FOR CHINA PAINTING
Porcelain Painters International Online
by Gene Patterson
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China painting Solvents: Things You Should Know
I have read with great interest, the recent discussions about various solvents
we use in china painting. As a health professional, I am naturally concerned
about the health hazards associated with the solvents and mediums we use.
Having witnessed, first hand, several cases of toxic disease, I have
learned great respect for these substances and have recently conducted
a search of the medical literature regarding many of the solvents common
to our art. Friends, I am here to tell you the only non-toxic solvent available,
is distilled water and even that can kill you if used improperly. Almost
every product we use in china painting is hazardous to some degree. For
that matter, so is the air we breathe in our cities. But, used properly,
we can avoid the toxic effects of our products and have both beautiful
porcelains and good health.
Many of us "more mature" folks have been painting for the past
forty or fifty years and suffer no ill effects because we treat our materials
with respect. Understanding how to do that should be lesson number one
for all china painters.
Some people are simply more sensitive to certain solvents and painting
mediums, and they tend to develop headaches when exposed to those substances.
Although, I suspect many "china painter headaches" are only indirectly
caused by the solvents. More about that later.
HOW SOLVENTS HARM US
When you examine the list of solvents you will see notes of their potential
hazardous effects. It is my belief that when people have an understanding
of how a substance harms them, they are more successful in protecting themselves
against it. For that reason I am presenting a quick and simple overview
of physiological toxicology. If you think you already know this
stuff--read it anyway.
The human body is nicely designed to tolerate exposure to most toxic
substances as long as the Level of exposure is reasonably low. In fact,
the complete avoidance of toxic materials is neither possible nor desirable.
For example, many of the vitamins and minerals our bodies require, are
highly toxic in large quantities. The very oxygen we depend on for life,
becomes poisonous in high concentrations.
Several trace elements, essential for healthy cellular metabolism, are
also on the poison control list as deadly agents (e.g., selenium, chromium,
copper, iodine, potassium, etc.). The point here is to recognize which
solvents are highly toxic and learn how to limit your exposure to an amount
that does not harm you. The sensitive balance between the various chemically
transmitted signals in the brain that represent normal human behavior,
can be disrupted by foreign chemicals.
Neurotoxins are those chemicals which cause the brain
and its nervous system to malfunction. These toxic chemicals can "short
circuit" the nervous system without killing a single cell. A large number
of the solvents we use are known as aromatic hydrocarbons and
listed as central nervous system (CNS) depressants. These chemicals accumulate
in the fatty material of the nerve membranes and inhibit the impulse of
nerve signals. To the degree that this occurs, the individual is slowed
in mind and body. The symptoms can include one or more of the following:
Light headedness, headache, excitement, slurred speech, lack of coordination
(intoxication) nausea, visual disturbance, convulsions, difficulty breathing,
respiratory paralysis, unconsciousness and coma.
For china painters, it is important to evaluate such symptoms. Most
of these symptoms can also be associated with situations and conditions
not associated with toxic chemicals. In fact, most physicians do not automatically
think of toxins (except perhaps, alcohol intoxication), when the patient
presents symptoms of central nervous system disorders. If anyone develops
such symptoms following use of solvents they must tell the physician of
that exposure so that he or she can order the proper lab work to identify
or rule out a neurotoxin.
In addition to the nasty work aromatic hydrocarbons do to the
nervous system, they also accumulate in other fatty tissues such as bone
marrow, liver and kidney. In the bone marrow the chemicals can depress
the production of blood cells, causing serious anemia. The normal functions
of liver and kidney are also disrupted. The chemicals are excreted very
slowly from the body, plus they result in other metabolites such as phenol
that further damages organs. Although the mechanism is not well understood,
it is believed that chronic exposure to high Levels of organic solvents
stimulates the malignant growth of certain cancers, particularly of leukemia.
A few words are needed here to talk about headaches.
The majority of headaches are brought on by tension causing strain on muscle
tissues or blood vessels in the head, the neck, or both. There are two
common causes for headache pain. The first is strain on facial, neck and
scalp muscles usually caused by tension (tension headache). The second
common cause is swelling of blood vessels in the head area that results
in strain within the blood vessel walls (vascular headache).
If you have spent several hours concentrating on getting the design
and brush strokes just right, you are a perfect candidate for tension headache.
Also, the vapor from many of the aromatic solvents are vaso-dilators which
act to dilate (widen) blood vessels, creating a vascular headache. So,
you may not actually be allergic to, or poisoned by the solvent, just over
exposed to the solvent's vascular effects.
For someone who is genuinely allergic to a solvent, or has
kidney or liver disease, ventilation is critical.Those individuals
should consider learning to use the non-toxic mediums and solvents such
as water based mediums
RULES TO PROTECT YOURSELF
Rule #1: Adequate ventilation in your
painting area is essential. Ventilation that is adequate for using turpentine
is not necessarily adequate for using benzene. Some solvents vaporize into
the air rapidly and your goal is to dilute those fumes with fresh clean
air as quickly as possible. Otherwise, you inhale the vapor and your lungs
soak up the chemicals and transfer them to your blood stream within seconds.
My personal recommendation is that you install an exhaust fan
in the area where you paint. The type fan used in bathrooms works reasonably
well. Choose one rated for the right size of you room. Fans are rated according
to how much air they remove. This is expressed as Cubic Feet per Minute
(CFM). Choose one with a squirrel cage type fan instead of the propeller
type fan. When using large amounts of hazardous solvents, do it out
doors and limit your exposure to the concentrated vapors to short periods
of time. If you work regularly with the highly toxic chemicals, invest
in a fume mask rated for organic solvents and remember always to protect
yourself with rubber gloves and a plastic apron. The thin latex gloves
may not protect you because some solvents can diffuse through the thin
When working only with turpentine, alcohol and oil mediums, a
regular fan set to blow air out an open window will often be sufficient
to keep the amount of solvent vapor at a safe Level. Do not depend on this
arrangement to be safe when using the more hazardous solvents.
Also, keep the lids on solvent containers, removing the lid only when
using it. Another safety practice is to keep a large mouth container with
a tight lid, handy to drop in rags and tissues used to clean surfaces,
wipe brushes or spills. These cloths and tissues provide an increased surface
area for solvents to vaporize rapidly into the air. When finished painting,
take the container of solvent soaked cloths outside to dry thoroughly before
putting them into the trash or before washing them.
Do not wash these cloths with articles of clothing. >Some
of the hazardous chemicals are not soluble in water and can contaminate
your clothing then enter your body through the skin.
If you should breathe some concentrated vapors, leave the
area immediately and get into fresh air. Breathe deeply to flush your lungs
with clean air. Caution: don't hyperventilate and make yourself
Don't forget that ventilation of the area where you fire your
kiln is also important. The fumes released from burning off the
mediums, solvents and flux vapors can be quite dangerous.
The metals (primarily metallic oxides) which make up our
china paint are bound into a frit. The grinding of the fused glass-like
frit produces a fine dust which can be inhaled or ingested if the painter
is not careful. We must consider all of our colors as toxic. Virtually
all the metals which give color to our paints are toxic and all the flux
compounds are toxic to varying degrees. The china paint colors are not
only dangerous in the dry powder state, but also during the firing process.
I found a surprising number of reports in the medical literature describing
an illness known as "metal fume fever". This illness results from
breathing the fumes released from metals at high temperatures. The condition
does not resemble an intoxication, but rather an infection. A sudden chill
and rise of temperature following inhalation of the metal fumes. Many suffers
of the syndrome say the actual chill is preceded by an unusual sweetish
or metallic taste in the mouth, a feeling of dryness in the throat, cough,
a sense of lassitude and malaise, sometimes nausea. The symptoms usually
pass after several hours. Chronic exposure can produce changes in the lung,
resulting in emphysema. Therefore, adequate ventilation when firing your
kiln is a good practice.
Rule #2: Avoid getting solvents
on your skin. As you will note when reading characteristics of the various
solvents, some are known sensitizing agents and may generate an allergic
reaction in people who were not sensitive at first, to those particular
chemicals. Turpentine, for example, is a known sensitizer. Not everyone
develops allergies to the chemical, but many do.
Other solvents dissolve the fats and oils in your skin, causing
everything from dry scaly skin to irritation and infections. There are
also solvents which are readily absorbed by the skin, allowing the chemical
rapid access to your blood system where it can destroy bone marrow, depress
the central nervous system and wreck havoc with liver and kidney function.
Wear rubber gloves when working with the more dangerous solvents
and when you get solvent on you skin, wash it off immediately with
plenty of soap and water.
Finally, it is a definite NO-NO to put any solvent (except
water and low concentrations of grain alcohol) in your mouth. Most solvents
can quickly pass through the mucous membrane to enter the blood system.
Don't eat or smoke while painting and wash your hands thoroughly after
painting and before putting anything in your mouth.
Rule #3: Faithfully observe
rules #1 and #2.
We don't need to be fearful of our solvents, but learn
to respect them for what they are and what they can do. If you do not have
the proper equipment and cannot use a particular solvent safely, then avoid
PROPERTIES AND HAZARDS OF SOLVENTS
As I reviewed the medical and toxicology literature, I was surprised occasionally
to discover that some chemicals were far more dangerous than I had thought.
Other chemicals turned out to be much less hazardous than I had believed
them to be. As mentioned earlier, various solvents can greatly enhance
our ability to practice the art of china painting. It is up to us to use
those chemicals with understanding and respect for what they can do for
us and to us.
The following is a listing of the more common solvents used in
china painting. The list is not exhaustive because I have not been successful
yet in finding the critical information about some of the solvents. When
that information is available, this list will be updated to include it.
As I come across new information from the medical journals, that too will
When reading the dangers and symptoms of these solvents, keep in mind
that they can be used if treated with respect. Don't be frightened by this
information, just be instructed. If you understand it, you can use it
safely. The information appearing in parentheses beside the solvent
name, represents synonyms or other names by which the solvent is known.
Acetone (dimethyl ketone) A
colorless volatile flammable liquid Ketone.
USES: Solvent for Roman gold, other resins, oils and varnishes. Degreaser
and cleaner for glazed surface. Brush cleaner (may damage some synthetic
bristles); Additive to certain mediums.
TOXICOLOGY: Moderately toxic rating.Irritating to nose and eyes; minimal
absorption through skin;dissolves skin oils; may cause eczema.
SYMPTOMS OF OVER EXPOSURE: Inhalation of concentrated amounts over
an extended period can produce narcotic effect -- Headache, intoxication,
drowsiness, nausea and vomiting. No permanent effects reported.
Household Ammonia (ammonium hydroxide
USES: A surfactant for cleaning and degreasing glazed surfaces.
TOXICOLOGY: A severe irritant and corrosive.
SYMPTOMS OF OVER EXPOSURE: Ulceration of conjuctiva and cornea.
May produce headache, bronchitis, pulmonary edema and nausea. Damage to
eyes and lungs may be permanent.
Amyl acetate (Banana oil; Pear
oil) A colorless flammable liquid with fruity odor.
USES: Solvent for waxes; has been used in some painting mediums.
TOXICOLOGY: Can cause central nervous system depression.
SYMPTOMS OF OVER EXPOSURE:Shortness of breath, headache, dizziness.
High concentrations can damage kidney and liver. No long term permanent
Benzene (Benzol) A
colorless, volatile, highly flammable and explosive liquid Aromatic Hydrocarbon.
USES: Degreaser and cleaner; solvent for fats, waxes and oils.
TOXICOLOGY: Highly toxic rating. Absorbed through the skin
and lungs. Is metabolized in the body to a phenalic compound which can
damage bone marrow tissue, depressing the production of blood cells. It
is a central nervous system depressant and can cause liver necrosis.
SYMPTOMS OF OVEREXPOSURE: Anemia. Euphoria, excitement, headache,
dizziness, incoherent speech, confusion, convulsions, unconsciousness and
Benzine (Gasoline; Petrol) A colorless
to yellow, volatile flammable liquid. An Aliphatic Hydrocarbon
USES: Used as a solvent of asphaltum for acid etching on porcelain.
Note: Rectified Benzine contains no benzene or aromatic hydrocarbons and
is often used as substitute for turpentine.
TOXICOLOGY: Moderate toxic rating The higher the octane rating, the
more hazardous it becomes. Absorbed by inhalation and ingestion; not easily
absorbed through skin. It is an irritant to the eyes, nose and throat.
A central nervous system depressant. Severe intoxication can cause damage
to the brain, liver and kidneys.
SYMPTOMS OF OVER EXPOSURE: Conjunctivitis; choking; headache; dizziness;
mental confusion; nausea; ataxia and coma.
Denatured Alcohol Mixture of ethyl alcohol
and denaturant such as denatonium benzoate or methyl alcohol to prevent
its use for drinking purposes. A colorless flammable liquid
USES: Cleaning glazed surfaces; Cleaning brushes; A thinner for some
TOXICOLOGY: Moderate toxic rating. Absorbed by ingestion and moderate
absorption through skin. Depresses the central nervous system and can damage
the optic nerve.
SYMPTOMS OF OVER EXPOSURE: Intoxication; Confusion; Incoherent speech;
Convulsions; Coma; Blindness.
Ethyl Alcohol (Drinking alcohol; Everclear
Alcohol; Grain Alcohol) A colorless flammable liquid
USES: Used in some water based mediums, and as a cleaner for glazed
TOXICOLOGY: Moderate toxic rating. Absorbed by ingestion and moderate
absorption through the skin. Produces intoxication. Excessive exposure
results in central nervous system depression and gastritis.
SYMPTOMS OF OVER EXPOSURE: Dizziness; mental confusion; ataxia; incoherent
speech; unconsciousness; coma.
Gasoline (See entry for Benzine)
Propylene Glycol A colorless syrupy
USES: An ingredient in some water based mediums. Also used as component
TOXICOLOGY: Mild to moderate toxic rating Readily absorbed by ingestion.
Not irritating to skin or eyes and not easily absorbed through the skin.
Ingestion of large amounts can produce central nervous system depression,
and kidney or liver damage. Moderate prolonged exposures have not resulted
in chronic toxicity. Note: Ethylene Glycol is much more toxic
than propylene Glycol and has caused serious damage to the kidney. The
Glycol ethers, termed cellosolves, are more volatile and more toxic. The
cellosolves are absorbed readily through the skin, and can cause kidney
and nervous system damage as well as damage to the red blood cells.
Glycerin A colorless syrupy liquid type
USES: Used as a medium or an ingredient of some mediums.
TOXICOLOGY: Minimal toxic rating
SYMPTOMS: Can cause diarrhea when ingested.
Isopropyl Alcohol (Rubbing alcohol)
A colorless flammable liquid obtained from propylene, a petroleum product.
USES: A 91% - 95% solution is used for cleaning glazed surfaces; An
ingredient in some mediums; As a brush cleaner.
TOXICOLOGY: Moderate toxic rating if ingested. Absorbed by ingestion
or inhaling heavy concentrations of the vapor. Not easily absorbed through
skin. Metabolized to acetone in the body.
SYMPTOMS OF OVER EXPOSURE: Flushing; headache; dizziness; mental depression;
vomiting; anesthesia; coma. Toxic effects are rare in normal use.
Kerosine (Kerosene; Lamp Oil) A
colorless to pale yellow flammable liquid Aliphatic Hydrocarbon
USES: As an ingredient in mediums; A solvent for asphaltum in acid
etchng pirocess; As a brush cleaner.
TOXICOLOGY: Moderate toxic rating Aspiration or inhalation in high
vapor concentrations causes upper and lower respiratory injury;
SYMPTOMS OF OVEREXPOSURE: Headache; Drowsiness; Pulmonary hemorrhage;
Pneumonia; Coma. Toxic effects are rare in normal use.
Methyl Alcohol (Methanol; Wood Alcohol)
flammable liquid produced from distillation of wood.
USES: A cleaner and industrial use solvent; To denature ethyl alcohol.
Not recommended for china painting use.
TOXICOLOGY: Highly toxic rating The smallest alcohol molecule and easily
absorbed through skin, mucous membrane, inhalation and ingestion. It damages
the optic nerve, causing blindness. Produces central nervous system depression.
SYMPTOMS OF EXPOSURE: Intoxication; Confusion; Incoherent speech; Blindness;
Convulsions; Coma; Death.
Mineral Spirits (Paint thinner) Colorless
flammable explosive liquid Aromatic Hydrocarbon. Actual composition may
vary from one manufacturer to another, but most contain mixtures of Stoddard
solvent, Benzene, Toluene and Naphtha.
USES: Cleaner; Solvent for mediums; Brush cleaner
TOXICOLOGY: Highly toxic rating. Absorption by inhalation and
through skin. It damages bone marrow and blood cell production; Causes
central nervous system depression; Can cause lung, kidney and liver damage.
SYMPTOMS OF OVER EXPOSURE: Skin irritation; Eye, nose and throat irritation;
Pulmonary edema; Headache; Dizziness; Incoherent speech; Confusion; Convulsions;
Nitrobenzene (Nitrobenzol; Oil of Mirbane)
to yellow oily flammable explosive liquid
USES: Softener and solvent for Roman Gold and other resins; Used as
TOXICOLOGY: Highly toxic rating Readily absorbed through skin, as well
as inhalation, and is slowly metabolized in body (50% may still be present
in body after 7 days). Causes anoxia (loss of oxygen carrying capacity
of blood). Chronic exposure is associated with damage to liver, spleen,
kidney and with testicular atrophy; Is a central nervous system poison
and causes cancer in laboratory animals.
SYMPTOMS OF OVER EXPOSURE: Headache; Cyanosis (blueness of lips, nose,
earlobes and finger nail beds); Shortness of breath; Weakness; Dizziness;
High heart rate; Ringing in ears; Numbness of limbs; Vomiting; Respiratory
Toluene (Toluol; Methylbenzene; Phenylmethane)
to yellow flammable liquid Aromatic Hydrocarbon distilled from crude oil.
USES: An ingredient in most brands of paint thinner, many different
glues, and solvent for lacquers and varnishes.
TOXICOLOGY: Highly toxic rating . Causes more severe skin irritation
than does benzene, but is less well absorbed through the skin. Vapors are
irritating to respiratory tract and to the eyes; Has more severe central
nervous system effects than Benzene; Damages kidney and liver. This is
the narcotic sought by "glue sniffers" who develop kidney and liver
damage as a result of this practice.
SYMPTOMS OF OVER EXPOSURE: Skin irritation; Pulmonary edema; Euphoria;
Excitement; Dizziness; Incoherent speech; Confusion; Convulsions; Unconsciousness;
1,1,1,-trichloroethane Colorless non flammable
liquid with sweet odor. It is a Chlorinated Hydrocarbon.
USES: A non polar solvent and dispersing agent, used as a medium in
some types of raised paste and enamels,also used as dispersing agent for
TOXICOLOGY: Moderate toxic rating. Evaporates easily at room
temperatures. Exposure to this chlorinated hydrocarbon in combination with
exposure to isopropyl alcohol or ethyl alcohol, or with acetone, enhances
the toxic effects of central nervous system depression.
SYMPTOMS OF OVER EXPOSURE: Skin irritation due to removal of skin oil;
May produce transient numbness of skin; Inhalation of vapors in heavy exposure
causes pulmonary edema; Dizziness; Blurred vision; Nervousness; Nausea;
Confusion; Irregular heartbeat; Unconsciousness. Symptoms usually pass
quickly when exposure stops. Suspected of causing delayed lung, liver and
Turpentine (Turps; Spirits of turpentine;
Gum Turpentine; Gum spirits; Gum Thus) Colorless to yellow flammable
liquid distilled from certain pines.
USES: Brush cleaner; cleaner for glazed surface; medium thinner; painting
TOXICOLOGY: Slight toxic rating. It is a skin irritant and sensitizer,
producing allergic reactions in those who become sensitized to the solvent.
Heavy exposure can irritate eyes, nose and throat as well as gastric and
bladder irritation. Can produce central nervous system depression and toxic
SYMPTOMS OF OVER EXPOSURE: Conjunctivitis; Vesication and eczema of
skin; Headache; Pulmonary edema; Delirium; Dizziness; Nausea; Excessive
salivation; Fever; Chest pain; Pneumonia; Abdominal colic; Diarrhea; Blood
and albumen in urine.
- Turpenoid An odorless mineral spirits
A clear flammable liquid hydrocarbon. Manufacturer does not provide
information about component chemicals. To be safe treat this solvent
as though it contained Stoddard solvent, Toluene and Napatha.
USES: Brush cleaner and thinner for some painting mediums.
TOXICOLOGY: Medium to high toxic rating. Absorption by
inhalation, ingestion and through the skin. Can cause central nervous
system depression, eye and skin irritation, plus lung damage.
SYMPTOMS OF OVER EXPOSURE: Nausea; headache; eye irritation;
chest pain; confusion; dizziness; convulsions and coma.
- Turpenoid Natural A clear yellow, non
flammable liquid with citus odor. Composition unknown.
USES: Brush cleaner; painting medium; dispersing agent for luster.
TOXICOLOGY: No reports found in medical or toxicology literature.
OSHA file lists this solvent as non toxic with no expected health hazards.
Xylene (Xylol; Dimethylbenzene) Colorless
oily highly flammable liquid Aromatic Hydrocarbon
USES: A solvent for some gums, resins, castor and linseed oil mediums.
TOXICOLOGY: Moderate toxic rating. Absorbed by inhalation. High
vapor concentration can produce central nervous system depression and pulmonary
edema. It is not easily absorbed through skin.
SYMPTOMS OF OVER EXPOSURE: Skin irritation due to removal of skin oils;
Labored breathing; Pneumonia; Agitation; Confusion; Incoherent speech;
Now, go back and read Rule #3.