissue. Low toxicity.

Water-white liquid; [Hawley] Colorless liquid with a pungent odor; [HSDB] Decomposes in water forming butyric acid; [CHEMINFO]

Water-white liquid

PUNGENT ODOR

180 °F (NFPA, 2010)

180 °F (54 °C) (closed cup)

Soluble in water and alcohol with decomposition; soluble in ether

0.9668 at 20 °C/4 °C

5.4 (Air = 1)

0.28 [mmHg]

0.3 mm Hg at 25 °C

log Kow = 1.39 /estimated; value theoretical due to hydrolysis in water/

535 °F (279 °C)

When headed to decomposition it emits acrid smoke and irritating vapors.

1.59 cP at 20 °C

50 kJ/mol at bp

0.02884 N/m at 25 °C

Index of refraction: 1.4070

Hydrolyzes to butyric acid; wt/gal 8.1 lb at 20 °C

Molar heat capacity (298.15 K) = 283.7 J/mol K

Boiling point

Dielectric constant

Excess enthalpy

Heat of solution

Heat of sublimation

Mixing enthalpy

Optical coefficient

Refractive index

Vapor pressure

Viscosity

Other Classes -> Acid Anhydrides, Other

Corrosives

Flammable agents - 2nd degree

Reactive agents - 1st degree

Slowly reacts with water to form butyric acid.

Anhydrides

BUTYRIC ANHYDRIDE reacts exothermically with water. The reaction is usually slow, but might become violent if local heating accelerates their rate. Acids accelerate the reaction with water. Incompatible with acids, strong oxidizing agents, alcohols, amines, and bases.

Dermatotoxin - Skin burns.

Toxic Pneumonitis - Inflammation of the lungs induced by inhalation of metal fumes or toxic gases and vapors.

LC (rat) > 50 mg/m3

LD50 Rat oral 8790 mg/kg

Whole unfractionated heparin can modestly decrease tumor growth, but the dose of heparin is limited by its anticoagulant properties. To overcome this limitation... the chemical structure of heparin /was modified/ and a heparin derivative /was prepared/ by O-acylating low molecular weight heparin with butyric anhydride, producing a more potent antiproliferative compound, which is only weakly anticoagulant so that the dose may be escalated without threat of hemorrhage. ...this study... investigated the effect of this chemically modified heparin, butanoylated heparin, on the growth of lung cancer in vitro and in vivo. /It was/ found that butanoylated heparin a) significantly inhibited lung cancer cell proliferation in vitro and lung cancer growth in mice and rats; b) had very low anticoagulant effect; c) had no significant toxicity on heart, liver, kidney and lung; d) significantly although modestly induced apoptosis and decreased expression of the cell proliferation pathway consisting of mutant p53, phospho-Rb and E2F1 expression in the tumor tissues. /It was/ also found that butanoylated heparin significantly inhibited CXCL12 and CXCR4 expression, suggesting that CXCL12/CXCR4 axis may be involved in regulation of tumor growth inhibition by heparin. /It was/ concluded that chemically modified butanoylated heparin has potent antiproliferative activity against lung cancer and may represent a new chemical therapeutic agent for cancer patients.

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 as necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on 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. /Organic acids 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 respirations if necessary. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . Monitor for shock 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. Activated charcoal is not effective ... . Do not attempt to neutralize because of exothermic reaction. Cover skin burns with dry, sterile dressings after decontamination ... . /Organic acids 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. Early intubation, at the first sign of upper airway obstruction, may be necessary. Positive-pressure ventilation techniques with a bag valve mask device may be beneficial. Consider drug therapy for pulmonary edema ... . Consider administering a beta agonist such as albuterol for severe bronchospasm ... . 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. Consider vasopressors if patient is hypotensive with a normal fluid volume. Watch for signs of fluid overload ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Organic acids and related compounds/

/SIGNS AND SYMPTOMS/ BUTYRIC ANHYDRIDE CAUSES PERSISTENT EYE IRRITATION IF CONTACT WITH VAPOR IS REPEATED AND PROLONGED. IT IS ALSO A SKIN IRRITANT.

/SIGNS AND SYMPTOMS/ ...THEY MAY PRODUCE CHRONIC CONJUNCTIVITIS. THEY ARE SLOWLY HYDROLYZED ON CONTACT WITH BODY TISSUES AND MAY OCCASIONALLY CAUSE SENSITIZATION. /ACID ANHYDRIDES/

Butyric anhydride's production and use in the manufacture of butyrates, drugs, and tanning agents may result in its release to the environment through various waste streams. If released to air, a vapor pressure of 0.3 mm Hg at 25 °C indicates butyric anhydride will exist solely as a vapor in the atmosphere. Vapor-phase butyric anhydride 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 4.8 days. If released to soil, butyric anhydride is expected to have very high mobility based upon an estimated Koc of 10. Due to hydrolysis, volatilization and leaching in wet soils are not expected to be important fate processes. Volatilization from dry surfaces is possible based upon the vapor pressure and butyric anhydride's existence as a liquid at ambient temperatures. If released to water, hydrolysis will be dominant fate process. Based on analogy to similar anhydrides, the neutral hydrolysis half-life of butyric anhydride at 25 °C is about 4.3 minutes. An estimated base-catalyzed second-order hydrolysis rate constant of 3440 L/mole-sec corresponds to half-lives of 17 and 1.7 minutes at pH values of 7 and 8, respectively. Occupational exposure to butyric anhydride may occur through inhalation of vapor and dermal contact with this compound at workplaces where butyric anhydride is produced or used. (SRC)

Butyric anhydride's production and use in the manufacture of butyrates, drugs, and tanning agents(1) may result in its release to the environment through various waste streams(SRC).

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 10(SRC), determined from a structure estimation method(2), indicates that butyric anhydride is expected to have very high mobility in soil(SRC). However, butyric anhydride hydrolyzes to butyric acid in water(3); the neutral hydrolysis half-life at 25 °C is about 4.3 minutes based on analogy to similar anhydrides(2). Therefore leaching in soil due to rain or runoff is not expected to be an important fate process. The potential for volatilization of butyric anhydride from dry soil surfaces may exist(SRC) based upon a vapor pressure of 0.3 mm Hg at 25 °C(4) and its existence as a liquid at ambient temperatures(3).

AQUATIC FATE: Hydrolysis is the dominant fate process for butyric anhydride in water(SRC). In water, butyric anhydride hydrolyzes to butyric acid(1). Based on analogy to similar anhydrides(SRC), the neutral aqueous hydrolysis half-life of butyric anhydride at 25 °C is about 4.3 minutes(2). A base-catalyzed second-order hydrolysis rate constant of 3440 L/mole-sec(SRC) was estimated using a structure estimation method(3); this corresponds to half-lives of 17 and 1.7 minutes at pH values of 7 and 8, respectively(SRC). Due to hydrolysis, bioconcentration and volatilization are not expected to be important fate processes(SRC).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), butyric anhydride, which has a vapor pressure of 0.3 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase butyric anhydride 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 4.8 days(SRC), calculated from its rate constant of 3.34X10-12 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3).

The rate constant for the vapor-phase reaction of butyric anhydride with photochemically-produced hydroxyl radicals has been estimated as 3.34X10-12 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 4.8 days at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). Based on analogy to similar anhydrides(SRC), the neutral aqueous hydrolysis half-life of butyric anhydride at 25 °C is about 4.3 minutes(1). A base-catalyzed second-order hydrolysis rate constant of 3440 L/mole-sec(SRC) was estimated using a structure estimation method(2); this corresponds to half-lives of 17 and 1.7 minutes at pH values of 7 and 8, respectively(SRC).

Butyric anhydride hydrolyzes to butyric acid in water(1); the neutral hydrolysis half-life at 25 °C is about 4.3 minutes based on analogy to similar anhydrides(2). Therefore, butyric anhydride is not expected to bioconcentrate in fish(SRC).

Using a structure estimation method based on molecular connectivity indices(1), the Koc of butyric anhydride can be estimated to be 10(SRC). According to a classification scheme(2), this estimated Koc value suggests that butyric anhydride is expected to have very high mobility in soil. However, butyric anhydride hydrolyzes to butyric acid in water(2); the neutral hydrolysis half-life at 25 °C is about 4.3 minutes based on analogy to similar anhydrides(1).

Butyric anhydride hydrolyzes to butyric acid in water(1); the neutral hydrolysis half-life at 25 °C is about 4.3 minutes based on analogy to similar anhydrides(2). Therefore, volatilization of butyric anhydride from surface waters or moist soil is not expected to be an important fate process(SRC). The potential for volatilization of butyric anhydride from dry soil surfaces may exist(SRC) based upon a vapor pressure of 0.3 mm Hg at 25 °C(3) and its existence as a liquid at ambient temperatures(1).

According to the 2006 TSCA Inventory Update Reporting data, the number of persons reasonably likely to be exposed in the industrial manufacturing, processing, and use of butyric anhydride is 1000 or greater; the data may be greatly underestimated(1).

NIOSH (NOES Survey 1981-1983) has statistically estimated that 4,817 workers (755 of these were female) were potentially exposed to butyric anhydride in the US(1). Occupational exposure to butyric anhydride may occur through inhalation of vapor and dermal contact with this compound at workplaces where butyric anhydride is produced or used(SRC).

Butyric anhydride's production and use in the manufacture of butyrates, drugs, and tanning agents may result in its release to the environment through various waste streams. If released to air, a vapor pressure of 0.3 mm Hg at 25 °C indicates butyric anhydride will exist solely as a vapor in the atmosphere. Vapor-phase butyric anhydride 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 4.8 days. If released to soil, butyric anhydride is expected to have very high mobility based upon an estimated Koc of 10. Due to hydrolysis, volatilization and leaching in wet soils are not expected to be important fate processes. Volatilization from dry surfaces is possible based upon the vapor pressure and butyric anhydride's existence as a liquid at ambient temperatures. If released to water, hydrolysis will be dominant fate process. Based on analogy to similar anhydrides, the neutral hydrolysis half-life of butyric anhydride at 25 °C is about 4.3 minutes. An estimated base-catalyzed second-order hydrolysis rate constant of 3440 L/mole-sec corresponds to half-lives of 17 and 1.7 minutes at pH values of 7 and 8, respectively. Occupational exposure to butyric anhydride may occur through inhalation of vapor and dermal contact with this compound at workplaces where butyric anhydride is produced or used. (SRC)

Butyric anhydride's production and use in the manufacture of butyrates, drugs, and tanning agents(1) may result in its release to the environment through various waste streams(SRC).

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 10(SRC), determined from a structure estimation method(2), indicates that butyric anhydride is expected to have very high mobility in soil(SRC). However, butyric anhydride hydrolyzes to butyric acid in water(3); the neutral hydrolysis half-life at 25 °C is about 4.3 minutes based on analogy to similar anhydrides(2). Therefore leaching in soil due to rain or runoff is not expected to be an important fate process. The potential for volatilization of butyric anhydride from dry soil surfaces may exist(SRC) based upon a vapor pressure of 0.3 mm Hg at 25 °C(4) and its existence as a liquid at ambient temperatures(3).

AQUATIC FATE: Hydrolysis is the dominant fate process for butyric anhydride in water(SRC). In water, butyric anhydride hydrolyzes to butyric acid(1). Based on analogy to similar anhydrides(SRC), the neutral aqueous hydrolysis half-life of butyric anhydride at 25 °C is about 4.3 minutes(2). A base-catalyzed second-order hydrolysis rate constant of 3440 L/mole-sec(SRC) was estimated using a structure estimation method(3); this corresponds to half-lives of 17 and 1.7 minutes at pH values of 7 and 8, respectively(SRC). Due to hydrolysis, bioconcentration and volatilization are not expected to be important fate processes(SRC).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), butyric anhydride, which has a vapor pressure of 0.3 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase butyric anhydride 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 4.8 days(SRC), calculated from its rate constant of 3.34X10-12 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3).

The rate constant for the vapor-phase reaction of butyric anhydride with photochemically-produced hydroxyl radicals has been estimated as 3.34X10-12 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 4.8 days at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). Based on analogy to similar anhydrides(SRC), the neutral aqueous hydrolysis half-life of butyric anhydride at 25 °C is about 4.3 minutes(1). A base-catalyzed second-order hydrolysis rate constant of 3440 L/mole-sec(SRC) was estimated using a structure estimation method(2); this corresponds to half-lives of 17 and 1.7 minutes at pH values of 7 and 8, respectively(SRC).

Butyric anhydride hydrolyzes to butyric acid in water(1); the neutral hydrolysis half-life at 25 °C is about 4.3 minutes based on analogy to similar anhydrides(2). Therefore, butyric anhydride is not expected to bioconcentrate in fish(SRC).

Using a structure estimation method based on molecular connectivity indices(1), the Koc of butyric anhydride can be estimated to be 10(SRC). According to a classification scheme(2), this estimated Koc value suggests that butyric anhydride is expected to have very high mobility in soil. However, butyric anhydride hydrolyzes to butyric acid in water(2); the neutral hydrolysis half-life at 25 °C is about 4.3 minutes based on analogy to similar anhydrides(1).

Butyric anhydride hydrolyzes to butyric acid in water(1); the neutral hydrolysis half-life at 25 °C is about 4.3 minutes based on analogy to similar anhydrides(2). Therefore, volatilization of butyric anhydride from surface waters or moist soil is not expected to be an important fate process(SRC). The potential for volatilization of butyric anhydride from dry soil surfaces may exist(SRC) based upon a vapor pressure of 0.3 mm Hg at 25 °C(3) and its existence as a liquid at ambient temperatures(1).

According to the 2006 TSCA Inventory Update Reporting data, the number of persons reasonably likely to be exposed in the industrial manufacturing, processing, and use of butyric anhydride is 1000 or greater; the data may be greatly underestimated(1).

NIOSH (NOES Survey 1981-1983) has statistically estimated that 4,817 workers (755 of these were female) were potentially exposed to butyric anhydride in the US(1). Occupational exposure to butyric anhydride may occur through inhalation of vapor and dermal contact with this compound at workplaces where butyric anhydride is produced or used(SRC).

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination. 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 soil or water; effects on animal and plant life; and conformance with environmental and public health regulations.

/GUIDE 156: SUBSTANCES - TOXIC and/or CORROSIVE (Combustible/Water-Sensitive)/ Fire or Explosion: Combustible material: may burn but does not ignite readily. Substance will react with water (some violently) releasing flammable, toxic or corrosive gases and runoff. When heated, vapors may form explosive mixtures with air: indoors, outdoors and sewers explosion hazards. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapors may travel to source of ignition and flash back. Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated or if contaminated with water.

/GUIDE 156: SUBSTANCES - TOXIC and/or CORROSIVE (Combustible/Water-Sensitive)/ Health: TOXIC; inhalation, ingestion or contact (skin, eyes) with vapors, dusts or substance may cause severe injury, burns or death. Contact with molten substance may cause severe burns to skin and eyes. Reaction with water or moist air will release toxic, corrosive or flammable gases. Reaction with water may generate much heat that will increase the concentration of fumes in the air. Fire will produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may be corrosive and/or toxic and cause pollution.

/GUIDE 156: SUBSTANCES - TOXIC and/or CORROSIVE (Combustible/Water-Sensitive)/ 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 in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids. Keep unauthorized personnel away. Stay upwind. Keep out of low areas. Ventilate enclosed areas.

/GUIDE 156: SUBSTANCES - TOXIC and/or CORROSIVE (Combustible/Water-Sensitive)/ Protective Clothing: Wear positive pressure self-contained breathing apparatus (SCBA). Wear chemical protective clothing that is specifically recommended by the manufacturer. It may provide little or no thermal protection. Structural firefighters' protective clothing provides limited protection in fire situations ONLY; it is not effective in spill situations where direct contact with the substance is possible.

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

UN 2739; Butyric anhydride

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.

Corrosive