N-Methylacetamide

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.

SIMULTANEOUS TREATMENT OF PREGNANT RATS WITH SODIUM NITRITE IN DRINKING WATER & N-METHYLACETAMIDE PRODUCED GREATER TERATOGENIC EFFECTS THAN TREATMENT WITH N-METHYLACETAMIDE ALONE. THUS, ENDOGENOUS NITRATION OF CMPD MAY BE TERATOGENIC FACTOR.

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 6(SRC), determined from a log Kow of -1.05(2) and a regression-derived equation(3), indicates that N-methylacetamide is expected to have very high mobility in soil(SRC). Volatilization of N-methylacetamide from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 4.23X10-8 atm-cu m/mole(SRC), derived from its vapor pressure, 0.44 mm Hg(4), and water solubility, 1.0X10+6 mg/l(5). N-Methylacetamide is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 0.44 mm Hg(4). N-Methylacetamide (at 100 ppm), exposed to an activated sludge inoculum for two weeks under aerobic conditions, was categorized as biodegradable(6) and is expected to biodegrade in soil(SRC).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 6(SRC), determined from an measured log Kow of -1.05(2) and a regression-derived equation(3), indicates that N-methylacetamide 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 4.23X10-8 atm-cu m/mole(SRC), derived from its vapor pressure, 0.44 mm Hg(4), and water solubility, 1.0X10+6 mg/l(5). According to a classification scheme(6), an estimated BCF of 3(SRC), from its log Kow(2) and a regression-derived equation(7), suggests the potential for bioconcentration in aquatic organisms is low(SRC). N-Methylacetamide (at 100 ppm), exposed to an activated sludge inoculum for two weeks under aerobic conditions, was categorized as biodegradable(8), and is expected to biodegrade in water(SRC). N-Methylacetamide (at 50 ppm carbon), under anaerobic conditions, was not biodegraded over a 4 week period using a 10% activated sludge inoculum(9).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), N-methylacetamide, which has a vapor pressure of 0.44 mm Hg at 23 °C(2), is expected to exist solely as a vapor in the ambient atmosphere(SRC). Vapor-phase N-methylacetamide 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 3.1 days(SRC), calculated from its rate constant of 5.2X10-12 cu cm/molecule-sec at 25 °C(3).

The Koc of N-methylacetamide is estimated as 6(SRC), using a log Kow of -1.05(1) and a regression-derived equation(2). According to a classification scheme(3), this estimated Koc value suggests that N-methylacetamide is expected to have very high mobility in soil(SRC).

/Liver toxicity was assessed in/ workers /exposed/ to N,N-dimethylacetamide (DMAC) in an acrylic fiber manufacturing facility. /Measurements were made/ over a 1 yr study period. ... Evidence of liver toxicity was assessed by serum clinical chemistry tests (serum levels of total bilirubin, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, & gamma-glutamyl transpeptidase) at least once during the study period for all 127 male workers in the two study departments & for 217 male in plant controls with no previous or current exposure to DMAC. If a worker's biomonitoring results exceeded one of two trigger values established for the study (60 mg N-methylacetamide/g creatinine or 136 mg DMAC equivalent/g creatinine), addnl serum clinical chemistry tests were conducted at weekly intervals for 3 wk. DMAC exposed workers were classified as either high exposure, if 1 or more biomonitoring result exceeded one of the trigger values, or unspecified exposure if none of them did. Control group employees were classified as no exposure. Mean DMAC in air levels for the high & unspecified exposure groups appeared to differ (geometric mean DMAC in air levels of 1.9 & 1.3 ppm 12 hr time weighted avg, respectively). No significant DMAC exposure related trends in hepatic serum clinical chemistry results were detected. Neither transient incr in serum analyte levels after a high biomonitoring result (one that exceeded a trigger value) nor an elevated mean level over the study period when compared with in plant controls were observed. These results /indicate/ that brief threshold limit value level exposures & chronic low level exposure (maximum likelihood estimate of the arithmetic mean for DMAC in air for the high exposure group over the study period was 3.0 ppm 12 hr time weighted avg) do not cause hepatotoxic clinical chemistry responses. /N,N-dimethylacetamide/

AEROBIC: N-Methylacetamide (at 100 ppm), exposed to an activated sludge inoculum for two weeks under aerobic conditions, was categorized as biodegradable(1). ANAEROBIC: N-Methylacetamide (at 50 ppm carbon), under anaerobic conditions, was not biodegraded over a 4 week period using a 10% activated sludge inoculum(2).

An estimated BCF of 2 was calculated for N-methylacetamide(SRC), using a log Kow of -1.05(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 N-methylacetamide is estimated as 4.23X10-8 atm-cu m/mole(SRC) based upon its vapor pressure, 0.44 mm Hg(1), and water solubility, 1.0X10+6 mg/l(2). This Henry's Law constant indicates that N-methylacetamide is expected to be essentially nonvolatile from water surfaces(3). N-Methylacetamide is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 0.44 mm Hg(1).

6 AMIDE-TYPE SOLVENTS INCLUDING N-METHYLACETAMIDE WERE APPLIED TO SKIN OF PREGNANT RATS DURING PERIOD OF FETAL ORGANOGENESIS. SLIGHT TERATOGENIC EFFECTS WERE DEMONSTRATED & SLIGHT EMBRYO MORTALITY WAS FOUND WITH N-METHYLACETAMIDE.

WHEN AQUEOUS SOLN OF ACETAMIDES & FORMAMIDES WERE ADMIN BY STOMACH TUBE TO PREGNANT RABBITS FROM 6TH TO 18TH DAY PAST INSEMINATION. BOTH THE ADULT RABBITS AND THE FETUSES WERE EXAMINED FOR EMBRYOTOXIC OR TERATOGENIC EFFECTS. THIS INCLUDED BODY WEIGHT AND WEIGHT GAIN, CONCEPTION RATE, MALFORMATION OF FETUSES, AND THE NUMBERS OF LIVING AND DEAD EMBRYOS PER RABBIT. FOR THE ACETAMIDE DERIVATIVES, THE MONOMETHYL DERIVATIVE HAD THE GREATEST TERATOGENIC EFFECT.

ANIMALS WHICH DIED 24-48 HR AFTER ADMIN OF N-METHYLACETAMIDE HAD TOXIC HEPATITIS, NECROSIS OF PANCREAS & SPLEEN LYMPHOCYTES, & TESTICULAR ATROPHY IN MICE.

SC INJECTIONS OF N-MONOMETHYLACETAMIDE 10 ML OF A 12% SOLN/KG/DAY FOR 4 DAYS INTO NORMAL & ADRENALECTOMIZED RATS PRODUCED HYPERGLYCEMIA DUE TO REDUCED EFFECTIVENESS OF ENDOGENOUS INSULIN.

For more Non-Human Toxicity Excerpts (Complete) data for N-METHYLACETAMIDE (13 total), please visit the HSDB record page.

The rate constant for the vapor-phase reaction of N-methylacetamide with photochemically-produced hydroxyl radicals is 5.20X10-12 cu cm/molecule-sec at 27 °C(1). This corresponds to an atmospheric half-life of about 3.1 days(SRC) at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(2). N-Methylacetamide is not expected to undergo hydrolysis in the environment due to the slow rate of reaction for amide functional groups nor to directly photolyze due to the lack of absorption in the environmental UV spectrum (>290 nm)(SRC).

NIOSH (NOES Survey 1981-1983) has statistically estimated that 851 workers (187 of these are female) are potentially exposed to N-methylacetamide in the US(1). Occupational exposure to N-methylacetamide may occur through inhalation and dermal contact with this compound at workplaces where N-methylacetamide is produced or used(SRC).