Medical Management Guidelines for Benzene
(C
6H
6)
CAS# 71-43-2
UN# 1114
PDF Versionpdf icon[92 KB]
Synonyms include benzol, coal tar naphtha, phenyl hydride, and cyclohexatriene.
- Persons exposed only to benzene vapor do not pose substantial risks of secondary contamination to others. Persons whose clothing or skin is contaminated with liquid benzene can cause secondary contamination by direct contact or through off-gassing vapor.
- Benzene is a highly volatile, flammable liquid. Its vapor is heavier than air and may accumulate in low-lying areas. Benzene's sweet aromatic odor generally provides adequate warning of hazardous concentrations for acute exposure.
- Benzene is absorbed rapidly and extensively after inhalation and ingestion. It is absorbed less extensively through intact skin; however, percutaneous absorption may contribute to total body burden.
General Information
Description
At room temperature, benzene is a clear, colorless-to-light yellow liquid that is highly flammable. Because it is volatile, it can spread to a distant source of ignition. Benzene has a sweet aromatic odor. It is only slightly soluble in water but readily soluble with most organic solvents. Benzene is less dense than water and will float on the surface of water.
Routes of Exposure
Inhalation
Most exposures to benzene occur by inhalation. Its odor threshold generally provides adequate warning of acutely hazardous concentrations (odor threshold 1.5-5 ppm). Benzene vapor is heavier than air and may cause asphyxiation in enclosed, poorly ventilated, or low-lying areas.
Children exposed to the same levels
of benzene vapor as adults may receive larger dose because they have greater lung surface area:body weight ratios and increased minute volumes:weight ratios. In addition, they may be exposed to higher levels than adults in the same location because of their short stature and the higher levels of benzene vapor found nearer to the ground.
Skin/Eye Contact
Benzene splashed in the eyes can result in pain and corneal injury. Repeated or prolonged skin contact with liquid benzene can degrease the skin, causing it to crack and peel. Percutaneous absorption is slow through intact skin; however, benzene absorbed through the skin may contribute to systemic toxicity.
Children are more vulnerable to toxicants absorbed through the skin because of their larger surface area:weight ratio.
Ingestion
Acute toxic effects can result from ingestion of benzene. A burning sensation of the oral mucous membranes, esophagus, and stomach may occur after ingestion. Nausea, vomiting, and abdominal pain may also result from oral ingestion.
Sources/Uses
Benzene is the 17th most abundantly produced chemical in the United States. It is obtained primarily from crude petroleum. Benzene is used mainly as a raw material for synthesizing chemicals such as styrene, phenol, and cyclohexane and for manufacturing dyes, detergents, explosives, rubber, plastics, and pharmaceuticals. It is found in trace amounts in cigarette smoke and drinking water, as a contaminant in some industrial solvents, and as a constituent of motor fuels, unleaded gasoline in particular.
Standards and Guidelines
OSHA PEL (permissible exposure limit)
= 1 ppm (averaged over an 8-hour workshift).
OSHA STEL (short-term exposure limit)
= 5 ppm (15-minute sample).
NIOSH IDLH (immediately dangerous to
life or health) = 500 ppm.
AIHA ERPG-2 (maximum airborne concentration
below which it is believed that nearly all persons could be
exposed for up to 1 hour without experiencing or developing
irreversible or other serious health effects or symptoms that
could impair their abilities to take protective action) =
150 ppm.
Physical Properties
Description: Clear, colorless-to-light-yellow
liquid
Warning properties: Sweet solvent
odor at 1.5 to 5 ppm. Adequate warning for acute exposure;
inadequate for chronic exposure as olfactory fatigue can occur.
Molecular weight: 78.1 daltons
Boiling point (760 mm Hg): 176 °F
(80.1 °C)
Freezing point: 41.9 °F (5.5 °C)
Specific gravity: 0.88 (water
= 1)
Vapor pressure: 75 mm Hg at 68 °F
(20 °C)
Gas density: 2.8 (air = 1)
Water solubility: Slightly water
soluble (0.07% at 68 °F) (20 °C)
Flammability: Flammable at temperatures
~12 °F (-11 °C)
Flammable range: 1.2 to 7.8% (concentration
in air).
Incompatibilities
Benzene reacts explosively with strong
oxidizers, such as perchlorates and nitric acid, and many
fluorides.
Health Effects
- Benzene is mildly irritating to the skin, eyes, and respiratory
tract.
- Benzene may cause central nervous system depression and
arrhythmias to persons acutely exposed. Longer-term exposure
to benzene may cause anemia, alterations to the immune system,
and leukemia.
Acute Exposure
The effects of acute exposure to high
concentrations of benzene (neurological, dermal, respiratory,
gastrointestinal) can be evident immediately after exposure.
Neurological effects appear to be due primarily to the direct
effects of benzene on the central nervous system. The anesthetic
action of benzene on the central nervous system is similar
to that of other anesthetic gases, first inducing excitation
followed by depression, and if exposure continues, death through
respiratory failure. Dermal, respiratory, and gastrointestinal
effects are due to benzene's irritative properties.
Benzene is metabolized by the liver and
its metabolites are excreted by the kidney. Benzene toxicity
in large part is due to generation of oxygen radicals via
cytochrome P450. Benzene's water soluble metabolites which
are formed in the liver are responsible for its hematopoietic
effects. Benzene can cause death in acute exposure primarily
by its anesthetic properties (respiratory arrest) or its myocardial
sensitizing properties (fatal arrhythmias).
Children do not always respond to chemicals
in the same way that adults do. In addition, children of different
ages ( e.g., in utero, infants, toddlers, older children)
may have different responses to certain chemical exposures,
and thus, different protocols for managing their care may
be needed.
CNS
Generally, symptoms of CNS toxicity are
apparent immediately after inhalation of high concentrations
of benzene (3,000 ppm for 5 minutes), and 30 to 60 minutes
after ingestion. Mild effects include headache, lightheadedness,
dizziness, confusion, nausea, impaired gait, and blurred vision.
More severe effects include tremors, respiratory depression,
confusion, loss of consciousness, coma, and death. Unconsciousness
may be prolonged, although most victims regain consciousness
rapidly after they are removed from exposure.
Respiratory
Acute exposure to benzene vapor may irritate
the mucous membranes of the respiratory tract. With massive
exposure (20,000 ppm for 5 minutes), accumulation of fluid
in the lungs and respiratory arrest may ensue. Pulmonary aspiration
of toxic vomitus or ingested liquid benzene may cause severe
hemorrhagic inflammation of the lungs.
Cardiovascular
Exposure to very high concentrations
(more than 1,000 ppm) of benzene may lower the threshold of
the heart muscle to the effects of epinephrine, resulting
in life threatening arrhythmias such as ventricular fibrillation.
These effects are usually reversible if exposure is terminated.
Dermal
Benzene can cause skin irritation and
because it is a lipid solvent it degreases the skin, particularly
after prolonged or repeated contact with the liquid. Locally,
benzene can produce erythema, a burning sensation, and in
more severe cases, edema and even blistering.
Because of their larger surface area:body
weight ratio, children are more vulnerable than adults to
toxicants absorbed through the skin.
Gastrointestinal
If swallowed, benzene can irritate the
stomach, causing nausea, vomiting, and diarrhea. The estimated
lethal oral dose is 100 mL (about 1 g/kg, for a 75 kg man),
although as little as 15 mL or 50 mg/kg has caused death.
Ocular
High concentrations of benzene vapor
can cause eye irritation and visual blurring. When splashed
in the eyes, benzene may cause burning pain and sloughing
of the eye surface.
Potential Sequelae
Recovery from moderate exposure to benzene
may take 1 to 4 weeks. During this time, patients may continue
to experience impaired gait, nervous irritability, and breathlessness
for 2 weeks. Cardiac distress and yellow coloration of the
skin may persist for up to a month.
Chronic Exposure
Repeated exposure to high levels of benzene
(200 ppm) can result in persistent CNS effects. Chronic
benzene exposure in the workplace has been associated with
hematologic disorders (i.e., thrombocytopenia, aplastic anemia,
pancytopenia, and acute myelgenous leukemia). Chronic exposure
may be more serious for children because of their potential
longer latency period.
Carcinogenicity
The Department of Health and Human Services
has determined that benzene is a known human carcinogen. Hematologic
neoplasms such as acute myelogenous leukemia have been documented
to occur with chronic exposures as low as 10 ppm benzene.
Other neoplasms have been documented in animal models.
Reproductive and Developmental Effects
Benzene is not included in Reproductive
and Developmental Toxicants, a 1991 report published by
the U.S. General Accounting Office (GAO) that lists 30 chemicals
of concern because of widely acknowledged reproductive and
developmental consequences. However, it has been shown to
cross the placenta in humans and to be fetotoxic in animals.
No information was located as to the presence of benzene in
breast milk or of the potential transfer to nursing infants.
Benzene has very weak genotoxicity, Nonetheless,
special consideration regarding the exposure of pregnant women
is warranted. Medical counseling is recommended for the acutely
exposed pregnant woman.
Prehospital Management
- Victims exposed only to benzene vapor do not pose significant
risks of secondary contamination to rescuers outside the
Hot Zone. Victims whose clothing or skin is contaminated
with liquid benzene can secondarily contaminate response
personnel by direct contact or through off-gassing vapor.
- Benzene may cause central nervous system depression, cardiac
arrhythmias, cutaneous burns and respiratory irritation.
- There is no specific antidote for benzene. Treatment consists
of support of respiratory and cardiovascular functions.
Hot Zone
Rescuers should be trained and appropriately
attired before entering the Hot Zone. If the proper equipment
is not available, or if rescuers have not been trained in
its use, assistance should be obtained from a local or regional
HAZMAT team or other properly equipped response organization.
Rescuer Protection
Benzene vapor is absorbed well by inhalation
and is a mild respiratory-tract irritant. The liquid is a
mild skin irritant with slow skin absorption.
Respiratory Protection: Positive-pressure,
self-contained breathing apparatus (SCBA) is recommended in
response situations that involve exposure to potentially unsafe
levels of benzene vapor (i.e., greater than 300 ppm for 1
hour).
Skin Protection: Chemical-protective
clothing is not generally required when only vapor exposure
is expected because benzene vapor is neither irritating nor
absorbed well through the skin. Chemical-protective clothing
is recommended when contact with liquid benzene is anticipated
because skin irritation and dermal absorption occur.
ABC Reminders
Quickly access for a patent airway, ensure
adequate respiration and pulse. If trauma is suspected, maintain
cervical immobilization manually and apply a cervical collar
and a backboard when feasible.
Victim Removal
If victims can walk, lead them out of
the Hot Zone to the Decontamination Zone. Victims who are
unable to walk may be removed on backboards or gurneys; if
these are not available, carefully carry or drag victims to
safety.
Consider appropriate management of chemically-contaminated
children, such as measures to reduce separation anxiety if
a child is separated from a parent or other adult.
Decontamination Zone
Victims exposed only to benzene vapor
who have no skin or eye irritation do not need decontamination.
They may be transferred immediately to the Support Zone. All
others require decontamination as described below.
Rescuer Protection
If exposure levels are determined to
be safe, decontamination may be conducted by personnel wearing
a lower level of protection than that worn in the Hot Zone
(described above).
ABC Reminders
Quickly access for a patent airway, ensure
adequate respiration and pulse. Stabilize the cervical spine
with a collar and a backboard if trauma is suspected. Administer
supplemental oxygen as required. Assist ventilation with a
bag-valve-mask device if necessary.
Basic Decontamination
Victims who are able and cooperative
may assist with their own decontamination. Remove and double-bag
contaminated clothing and personal belongings. Leather absorbs
benzene; items such as leather shoes, gloves, and belts may
require disposal by incineration.
Flush liquid-exposed skin and hair with
plain water for 2 to 3 minutes, then wash with mild soap.
Rinse thoroughly with water.
Flush exposed or irritated eyes with
plain water or saline for at least 15 minutes or until pain
resolves. Remove contact lenses if easily removable without
additional trauma to the eye.
In case of ingestion, do not induce
emesis. Administer a slurry of activated charcoal if the
victim is alert and is able to swallow (at 1 gm/kg, usual
adult dose 60-90 g, child dose 25-50 g).
If patient exhibits seizures, administer
a benzodiazaepine; Diazepam (adult: 5 to 10 mg i.v., repeat
every 10 to 15 minutes as needed; child: 0.2 to 0.5 mg/kg
i.v., repeat every 5 minutes as needed) or Lorazepam (adult:
4 to 8 mg i.v.; child: 0.05 to 0.1 mg/kg i.v.). Consider phenobarbital
and/or phenytoin or fosphenytoin if seizures are uncontrollable
or recur after diazepam 30 mg (adults) or 10 mg (children
>5 years).
Consider appropriate management of chemically
contaminated children at the exposure site. Also, provide
reassurance to the child during decontamination, especially
if separation from a parent occurs. If possible, seek assistance
from a child separation expert.
Transfer to Support Zone
As soon as basic decontamination is complete,
move the victim to the Support Zone.
Support Zone
Be certain that victims have been decontaminated
properly (see Decontamination Zone above). Persons who have
undergone decontamination or have been exposed only to vapor
pose no serious risks of secondary contamination. Support
Zone personnel require no specialized protective gear in such
cases.
ABC Reminders
Quickly access for a patent airway. If
trauma is suspected, maintain cervical immobilization manually
and apply a cervical collar and a backboard when feasible.
Ensure adequate respiration and pulse. Administer supplemental
oxygen as required. Establish intravenous access if necessary.
Place on a cardiac monitor.
Additional Decontamination
Continue irrigating exposed skin and
eyes, as appropriate.
In cases of ingestion, do not induce
emesis. If activated charcoal has not been given previously,
administer a slurry (at 1 gm/kg, usual adult dose 60-90 g,
child dose 25-50 g) if the patient is alert and able to swallow.
Advanced Treatment
Monitor for arrhythmia, hypotension,
respiratory depression, and hypoxia. Evaluate for hypoglycemia
and electrolyte disturbances.
Patients who are comatose or have cardiac
arrhythmias should be treated according to ALS protocols.
In cases of respiratory compromise secure
airway and respiration via endotracheal intubation. If not
possible, perform cricothyroidotomy if equipped and trained
to do so.
Use extreme caution when treating patients
who have bronchospasm with aerosolized bronchodilators. The
use of bronchial sensitizing agents in situations of multiple
chemical exposures may pose additional risks. Consider the
health of the myocardium before choosing which type of bronchodilator
should be administered. Cardiac sensitizing agents may be
appropriate; however, the use of cardiac sensitizing agents
after exposure to certain chemicals may pose enhanced risk
of cardiac arrhythmias (especially in the elderly). Wherever
possible avoid the use of sympathomimetics in benzene exposed
patients. Try to avoid administering epinephrine due to the
possible myocardial sensitizing effect of benzene.
If massive exposure is suspected or
if the patient is hypotensive, intravenous saline or lactated
Ringer's solution should be infused. For adults, bolus 1,000
mL/hour intravenous saline or lactated Ringer's solution if
blood pressure is under 80 mm Hg; if systolic pressure is
over 90 mm Hg, an infusion rate of 150 to 200 mL/hour is sufficient.
For children with compromised perfusion administer a 20 mL/kg
bolus of normal saline over 10 to 20 minutes, then infuse
at 2 to 3 mL/kg/hour.
Transport to Medical Facility
Only decontaminated patients or patients
not requiring decontamination should be transported to a medical
facility. "Body bags" can increase exposure and
are not recommended.
Report to the base station and the receiving
medical facility the condition of the patient, treatment given,
and estimated time of arrival at the medical facility.
If benzene has been ingested, prepare
the ambulance in case the victim vomits toxic material. Have
ready several towels and open plastic bags to quickly clean
up and isolate vomitus. Take measures to avoid pulmonary aspiration,
i.e., place patient in lateral position.
Multi-Casualty Triage
Consult with the base station physician
or the regional poison control center for advice regarding
triage of multiple victims.
Patients who have histories or evidence
of substantial exposure and all persons who have ingested
benzene should be transported to a medical facility for evaluation.
Patients who have histories of cardiac dysrhythmias or other
heart conditions are at special risk. These patients should
also be transported for evaluation.
Patients who have inhalation exposure
who did not experience alteration of consciousness (e.g.,
confusion, syncope, unconsciousness) are not likely to have
had a significant exposure. After their names, addresses,
and telephone numbers are recorded, these patients may be
released from the scene with instructions to rest and to seek
medical care promptly if symptoms develop (see Patient
Information Sheet below).
Emergency Department Management
- Hospital personnel can be secondarily exposed by direct
contact or by vapor off-gassing from heavily contaminated
clothing or skin. Patients do not pose contamination risks
after clothing is removed and the skin is washed. Toxic
vomitus from patients who have ingested benzene may off-gas
benzene vapor.
- Benzene may cause central nervous system depression, cardiac
dysrhythmias, cutaneous burns, and respiratory irritation.
- There is no specific antidote for benzene. Treatment consists
of supportive measures.
Decontamination Area
Previously decontaminated patients and
patients exposed only to benzene vapor who have no skin or
eye irritation may be transferred immediately to the Critical
Care Area. Other patients will require decontamination as
described below.
Be aware that use of protective equipment
by the provider may cause fear in children, resulting in decreased
compliance with further management efforts.
Because of their relatively larger surface
area:weight ratio, children are more vulnerable to toxicants
absorbed through the skin. Also, emergency room personnel
should examine children's mouths because of the frequency
of hand-to-mouth activity among children.
ABC Reminders
Evaluate and support airway, breathing,
and circulation. Children may be more vulnerable to corrosive
agents than adults because of the smaller diameter of their
airways. In cases of respiratory compromise secure airway
and respiration via endotracheal intubation. If not possible,
perform cricothyroidotomy if equipped and trained to do so.
Use extreme caution when treating patients
who have bronchospasm with aerosolized bronchodilators. The
use of bronchial sensitizing agents in situations of multiple
chemical exposures may pose additional risks. Consider the
health of the myocardium before choosing which type of bronchodilator
should be administered. Cardiac sensitizing agents may be
appropriate; however, the use of cardiac sensitizing agents
after exposure to certain chemicals may pose enhanced risk
of cardiac arrhythmias (especially in the elderly). Wherever
possible avoid the use of sympathomimetics in benzene exposed
patients. Try to avoid administering epinephrine due to the
possible myocardial sensitizing effect of benzene.
Patients who are hypotensive or have
seizures should be treated in the conventional manner.
In the patient who has suffered from
seizures, coma, or cardiac arrhythmia evaluate for acidosis
and treat appropriately by administering intravenously sodium
bicarbonate (initial adult dose = 1 ampule; pediatric dose
= 1 Eq/kg). Further bicarbonate therapy should be guided by
arterial blood gas measurements.
Basic Decontamination
Patients who are able and cooperative
may assist with their own decontamination. If the patient's
clothing is wet with benzene, remove and double-bag the contaminated
clothing and personal belongings.
Flush exposed skin with soap and water
for 2 to 5 minutes (preferably under a shower). Rinse thoroughly
with water.
Irrigate irritated eyes with copious
amounts of tepid water for at least 15 minutes or until pain
resolves. Remove contact lenses if present and if removable
without additional trauma to the eye.
In cases of ingestion, do not induce
emesis. (More information is provided in Ingestion Exposure
under Critical Care Area below.) If not already done,
administer a slurry of activated charcoal (at 1 gm/kg, usual
adult dose 60-90 g, usual child dose 25-50 g). A soda can
and a straw may be of assistance when offering charcoal to
a child.
Critical Care Area
Be certain that appropriate decontamination
has been carried out (see Decontamination Area above).
ABC Reminders
Evaluate and support airway, breathing,
and circulation as in ABC Reminders above. Children may be
more vulnerable to corrosive agents than adults because of
the smaller diameter of their airways. Establish intravenous
access in seriously ill patients. Continuously monitor cardiac
rhythm. Take measures to minimize patient excitation, excessive
catecholamine release can induce life threatening arrhythmia
due to benzene's sensitizing effect on the myocardium.
Patients who are comatose, hypotensive,
or have seizures or cardiac arrhythmia should be treated in
the conventional manner.
Inhalation Exposure
Administer supplemental oxygen by mask
to patients who have respiratory symptoms. Use extreme caution
when treating patients who have bronchospasm with aerosolized
bronchodilators. The use of bronchial sensitizing agents in
situations of multiple chemical exposures may pose additional
risks. Consider the health of the myocardium before choosing
which type of bronchodilator should be administered. Cardiac
sensitizing agents may be appropriate; however, the use of
cardiac sensitizing agents after exposure to certain chemicals
may pose enhanced risk of cardiac arrhythmias (especially
in the elderly). Wherever possible avoid the use of sympathomimetics
in benzene exposed patients. Try to avoid administering epinephrine
due to the possible myocardial sensitizing effect of benzene.
Skin Exposure
If the skin was in prolonged contact
with liquid benzene, irritation may result; treat as thermal
burns.
Because of their larger surface area:weight
ratio, children are more vulnerable to toxicants absorbed
through the skin.
Eye Exposure
Continue irrigation for at least 15 minutes.
If eye irritation or injury is evident, test visual acuity.
Examine the eyes for corneal damage and treat appropriately.
Immediately consult an ophthalmologist for patients who have
severe corneal injuries.
Ingestion Exposure
Do not induce emesis.
Consider gastric lavage with a small
nasogastric tube if: (1) a large dose has been ingested; (2)
the patient's condition is evaluated within 30 minutes; (3)
the patient has oral lesions or persistent esophageal discomfort;
and (4) the lavage can be administered within 1 hour of ingestion.
Care must be taken when placing the gastric tube because blind
gastric-tube placement may further injure the chemically damaged
esophagus or stomach.
If the patient is alert, administer a
slurry of activated charcoal if not done previously (at 1
gm/kg, usual adult dose 60-90 g, child dose 25-50 g). A soda
can and straw may be of assistance when offering charcoal
to a child. When small amounts of benzene have been ingested,
activated charcoal may be administered orally without emptying
the gut.
Consider endoscopy to evaluate the extent
of gastrointestinal tract injury. Extreme throat swelling
may require endotracheal intubation or cricothyroidotomy.
Gastric lavage is useful in certain circumstances to remove
caustic material and prepare for endoscopic examination.
Because children do not ingest large
amounts of corrosive materials, and because the risk of perforation
from NG intubation, lavage is discouraged in children unless
intubation is performed under endoscopic guidance.
Antidotes and Other Treatments
There is no antidote for benzene. Hemodialysis
and hemoperfusion are not effective.
Laboratory Tests
The diagnosis of acute benzene toxicity
is primarily clinical, based on effects on neurological signs
and symptoms and respiratory effects. However, laboratory
testing is useful for monitoring the patient and evaluating
complications. Routine laboratory studies for all exposed
patients include CBC, glucose, and electrolyte determinations.
Additional tests for patients who have substantial benzene
exposure include ECG monitoring, urinalysis, determinations
of BUN, creatinine, and liver function test. Chest radiography
and pulse oximetry (or ABG measurements) are recommended for
severe inhalation exposure or if pulmonary aspiration is suspected.
Blood levels of benzene or phenol, a
metabolite of benzene, may be used to document exposure, although
they are not useful clinically. The OSHA benzene standard
mandates that urinary phenol-testing be performed on all workers
exposed to benzene in an emergency situation (see Follow-up
below). However, other factors that may contribute to a high
phenol level must be evaluated, such as ingestion of benzoate
preservatives, certain medications (e.g., Pepto-Bismol and
Chloraseptic), and smoking. Other urinary metabolites of benzene
can also be used to document exposure. The ACGIH biological
exposure index for benzene is 25 µg S-phenyl-N-acetyl
cysteine (PhAC)/g creatinine, and muconic acid is also a sensitive
marker of benzene.
Disposition and Follow-up
Consider hospitalizing symptomatic patients
who have significant inhalation exposure and patients who
have ingested large amounts of benzene.
Delayed Effects
Observe hospitalized patients for signs
of acute tubular necrosis, encephalopathy, and dysrhythmias.
In addition, patients exposed by inhalation should be observed
for signs of pulmonary edema, and those who have ingested
benzene should be watched for signs of aspiration pneumonitis,
which can occur up to 72 hours after exposure.
Patient Release
Patients who have remained asymptomatic
6 to 12 hours after exposure may be discharged, advised to
rest and to seek medical care promptly if symptoms develop
(see the Benzene-Patient Information Sheet below).
Follow-up
Obtain the name of the patient's primary
care physician so that the hospital can send a copy of the
ED visit to the patient's doctor.
Patients who have received significant
exposures (as determined by histories or clinical signs and
symptoms such as dysrhythmias, syncope, or confusion) should
be monitored for hematopoietic effects. OSHA mandates that
acutely exposed workers who have urinary phenol levels above
75 mg/L receive periodic CBCs (at least monthly for 3 months)
to monitor potential bone marrow effects. Patients who have
corneal injuries should be reexamined within 24 hours.
Reporting
If a work-related incident has occurred,
you may be legally required to file a report; contact your
state or local health department.
Other persons may still be at risk in
the setting where this incident occurred. If the incident
occurred in the workplace, discussing it with company personnel
may prevent future incidents. If a public health risk exists,
notify your state or local health department or other responsible
public agency. When appropriate, inform patients that they
may request an evaluation of their workplace from OSHA or
NIOSH. See Appendices III and IV for a list of agencies that
may be of assistance.
Patient Information Sheet
This handout provides information and
follow-up instructions for persons who have been exposed to
benzene.
Print this handout only.pdf icon[32 KB]
What is benzene?
Benzene is a clear, colorless liquid
with a sweet odor when in pure form. It burns readily. Benzene
is obtained from crude petroleum. Small amounts may be found
in products such as cigarette smoke, paints, glues, pesticides,
and gasoline.
What immediate health effects can result from benzene exposure?
Breathing benzene vapor in small amounts
can cause headache, dizziness, drowsiness, or nausea. With
more serious exposure, benzene may cause sleepiness, stumbling,
irregular heartbeats, fainting, or even death. Benzene vapors
are mildly irritating to the skin, eyes, and lungs. If liquid
benzene contacts the skin or eyes, it may cause burning pain.
Liquid benzene splashed in the eyes can damage the eyes. The
degree of symptoms depends on the amount of exposure. Special
consideration regarding the exposure of pregnant women is
warranted since benzene has been shown to have a small negative
effect on genes and crosses the placenta; thus, medical counseling
is recommended for the acutely exposed pregnant woman.
Can benzene poisoning be treated?
There is no specific antidote for benzene,
but its effects can be treated, and most exposed persons recover
fully. Persons who have experienced serious symptoms may need
to be hospitalized.
Are any future health effects likely to occur?
A single small exposure from which a
person recovers quickly is not likely to cause delayed or
long-term effects. After a severe exposure, some symptoms
may take a few days to develop. Repeated exposure to benzene
may cause a blood disorder (i.e., aplastic anemia and pancytopenia)
and cancer of blood-forming cells (i.e., leukemia). Aplastic
anemia and leukemia have been reported in some workers exposed
repeatedly to benzene over long periods of time.
What tests can be done if a person has been exposed to benzene?
Specific tests for the presence of benzene
in blood generally are not useful to the doctor. Phenol, muconic
acid or S-phenyl-N-acetyl cysteine (PhAC), breakdown products
of benzene, can be measured in urine to prove benzene exposure.
Other tests may show whether injury has occurred in the heart,
kidneys, blood, or nervous system. Testing is not needed in
every case.
Where can more information about benzene be found?
More information about benzene can be
obtained from your regional poison control center; your state,
county, or local health department; the Agency for Toxic Substances
and Disease Registry (ATSDR); your doctor; or a clinic in
your area that specializes in occupational and environmental
health. If the exposure happened at work, you may wish to
discuss it with your employer, the Occupational Safety and
Health Administration (OSHA), or the National Institute for
Occupational Safety and Health (NIOSH). Ask the person who
gave you this form for help in locating these telephone numbers.
Follow-up Instructions
Keep this page and take it with you to
your next appointment. Follow only the instructions
checked below.
Print instructions onlypdf icon[32 KB]
[ ] Call your doctor or the Emergency
Department if you develop any unusual signs or symptoms within
the next 24 hours, especially:
- eye and skin irritation
- bronchial irritation, cough, hoarseness, tightness in
chest
- drowsiness, dizziness, headache, convulsions
- irregular heart beats
[ ] No follow-up appointment is necessary
unless you develop any of the symptoms listed above.
[ ] Call for an appointment with Dr.____
in the practice of ________.
When you call for your appointment, please
say that you were treated in the Emergency Department at _________
Hospital by________and were advised to be seen again in ____days.
[ ] Return to the Emergency Department/Clinic
on ____ (date) at _____ AM/PM for a follow-up examination.
[ ] Do not perform vigorous physical
activities for 1 to 2 days.
[ ] You may resume everyday activities
including driving and operating machinery.
[ ] Do not return to work for _____days.
[ ] You may return to work on a limited
basis. See instructions below.
[ ] Avoid exposure to cigarette smoke
for 72 hours; smoke may worsen the condition of your lungs.
[ ] Avoid drinking alcoholic beverages
for at least 24 hours; alcohol may worsen injury to your stomach
or have other effects.
[ ] Avoid taking the following medications:
________________
[ ] You may continue taking the following
medication(s) that your doctor(s) prescribed for you: _______________________________
[ ] Other instructions:
____________________________________
_____________________________________________________
- Provide the Emergency Department with the name and the
number of your primary care physician so that the ED can
send him or her a record of your emergency department visit.
- You or your physician can get more information on the
chemical by contacting: ____________ or _____________, or by
checking out the following Internet Web sites:
___________;__________.
Signature of patient _______________ Date ____________
Signature of physician _____________ Date ____________
Where can I get more information?
If you have questions or concerns, please contact your community or state health or environmental quality department or:
For more information, contact:
Agency for Toxic Substances and Disease Registry
Division of Toxicology and Human Health Sciences
4770 Buford Highway
Chamblee, GA 30341-3717
Phone: 1-800-CDC-INFO 888-232-6348 (TTY)
Email: Contact CDC-INFO
ATSDR can also tell you the location of occupational and environmental health clinics. These clinics specialize in recognizing, evaluating, and treating illnesses resulting from exposure to hazardous substances.