Information Regarding 2-Butanone, Paint, and Coatings
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METHYL
ETHYL KETONE
Synonym: 2 butanone
78-93-3
http://toxnet.nlm.nih.gov/cgi-bin/sis/search/f?./temp/~IBLrmF:1
Consumption Patterns :
Projected growth figure through 1983 is 4%.
Production of industrial coatings was 3.8% higher in
1978 than year before. Paint and varnish sales grew
13.6% during the same period.
Probable Routes of Human Exposure :
NIOSH (NOES Survey 1981-1983) has
statistically estimated that 1,221,857 workers (201,308 of these are female) are
potentially exposed to methyl ethyl ketone in the US(1). Occupational exposure
may be through inhalation and dermal contact with this compound at workplaces
where methyl ethyl ketone is produced or used(SRC). The 8 hour TWA exposure to
methyl ethyl ketone was 45.4 ppm in a survey of 50 occupationally exposed male
subjects working in a magnetic videotape producing factory(2). These workers had
average concns of methyl ethyl ketone of 2 ppm and 1.4 mg/l in breath and blood
samples respectively(2). The mean concn of methyl ethyl ketone in the breathing
zones of 47 US plants using polyurethane coatings was
4.33 ppm(3). Methyl ethyl ketone was detected in the breathing zones in 20 of 70
samples (mean concn 12 mg/cu m) obtained from autobody shops and spray paint
shops in Australia(4).
Synonyms :
AETHYLMETHYLKETON
(GERMAN)
**PEER REVIEWED**
Synonyms :
ETHYLMETHYLKETON
(DUTCH)
**PEER REVIEWED**
Synonyms :
METILETILCHETONE
(ITALIAN)
**PEER REVIEWED**
Synonyms :
METYLOETYLOKETON
(POLISH)
**PEER REVIEWED**
Environmental Fate/Exposure Summary :
Methyl ethyl ketone's production and use as a
solvent for coatings, resins, rubbers, plastics,
pharmaceuticals, adhesives and rubber cements will result in its release to the
environment through various waste streams. Its use as a starting material or
intermediate in the manufacture of chemical products will also lead to its
release to the environment. Methyl ethyl ketone occurs naturally as a metabolic
byproduct of plants and animals and is released into the atmosphere by volcanoes
and forest fires. Based on an experimental vapor pressure of 91 mm Hg at 25 deg
C, methyl ethyl ketone is expected to exist solely as a vapor in the ambient
atmosphere. Vapor-phase methyl ethyl ketone is degraded in the atmosphere by
reaction with photochemically-produced hydroxyl radicals with an estimated
atmospheric half-life of about 14 days. This compound is also expected to
undergo photolysis in the atmosphere by natural sunlight. Photochemical
degradation of methyl ethyl ketone by natural sunlight is expected to occur at
approximately 1/5 the rate of degradation by photochemically produced hydroxy
radicals. Methyl ethyl ketone is expected to have very high mobility in soils
based upon measured Koc values of 29 and 34 obtained in silt loams.
Volatilization from dry soil surfaces is expected based upon the vapor pressure
of this compound. Volatilization from moist soil surfaces is also expected based
upon the measured Henry's Law constant of 4.7X10-5 atm-cu m/mol. The
volatilization half-life of methyl ethyl ketone from silt and sandy loams was
measured as 4.9 days. This compound is expected to biodegrade under aerobic and
anaerobic conditions. In water, methyl ethyl ketone is not expected to adsorb to
suspended solids or sediment based upon its measured Koc values. Volatilization
from water surfaces is expected to be an important environmental fate process
given its Henry's Law constant. Estimated half-lives for a model river and model
lake are 19 and 197 hours, respectively. Bioconcentration in aquatic organisms
is considered low based upon an estimated BCF value of 1. Occupational exposure
may be through inhalation and dermal contact with this compound at workplaces
where methyl ethyl ketone is produced or used. The general population may be
exposed to methyl ethyl ketone through the use of commercially available
products containing this compound such as paints,
adhesives, and rubber cements. Exposure will also arise from inhalation of
ambient air and ingestion of drinking water and food that contains methyl ethyl
ketone. (SRC)
Consumption Patterns :
SOLVENT FOR VINYL COATINGS,
30%; SOLVENT FOR ADHESIVES, 18%; SOLVENT FOR NITROCELLULOSE COATINGS,
13%; SOLVENT FOR ACRYLIC COATINGS, 11%; SOLVENT FOR
OTHER COATINGS, 7%; SOLVENT FOR MAGNETIC TAPES, 7%;
EXTRACTION SOLVENT FOR LUBE OIL DEWAXING, 5%; SOLVENT FOR PRINTING INKS, 5%;
OTHER, 4% (1981)
Biological Half-Life :
Both animal and human data indicate a rapid
turnover of MEK. In guinea-pigs receiving an ip dose of 450 mg MEK/kg, the
half-life of MEK in blood serum was 4.5 hr and the clearance time for MEK in
serum was 12 hr. For the metabolites 2-butanol, 3-hydroxy-2-butanone
and 2,3-butanediol, the clearance time in serum was 11 hr ... In a study
... on rats given an oral dose of 2-butanone of 2.1
mg/kg, there was a half-life of 3.6 hr for MEK in blood if the rate of loss was
assumed to be constant between the two times of measurement (4 and 18 hrs) after
dosing. Data from a study ... on rats receiving oral doses of 2-butanol or MEK
also indicate a half-life of about 4 hr for MEK. ... the clearance rate for
3-hydroxy-2-butanone and 2,3-butanediol was independent
of dose for the two doses used (0.4 and 0.8 g/kg) and that the half-lives for
these metabolites of MEK were 47 min and 3.45 hr, respectively.
Absorption, Distribution & Excretion :
Relatively little of absorbed MEK is excreted
unchanged via the kidneys; a study of occupationally exposed workers revealed
that it is less than 0.1% of the alveolar uptake ... In a similar study of
workers occupationally exposed to a mixture of solvents, the excretion of MEK
and a major recognizable metabolite, 3-hydroxy-2-butanone, was
0.1% of alveolar uptake ... The concentrations of both MEK and 3-hydroxy-2-butanone
in urine were significantly correlated with the environmental level of
MEK. Other metabolites of MEK, 2-butanol or 2,3-butanediol ... identified in the
serum of guinea pigs, were not detected in the urine of the exposed workers. ...
however ... human excretion of 2,3-butanediol was individually variable but
averaged 2% of the absorbed MEK. The urinary excretion of 2-butanol, a minor
metabolite of MEK was examined ... clearance of 2-butanol admin by gavage in
rabbits was about 14% of the admin dose and in the form of a glucuronide.
Major Uses :
AS SOLVENT; IN THE SURFACE COATING
INDUSTRY; MFR OF COLORLESS SYNTHETIC RESINS, SMOKELESS POWDER
Major Uses :
IN FABRIC COATING; IN
ARTIFICIAL LEATHER MFR; IN LACQUER & VARNISH INDUSTRY; IN PHARMACEUTICALS
& COSMETICS; IN SYNTHETIC RUBBER MFR; IN PRODUCTION OF LUBRICATING OILS
Major Uses :
PAINT REMOVERS;
CEMENTS & ADHESIVES; ORG SYNTHESIS; IN CLEANING FLUIDS
Major Uses :
SOLVENT FOR COATINGS-ESP
VINYL, NITROCELLULOSE & ACRYLIC
Consumption Patterns :
CHEMICAL PROFILE: Methyl Ethyl Ketone. Coatings
solvent, 50%; adhesives, 13%; magnetic tapes, 8%; lube oil dewaxing, 4%;
printing inks, 3%; miscellaneous, 6%; exports, 16%.
Human Toxicity Excerpts :
METHYL ETHYL KETONE IS IMPLICATED AS THE CAUSE
OF RETROBULBAR NEURITIS IN PT WHO USED THE SOLVENT IN REMOVING PAINT
FROM AN AIRPLANE HANGAR.
Human Toxicity Excerpts :
To determine whether unchanged solvent urinary
concentration could be used as a biological exposure index, workers
occupationally exposed to various solvents were studied. Nine unrelated groups
(a total of 659 males) working in plastic boat, chemical, plastic button, paint,
and shoe factories were studied. Urine samples were collected at the beginning
of the workshift and at the end of the first half of the shift. A close
relationship (correlation coefficient always above 0.85) between the average
environmental solvent concentration (mg/cu m) measured in the breathing zone and
the urinary concentration of unchanged solvent (ug/l) was observed.
Human Toxicity Excerpts :
A case of retrobulbar neuritis in a sailor who
was using large quantities of MEK as a paint remover
was reported. The affected individual complained of blurred vision,
light-headedness, and nausea after being exposed to MEK vapor for 1.5 hr. Upon
admission to a military hospital, the patient's near- and far-field visual
acuity was reduced and blind spots were markedly enlarged when a white target
was viewed. An ophthalmoscopic examination, however, did not reveal any
abnormalities. Clinical testing on the day of admission revealed elevations in
blood methanol and formaldehyde. Visual acuity returned to normal within 2 days
of admission; however, the blood methanol levels did not return to normal until
the sixth day of hospitalization. /It was/ concluded that MEK was the causative
agent for the optic nerve damage that was observed. The MEK was assumed to have
been systemically absorbed both dermally and through the lungs and then
partially metabolized to methanol, which subsequently affected the optic nerve
and cerebral cortex.
Human Toxicity Excerpts :
A case of toxic encephalopathy with dementia
and cerebellar ataxia in a 38-year-old male who spray-painted a truck in an
unventilated garage with a paint that contained
toluene, MEK, and propylene glycol. As time passed following the exposure, the
individual began to experience memory problems along with headaches, shortness
of breath, appetite and sleep disturbances, ataxia, and suicidal depression.
Neuropsychological evaluations over a 2.5 year period revealed distinct
cognitive, motor, and behavioral changes.
Artificial Pollution Sources :
Methyl ethyl ketone's production and use as a
solvent for coatings, resins, rubbers, plastics,
pharmaceuticals, adhesives and rubber cements(1-3) will result in its release to
the environment through various waste streams(SRC). Its use as a starting
material or intermediate in the manufacture of chemical products(2,3) will also
lead to its release to the environment(SRC).
Probable Routes of Human Exposure :
The general population may be exposed to
methyl ethyl ketone through the use of commercially available products
containing this compound such as paints, adhesives, and
rubber cements(SRC). Exposure will also arise from inhalation of ambient air,
ingestion of drinking water and food that contains methyl ethyl ketone(SRC). The
average blood concn of methyl ethyl ketone in 600 non-occupationally exposed
individuals in the US was 7.1 ppb(1).
Synonyms :
2-BUTANONE
**PEER REVIEWED**
Non-Human Toxicity Excerpts :
ANALYSIS OF PORPHYRIN CONTENT OF MURINE
ERYTHROLEUKEMIA (MEL) CELLS INCUBATED WITH 2-BUTANONE SHOWED
THAT INCR HEMOGLOBIN SYNTH WAS ACCOMPANIED BY ACCUM OF PORPHYRINS.
Metabolism/Metabolites :
GUINEA PIGS WERE GIVEN SINGLE 450 MG/KG IP
DOSES OF METHYL ETHYL KETONE (MEK). MEK PRODUCED 2-BUTANOL, 3-HYDROXY-2-BUTANONE,
& 2,3-BUTANEDIOL.
Metabolism/Metabolites :
Rats were given a single oral dose of methyl
ethyl ketone (MEK). The blood concn of MEK and metabolites 4 hr after dosing
were: MEK (94.1 mg/100 ml); 2-butanol (3.2 mg/100 ml); 3-hydroxy-2-butanol (2.4
mg/100 ml) and 2,3-butanediol (8.6 mg/100 ml). Blood concn of the parent
compound and metabolites 18 hr after dosing with MEK were: MEK (6.2 mg/100 ml);
2-butanol (0.6 mg/100 ml); 3-hydroxy-2-butanone (1.4
mg/100 ml); and 2,3-butanediol (25.6 mg/100 ml).
Metabolism/Metabolites :
... the toxic effects of MEK and 2-butanol
were essentially identical in rats, and that 2-butanol was rapidly oxidized to
MEK. ... identified the metabolites of MEK in guinea pigs as 2-butanol,
3-hydroxy-2-butanone and 2,3-butanediol. They
hypothesized that the metabolism followed both oxidative and reductive pathways,
with the latter leading to the production of 2-butanol.
RCRA Requirements :
U159; As stipulated in 40 CFR 261.33, when 2-butanone,
as a commercial chemical product or manufacturing chemical intermediate
or an off-specification commercial chemical product or a manufacturing chemical
intermediate, becomes a waste, it must be managed according to Federal and/or
State hazardous waste regulations. Also defined as a hazardous waste is any
residue, contaminated soil, water, or other debris resulting from the cleanup of
a spill, into water or on dry land, of this waste. Generators of small
quantities of this waste may qualify for partial exclusion from hazardous waste
regulations (40 CFR 261.5).
Sampling Procedures :
ANALYTE: 2-BUTANONE; MATRIX:
AIR; RANGE: 380-1240 MG/CU M; PROCEDURE: ADSORPTION ON CHARCOAL, DESORPTION WITH
CARBON DISULFIDE, GC.
Clinical Laboratory Methods :
A method is described for the determination of
the concn of methyl ethyl ketone and its metabolites: 2-butanol, 3-hydroxy-2-butanone,
and the meso- and d,l-isomers of 2,3-butanediol in urine. The analytes
were isolated from urine by solid-phase extraction and analyzed by capillary gas
chromatography. The recovery rates were 50-70% for the 2,3-butanediol isomers
and 88-96% for the other analytes. The precision of the method ranged 5-12%
(standard deviation %). The detection limit was 1.0 and 1.4 mg/l for meso- and
d,l 2,3-butanediol, respectively, and ranged 0.1-0.15 mg/l for the other
analytes.
Special Reports :
DHHS/ATSDR; Toxicological Profile for 2-Butanone
(1992) ATSDR/TP-91/08
GLCC
RELATED TOXIC SUBSTANCES FOUND IN THE CAMP POND AND CAMP WATER WELL 2003 AND
2004