デヒドロ酢酸

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 recommended classification scheme(1), an estimated Koc value of 120(SRC), determined from a measured water solubility of 690 mg/l(2) and a recommended regression-derived equation(3), indicates that dehydroacetic acid is expected to have high mobility in soil(SRC). Volatilization of dehydroacetic acid from moist soil surfaces is not expected to be important(SRC) given an estimated Henry's Law constant of 3.4X10-7 atm-cu m/mole(SRC), determined from its measured water solubility, 690 mg/l(2), and extrapolated vapor pressure, 1.1X10-3 mm Hg(4). Dehydroacetic acid is not expected to volatilize from dry soil surfaces based on its extrapolated vapor pressure(4). Biodegradation of dehydroacetic acid in soil may be important(SRC), based on its biodegradation in standard biodegradability tests(2,5).

AQUATIC FATE: Based on a recommended classification scheme(1), an estimated Koc value of 120(SRC), a measured water solubility of 690 mg/l(2) and a recommended regression-derived equation(3), indicates that dehydroacetic acid is not expected to adsorb to suspended solids and sediment in water(SRC). Dehydroacetic acid is not expected to volatilize from water surfaces(3,SRC) based on an estimated Henry's Law constant of 3.4X10-7 atm-cu m/mole(SRC), from its measured water solubility, 690 mg/l(2), and extrapolated vapor pressure, 1.1X10-3 mm Hg(4). According to a classification scheme(5), an estimated BCF value of 15(3,SRC), from a measured water solubility(2), suggests that bioconcentration in aquatic organisms is low(SRC). A biodegradation study on dehydroacetic acid, based on BOD measurements, using an activated sludge seed, and an initial chemical concentration of 100 mg/l indicated 84% biodegradation after 2 weeks(2). Dehydroacetic acid was observed to degrade in six aerobic biodegradation tests (coupled units test, Zahn-Wellens test, MITI test, Sturm CO2 evolution test, OECD screening test, and closed bottle test)(6).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), dehydroacetic acid, which has an extrapolated vapor pressure of 1.1X10-3 mm Hg at 25 °C(2,SRC), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase dehydroacetic acid 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 about 4.9 hours(3,SRC). The rate constant for the vapor-phase reaction of dehydroacetic acid with ozone has been estimated as 1.1X10-17 cu cm/molecule-sec at 25 °C(3,SRC). This corresponds to an atmospheric half-life of about 1.0 day at an atmospheric ozone concn of 7X10+11 cu cm/molecule-sec at 25 °C(3,SRC).

The Koc of dehydroacetic acid is estimated as approximately 120(SRC), using a measured water solubility of 690 mg/l(1) and a regression-derived equation(2,SRC). According to a recommended classification scheme(3), this estimated Koc value suggests that dehydroacetic acid is expected to have high mobility in soil(SRC).

The mutagenicity of dehydroacetic acid was evaluated in Salmonella tester strains TA98, TA100, TA1535, TA1537 and TA1538 (Ames Test), both in the presence and absence of added metabolic activation by Aroclor-induced rat liver S9 fraction. Based on preliminary toxicity determinations, dehydroacetic acid, diluted in water, was tested at concentrations up to 8mg/plate using the plate incorporation technique. Dehydroacetic acid did not cause a positive response in any tester strain with or without metabolic activation.

CAUSES IMPAIRED KIDNEY FUNCTION. LARGE DOSES CAN CAUSE VOMITING, ATAXIA, CONVULSIONS.

NO PRIMARY OR ALLERGIC SKIN REACTIONS. HUMANS INGESTED 0.01 G/KG DAILY FOR 150 DAYS WITHOUT OBSERVABLE ILL-EFFECTS.

Dehydroacetic acid's production and use in organic syntheses, as a plasticizer, bactericide, in anti-enzyme toothpastes(1), and as a fungicide in cosmetics and on processed fruits and vegetables(2) may result in its release to the environment(SRC).

A biodegradation study on dehydroacetic acid, based on BOD measurements, using an activated sludge seed, and an initial chemical concentration of 100 mg/l indicated 84% biodegradation after 2 weeks(1). Dehydroacetic acid was observed to degrade in six aerobic biodegradation tests (coupled units test, Zahn-Wellens test, MITI test, Sturm CO2 evolution test, OECD screening test, and closed bottle test)(2). 99% DOC removal was observed in the coupled units test using a sewage seed; 96% DOC removal was observed after 6 days using an activated sludge seed in the Zahn-Wellens test; 91% DOC removal was observed after 14 days incubation using an activated sludge seed in the MITI test; 100% DOC removal was observed after 28 days incubation using a sewage seed in the Sturm test; 98% DOC removal was observed after 19 days incubation using a sewage seed in the OECD screening test; and 81% BODT was observed after 28 days using a sewage seed in the closed bottle test(2).

An estimated BCF value of 15 was calculated for dehydroacetic acid(SRC), using a measured water solubility of 690 mg/l(1) and a recommended regression-derived equation(2). According to a classification scheme(3), this BCF value suggests that bioconcentration in aquatic organisms is low(SRC).

The Henry's Law constant for dehydroacetic acid is estimated as 3.4X10-7 atm-cu m/mole(SRC) from its extrapolated vapor pressure, 1.1X10-3 mm Hg(1), and measured water solubility, 690 mg/l(2). This value indicates that dehydroacetic acid will volatilize very slowly from water surfaces(3,SRC). 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) is estimated as approximately 140 days(3,SRC). The volatilization half-life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec) is estimated as approximately 1030 days(3,SRC). Dehydroacetic acid's Henry's Law constant(1,2,SRC) indicates that volatilization from moist soil surfaces is not expected to be important(SRC). Dehydroacetic acid is not expected to volatilize from dry soil surfaces based on an extrapolated vapor pressure of 1.1X10-3 mm Hg(1,SRC).

AT HIGH DOSAGE LEVELS MONKEYS SHOWED ANOREXIA, VOMITING, WEAKNESS, STUPOR, ATAXIA, & CONVULSIONS.

...LOSS OF WEIGHT IN RATS FED WITH 0.3 G/KG OVER 34 DAYS BUT NO ILL-EFFECTS AT 0.1 G/KG FOR OVER 2 YR.

SODIUM DEHYDROACETATE (120-300 MG/KG/DAY FOR 3 OR 7 DAYS IP) GIVEN TO MICE INCR LIPID DROPLETS IN CENTRILOBULAR & MIDLOBULAR HEPATOCYTES. IT PRODUCED LITTLE OR NO PROLIFERATION OF SMOOTH ENDOPLASMIC RETICULUM IN HEPATOCYTES & LITTLE INCR IN DRUG-METAB ENZYME ACTIVITY. /SODIUM DEHYDROACETATE/

Dehydroacetic acid 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.

Dehydroacetic acid is an indirect food additive for use as a component of adhesives.