Health Hazard Summary: Toluene mainly
affects the central nervous system (the brain), causing headache,
nausea, dizziness, clumsiness, drowsiness, and other effects like
those of drunkenness. It can also cause skin rash.
HOW TO FIND OUT IF YOU ARE
WORKING WITH TOLUENE
Physical Appearance and Odor: Toluene is a clear,
colorless, flammable liquid. It has a sweet, sharp odor. Most
people, but not all, can smell toluene at levels that are not
hazardous. Toluene belongs to a large class of chemicals called
organic solvents. Alcohols, acetone, methyl ethyl ketone,
trichloroethane, and xylene are a few other examples of organic
solvents. Toluene is sometimes called "toluol,"
"methylbenzene," or "phenylmethane."
|Products That Contain Toulene
paints, varnishes, and shellacs
paint and varnish thinners
adhesives and glues
fuel system antifreezes
high-octane gasoline blends
rotogravure printing processes
Toluene is often used in the manufacturing of other products,
although it may not be found in the finished product. Toluene is
used in the production of:
Your Right To Know: Under California's Hazard
Communication Standard (Cal/OSHA regulation GISO 5194), your
employer must tell you if you are working with any hazardous
substances, including toluene, and must train you to use them
If you think you may be exposed to hazardous chemicals at work,
ask to see the Material Safety Data Sheets (MSDSs) for the products
in your work area. An MSDS lists the hazardous chemicals in a
product, describes its health and safety hazards, and gives methods
for its safe use, storage, and disposal. An MSDS should also include
information on fire and explosion hazards, chemical reactivity,
first aid, and methods for handling leaks and spills. Your employer
must have an MSDS for any workplace product that contains a
hazardous substance, and must make the MSDS available to employees
This Fact Sheet is an aid for worker training programs. It does
not take the place of a Material Safety Data Sheet.
HOW TOLUENE ENTERS AND AFFECTS
Toluene enters your body when it evaporates into the air you
breathe. Toluene can also be absorbed through your skin, especially
with lengthy skin contact.
Overexposure to toluene mainly affects the central nervous system
(the brain), causing headache, nausea, dizziness, clumsiness,
drowsiness, and other effects like those of drunkenness. Other
symptoms can also occur, as described below.
Nervous System: Toluene, like most organic solvents, can
affect your brain the same way drinking alcohol does. Drinking
alcohol within a few hours of exposure increases these effects and
makes them last longer, because the effects of alcohol and other
organic solvents on the brain add together. The symptoms of
short-term overexposure usually clear up within hours after exposure
stops. Effects occur more quickly and become more noticeable and
serious as the level and time of exposure increase. These symptoms
can increase your chances of having accidents.
The table below lists exposure levels at which various effects of
toluene are likely to appear. The table gives exposure levels in
"ppm" ("parts per million" - the number of parts
of toluene in each million parts of air).
Most experts believe that repeated, frequent overexposure to
organic solvents over months or years can have long-lasting and
possibly permanent effects on the nervous system. The symptoms of
these long-term effects include fatigue, sleeplessness, poor
coordination, difficulty in concentrating, loss of short-term
memory, and personality changes such as depression, anxiety, and
irritability. We do not know at what exposure levels these effects
occur, and the effects have not been studied in workers exposed only
Nervous Systems Effects of Toluene
of 8-Hour Average Exposure
dizziness, drowsiness, fatigue
200 ppm nausea,
weakness, poor coordination, numbness,
lack of emotional control, staggering
800 ppm severe
nervousness, muscular fatigue, insomnia
lasts for days
>10,000 ppm loss of consciousness,
Skin: Toluene, like other organic solvents, can dissolve
your skin's natural protective oils. Frequent or prolonged skin
contact can cause irritation and dermatitis (skin rash), with
dryness, redness, flaking, and cracking of the skin. Toluene
penetrates most ordinary clothing (see "Personal Protective
Equipment," page 4) and can get trapped in gloves and boots.
Such exposure can cause burns and blistering.
Eyes, Nose, and Throat: Toluene in the air can irritate
your eyes, nose, and throat. Liquid toluene splashed in the eye can
sting, and may slightly damage the surface of the eye, but the eye
usually heals within a few days.
Hearing: One study suggested that toluene, and possibly
other organic solvents, may be able to cause hearing loss.
Lungs: Exposure to toluene at high levels can irritate the
lungs, causing chest pain and shortness of breath. Extreme
overexposure (for example, in an enclosed or confined space) can
cause pulmonary edema, a potentially life-threatening condition in
which the lungs fill with fluid. However, there is no evidence that
repeated, low-level exposure has any long-term effects on the lung.
Liver and Kidneys: At very high levels of exposure - such
as might occur in an enclosed space or during a spill - toluene can
injure the liver and kidneys. This is extremely unlikely to occur
without substantial effects on the nervous system first. Generally,
such liver or kidney damage is not permanent.
Cancer: In a U.S. National Toxicology Program test, rats
and mice exposed to high levels of toluene in the air throughout
most of their lives did not show any sign of increased cancer rates.
There is no good reason to believe that toluene causes cancer.
However, toluene is often contaminated with small amounts of
benzene, which is a known cause of leukemia and other cancers. In a
workplace where toluene is used, a proper health and safety
evaluation should consider the possibility of benzene exposure.
Genetic Changes: Most studies show that toluene does not
easily damage the genes or chromosomes, although at least one study
found minor effects among workers exposed to high concentrations for
Reproductive System: Toluene's effects on the reproductive
system have not been thoroughly studied. A number of women who have
abused toluene throughout their pregnancy (by sniffing glue or
paint) have had children with birth defects and delayed development.
Toluene is on the State of California's Prop 65 list of chemicals
known to harm the developing fetus. We don't know whether normal
workplace exposure to toluene can affect pregnancy or other
reproductive function. Pregnant and nursing women should avoid
overexposure to toluene.
In a U.S. National Toxicology Program test, toluene did not
affect the sperm of male rats or mice.
AND MEDICAL EFFECTS
There are tests that can determine the amount of toluene in your
body. However, toluene is quickly eliminated from your body, so
these tests are only useful if they are done very soon after
exposure (generally at the end of a workshift), and the tests only
provide useful information about that day's exposure. Routine
testing is not recommended or required. A health care provider can
select specific tests on a case-by-case basis to evaluate effects of
chemical exposure. HESIS physicians can provide advice for such
If symptoms such as memory loss, confusion, and mood changes
occur, neuropsychological testing may be useful.
It is generally recommended that workers who are regularly
exposed to hazardous substances get a complete physical examination,
including an occupational and medical history, at the beginning of
their employment. They should also have periodic follow-up
LEGAL EXPOSURE LIMITS
California's Division of Occupational Safety and Health (Cal/OSHA)
sets and enforces standards for workplace chemical exposure. Cal/OSHA
sets Permissible Exposure Limits (PELs) for the amounts of certain
chemicals in workplace air. The PELs are intended to protect the
health of a person who is exposed every day over a working lifetime.
Cal/OSHA's PEL for toluene is 100 ppm. This is equal to 375
milligrams of toluene per cubic meter of air (375 mg/m3).
Legally, your exposure may be above 100 ppm at times, but only if it
is below the PEL at other times, so that your average
exposure for any 8-hour workshift is no more than 100 ppm.
There is also a Short Term Exposure Limit (STEL) of 150 ppm,
which must not be exceeded during any 15-minute averaging period,
and a "ceiling" limit of 500 ppm that must never be
exceeded for any period of time.
The American Conference of Governmental Industrial Hygienists has
recommended a Threshold Limit Value (TLV) of 50 ppm. Cal/OSHA will
probably adopt this more protective recommendation as a legal PEL
Cal/OSHA requires (GISO 5155(d)) that employers provide
appropriate protective clothing as necessary to prevent skin contact
When two chemicals have similar health effects (such as toluene
and other organic solvents that affect your central nervous system
or irritate your eyes, nose, and throat), there are special rules (GISO
5155(c)(1)(B)) that set lower limits on your combined exposure.
You should not rely on your sense of smell to warn you that you
are being overexposed to toluene. Most people can smell toluene when
the concentration in the air is well below the PEL (at about 3 ppm,
on average), so smelling it does not mean that you are overexposed.
Moreover, some people may not smell it even at much higher levels.
Also, your sense of smell can become dulled after being around an
odor for awhile. Measuring the amount of a substance in the air is
the only reliable way to determine the exposure level.
If you think you may be overexposed, talk to your supervisor or
your union. If any worker might be exposed to a substance at more
than the legal limit, the employer must measure the amount of the
substance in the air in the work area (Cal/OSHA regulation GISO
5155(e)). You have the legal right to see the results of
monitoring relevant to your work (GISO 3204).
You also have the right to see and copy your own medical records,
and records of your exposure to toxic substances. These records are
important in determining whether your health has been affected by
your work. Employers who have such records must keep them and make
them available to you for at least 30 years after the end of your
REDUCING YOUR EXPOSURE
Your employer is required to protect you from being exposed to
chemicals at levels above the legal limits. Cal/OSHA and Cal/OSHA
Consultation Service can help you and your employer - see the
"Resources" section below.
Substitution: The most effective way to prevent
overexposures is to use a safer chemical, if one is available.
However, the health and safety hazards of substitutes must also be
carefully considered, to make sure that they are actually safer.
Engineering Controls: When possible, employers must use
engineering control methods rather than personal protective
equipment to prevent overexposure. Engineering control methods
include installing ventilation, changing the work process, and
changing work practices. Containers and vats should be tightly
covered to prevent evaporation. Certain work processes can be
isolated, enclosed, or automated to reduce exposures.
Local exhaust ventilation systems ("hoods") are the
most effective type of ventilation control. These systems capture
contaminated air at its source before it spreads into the air you
Personal Protective Equipment: When engineering controls
cannot reduce exposures enough, a respirator must be worn and a
respiratory protection program must be developed, as described in
detail in Cal/OSHA regulations (GISO 5144). An industrial
hygienist or other trained person should be consulted to ensure that
the equipment is appropriate and is used correctly.
If frequent or prolonged skin contact with toluene cannot be
avoided, or if splashing may occur, other protective equipment such
as gloves, goggles, or faceshields should be worn. Most protective
clothing materials have very little resistance to toluene. Some of
the protective clothing materials that are most resistant to toluene
are Teflon, Silvershield, and neoprene/Viton. Even the most
resistant materials can be penetrated very quickly, so protective
clothing should be replaced often.