delta-Gluconolactone

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 10(SRC), determined from a structure estimation method(2), indicates that gluconolactone is expected to have very high mobility in soil(SRC). Volatilization from moist soil surfaces is not expected to be an important environmental fate process given an estimated Henry's law constant of 1.4X10-9 atm cu m/mol(SRC), derived from a structure estimation method(4). Gluconolactone is not expected to volatilize from dry soil surfaces given an estimated vapor pressure of 2.8X10-9 mm Hg(SRC), determined from a fragment constant method(5). A screening study indicates that gluconolactone may be susceptible to biodegradation under aerobic conditions(6), and under anaerobic conditions the yeast Saccharomyces bulderi rapidly ferments gluconolactone to ethanol and carbon dioxide(7), suggesting that biodegradation may occur in soil(SRC). Hydrolysis of gluconolactone to gluconic acid should occur rapidly in moist soils given a hydrolysis half-life of about 10 minutes at pH 6.6 and 60 minutes at pH 4(6).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 10(SRC), determined from a structure estimation method(2), indicates that gluconolactone is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is not expected to be an important environmental fate process(3), based upon an estimated Henry's law constant of 1.4X10-9 atm cu m/mol(SRC), derived from a structure estimation method(4). According to a classification scheme(5), an estimated BCF of 3(SRC), from an estimated log Kow of -1.98(6) and a regression-derived equation(7), suggests the potential for bioconcentration in aquatic organisms is low(SRC). Limited data suggest that biodegradation may occur in aquatic environments(8,9); however, hydrolysis is expected to be the dominant environmental fate process in water(SRC). Hydrolysis of gluconolactone to gluconic acid occurs rapidly, with a half-life of about 10 minutes at pH 6.6 and 60 minutes at pH 4(9).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), gluconolactone, which has an estimated vapor pressure of 2.8X10-9 mm Hg at 25 °C(2), is expected to exist solely in the particulate-phase in the ambient atmosphere. Particulate-phase gluconolactone is removed from the atmosphere by wet and dry deposition(SRC).

Additionally, the Panel concluded the available data are insufficient to make a determination that Glucarolactone is safe under the intended conditions of use in cosmetic formulations.

The available data are insufficient to support safety

Safe in the present practices of use and concentration. Ingredient, concentration, and use information are available in documents discoverable at https://cir-reports.cir-safety.org

Using a structure estimation method based on molecular connectivity indices(1), the Koc for gluconolactone can be estimated to be 10(SRC). According to a classification scheme(2), this estimated Koc value suggests that gluconolactone is expected to have very high mobility in soil(SRC).

Biological oxidation of glucose at the C1 position by dehydrogenases or oxidases yields gluconolactone(1). Incomplete oxidation of sugars in fruits and nectar by bacteria and fungi may lead to acidification and the accumulation of gluconolactone(1).

/HUMAN EXPOSURE STUDIES/ ...We have performed a double-blind clinical trial on 150 patients to evaluate the efficacy and skin tolerance of the alpha hydroxy acid gluconolactone 14% in solution (Nuvoderm lotion) in the treatment of mild to moderate acne when compared with its vehicle (placebo) and 5% benzoyl peroxide lotion. The results of this study showed that both gluconolactone and benzoyl peroxide had a significant effect in improving patients' acne by reducing the number of lesions (inflamed and non-inflamed). Furthermore, fewer side-effects were experienced by patients treated with gluconolactone when compared with benzoyl peroxide

Gluconolactone's production and use in cleaning compounds, dairy industry to prevent milkstone, in breweries to prevent beerstone, as a coagulant for tofu and as a latent acid catalyst(1), may result in its release to the environment through various waste streams(SRC). Gluconolactone is allowed for use in human food as a curing and pickling agent, a leavening agent, a pH control agent, and a sequestrant(2), and in some cosmetics to act as a sunscreen(3).

AEROBIC: The 5-day theoretical BOD of gluconolactone was reported as 52%(1).

ANAEROBIC: Under anaerobic conditions, the yeast Saccharomyces bulderi rapidly ferments gluconolactone to ethanol and carbon dioxide(1).

An estimated BCF of 3 was calculated for gluconolactone(SRC), using an estimated log Kow of -1.98(1) and a regression-derived equation(2). According to a classification scheme(3), this BCF suggests the potential for bioconcentration in aquatic organisms is low(SRC).

The Henry's Law constant for gluconolactone is estimated as 1.4X10-9 atm cu m/mol(SRC) using a fragment constant estimation method(1). This Henry's Law constant indicates that gluconolactone is expected to be essentially nonvolatile from water and moist soil surfaces(2). Gluconolactone is not expected to volatilize from dry soil surfaces based upon an estimated vapor pressure of 2.8X10-9 mm Hg(SRC) determined from a fragment constant method(3).

The rate constant for the vapor-phase reaction of gluconolactone with photochemically-produced hydroxyl radicals has been estimated as 3.2X10-11 cu cm/molecule-sec(SRC), using a structure estimation method(1). This corresponds to an atmospheric half-life of about 12 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). Gluconolactone absorbs light greater than 290 nm and may be susceptible to direct photolysis(2); however the rate of this potential reaction is not known. Gluconolactone hydrolyzes to gluconic acid with a half-life of about 10 minutes at pH 6.6 and 60 minutes at pH 4(3).

NIOSH (NOES Survey 1981-1983) has statistically estimated that 184,229 workers (157,249 of these are female) are potentially exposed to gluconolactone in the US(1). Occupational exposure to gluconolactone may occur through inhalation and dermal contact with this compound at workplaces where gluconolactone is produced or used(SRC). The general population may be exposed to this compound by ingestion of foods containing gluconolactone and dermal contact with cosmetic products that use this compound as a sunscreen(SRC).

Gluconolactone's production and use in cleaning compounds, the dairy industry, breweries, and as a latent acid catalyst, may result in its release to the environment through various waste streams. Gluconolactone is also used as a food additive and in some cosmetics as a sunscreen. The biological oxidation of glucose also leads to the formation of gluconolactone. If released to air, an estimated vapor pressure of 2.8X10-9 mm Hg at 25 °C indicates gluconolactone will exist solely in the particulate-phase. Particulate-phase gluconolactone is removed from the atmosphere by wet and dry deposition. If released to soil, gluconolactone is expected to have very high mobility based upon an estimated Koc of 10. Volatilization from moist soil surfaces is not expected to be an important fate process given an estimated Henry's Law constant of 1.4X10-9 atm-cu m/mole. Gluconolactone is not expected to volatilize from dry soil surfaces based upon its estimated vapor pressure. A screening study indicates that gluconolactone may be susceptible to biodegradation under aerobic conditions, and under anaerobic conditions the yeast Saccharomyces bulderi rapidly ferments gluconolactone to ethanol and carbon dioxide. If released into water, gluconolactone is not expected to adsorb to suspended solids and sediment based upon the estimated Koc. Volatilization from water surfaces is not expected to be an important fate process based upon this compound's estimated Henry's Law constant. Hydrolysis is expected to be the dominant environmental fate process for gluconolactone in water. The hydrolysis half-lives of gluconolactone at pH 6.6 and 4 are 10 minutes and 60 minutes, respectively. An estimated BCF of 3 suggests the potential for bioconcentration in aquatic organisms is low. Occupational exposure to gluconolactone may occur through inhalation and dermal contact with this compound at workplaces where it is produced or used. The general population may be exposed to this compound by ingestion of foods containing gluconolactone and dermal contact with cosmetic products that use this compound as a sunscreen. (SRC)