다이메틸 지방질

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.

The potential developmental effects of inhalation of dibasic esters (DBE) were investigated in the rat. The DBE mixture consisted of 65.12% dimethyl-glutarate, 17.75% dimethyl-succinate and 16.83% dimethyl-adipate. Starting at Day seven of gestation, pregnant Crl:CD-BR-rats were exposed whole body to dibasic esters at 0.16, 0.4 or 1.0 mg/l for 6 hours/day. On Day 21 of gestation, female rats were euthanized, and the fetuses were examined for external, visceral and skeletal alterations. Feed consumption during the first 6 days and body weight were reduced in pregnant rats in the 0.4 and 1.0 mg/l groups. Perinasal staining and wet fur were seen in the 1.0 mg/l group. Adverse reproductive effects of dibasic esters exposure were not detected, and there was no effect on fetal weight. No significant differences were seen in the incidences of external, visceral and skeletal alterations in exposed and control fetuses. The authors conclude that dibasic esters is not a developmental toxicant by inhalation in the rat at concentrations as high as 1.0 mg/l.

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 11(SRC), determined from a structure estimation method(2), indicates that dimethyl adipate is expected to have very high mobility in soil(SRC). Volatilization of dimethyl adipate from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 9.77X10-7 atm-cum/mole(4), determined from a fragment constant estimation method(4). Dimethyl adipate is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 0.06 mm Hg(3).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 11(SRC), determined from an estimation method(2), indicates that dimethyl adipate is not expected to adsorb to suspended solids and sediment in water(SRC). Volatilization from water surfaces is not expected(3) based upon an estimated Henry's Law constant of 9.77X10-7 atm-cu m/mole(7), developed using a fragment constant estimation method(7). According to a classification scheme(4), an estimated BCF of 1.2(SRC), from a log Kow of 1.03(6) and a regression-derived equation(5), suggests the potential for bioconcentration in aquatic organisms is low. Dimethyl adipate is expected to undergo hydrolysis producing hexanedioic acid and methanol(SRC). Estimated hydrolysis half-lives are 2 years and 60 days at pH values of 7 and 8, respectively(8).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), dimethyl adipate, which has a vapor pressure of 0.06 mm Hg at 25 °C(3), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase dimethyl adipate 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 4 days(SRC), calculated from its rate constant of 4X10-12 cu cm/molecule-sec at 25 °C(2). Dimethyl adipate may undergo direct photolysis in the environment, since this compound contains a functional group that can absorb light >290 nm(4).

The Koc of dimethyl adipate is estimated as 11(SRC), using a log Kow of 1.03(3) and a regression-derived equation(1). According to a classification scheme(2), this estimated Koc value suggests that dimethyl adipate is expected to have very high mobility in soil.

GENERAL TOXICITY OF /HIGHER-MOLECULAR-WT DIESTERS OF ADIPIC ACID/...IS SIMILAR IN MANY WAYS TO THAT OF PHTHALATE ESTERS &, IN SOME INSTANCES...MAY BE LESS. TOXICITY DATA ON ADIPATES...NOT QUITE AS EXTENSIVE AS FOR PHTHALATE ESTERS, & THUS CAUTION SHOULD BE TAKEN IN CONCLUDING THAT TOXIC EFFECTS...SIMILAR. /ADIPATE ESTERS/

An estimated BCF of 1.2 was calculated for dimethyl adipate(SRC), using a log Kow of 1.03(3) and a regression-derived equation(1). According to a classification scheme(2), this BCF suggests the potential for bioconcentration in aquatic organisms is low.

The Henry's Law constant for dimethyl adipate is estimated as 9.77X10-7 atm-cu m/mole(SRC) using a fragment constant estimation method(1). This Henry's Law constant indicates that dimethyl adipate is not expected to volatilize from water surfaces(2). Dimethyl adipate's Henry's Law constant(1) indicates that volatilization from moist soil surfaces is not expected to occur(SRC). Dimethyl adipate is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 0.06 mm Hg (3).