Methyl Lactate

H226: Flammable liquid and vapor [Warning Flammable liquids]

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

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

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

H226 (100%): Flammable liquid and vapor [Warning Flammable liquids]

H319 (100%): Causes serious eye irritation [Warning Serious eye damage/eye irritation]

H335 (100%): May cause respiratory irritation [Warning Specific target organ toxicity, single exposure; Respiratory tract irritation]

Aggregated GHS information provided per 1640 reports by companies from 13 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

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

Aggregated GHS information provided per 235 reports by companies from 3 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

P210, P233, P240, P241, P242, P243, P280, P303+P361+P353, P370+P378, P403+P235, and P501 (click each P-code to see the statement)

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

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

Use water spray to cool unopened containers.

For small fires, use dry chemical, carbon dioxide, water spray or alcohol-resistant foam. For large fires, use water spray, fog, or alcohol-resistant foam. Use water spray to cool fire-exposed containers. Water may be ineffective. Do NOT get water inside containers. Do NOT use straight streams of water.

Vapors may form an explosive mixture with air. Vapors can travel to a source of ignition and flash back. During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion. Will burn if involved in a fire. ... Containers may explode in the heat of a fire. Flammable liquid and vapor. Vapors may be heavier than air. They can spread along the ground and collect in low or confined areas.

ACCIDENTAL RELEASE MEASURES: Personal precautions, protective equipment and emergency procedures: Use personal protective equipment. 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; 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: 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.

Precautions for safe handling: Avoid contact with skin and eyes. Avoid inhalation of vapor or mist. 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.

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. Moisture sensitive.

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: Impervious clothing. 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 ABEK (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).

Colorless liquid; [Hawley]

Colorless, transparent liquid

144-145 °C

Freezing Point: approximately -66 °C

51 °C (124 °F) - closed cup

121 °F (49 °C) (closed cup)

Miscible in water with decomposition

Soluble in alcohol, ether

Miscible with most organic solvents

1.09 at 19 °C

/Bulk density/ (wt/gal)= 9 LB @ 68 °F

3.6 (Air = 1)

1.85 [mmHg]

3.5 mm Hg at 25 °C

Stable under recommended storage conditions.

725 °F (385 °C)

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

2.94 cP at 20 °C

Enthalpy of vaporization: 44.7 kJ/mol (313-418 deg K)

Index of refraction: 1.4156 at 16 °C/D

Wt/vol conversion: 4.25 mg/cu m is equivalent to 1 ppm

Oil. BP: 144.8 °C. Density: 1.0928 g/cu cm at 20 °C. Index of refraction: 1.4141 at 20 °C/D. Very soluble in water, ethyl ether, ethanol/(+/-)-Methyl lactate/

Soluble in water, alcohol, ether; Specific optical rotation: +7.46 deg at 20 °C/D; BP: 40 °C at 13 mm Hg; Density 1.0857 at 25 °C/4 °C /Methyl d-lactate/

Soluble in water, alcohol, ether; Specific optical rotation: -8.3 deg at 20 °C/D; BP 58 °C at 19 mm Hg; Density 1.0895 at 20 °C/4 °C; Index of refraction: 1.4139 at 20 °C/D /Methyl L-lactate/

Henry's Law constant = 4.8X10-7 atm-cu m/mol at 25 °C /estimated from vapor pressure and water solubility/

Hydroxyl radical reaction rate constant = 2.80X10-12 cu cm/molecule-sec at 25 °C

Cosmetic ingredients (Methyl Lactate) -> CIR (Cosmetic Ingredient Review)

Solvents -> Esters (<C12)

Incompatible materials: Oxidizing agents, acids, Bases

Based on the available information included in this report, the CIR Expert Panel concludes that Glycolic and Lactic Acid, their common salts and their simple esters, are safe for use in cosmetic products at concentrations less than or equal to 10%, at final formulation pH greater than or equal to 3.5, when formulated to avoid increasing sun sensitivity or when directions for use include the daily use of sun protection. These ingredients are safe for use in salon products at concentrations less than or equal to 30%, at final formulation pH greater than or equal to 3.0, in products designed for brief, discontinuous use followed by thorough rinsing from the skin, when applied by trained professionals, and when application is accompanied by directions for the daily use of sun protection...Methyl Lactate...

Safe for use in cosmetics, with qualifications

IDENTIFICATION AND USE: Methyl lactate is a colorless, transparent liquid. It is used as a solvent. HUMAN EXPOSURE AND TOXICITY: There is no data. ANIMAL STUDIES: Methyl Lactate was not irritating to guinea pig and rabbit eyes. The estimated average lethal dose for the female rat following ip injection of laboratory grade methyl lactate was >2000 mg/kg. Observations included narcosis, respiratory distress, and peritoneal adhesions. Hydrolysis of lactate esters to lactic acid and alcohol has been reported to occur after both skin application and oral administration. Lactic acid is a naturally occurring metabolite, and its toxicity is mostly a result of its acidity.

Neurotoxin - Acute solvent syndrome

LC50 (rat) > 5,000 mg/m3/4h

/SRP:/ 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. /Poisons A and B/

/SRP:/ 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 needed. 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 ... . 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 ... . Cover skin burns with dry sterile dressings after decontamination ... . /Poisons A and B/

/SRP:/ 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 ... . Consider administering a beta agonist such as albuterol for severe bronchospasm ... . Monitor cardiac rhythm and treat arrhythmias as necessary ... . Start IV administration of D5W TKO /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 or lorazepam ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Poisons A and B/

/LABORATORY ANIMALS: Acute Exposure/ Methyl Lactate was not irritating to guinea pig eyes.

/LABORATORY ANIMALS: Acute Exposure/ Methyl Lactate. The estimated average lethal dose for the female rat (either albino, Wistar, or Glaxo-Wistar) following IP injection of laboratory grade Methyl Lactate was >2000 mg/kg. Observations included /CNS depression/, respiratory distress, and peritoneal adhesions. The estimated maximum nontoxic dose and estimated maximum dose without gross lesions at necropsy was 500 mg/kg.

/LABORATORY ANIMALS: Acute Exposure/ Lactate esters dropped into the eyes of rabbits caused eye irritation. Tested esters that yielded a positive response were ethyl, n-propyl, n-butyl, lauryl, and myristyl lactate. Methyl lactate, however, was classified as non-irritating.

EPA has released the Interactive Chemical Safety for Sustainability (iCSS) Dashboard. The iCSS Dashboard provides an interactive tool to explore rapid, automated (or in vitro high-throughput) chemical screening data generated by the Toxicity Forecaster (ToxCast) project and the federal Toxicity Testing in the 21st century (Tox21) collaboration. /The title compound was tested by ToxCast and/or Tox21 assays/[USEPA; ICSS Dashboard Application; Available from, as of December 17, 2015: http://actor.epa.gov/dashboard/]

EC50; Species: Daphnia magna (Water flea); Conditions: freshwater, static; Concentration: 780000 ug/L for 48 hr (95% confidence interval: 689000-882000 ug/L); Effect: intoxication, decreased mobility /97% purity/

Methyl lactate's production and use as a solvent for cellulose acetate, nitrocellulose, cellulose acetobutyrate, cellulose acetopropionate, lacquers and stains as well as an ingredient in some cosmetics may result in its release to the environment through various waste streams. If released to air, a vapor pressure of 3.5 mm Hg at 25 °C indicates methyl lactate will exist solely as a vapor in the atmosphere. Vapor-phase methyl lactate 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 6 days. Methyl lactate does not contain chromophores that absorb at wavelengths >290 nm and, therefore, is not expected to be susceptible to direct photolysis by sunlight. If released to soil, methyl lactate is expected to have very high mobility based upon an estimated Koc of 1. Volatilization from moist soil surfaces is not expected to be an important fate process based upon an estimated Henry's Law constant of 4.8X10-7 atm-cu m/mole. Methyl lactate is expected to volatilize from dry soil surfaces based upon its vapor pressure. Utilizing the OECD 301D closed-bottle test, 76% of the Theoretical BOD was reached in 28 days indicating that biodegradation is an important environmental fate process in soil and water. Hydrolysis may be an important fate process in moist alkaline soils and water. If released into water, methyl lactate is not expected to adsorb to suspended solids and sediment based upon the estimated Koc. Methyl lactate and the lactate ester compounds are considered to be readily biodegradable. Volatilization from water surfaces is not expected to be an important fate process based upon this compound's estimated Henry's Law constant. An estimated BCF of 3 suggests the potential for bioconcentration in aquatic organisms is low. The base-catalyzed hydrolysis half-lives are estimated to be 68, 6.8 and 0.68 days at pH values of 7, 8 and 9, respectively. Occupational exposure to methyl lactate may occur through inhalation and dermal contact with this compound at workplaces where methyl lactate is produced or used. Use data indicate that the general population may be exposed to methyl lactate via inhalation and dermal contact with consumer products containing methyl lactate. (SRC)

Methyl lactate's production and use as a solvent for cellulose acetate, nitrocellulose, cellulose acetobutyrate, cellulose acetopropionate, lacquers and stains(1) as well as an ingredient in some cosmetics(2) and development as a possible "green" solvent(3) 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 1(SRC), determined from a structure estimation method(2), indicates that methyl lactate is expected to have very high mobility in soil(SRC). Volatilization of methyl lactate from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 4.8X10-7 atm-cu m/mole(SRC), derived from its vapor pressure, 3.5 mm Hg(3), and an assigned value for water solubility of 1.0X10+6 mg/L (miscible)(4). Methyl lactate is expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(3). A 76% of theoretical BOD using activated sludge in a 28-day OECD 301D closed-bottle test indicates methyl lactate is readily biodegradable(5) and suggests that biodegradation is an important environmental fate process in soil(SRC). The lactate ester group of compounds are generally considered to be readily biodegradable(5,6). Hydrolysis may be an important fate process in moist alkaline soils(SRC). A base-catalyzed second-order hydrolysis rate constant of 1.18 L/mole-sec(SRC) was estimated using a structure estimation method for 25 °C(2); this corresponds to half-lives of 68, 6.8 and 0.68 days at pH values of 7, 8 and 9, respectively(SRC).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 1(SRC), determined from a structure estimation method(2), indicates that methyl lactate is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is not expected(3) based upon an estimated Henry's Law constant of 4.8X10-7 atm-cu m/mole(SRC), derived from its vapor pressure, 3.5 mm Hg(4), and an assigned value for water solubility of 1.0X10+6 mg/L (miscible)(5). According to a classification scheme(6), an estimated BCF of 3(SRC), from an estimated log Kow of -0.67(2) and a regression-derived equation(2), suggests the potential for bioconcentration in aquatic organisms is low(SRC). A 76% of theoretical BOD using activated sludge in a 28-day OECD 301D closed-bottle test indicates methyl lactate acid is readily biodegradable(7) and suggests that biodegradation is an important environmental fate process in water(SRC). The lactate ester group of compounds are generally considered to be readily biodegradable(7,8). Hydrolysis may be an important fate process in alkaline waters(SRC). A base-catalyzed second-order hydrolysis rate constant of 1.18 L/mole-sec(SRC) was estimated using a structure estimation method for 25 °C(2); this corresponds to half-lives of 68, 6.8 and 0.68 days at pH values of 7, 8 and 9, respectively(SRC).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), methyl lactate, which has a vapor pressure of 3.5 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase methyl lactate 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 6 days(SRC), calculated from its rate constant of 2.8X10-12 cu cm/molecule-sec at 25 °C(3). Methyl lactate does not contain chromophores that absorb at wavelengths >290 nm(4) and, therefore, is not expected to be susceptible to direct photolysis by sunlight(SRC).

AEROBIC: Methyl lactate, present at 2.04 mg/L, reached 76% of its theoretical BOD in 28 days using an activated sludge inoculum in the OECD 301D Method (Closed Bottle Test) which classified the compound as readily biodegradable(1). The similar compound ethyl lactate was found to be readily biodegradable using the Japanese MITI test(2). The lactate ester group of compounds are generally considered to be readily biodegradable(1,3).

The rate constant for the vapor-phase reaction of methyl lactate with photochemically-produced hydroxyl radicals has been measured as 2.8X10-12 cu cm/molecule-sec at 25 °C(1). This corresponds to an atmospheric half-life of about 6 days at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(2). Methyl lactate is reported to be miscible in water with decomposition(3). A base-catalyzed second-order hydrolysis rate constant of 1.18 L/mole-sec(SRC) was estimated using a structure estimation method for 25 °C(2); this corresponds to half-lives of 68 and 6.8 days at pH values of 7 and 8, respectively(2). Methyl lactate does not contain chromophores that absorb at wavelengths >290 nm(4) and, therefore, is not expected to be susceptible to direct photolysis by sunlight(SRC).

An estimated BCF of 3 was calculated in fish for methyl lactate(SRC), using an estimated log Kow of -0.67(1) and a regression-derived equation(1). According to a classification scheme(2), this BCF suggests the potential for bioconcentration in aquatic organisms is low(SRC).

Using a structure estimation method based on molecular connectivity indices(1), the Koc of methyl lactate can be estimated to be 1(SRC). According to a classification scheme(2), this estimated Koc value suggests that methyl lactate is expected to have very high mobility in soil.

The Henry's Law constant for methyl lactate is estimated as 4.8X10-7 atm-cu m/mole(SRC) derived from its vapor pressure, 3.5 mm Hg(1), and an assigned value for water solubility of 1.00X10+6 mg/L (miscible)(2). This Henry's Law constant indicates that methyl lactate is expected to be essentially nonvolatile from water surfaces(3). Methyl lactate's estimated Henry's Law constant indicates that volatilization from moist soil surfaces is not expected to occur(SRC). Methyl lactate is expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(1).

Occupational exposure to methyl lactate may occur through inhalation and dermal contact with this compound at workplaces where methyl lactate is produced or used. Use data indicate that the general population may be exposed to methyl lactate via inhalation and dermal contact with consumer products containing methyl lactate. (SRC)

EC50; Species: Daphnia magna (Water flea); Conditions: freshwater, static; Concentration: 780000 ug/L for 48 hr (95% confidence interval: 689000-882000 ug/L); Effect: intoxication, decreased mobility /97% purity/

Methyl lactate's production and use as a solvent for cellulose acetate, nitrocellulose, cellulose acetobutyrate, cellulose acetopropionate, lacquers and stains as well as an ingredient in some cosmetics may result in its release to the environment through various waste streams. If released to air, a vapor pressure of 3.5 mm Hg at 25 °C indicates methyl lactate will exist solely as a vapor in the atmosphere. Vapor-phase methyl lactate 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 6 days. Methyl lactate does not contain chromophores that absorb at wavelengths >290 nm and, therefore, is not expected to be susceptible to direct photolysis by sunlight. If released to soil, methyl lactate is expected to have very high mobility based upon an estimated Koc of 1. Volatilization from moist soil surfaces is not expected to be an important fate process based upon an estimated Henry's Law constant of 4.8X10-7 atm-cu m/mole. Methyl lactate is expected to volatilize from dry soil surfaces based upon its vapor pressure. Utilizing the OECD 301D closed-bottle test, 76% of the Theoretical BOD was reached in 28 days indicating that biodegradation is an important environmental fate process in soil and water. Hydrolysis may be an important fate process in moist alkaline soils and water. If released into water, methyl lactate is not expected to adsorb to suspended solids and sediment based upon the estimated Koc. Methyl lactate and the lactate ester compounds are considered to be readily biodegradable. Volatilization from water surfaces is not expected to be an important fate process based upon this compound's estimated Henry's Law constant. An estimated BCF of 3 suggests the potential for bioconcentration in aquatic organisms is low. The base-catalyzed hydrolysis half-lives are estimated to be 68, 6.8 and 0.68 days at pH values of 7, 8 and 9, respectively. Occupational exposure to methyl lactate may occur through inhalation and dermal contact with this compound at workplaces where methyl lactate is produced or used. Use data indicate that the general population may be exposed to methyl lactate via inhalation and dermal contact with consumer products containing methyl lactate. (SRC)

Methyl lactate's production and use as a solvent for cellulose acetate, nitrocellulose, cellulose acetobutyrate, cellulose acetopropionate, lacquers and stains(1) as well as an ingredient in some cosmetics(2) and development as a possible "green" solvent(3) 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 1(SRC), determined from a structure estimation method(2), indicates that methyl lactate is expected to have very high mobility in soil(SRC). Volatilization of methyl lactate from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 4.8X10-7 atm-cu m/mole(SRC), derived from its vapor pressure, 3.5 mm Hg(3), and an assigned value for water solubility of 1.0X10+6 mg/L (miscible)(4). Methyl lactate is expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(3). A 76% of theoretical BOD using activated sludge in a 28-day OECD 301D closed-bottle test indicates methyl lactate is readily biodegradable(5) and suggests that biodegradation is an important environmental fate process in soil(SRC). The lactate ester group of compounds are generally considered to be readily biodegradable(5,6). Hydrolysis may be an important fate process in moist alkaline soils(SRC). A base-catalyzed second-order hydrolysis rate constant of 1.18 L/mole-sec(SRC) was estimated using a structure estimation method for 25 °C(2); this corresponds to half-lives of 68, 6.8 and 0.68 days at pH values of 7, 8 and 9, respectively(SRC).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 1(SRC), determined from a structure estimation method(2), indicates that methyl lactate is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is not expected(3) based upon an estimated Henry's Law constant of 4.8X10-7 atm-cu m/mole(SRC), derived from its vapor pressure, 3.5 mm Hg(4), and an assigned value for water solubility of 1.0X10+6 mg/L (miscible)(5). According to a classification scheme(6), an estimated BCF of 3(SRC), from an estimated log Kow of -0.67(2) and a regression-derived equation(2), suggests the potential for bioconcentration in aquatic organisms is low(SRC). A 76% of theoretical BOD using activated sludge in a 28-day OECD 301D closed-bottle test indicates methyl lactate acid is readily biodegradable(7) and suggests that biodegradation is an important environmental fate process in water(SRC). The lactate ester group of compounds are generally considered to be readily biodegradable(7,8). Hydrolysis may be an important fate process in alkaline waters(SRC). A base-catalyzed second-order hydrolysis rate constant of 1.18 L/mole-sec(SRC) was estimated using a structure estimation method for 25 °C(2); this corresponds to half-lives of 68, 6.8 and 0.68 days at pH values of 7, 8 and 9, respectively(SRC).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), methyl lactate, which has a vapor pressure of 3.5 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase methyl lactate 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 6 days(SRC), calculated from its rate constant of 2.8X10-12 cu cm/molecule-sec at 25 °C(3). Methyl lactate does not contain chromophores that absorb at wavelengths >290 nm(4) and, therefore, is not expected to be susceptible to direct photolysis by sunlight(SRC).

AEROBIC: Methyl lactate, present at 2.04 mg/L, reached 76% of its theoretical BOD in 28 days using an activated sludge inoculum in the OECD 301D Method (Closed Bottle Test) which classified the compound as readily biodegradable(1). The similar compound ethyl lactate was found to be readily biodegradable using the Japanese MITI test(2). The lactate ester group of compounds are generally considered to be readily biodegradable(1,3).

The rate constant for the vapor-phase reaction of methyl lactate with photochemically-produced hydroxyl radicals has been measured as 2.8X10-12 cu cm/molecule-sec at 25 °C(1). This corresponds to an atmospheric half-life of about 6 days at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(2). Methyl lactate is reported to be miscible in water with decomposition(3). A base-catalyzed second-order hydrolysis rate constant of 1.18 L/mole-sec(SRC) was estimated using a structure estimation method for 25 °C(2); this corresponds to half-lives of 68 and 6.8 days at pH values of 7 and 8, respectively(2). Methyl lactate does not contain chromophores that absorb at wavelengths >290 nm(4) and, therefore, is not expected to be susceptible to direct photolysis by sunlight(SRC).

An estimated BCF of 3 was calculated in fish for methyl lactate(SRC), using an estimated log Kow of -0.67(1) and a regression-derived equation(1). According to a classification scheme(2), this BCF suggests the potential for bioconcentration in aquatic organisms is low(SRC).

Using a structure estimation method based on molecular connectivity indices(1), the Koc of methyl lactate can be estimated to be 1(SRC). According to a classification scheme(2), this estimated Koc value suggests that methyl lactate is expected to have very high mobility in soil.

The Henry's Law constant for methyl lactate is estimated as 4.8X10-7 atm-cu m/mole(SRC) derived from its vapor pressure, 3.5 mm Hg(1), and an assigned value for water solubility of 1.00X10+6 mg/L (miscible)(2). This Henry's Law constant indicates that methyl lactate is expected to be essentially nonvolatile from water surfaces(3). Methyl lactate's estimated Henry's Law constant indicates that volatilization from moist soil surfaces is not expected to occur(SRC). Methyl lactate is expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(1).

Occupational exposure to methyl lactate may occur through inhalation and dermal contact with this compound at workplaces where methyl lactate is produced or used. Use data indicate that the general population may be exposed to methyl lactate via inhalation and dermal contact with consumer products containing methyl lactate. (SRC)

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.