4'-tert-Butyl-2',6'-dimethyl-3',5'-dinitroacetophenon

Fragrance Ingredient (Musk ketone) -> IFRA transparency List

Fragrance -> musk

log Kow = 4.30

4.30

Sweet, very persistent, slightly animal musk odor

Unique ... powdery

Insoluble (<1 mg/ml at 68.0 °F) (NTP, 1992)

In water, 0.46 mg/L at 25 °C

Very soluble in chloroform

0.00046 mg/mL

274.1 to 277.7 °F (NTP, 1992)

135.5 °C

135.5 - 136 °C

Warning

H351: Suspected of causing cancer [Warning Carcinogenicity]

P203, P273, P280, P318, P391, P405, and P501 (click each P-code to see the statement)

Warning

H351 (99.8%): Suspected of causing cancer [Warning Carcinogenicity]

P203, P273, P280, P318, P391, P405, and P501 (click each P-code to see the statement)

Chemical: Ethanone, 1-[4-(1,1-dimethylethyl)-2,6-dimethyl-3,5-dinitrophenyl]-

Ethanone, 1-[4-(1,1-dimethylethyl)-2,6-dimethyl-3,5-dinitrophenyl]- is listed on the EPA's Chemical Data Reporting (CDR) system. Manufacturers and importers of Ethanone, 1-[4-(1,1-dimethylethyl)-2,6-dimethyl-3,5-dinitrophenyl]- are required to report information about their production and use of this chemical to the EPA under the Toxic Substances Control Act (TSCA). (40 eCFR Part 711)

REACH registered substance: 4'-tert-butyl-2',6'-dimethyl-3',5'-dinitroacetophenone (EC: 201-328-9)

Ethanone, 1-4-(1,1-dimethylethyl)-2,6-dimethyl-3,5-dinitrophenyl-: Does not have an individual approval but may be used under an appropriate group standard

A nitrated ketone. Ketones are reactive with many acids and bases liberating heat and flammable gases (e.g., H2). The amount of heat may be sufficient to start a fire in the unreacted portion of the ketone. Ketones react with reducing agents such as hydrides, alkali metals, and nitrides to produce flammable gas (H2) and heat. Ketones are incompatible with isocyanates, aldehydes, cyanides, peroxides, and anhydrides. They react violently with aldehydes, HNO3, HNO3 + H2O2, and HClO4.

Carc. 2 (99.8%)

Carcinogenicity - category 2

Reproductive toxicity - Category 2

Carc. 2

EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.

Suitable extinguishing media: Use water spray, alcohol-resistant foam, dry chemical or carbon dioxide.

Advice for firefighters: Wear self contained breathing apparatus for fire fighting if necessary.

ACCIDENTAL RELEASE MEASURES: Personal precautions, protective equipment and emergency procedures: Use personal protective equipment. Avoid dust formation. Avoid breathing vapors, mist or gas. Ensure adequate ventilation. Evacuate personnel to safe areas. Avoid breathing dust. Environmental precautions: Prevent further leakage or spillage if safe to do so. Do not let product enter drains. Discharge into the environment must be avoided. Methods and materials for containment and cleaning up: Pick up and arrange disposal without creating dust. Sweep up and shovel. Keep in suitable, closed containers for disposal.

SMALL SPILLS AND LEAKAGE: You should dampen the solid spill material with acetone, then transfer the dampened material to a suitable container. Use absorbent paper dampened with acetone to pick up any remaining material. Seal your contaminated clothing and the adsorbent paper in a vapor-tight plastic bag for eventual disposal. Solvent wash all contaminated surfaces with acetone followed by washing with a strong soap and water solution. Do not reenter the contaminate area until the Safety Officer (or other responsible person) has verified that the area has been properly cleaned.

SRP: Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in air, soil or water; effects on animal, aquatic and plant life; and conformance with environmental and public health regulations. If it is possible or reasonable use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination.

Product: Offer surplus and non-recyclable solutions to a licensed disposal company. Contact a licensed professional waste disposal service to dispose of this material. Dissolve or mix the material with a combustible solvent and burn in a chemical incinerator equipped with an afterburner and scrubber; Contaminated packaging: Dispose of as unused product.

ACCIDENTAL RELEASE MEASURES: Personal precautions, protective equipment and emergency procedures: Use personal protective equipment. Avoid dust formation. Avoid breathing vapors, mist or gas. Ensure adequate ventilation. Evacuate personnel to safe areas. Avoid breathing dust. Environmental precautions: Prevent further leakage or spillage if safe to do so. Do not let product enter drains. Discharge into the environment must be avoided.

Precautions for safe handling: Avoid contact with skin and eyes. Avoid formation of dust and aerosols. Provide appropriate exhaust ventilation at places where dust is formed.

Appropriate engineering controls: Handle in accordance with good industrial hygiene and safety practice. Wash hands before breaks and at the end of workday.

Gloves must be inspected prior to use. Use proper glove removal technique (without touching glove's outer surface) to avoid skin contact with this product. Dispose of contaminated gloves after use in accordance with applicable laws and good laboratory practices. Wash and dry hands.

For more Preventive Measures (Complete) data for Musk ketone (6 total), please visit the HSDB record page.

RECOMMENDED RESPIRATOR: Where the neat test chemical is weighed and diluted, wear a NIOSH-approved half face respirator equipped with an organic vapor/acid gas cartridge (specific for organic vapors, HCl, acid gas and SO2) with a dust/mist filter. (NTP, 1992)

Eye/face protection: Safety glasses with side-shields conforming to EN166. Use equipment for eye protection tested and approved under appropriate government standards such as NIOSH (US) or EN 166(EU).

Skin protection: Handle with gloves.

Body Protection: Impervious clothing. The type of protective equipment must be selected according to the concentration and amount of the dangerous substance at the specific workplace.

Respiratory protection: Where risk assessment shows air-purifying respirators are appropriate use a full-face particle respirator type N100 (US) or type P3 (EN 143) respirator cartridges as a backup to engineering controls. If the respirator is the sole means of protection, use a full-face supplied air respirator. Use respirators and components tested and approved under appropriate government standards such as NIOSH (US) or CEN (EU).

Musk ketone was detected in 4 of 4 human adipose tissues samples, obtained from cadavers in Switzerland at autopsy, in 1983-84 and 10 of 11 samples collected in 1994 at concentrations ranging from 4.2 to 40 ng/g and 0.71 to 173 ng/g in samples from 1983-84 and 1994 respectively(1). Musk ketone was detected at 0.01 to 0.03 mg/kg fat in 19 human adipose tissue samples from males collected in Scheswig-Holstein (Germany) from May-June 1993 and at 0.01 to 0.22 mg/kg fat in 13 human adipose tissue samples from females collected in Scheswig-Holstein (Germany) from July 1992(2). Musk ketone was detected in 98% of milk samples from nursing mothers living in Southern Bavaria in 1992 (48 samples) and 1993 (343 samples) between <0.01-0.24 mg/kg fat with a mean concentration of 0.04 mg/kg fat(3). Musk ketone was at 0.01 to 0.09 mg/kg fat in 23 milk samples from nursing mothers from Scheswig-Holstein (Germany) from February 1992 to June 1993(4). Musk ketone was not detected in any maternal serum samples or umbilical cord serum samples collected from 20 mothers in Seoul, Korea, sampling dates not provided(5). The compound was detected in adipose tissue of 81% of Korean women evaluated between May 2007 and May 2008, at a mean concentration of 13 ng/g, median 12 ng/g, and range <2-34 ng/g(6).

... 13 patients, suspected to suffer from a photoallergic contact dermatitis, were screened by means of a questionnaire and clinical tests. Dermal sensitivity to UV light was pre-tested after which nitromusks (amount and vehicle not specified) were applied on the skin under occlusive patches (two sites per substance). After 24 hours of contact the patches were removed under dim light and the skin examined for any signs of contact-dermatitis. Half of the contact sites were covered again and the other half was irradiated with ultra-violet light. All persons studied showed a photoallergic reaction to musk ambrette. In one person also a photoallergic reaction to musk ketone was observed. No reaction was seen at the non-irradiated site. The study is inconclusive as to whether this patient shows either cross-photoallergy between musk ambrette and musk ketone or that this patient shows a concomittant independent photo-allergy to two nitromusks. The study is also inconclusive as to the prevalence of the condition.

... When the cells were treated simultaneously with MK (5-5000 ng/mL) and 0.2 ug/mL benzo(a)pyrene, no synergistic effects were detected; benzo(a)pyrene (B(a)P) itself caused an 1.5-fold increase of MN over the spontaneous background frequency (60 versus 39 MN/1000 binucleated cells). ...

When tested in an in vitro micronucleus test with metabolically competent human hepatoma cells (Hep G2 line), a cogenotoxic effect of musk ketone was observed when the cells were pre-treated with musk ketone for 28 hours and subsequently exposed to B(a)P, but not when the cells were simultaneously treated with musk ketone and B(a)P. Pretreatment with musk ketone resulted in a significant increase in B(a)P-induced micronuclei. This amplification of B(a)P genotoxicity was seen with 500-5,000 ng/mL musk ketone, concentrations that were effectively inducing CYP1A-activities (as was shown by EROD measurements in the Hep G2 cells), i.e. enzymes playing a key role in the activation of B(a)P.

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 8700(SRC), determined from a log Kow of 4.3(2) and a regression-derived equation(3), indicates that musk ketone is expected to be immobile in soil(SRC). Volatilization of musk ketone from moist soil surfaces may be an important, relatively slow, fate process(SRC) given an estimated Henry's Law constant of 2.5X10-7 atm-cu m/mole(4) derived from its vapor pressure, 3.0X10-7 mm Hg(5), and water solubility, 0.46 mg/L(5). Additionally, adsorption to soil is expected to attenuate volatilization(SRC). Musk ketone is not expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(5). A 0% of theoretical BOD using activated sludge in the Japanese MITI test(6) suggests that biodegradation is not an important environmental fate process in soil(SRC).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 8700(SRC), determined from a log Kow of 4.3(2) and a regression-derived equation(3), indicates that musk ketone is expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is not expected(4) based upon an estimated Henry's Law constant of 2.5X10-7 atm-cu m/mole(5) derived from its vapor pressure, 3.0X10-7 mm Hg(6), and water solubility, 0.46 mg/L(6). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 170 days and > 1 year, respectively(SRC). According to a classification scheme(7), a BCF of 1380(8) suggests bioconcentration in aquatic organisms is very high(SRC). A 0% of theoretical BOD using activated sludge in the Japanese MITI test(8) suggests that biodegradation is not an important environmental fate process in water(SRC).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), musk ketone, which has a vapor pressure of 3.0X10-7 mm Hg at 25 °C(2), is expected to exist in both the vapor and particulate phases in the ambient atmosphere. Vapor-phase musk ketone 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 25 days(SRC), calculated from its rate constant of 1.3X10-12 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). Particulate-phase musk ketone may be removed from the air by wet and dry deposition(SRC). Musk ketone contains chromophores that absorb at wavelengths >290 nm(4) and, therefore, may be susceptible to direct photolysis by sunlight(SRC).

ENVIRONMENTAL: Musk ketone was detected in 98% of milk samples from nursing mothers living in Southern Bavaria in 1992 (48 samples) and 1993 (343 samples) between <0.01-0.24 mg/kg fat with a mean concentration of 0.04 mg/kg fat(1). Musk ketone was at 0.01 to 0.09 mg/kg fat in 23 milk samples from nursing mothers from Scheswig-Holstein (Germany) from February 1992 to June 1993(2).

In a 1993/5 survey of human milk (n=73 samples from different European countries), musk ketone was present at concentrations ranging from approximately 20-130 ug /kg milk fat, with a mean of approximately 25 ug/kg milk fat. The mean fat content of the milk was 3.1%(1). In a 1999 survey of human milk samples from 10 mothers in Denmark, musk ketone was present at concentrations ranging from below the detection limit to 26.9 ug/kg with a mean concentration of 17.0 ug/kg milk fat(2). Musk ketone was detected in 11 of 20 human milk samples from Seoul, Korea, at concentrations ranging from 0.015-0.15 with a mean concentration of 0.057, sampling dates not provided(3). Musk ketone was below the limit of quantification in 83 of 101 samples of human milk collected from 1996 to 2003 and detected in 18 samples at concentrations up to 24.4 ng/g lipid(4).

From 108 women, milk was taken and analyzed for several polycyclic musks and Nitromusks ... The women were also asked to report on their use of fragranced cosmetics and household products as well as their fish consumption. A mean and a median fat content of 3.67 and 3.40%, respectively, were found in the mother's milk. The concentration of musk ketone in the milk showed a mean value of 3.49 ug/kg milk fat with a standard deviation of 9.24. The minimum and maximum value found were close to zero (detection limit /less than/ 2 ug/kg milk fat) and 82.9 ug/kg milk fat, respectively. There was no convincing correlation of musk ketone levels in the milk with maternal age, body mass, loss of body mass and weight and pregnancy and lactation variables. It was stated that there was a significant correlation with the use of skin products, but not with fish consumption (this could not be verified as the report was not complete). ... Milk samples (391) from nursing mothers living in Southern Bavaria (Germany) were analyzed for musk ketone in 1991 (48 samples) and 1992 (343 samples). Levels of musk ketone varied from /less than/ 10 to 240 ug/kg milk fat, with a mean of 40 ug/kg milk fat (90- and 95- percentile 80 and 110 ug/kg milk fat, respectively).

IDENTIFICATION AND USE: Musk ketone forms yellow crystals. It is a fragrance. Musk ketone is widely used as a fixative in blossom and fantasy compositions. HUMAN STUDIES: Musk ketone failed to elicit a sensitization reaction after 48 and 72 hours in a maximization test with human volunteers. A case described patient with chronic actinic dermatitis whose photopatch tests revealed reactions to musk ketone and musk ambrette, both of which were found in his aftershave lotion. Musk ketone at doses of 0.068 to 68 uM did not induce sister chromatid exchanges in human lymphocytes with or without metabolic activation. In an in vitro micronucleus test, musk ketone at doses up to 136 and 250 uM did not increase the frequency of micronuclei in human lymphocytes and in the human hepatoma cell line Hep G2, respectively. ANIMAL STUDIES: Musk ketone did not produce dermal irritation or systemic toxicity in rabbits. It was a mild eye irritant in rabbit's eyes. Musk ketone did not produce contact sensitivity in guinea pigs. Musk ketone treatment in mice resulted in dose-related increases in relative liver weight at dose levels of 50 mg/kg bw, up to 50% at 500 mg/kg bw. Musk ketone also caused histological changes in the liver, primarily centrilobular hepatocellular hypertrophy, and at the highest dose panlobular hepatocellular hypertrophy. Pregnant rats received by gavage 0, 60, 200, 600 or 2,000 mg musk ketone/kg bw/day during days 7-17 of gestation. Observations after caesarean sectioning showed decreases in fetal body weights, litter sizes and live fetuses and increases in early and late resorptions and percent resorbed conceptuses at 200 mg/kg bw and higher. No gross external fetal alterations were observed. Musk ketone negatively affects reproduction and early life-stage survival in zebrafish. Musk ketone was tested in 5 strains of Salmonella typhimurium and found to be negative with and without activation. ECOTOXICITY STUDIES: Cytochromes P450 are potentially sensitive targets of synthetic musk substances in fish.

/AQUATIC SPECIES/ Synthetic musks are widely used as perfuming agents in products, such as cosmetics, detergents, and soaps. The increased detection of these substances in the aquatic environment and their high bioconcentration potential raises concerns about potential effects on aquatic species. This work aimed at assessing the interactions of the most widely used musks: nitromusks (musk xylene, musk ketone) and polycyclic musks (celestolide, galaxolide, and tonalide) with fish enzymatic systems involved in both xenobiotic and endogenous metabolism. Therefore, CYP catalyzed pathways were investigated in carp liver microsomes (CYP1A, CYP3A), ovarian microsomes (CYP19) and testicular mitochondria (CYP17 and CYP11beta) using standard substrates. Phase II activities (UDP-glucuronosyltransferases and sulfotransferases) were determined in carp liver microsomes and cytosol, respectively. Polycyclic musks (galaxolide and tonalide) were stronger inhibitors of CYP3A- (IC(50): 68-74 uM), CYP17- (IC(50): 213-225 uM), CYP11beta- and CYP19-catalyzed activities than nitromusks, while the latter showed higher ability to interfere with CYP1A (IC(50): 35-37 uM). The sulfation of estradiol was also significantly inhibited by tonalide and galoxolide (IC(50): 140-294 uM). Overall, polycyclic musks showed the highest potential to interfere with those activities involved in the synthesis and metabolism of steroids while nitromusks mainly interfered with xenobiotic metabolism (CYP1A-catalyzed reactions). The obtained data suggest that CYP isoforms are potentially sensitive targets of synthetic musk substances in fish.

/AQUATIC SPECIES/ Toxicity tests of musk ketone (MK) and tetrabromobisphenol-A (TBBPA) on embryos were conducted in two amphibian species, Xenopus (Silurana) tropicalis and the Swedish native species Rana arvalis. TBBPA was also tested on fish embryos of Danio rerio. All species were tested in similar experimental setup. Musk ketone caused decreased heart rates at concentrations from 10 and 100 ug/L in R. arvalis and X. tropicalis, respectively. TBBPA caused effects at 1000 ug/L in all three species. The responses were comparable between all three species which supports the relevance for using data from non-native species in national risk assessment.

/AQUATIC SPECIES/ Bioaccumulation of polycyclic musks (HHCB, AHTN) and nitro musks (musk xylene, musk ketone, and their amino metabolites) in aquatic biota was investigated by analyzing 18 fish samples (rudd, tench, crucian carp, eel) and 1 pooled zebra mussel sample from the pond of a municipal sewage treatment plant. Furthermore, water samples taken at the effluent of the sewage plant as well as water samples and two series of semipermeable membrane devices (SPMDs) from the pond were included. This comprehensive data set allowed the determination of species-dependent bioaccumulation factors on a lipid basis (BAF(L)), e.g., for HHCB the BAF(L) in tench were more than 20 times higher than in eel. The BAF(L) for HHCB and AHTN in biota were lower than the partition coefficients K(SPMD/W) obtained from SPMD samples, which are assumed to represent model bioconcentration values. This stresses that metabolism of these compounds in fish must not be neglected.

/AQUATIC SPECIES/ Musk xylene (MX), musk ketone (MK) and musk moskene (MM) are synthetic nitro-containing fragrances. Due to their inherent lipophilicity and environmental persistence, they are frequently detected in environmental samples and especially in aquatic ecosystems. ... Although nitromusks have been shown to accumulate in aquatic organisms, little is known about their potential developmental effects in the respective aquatic species. To investigate the developmental toxicity of these compounds to amphibians and fish, early lifestages of xenopus (Xenopus laevis) and zebrafish (Danio rerio) were exposed to three nitromusks for 96 hr to examine the developmental effects of these compounds in the two species. Nitromusk body concentration measurements were carried out in parallel for correlation with potential developmental effects. No increased mortality, malformation or growth inhibition was observed in either species following 96-hr exposure to 400 ug/L MX, MK and MM. However, an approximately 20% reduced viability was observed in xenopus larvae when exposed to 400 ug/L MX, MK and MM for 11 days. Xenopus and zebrafish exposed to 10, 153, 871 and 1637 ug/L 14C-MX for 96 hr resulted in whole-body concentrations of 0.7 +/- 0.1, 11.1 +/- 1.1, 38.7 +/- 1.9 and 76.3 +/- 18.3 ug/g, and 4.3 +/- 0.6, 73.3 +/- 11.8, 440.0 +/- 72.7 and 664.0 +/- 47.7 ug/g wet body weight, respectively. Exposure of xenopus larvae to 400 ug/L MX, MK and MM for 11 days, resulted in whole body concentrations (extrapolated from gas chromatographic determinations) of 4700 +/- 5000, 1300 + 300 and 4600 + 4800 ug/g wet weight for MX, MK and MM, respectively. The latter toxicity results, in conjunction with the fact that the concentrations used for the above experiments were between 400- and 10000-fold higher than those detected in the environment, suggest that environmental concentrations of nitromusks are not hazardous for early lifestages of fish and amphibians.

For more Ecotoxicity Excerpts (Complete) data for Musk ketone (7 total), please visit the HSDB record page.

EPA has released the Interactive Chemical Safety for Sustainability (iCSS) Dashboard. The iCSS Dashboard provides an interactive tool to explore rapid, automated (or in vitro high-throughput) chemical screening data generated by the Toxicity Forecaster (ToxCast) project and the federal Toxicity Testing in the 21st century (Tox21) collaboration. /The title compound was tested by ToxCast and/or Tox21 assays/[USEPA; ICSS Dashboard Application; Available from, as of July 27, 2017: http://actor.epa.gov/dashboard/]

The following link will take the user to the National Toxicology Program (NTP) Test Status of Agents Search page, which tabulates the results and current status of tests such as "Short-Term Toxicity Studies", "Long-term Carcinogenicity Studies", "Developmental Studies", "Genetic Toxicology Studies", etc., performed with this chemical. Testing status for musk ketone is available.[Available from, as of June 16, 2017: https://ntpsearch.niehs.nih.gov/?e=True&ContentType=Testing+Status]

Musk ketone was detected in 18 effluent samples from 3 treatment plants along the river Tama (Japan) in 1981 at 0.14-0.41 ug/L, median concentration 0.26 ug/L(1). Musk ketone was detected in effluent samples collected over a 3-day period from an activated sludge wastewater treatment plant in Loveland, OH in Sept 1997 and from a trickling filter wastewater treatment plant in Glendale, OH in Oct 1997 at concentrations of 99 ng/L and 96 ng/L respectively(2). Musk ketone was detected in the effluent from a variety of European and U.S. wastewater treatment plants at concentrations ranging from 60 to 705 ng/L and from 19 to 67 ng/L respectively, depending on the type of wastewater treatment plant(3). Musk ketone was detected in sludge from a domestic wastewater treatment plant in Georgetown DE, in samples collected in March 2002, at a concentration of 1.3 ug/g(4). Musk ketone was identified in 7 of 12 Swiss sludge samples, mainly in sludge containing domestic sewage water, at an average concentration of 5 ug/kg(5). In the City of Lubbock, TX, musk ketone was not detected in wastewater treatment plant influents and effluents sampled in Winter 2009, Spring 2010, and Winter 2010; it was not detected in influent but detected at a concentration of 151 ng/L in effluent during Summer 2010; it was detected in influent at a concentration of 812 ng/L but not detected in effluent during Fall 2010(6). In wastewater treatment plants of Beijing, China sampled in Jan and Sept 2008, musk ketone was detected in influent at concentrations of 52.25-165.8 ng/L and in effluent at concentrations of 22.77-91.6 ng/L(7).

The Koc of musk ketone is estimated as 8,700(SRC), using a log Kow of 4.3(1) and a regression-derived equation(2). According to a classification scheme(3), this estimated Koc value suggests that musk ketone is expected to be immobile in soil.

URBAN/SUBURBAN: Musk ketone was detected in 11 of 26 air samples collected from Milwaukee (Wisconsin) in June 2001 at an average concentration of 0.093 ng/cu m; the reported concentration was not corrected for the concentration in the field blanks so the actual value is likely to be lower(1).

RURAL/REMOTE: Musk ketone was detected in 2 of 11 air samples collected from Lake Michigan from June 1991 and May 2000 at an average concentration of 0.13 ng/cu m; the reported concentration was not corrected for the concentration in the field blanks so the actual value is likely to be lower(1).

SOURCE DOMINATED: Musk ketone was not detected in air sampled at two landfills in Northern Germany in 2009(1).

/HUMAN EXPOSURE STUDIES/ Two healthy male volunteers received an application of 2.2 mg ring-labeled (14)C-musk ketone (in a mixture of phenylethyl alcohol and ethanol) on the unshaven skin of the upper left quadrant of the chest for 6 hours. The dose was applied evenly over an area of 100 sq cm. The application rate was 0.02 mg/sq cm. The treated area was covered with protective gauze held in position with adhesive tape. After 6 hours, the dressing was removed from the test area and the treated skin was wiped. Blood, urine and feces were collected up to 120 hours after start of dosing. After 120 hours the treated area of the skin was stripped with adhesive tape. All samples (including strips, dressing and swabs) were analyzed for radioactivity. The (14)C-musk ketone was poorly absorbed from the skin during the 6-hr application since only 0.5% of the dose was excreted in urine and feces during 120 hours, and approximately 86% of the dose was recovered from the site of application. Moreover, no radioactivity was detected in any of the plasma or whole blood samples or in the skin strips. When urine samples of one of the volunteers from the study above were extracted with ethyl acetate the recovery of the radioactivity was low (about 12%). When urine samples were treated with beta-glucuronidase and extracted with ethyl acetate the recovery was about 5-fold larger, indicating that a large proportion of the metabolites of musk ketone in human urine were present as glucuronide conjugates. Extracts of beta-glucuronidase treated human urine contained a single major (unidentified) metabolite which was probably also present as a minor constituent of rat bile extract.

/HUMAN EXPOSURE STUDIES/ A maximization test was carried out with 25 healthy adult volunteers. Musk ketone was applied to the fore-arms at a concentration of 5% in petrolatum under occlusion for a total of five alternate-day 48-hour periods. Each application was preceded by a 24-hour occlusive treatment of the patch site with 5% aqueous sodium lauryl sulfate. Following a 10-day rest period, a challenge application (5% musk ketone in petrolatum) was applied to fresh sites on the scapular back of each subject under occlusion for 48 hours. The challenge site was pretreated for 1 hour with 10% aqueous sodium lauryl sulfate. Under these conditions, musk ketone failed to elicit a sensitization reaction after 48 and 72 hour.

/HUMAN EXPOSURE STUDIES/ ... 13 patients, suspected to suffer from a photoallergic contact dermatitis, were screened by means of a questionnaire and clinical tests. Dermal sensitivity to UV light was pre-tested after which nitromusks (amount and vehicle not specified) were applied on the skin under occlusive patches (two sites per substance). After 24 hours of contact the patches were removed under dim light and the skin examined for any signs of contact-dermatitis. Half of the contact sites were covered again and the other half was irradiated with ultra-violet light. All persons studied showed a photoallergic reaction to musk ambrette. In one person also a photoallergic reaction to musk ketone was observed. No reaction was seen at the non-irradiated site. The study is inconclusive as to whether this patient shows either cross-photoallergy between musk ambrette and musk ketone or that this patient shows a concomittant independent photo-allergy to two nitromusks. The study is also inconclusive as to the prevalence of the condition.

/CASE REPORTS/ /Investigators/ describe a patient with chronic actinic dermatitis whose photopatch tests revealed reactions to musk ketone and musk ambrette, both of which were found in his aftershave lotion. Minimal erythema doses of UVA and UVB were decreased. After initial unsuccessful treatment with /Psoralen plus ultraviolet light therapy (aka PUVA therapy)/ the patient was successfully treated with a combination of cyclosporine and PUVA.

For more Human Toxicity Excerpts (Complete) data for Musk ketone (11 total), please visit the HSDB record page.

Ubiquitous occurrences of synthetic nitro musks are evident in the literature. The in vivo analysis of musk xylene (MX) and musk ketone (MK)-protein adducts in trout liver has been performed by gas chromatography-mass spectrometry using selected ion monitoring (GC-SIM-MS). Biotransformation, dose-response and toxicokinetics studies of 2-amino-MX (2-AMX), 2-amino-MK (2-AMK) and 4-amino-MX (4-AMX) metabolites, covalently bound to cysteine amino acids in proteins in fish liver, formed by enzymatic nitro-reduction of MX and MK, have been described. Trout were exposed to single exposures of 0.010, 0.030, 0.10, and 0.30 mg/g MX and/or MK. Forty-two fish liver samples were collected from exposed- and control-fish subsequent to exposure intervals of 1 day, 3 days, and 7 days and were composited as per exposure schedules and times. Alkaline hydrolysis released bound metabolites from exposed liver composites that were extracted into n-hexane and then concentrated and analyzed by GC-SIM-MS. The presence of the metabolites in liver extracts was confirmed based on agreement of similar mass spectral properties and retention times with standards. In the dose-response study, the maximum adduct formation was 492.0 ng/g for 2-AMX, 505.5 ng/g for 2-AMK and 12588.5 ng/g for 4-AMX in liver at 0.03 mg/g MX and MK fish in 1 day after exposure. For toxicokinetics investigation, the highest amount of the target metabolites was found to be the same concentration as observed in the dose-response study for 1 day after exposure with 0.03 mg/g MX and MK fish and the half-lives of the metabolites were estimated to be 2-9 days based on assumption of first-order kinetics. Average recoveries exceeded 95% with a relative standard deviation (RSD) around 9%, and the limit of detection (LOD) ranged from 0.91 to 3.8 ng/g based on a signal to noise ratio of 10 (S/N=10) could be achieved for the metabolites. No metabolites were detected in the controls and exposed non-hydrolyzed liver extracts. This is the first report on dose-response and toxicokinetics of nitro musk-cysteine-protein adducts in fish liver.

Two healthy male volunteers received an application of 2.2 mg ring-labeled (14)C-musk ketone (in a mixture of phenylethyl alcohol and ethanol) on the unshaven skin of the upper left quadrant of the chest for 6 hours. The dose was applied evenly over an area of 100 sq cm. The application rate was 0.02 mg/sq cm. ... When urine samples were treated with beta-glucuronidase and extracted with ethyl acetate the recovery was about 5-fold larger, indicating that a large proportion of the metabolites of musk ketone in human urine were present as glucuronide conjugates. Extracts of beta-glucuronidase treated human urine contained a single major (unidentified) metabolite which was probably also present as a minor constituent of rat bile extract.

The absorption, distribution and excretion of radioactivity have been determined after a 6-hour topical application with 0.5 mg/kg bw of ring-labeled (14)C-musk ketone (in a mixture of phenylethyl alcohol and ethanol) to the shaven backs of 21 male rats (16 CD Sprague- Dawley and 5 Long-Evans). The dose was applied evenly over an area of 9 sq cm. The application rate was 0.01 mg/sq cm ... In CD rats and Long-Evans rats 14.6-26.3% and 13.3%, respectively, of the radiolabeled dose was absorbed from the shaven backs during 6 hours. After removal of the (14)C-musk ketone at 6 hours of application 16% of the dose remained on the skin which continued to be absorbed. This is supported by data obtained on animals killed at later times which show a steady decrease in the amount of material found on the treated skin from 7.2-9.85% of the dose at 8 hours to 3.1-4.1% after 24 hr and 2.0-3.4% after 48 hours. The actual absorption at 8 hours was approximately 19%, at 24 hours 25.1-28.3%, and at 48 hours 26.2-32.7%. After 48 hours, absorption essentially ceased while approximately 3% of the dose remained unabsorbed on the skin. In Long-Evans rats the disposition of radioactivity was similar with absorption of (14)C-musk ketone rising to 29.3-40.2% of the dose between 48 and 120 hours. The mean proportion of the dose remaining on the treated skin after 24 hours was approximately 3%.

The absorption, distribution and excretion of radioactivity have been determined after a 6-hour topical application with 0.5 mg/kg bw of ring-labeled (14)C-musk ketone (in a mixture of phenylethyl alcohol and ethanol) to the shaven backs of 21 male rats (16 CD Sprague- Dawley and 5 Long-Evans). The dose was applied evenly over an area of 9 sq cm. The application rate was 0.01 mg/sq cm ... After 6 hr application the dressing and foil were removed and the remaining dose at the treated area was wiped off ... In CD rats means of 7.3% and 17.2% of the applied dose had been excreted in the urine and feces, respectively, after 120 hours. In Long-Evans rats the rate of elimination was comparable with 10.8% and 27.2% of the dose excreted during 5 days in the urine and feces, respectively. Most radioactivity was eliminated in the first 48 hr after start of dosing. No radioactivity was detected in expired air.

The absorption, distribution and excretion of radioactivity have been determined after a 6-hour topical application with 0.5 mg/kg bw of ring-labeled (14)C-musk ketone (in a mixture of phenylethyl alcohol and ethanol) to the shaven backs of 21 male rats (16 CD Sprague- Dawley and 5 Long-Evans). The dose was applied evenly over an area of 9 sq cm. The application rate was 0.01 mg/sq cm ... After 6 hr application the dressing and foil were removed and the remaining dose at the treated area was wiped off ... In the bile duct cannulated CD rats only 1.8% of the dose was eliminated in the urine in 48 hours, while 25.3% was collected in the bile (of which 15.8% within 24 hours). The non-cannulated rat excreted 8% of the dose in the urine in 48 hours. These results indicate that the predominant route of excretion for (14)C-musk ketone is via the bile, and therefore that most of the radioactivity in the urine of cannulated animals is due to material that had been reabsorbed from the gastro-intestinal tract. In bile, at least six drug-related components were present as beta-glucuronic acid conjugates which were apparently deconjugated and further metabolized in the gastro-intestinal tract to other more polar components, some of which were at least partially reabsorbed giving rise to a complex profile of urinary metabolites. Radioactivity was detected in nearly all the tissues of animals killed at 1-120 hours after start of dose application. Concentrations were highest at about 6 hours after start of dosing in all tissues. Between 8 and 120 hr the concentration of radioactivity declined steadily in all tissues so that at 120 hours after start of dosing the concentration of radioactivity in each tissue was in general less than 20% of its peak value. Throughout the study the highest concentrations of radioactivity were found in the gastro-intestinal tract, liver, adipose tissue, adrenals, thyroid and kidneys, which at 6 hours after start of dosing contained means of 0.645 ug musk ketone equivalents/g, 0.32 ug/g, 0.19 ug/g, 0.12 ug/g, 0.10 ug/g and 0.08 ug/g, respectively, in CD rats. The distribution of radioactivity in the tissues of Long-Evans rats was similar with the highest peak concentrations of radioactivity at 6 hr after start of dosing in the gastro-intestinal tract (0.47 ug musk ketone equivalents/g), liver (0.26 ug/g), adrenals (0.1 ug/g), thyroid (0.18 ug/g) and fat (0.16 ug/g).

Ring-labeled (14)C-musk ketone (in phenylethyl alcohol and ethanol) was applied under occlusion to the shaven backs (area about 9 sq cm) of 10 male Sprague-Dawley CD rats up to fourteen daily 24-hour doses of 0.5 mg/kg bw. The skin remained unrinsed between the applications. Two rats were killed for whole-body autoradiography, one 24 hours after the first dose, and the other 24 hours after the 14th dose. From the remaining 8 rats, urine and feces were collected at several time points, and at sacrifice samples of blood, treated skin, brain, kidney, liver, thyroid, and fat were taken. Whole-body autoradiography showed that at 24 hours after the first dose radioactivity was not widely distributed throughout the body. Relatively high concentrations were present at the site of application and in the caecal contents, large intestine contents, and bile ducts. Lower levels were present in the small intestine contents and liver. Tissues of the rat killed at 24 hours after the 14th dose generally contained more radioactivity, although the highest concentrations were still associated with the site of application and the gastro-intestinal tract and lower levels were present in liver, blood, and thyroid. Hence, the absorption of radioactivity was incomplete, given the large amounts of the applied radioactivity remaining at the site of application. Means of 1.48 and 2.34 ug musk ketone equivalents were excreted in urine and feces, respectively, in the 24 hours following the application of dose 1. The mean rate of excretion in the urine increased to 6.54 ug/day during the 24 hours following the application of dose 14. The mean rate of excretion in feces increased to maxima of about 14.8 ug/day in the 24 hours following application of both dose 12 and dose 14. At sacrifice, the concentration of radioactivity in treated skin was high, whereas the total radioactivity present in blood and selected tissues was only a very small proportion of the total of 14 applied doses (0.22-0.37% in liver, and even less in fat, blood, kidneys, brain, and thyroid).

For more Absorption, Distribution and Excretion (Complete) data for Musk ketone (9 total), please visit the HSDB record page.

Musk ketone is widely used as a fixative in blossom and fantasy compositions.

Fragrance

2023: 68,143 lb

Production volumes for non-confidential chemicals reported under the Inventory Update Rule. [Table#7335]

Non-confidential 2016 Chemical Data Reporting (CDR) information on the production and use of chemicals manufactured or imported into the United States. Chemical: Ethanone, 1-[4-(1,1-dimethylethyl)-2,6-dimethyl-3 ,5-dinitrophenyl]-:

Use in fragrances in the USA amounts to approximately 50,000 lb/yr.

Usual concentration in final product (%): soap 0.03 (0.15 maximum); detergent 0.003 (0.015 maximum); creams, lotions 0.01 (0.05 maximum); perfume 0.2 (0.5 maximum)

Musk ketone

1-(4-tert-Butyl-2,6-dimethyl-3,5-dinitrophenyl) ethanone; 4'-tert-butyl-2',6'-dimethyl-3',5'-dinitroacetophenone; 3,5-Dinitro-2,6-dimethyl-4-tert-butylacetophenone; 1-[4-(1,1-Dimethylethyl)-2,6-dimethyl-3,5-dinitrophenyl]ethanone; Ethanone, 1-[4-(1,1-dimethylethyl)-2,6-dimethyl-3,5-dinitrophenyl]-

IFRA_STD_189.pdf

45

IFRA 51st Amendment - Guidance for the use of IFRA Standards

Specification: This material should be used only if it meets the criteria stated in the Standard

Fragrance Ingredients

Cosmetics -> Masking

All Other Chemical Product and Preparation Manufacturing

Ethanone, 1-[4-(1,1-dimethylethyl)-2,6-dimethyl-3,5-dinitrophenyl]-: ACTIVE

Of the few aromatic, nitrogen-containing fragrance substances, the nitro musk material musk ketone is still important commercially as an inexpensive and tenacious musk fragrance. The other artificial nitro musks, musk ambrette and musk xylene, have lost their significance on account of their toxicological and ecotoxicological properties.

In public use since the 1900s.

The Council of Europe (1974) included musk ketone in the list of artificial flavoring substances that may be temporarily added to foodstuffs without hazard to public health.