Butyl-3,4-dihydro-2,2-dimethyl-4-oxo-2H-pyran-6-carboxylat

IN GENERAL, MATERIALS WHICH ARE TOXIC AS STORED OR WHICH CAN DECOMP INTO TOXIC COMPONENTS ... SHOULD BE STORED IN A COOL, WELL-VENTILATED PLACE, OUT OF DIRECT RAYS OF THE SUN, AWAY FROM AREAS OF HIGH FIRE HAZARD, & SHOULD BE PERIODICALLY INSPECTED. ... INCOMPATIBLE MATERIALS SHOULD BE ISOLATED FROM EACH OTHER.

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 10(SRC), determined from a structure estimation method(2), indicates that indalone is expected to have very high mobility in soil(SRC). Volatilization of indalone from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 4.7x10-8 atm-cu m/mole(SRC), using a fragment constant estimation method(3). Indalone is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 2.5X10-4 mm Hg(SRC), determined from a fragment constant method(4).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 10(SRC), determined from a structure estimation method(2), indicates that indalone 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 4.7X10-8 atm-cu m/mole(SRC), developed using a fragment constant estimation method(4). Hydrolysis is not expected to be an important fate process based on half-lives of 132 and 13 years(SRC), estimated from a structure estimation method(5). According to a classification scheme(6), an estimated BCF of 15(SRC), from an estimated log Kow of 2.42(7) and a regression-derived equation(8), suggests the potential for bioconcentration in aquatic organisms is low.

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), indalone, which has an estimated vapor pressure of 2.5X10-4 mm Hg at 25 °C is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase indalone is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals and ozone molecules(SRC). The half-life for this reaction with hydroxyl radicals in air is estimated to be 9 hours(SRC), calculated from its rate constant of 4.4X10-11 cu cm/molecule-sec at 25 °C determined using a structure estimation method(3). The half-life for this reaction with ozone is estimated to as 31 hours(SRC), calculated from its rate constant of 8.8X10-18 cu cm/molecule-sec using a structure estimation method(3).

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

... NON-IRRITANT THOUGH CAUSING SLIGHT STINGING SENSATION, TO SOME ... WHEN APPLIED TO SKIN.

MAY BE MILDLY IRRITATING TO SKIN ON REPEATED APPLICATION. ... NO HUMAN POISONINGS ARE KNOWN.

An estimated BCF of 15 was calculated for indalone(SRC), using an estimated log Kow of 2.42(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.

The Henry's Law constant for indalone is estimated as 4.7X10-8 atm-cu m/mole(SRC) using a fragment constant estimation method(1). This Henry's Law constant indicates that indalone is expected to be essentially nonvolatile from water surfaces(2). Indalone's Henry's Law constant(1) indicates that volatilization from moist soil surfaces is not expected(SRC). Indalone is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 2.5X10-4 mm Hg (SRC), determined from a fragment constant method(3).

MILD FOCAL NECROSIS IN LIVER & KIDNEYS OF RABBITS AFTER REPEATED CUTANEOUS EXPOSURES.

IN 2-YR FEEDING TRIALS SOME GROWTH RETARDATION WAS OBSERVED IN RATS RECEIVING 80 G/KG DIET.

LOW TOXICITY WARM BLOODED ANIMALS ... THE PRESENCE OF DIBUTYL OXALATE AS IMPURITY IS OBJECTIONABLE BECAUSE OF ITS HARMFUL EFFECTS ON THE KIDNEYS WHEN APPLIED TO SKIN.

The rate constant for the vapor-phase reaction of indalone with photochemically-produced hydroxyl radicals has been estimated as 4.4X10-11 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 9 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). The rate constant for the vapor-phase reaction of indalone with ozone has been estimated as 8.8X10-18 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 31 hours at an atmospheric concentration of 7X10+11 ozone molecules per cu cm(2). A base-catalyzed second-order hydrolysis rate constant of 1.7X10-3 L/mole-sec(SRC) was estimated using a structure estimation method(3); this corresponds to half-lives of 132 and 13 years at pH values of 7 and 8, respectively(3). Indalone may undergo direct photolysis since this compound contains functional groups that may absorb light in the environmental UV spectrum (>290 nm)(4), but the kinetics of this reaction are not known.

Occupational exposure and general population exposure should be low or non-existent since indalone is no longer produced or used. In the past, indalone was applied directly to the skin as an insect repellant and exposure to this compound was primarily by dermal routes. (SRC)

Indalone's former production and use as an insect repellent resulted in its direct release to the environment. If released to air, an estimated vapor pressure of 2.5X10-4 mm Hg at 25 °C indicates indalone will exist solely as a vapor in the ambient atmosphere. Vapor-phase indalone will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals and ozone molecules. The half-life for this reaction with hydroxyl radicals is estimated to be 9 hours and the half-life for the reaction with ozone is estimated to be 31 hours. If released to soil, indalone 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 based upon an estimated Henry's Law constant of 4.7X10-8 atm-cu m/mole. Indalone is not expected to volatilize from dry soil surfaces based on its vapor pressure. If released into water, indalone 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 not expected to be an important environmental fate process based on estimated half-lives of 132 and 13 years at pH 7 and 8, respectively. An estimated BCF of 15 suggests the potential for bioconcentration in aquatic organisms is low. Occupational exposure and general population exposure should be low or non-existent since indalone is no longer produced or used. In the past, indalone was applied directly to the skin as an insect repellant and exposure to this compound was primarily by dermal routes. (SRC)

LD50 Rat oral 7400 mg/kg

LD50 Mouse oral 11,600 mg/kg

LD50 Rabbit oral 5400 mg/kg

LD50 Guinea pig oral 3200 mg/kg

As the federal pesticide law FIFRA directs, EPA is conducting a comprehensive review of older pesticides to consider their health and environmental effects and make decisions about their future use. Under this pesticide reregistration program, EPA examines health and safety data for pesticide active ingredients initially registered before November 1, 1984, and determines whether they are eligible for reregistration. In addition, all pesticides must meet the new safety standard of the Food Quality Protection Act of 1996. Pesticides for which EPA had not issued Registration Standards prior to the effective date of FIFRA, as amended in 1988, were divided into three lists based upon their potential for human exposure and other factors, with List B containing pesticides of greater concern and List D pesticides of less concern. Butyl 3,4-dihydro-2,2-dimethyl-4-oxo-2H-pyran-6-carboxylate is found on List C. Case No: 3079; Pesticide type: insecticide; Case Status: No products containing the pesticide are actively registered ... The case /is characterized/ as "cancelled." Under FIFRA, pesticide producers may voluntarily cancel their registered products. EPA also may cancel pesticide registrations if registrants fail to pay required fees or make/meet certain reregistration commitments, or if EPA reaches findings of unreasonable adverse effects.; Active ingredient (AI): Butyl 3,4-dihydro-2,2-dimethyl-4-oxo-2H-pyran-6-carboxylate; AI Status: The active ingredient is no longer contained in any registered pesticide products ... "cancelled."