Menthyl acetate

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.

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 5800(SRC), determined from an estimated log Kow of 4.39(2,SRC) and a regression-derived equation(3), indicates that menthyl acetate is expected to be immobile in soil(SRC). Volatilization of menthyl acetate from moist soil surfaces is expected to occur(SRC) given an estimated Henry's Law constant of 8.3X10-4 atm-cu m/mole(SRC), using a fragment constant estimation method(4). However, volatilization from moist soil surfaces is expected to be attenuated by adsorption to organic matter(SRC). In general, acetates are expected to be readily biodegradable(SRC).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 5800(SRC), determined from an estimated log Kow of 4.39(2,SRC) and a regression-derived equation(3), indicates that menthyl acetate is expected to adsorb to suspended solids and sediment in water(SRC). Menthyl acetate is expected to volatilize from water surfaces(3,SRC) based on an estimated Henry's Law constant of 8.3X10-4 atm-cu m/mole(SRC), developed using a fragment constant estimation method(4). Estimated volatilization half-lives for a model river and model lake are 5.6 hours and 6.0 days, respectively(3,SRC). However, adsorption to suspended solids and sediment in the water column is expected to attenuate this process(SRC). The volatilization half-life from a model pond 2 m deep is estimated to be about 2.7 days ignoring adsorption(5); when considering maximum adsorption, the volatilization half-life increases to 94 days(5). According to a classification scheme(6), an estimated BCF of 1300(3,SRC), from an estimated log Kow(2,SRC), suggests the potential for bioconcentration in aquatic organisms is very high(SRC). In general, acetates are expected to be readily biodegradable(SRC).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), menthyl acetate, which has a vapor pressure of 0.10 mm Hg at 25 °C(2,SRC), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase menthyl acetate 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 21 hours(3,SRC).

The Koc of menthyl acetate is estimated as approximately 5800(SRC), using an estimated log Kow of 4.39(1,SRC) and a regression-derived equation(2,SRC). According to a classification scheme(3), this estimated Koc value suggests that menthyl acetate is expected to be immobile in soil(SRC).

An estimated BCF of 1300 was calculated for menthyl acetate(SRC), using an estimated log Kow of 4.39(1,SRC) and a regression-derived equation(2). According to a classification scheme(3), this BCF suggests the potential for bioconcentration in aquatic organisms is very high(SRC).

The Henry's Law constant for menthyl acetate is estimated as 8.3X10-4 atm-cu m/mole(SRC) using a fragment constant estimation method(1). This Henry's Law constant indicates that menthyl acetate is expected to volatilize from water surfaces(2,SRC). Based on this Henry's Law constant, the estimated volatilization half-life from a model river (1 m deep, flowing 1 m/sec, wind velocity of 3 m/sec) is approximately 5.6 hours(2,SRC). The estimated volatilization half-life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec) is approximately 6.0 days(2,SRC). The volatilization half-life from a model pond 2 m deep is estimated to be about 2.7 days ignoring adsorption(3); when considering maximum adsorption, the volatilization half-life increases to 94 days(3). Menthyl acetate's Henry's Law constant(1,SRC) indicates that volatilization from moist soil surfaces may occur(SRC).

The rate constant for the vapor-phase reaction of menthyl acetate with photochemically-produced hydroxyl radicals has been estimated as 1.8X10-11 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1,SRC). This corresponds to an atmospheric half-life of about 21 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1,SRC). A base-catalyzed second-order hydrolysis rate constant of 3.0X10-2 L/mol-sec(SRC) was estimated using a structure estimation method(2); this corresponds to half-lives of 7.3 years and 270 days at pH values of 7 and 8, respectively(2,SRC).

Occupational exposure to menthyl acetate may occur through inhalation and dermal contact with this compound at workplaces where menthyl acetate is produced or used. The general population may be exposed to menthyl acetate via inhalation and dermal contact with consumer products, such as perfumes, containing menthyl acetate, and via ingestion of food. (SRC)

Menthyl acetate is present in peppermint oil. Menthyl acetate's production and use in perfumery may result in its release to the environment through various waste streams. If released to air, a vapor pressure of 0.10 mm Hg at 25 °C indicates menthyl acetate will exist solely as a vapor in the ambient atmosphere. Vapor-phase menthyl acetate 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 21 hours. If released to soil, menthyl acetate is expected to have no mobility based upon an estimated Koc of 5800. Volatilization from moist soil surfaces may occur based upon an estimated Henry's Law constant of 8.3X10-4 atm-cu m/mole. However, adsorption to organic matter is expected to attenuate this process. If released into water, menthyl acetate is expected to adsorb to suspended solids and sediment in water based on the estimated Koc. Volatilization from water surfaces may be an important fate process based on the estimated Henry's Law constant. Estimated volatilization half-lives for a model river and model lake are 5.6 hours and 6.0 days, respectively. However, adsorption to suspended solids and sediment in the water column is expected to attenuate this process. An estimated BCF of 1300 suggests the potential for bioconcentration in aquatic organisms is very high. Estimated hydrolysis half-lives of 270 days and 7.3 years at pH values of 8 and 7, respectively, suggest hydrolysis is not expected to be an important process. In general, acetates are expected to be readily biodegradable. Occupational exposure to menthyl acetate may occur through inhalation and dermal contact with this compound at workplaces where menthyl acetate is produced or used. The general population may be exposed to menthyl acetate via inhalation and dermal contact with consumer products, such as perfumes, containing this compound, and via ingestion of food. (SRC)

Menthyl acetate is a food additive permitted for direct addition to food for human consumption, as long as 1) the quantity added to food does not exceed the amount reasonably required to accomplish its intended physical, nutritive, or other technical effect in food, and 2) when intended for use in or on food it is of appropriate food grade and is prepared and handled as a food ingredient. Isobutyl acetate synthetic flavoring substances & adjuvants may be safely used in food in accordance with the following conditions ... They consist of one or more of the following /substances including isobutyl acetate/ used alone or in combination with flavoring substances generally recognized as safe in food, or regulated by an appropriate section in this part.