Medical Management Guidelines for Selenium Hexafluoride(SeF6)
CAS# 7783-79-1
UN# 2194
PDF Versionpdf icon[183 KB]
Synonyms include selenium fluoride and selenium (VI) fluoride.
- Persons exposed only to selenium hexafluoride gas do not pose secondary contamination risks.
- At room temperature, selenium hexafluoride is a colorless gas. It is not highly flammable, but when heated to high temperatures, it may decompose to produce toxic fumes (fluoride and selenium). Vapors from the liquified gas are initially heavier than air and spread along the ground. The odor of selenium hexafluoride may not provide adequate warning of hazardous concentrations.
- Selenium hexafluoride is absorbed by the lungs. Exposure causes inflammation and irritation of the skin, respiratory tract, and mucous membranes. Pulmonary edema may also occur after inhalation. Contact with the liquified gas may cause burns, severe injury, or frostbite.
General Information
Description
Selenium hexafluoride is a colorless
gas at room temperature. It is corrosive and highly toxic.
Selenium hexafluoride should be stored in a cool, fireproof
building with ventilation along the floor. Selenium
hexafluoride is insoluble in water.
Routes of Exposure
Inhalation
Inhaled selenium hexafluoride is a
highly toxic, corrosive, and irritating gas. It is absorbed
from the lungs and is irritating to the upper respiratory
tract even at low concentrations. No data as to odor
threshold were located; odor may not provide an adequate
warning of potentially hazardous concentrations.
Selenium hexafluoride vapor is heavier than air, and
asphyxiation in enclosed, poorly ventilated, or low-lying
areas is possible.
Children exposed to the same levels of
selenium hexafluoride vapor as adults may receive a larger
dose because they have greater lung surface area:body weight
ratios and higher minute volume: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 selenium hexafluoride vapor found nearer to the
ground.
Skin/Eye Contact
Direct contact with selenium
hexafluoride gas causes rapid and severe eye and skin
irritation or burns. Exposure to the liquified gas may
produce burns, severe injury or frostbite.
Children are more vulnerable to
toxicants affecting the skin because of their relatively
larger surface area:body weight ratio. 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
selenium hexafluoride found nearer to the ground.
Ingestion
Selenium hexafluoride is a gas at room
temperature and ingestion is therefore unlikely.
Sources/Uses
Selenium hexafluoride is prepared by
passing gaseous fluoride over finely divided selenium in a
copper vessel.
Selenium hexafluoride is used as a
gaseous electrical insulator.
Standards and Guidelines
OSHA PEL (permissible exposure limit) =
0.05 ppm, as selenium.
NIOSH IDLH (immediately dangerous to
life or health) = 2 ppm.
Physical Properties - Calcium Hypochlorite
Description: Colorless gas
Warning properties: none
Molecular weight: 192.95 daltons
Boiling point (760 mm Hg):
sublimes at -51.88°F (-46.6°C)
Freezing point: - 59.44°F
(-50.8°C)
Vapor pressure: 651.2 mm Hg at
-55.66°F (-48.7°C)
Gas density: 6.7 (air = 1)
Specific gravity: 3.25 at -28°C
(water = 1)
Water solubility: insoluble
Flammability: not flammable
Flammable range: not flammable
Incompatibilities
Selenium hexafluoride reacts with
water. Selenium hexafluoride also reacts with ammonia gas at
200°C to give selenium, nitrogen, and hydrogen fluoride.
Health Effects
- Selenium hexafluoride gas is corrosive and severely
irritating to skin, eyes, and mucous membranes. Inhalation
of selenium hexafluoride results in respiratory distress and
pulmonary edema. Contact with the skin or eyes produces
irritation and lacrimation, and can result in chemical
burns, permanent tissue damage, or blindness. Contact with
the liquified gas may cause burns, severe injury, or
frostbite.
- Selenium hexafluoride decomposes into selenium and
hydrofluoric acid on contact with moisture. No information
was found as to whether the health effects of selenium
hexafluoride in children are different than in adults.
Exposure to selenium hexafluoride produces severe
respiratory problems and individuals with pre-existing
breathing difficulties or skin disease may be more
susceptible to its effects.
Acute Exposure
Selenium hexafluoride decomposes into
selenium and hydrofluoric acid on contact with moisture.
Onset of irritation is immediate, but pulmonary edema may be
delayed several hours. Burns and damage to the eyes are
progressive while any unneutralized fluoride ion remains.
Children do not always respond to
chemicals in the same way that adults do. Different
protocols for managing their care may be needed.
Respiratory
Selenium hexafluoride produces
irritation of the respiratory-tract, and can lead to
pulmonary edema and death.
Children may be more vulnerable to
corrosive agents because of the smaller diameter of their
airways.
Children may be more vulnerable because
of relatively higher minute ventilation per kg and failure
to evacuate an area promptly when exposed.
Dermal
Selenium hexafluoride is a skin
irritant. Contact with the liquified gas may cause burns,
severe injury or frostbite. Burns are progressive while any
unneutralized fluoride ion remains.
Because of their relatively larger
surface area:body weight ratio, children are more vulnerable
to toxicants affecting the skin.
Ocular/Ophthalmic
Selenium hexafluoride gas can cause eye
irritation and damage to the cornea, exposure to the
liquified gas can cause severe damage or blindness. Damage
to the eyes is progressive while any unneutralized fluoride
ion remains.
Potential Sequelae
Tissue damage may be permanent; damage
to the eyes may cause blindness. Exposure to selenium
hexafluoride may result in electrolyte imbalance Selenium
hexafluoride may trigger electrolyte imbalance similar to
that elicited by hydrogen fluoride, since selenium
hexafluoride readily decomposes to selenium and hydrogen
fluoride upon contact with moisture. Refer to the Medical
Management Guidelines for hydrogen fluoride for additional
information.
Chronic Exposure
Repeated contact with low
concentrations of selenium hexafluoride may cause
dermatitis, systemic toxicity characteristic of chronic
selenium exposure, or fluorosis, a degenerative bone
condition.
Chronic exposure may be more serious
for children because of their potential longer latency
period.
Carcinogenicity
Selenium hexafluoride has not been
classified for carcinogenicity.
Reproductive and Developmental Effects
No studies were located that address
reproductive or developmental effects of selenium
hexafluoride in humans. Selenium hexafluoride 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.
Prehospital Management
- Victims exposed only to selenium hexafluoride gas do not
pose contamination risks to rescuers.
- Selenium hexafluoride is corrosive and irritating to
mucous membranes, skin, eyes, and the respiratory system.
Acute inhalation exposure may lead to respiratory distress
and noncardiogenic pulmonary edema.
- There is no antidote for selenium hexafluoride.
Treatment consists of respiratory and cardiovascular
support.
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
Selenium hexafluoride is a highly toxic
gas, it is corrosive and severely irritating to the eyes,
mucous membranes, respiratory tract, and skin. Selenium
hexafluoride is not flammable, but when heated, decomposes
to produce irritating, corrosive, and/or toxic gases.
Respiratory Protection:
Positive-pressure, self-contained breathing apparatus (SCBA)
is recommended in response situations that involve exposure
to potentially unsafe levels of selenium hexafluoride.
Skin Protection:
Chemical-protective clothing is recommended because selenium
hexafluoride can cause skin irritation and burns. Fully
encapsulating, vapor protective clothing should be worn to
deal with spills or leaks with no fire.
ABC Reminders
Quickly establish 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
anxiety in victims with chemically-induced acute disorders,
especially children who may suffer separation anxiety if
separated from a parent or other adult.
Decontamination Zone
Patients exposed only to selenium
hexafluoride vapor who have no skin or eye irritation may be
transferred immediately to the Support Zone. Other patients
will 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 establish 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 may assist with
their own decontamination. Decontamination is important as
burns and damage to the eyes are progressive while any
unneutralized fluoride ion remains.
Flush exposed skin and hair with
copious amounts of water. Wash with soap and rinse
thoroughly with water. Use caution to avoid hypothermia when
decontaminating victims, particularly children or the
elderly. Use blankets or warmers after decontamination as
needed.
Flush exposed or irritated eyes with
tepid water for 15 minutes. Remove contact lenses if easily
removable without additional trauma to the eye. Continue eye
irrigation during other basic care and transport. If pain or
injury is evident, continue irrigation while transferring
the victim to the Support Zone.
Consider appropriate management of
chemically contaminated children at the exposure site.
Provide reassurance to the child during decontamination,
especially if separation from a parent occurs.
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). Victims who have undergone decontamination or have
been exposed only to vapor pose no serious risks of
secondary contamination to rescuers. In such cases, Support
Zone personnel require no specialized protective gear.
ABC Reminders
Quickly establish 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.
Administer supplemental oxygen as required and establish
intravenous access if necessary. Place on a cardiac monitor,
if available.
In cases of contact with liquid
(compressed gas), gently wash frosted skin with water;
gently remove clothing from affected area. Dry with clean
towels and keep victim warm and quiet.
Additional Decontamination
Continue irrigating exposed skin and
eyes, as appropriate.
Advanced Treatment
Treat cases of respiratory compromise,
coma, or excessive pulmonary secretions with respiratory
support using protocols and techniques available and within
the scope of training. Some cases may necessitate procedures
such as endotracheal intubation or cricothyroidotomy by
properly trained and equipped personnel.
Treat patients who have bronchospasm
with an aerosolized bronchodilator such as albuterol.
Administer corticosteroids as indicated to patients who have
persistent wheezing or hypersensitivity pneumonitis.
Consider racemic epinephrine aerosol
for children who develop stridor. Dose 0.25-0.75 mL of 2.25%
racemic epinephrine solution in water, repeat every
20 minutes as needed, cautioning for myocardial variability.
Patients who are comatose, hypotensive,
or having seizures or cardiac arrhythmias should be treated
according to advanced life support (ALS) protocols.
Transport to Medical Facility
Only decontaminated patients or
patients not requiring decontamination should be transported
to a medical facility. "Body bags" 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.
Multi-Casualty Triage
Consult with the base station physician
or the regional poison control center for advice regarding
triage of multiple victims.
Patients who are seriously symptomatic
(as in cases of chest tightness or wheezing), and patients
who have histories or evidence of significant exposure
should be transported to a medical facility for evaluation.
Others may be discharged at the scene after their names,
addresses, and telephone numbers are recorded. Those
discharged should be advised to seek medical care promptly
if symptoms develop (see Patient Information Sheet
below).
Emergency Department Management
- Patients do not pose a contamination risk to hospital
personnel.
- Selenium hexafluoride is corrosive and irritating to
mucous membranes, skin, eyes, and the respiratory tract.
Acute inhalation exposure may lead to respiratory distress
and noncardiogenic pulmonary edema.
- There is no antidote for selenium hexafluoride.
Treatment consists of respiratory and cardiovascular
support.
Decontamination Area
Unless previously decontaminated, all
victims with skin or eye irritation require decontamination
as described below. All other patients may be transferred
immediately to the Critical Care Area.
Because of their relatively larger
surface area:body 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
Treat cases of respiratory compromise,
coma, or excessive pulmonary secretions with respiratory
support using protocols and techniques available and within
the scope of training. Some cases may necessitate procedures
such as endotracheal intubation or cricothyroidotomy by
properly trained and equipped personnel.
Treat patients who have bronchospasm
with an aerosolized bronchodilator such as albuterol.
Administer corticosteroids as indicated to patients who have
persistent wheezing or hypersensitivity pneumonitis.
Consider racemic epinephrine aerosol
for children who develop stridor. Dose 0.25-0.75 mL of 2.25%
racemic epinephrine solution in water, repeat every
20 minutes as needed, cautioning for myocardial variability.
Patients who are comatose, hypotensive,
or have seizures or ventricular arrhythmias should be
treated in the conventional manner.
Basic Decontamination
Patients who are able may assist with
their own decontamination. Decontamination is important as
burns and damage to the eyes are progressive while any
unneutralized fluoride ion remains.
Flush exposed skin and hair with water
for 2 to 3 minutes (preferably under a shower), then wash
thoroughly with mild soap. Rinse thoroughly with water. In
case of frostbite injury, irrigate with lukewarm (42°C)
water according to standard treatment. Use caution to avoid
hypothermia when decontaminating victims, particularly
children or the elderly. Use blankets or warmers after
decontamination as needed.
Flush exposed eyes with plain tepid
water for at least 15 minutes. Remove contact lenses if
easily removable without additional trauma to the eye. If
pain or injury is evident, continue irrigation while
transporting the patient to the Critical Care Area.
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 under
Decontamination Zone. Establish intravenous access in
seriously ill patients if this has not been done previously.
Continuously monitor cardiac rhythm.
Patients who are comatose, hypotensive,
or have seizures or cardiac arrhythmias should be treated in
the conventional manner.
Inhalation Exposure
Administer supplemental oxygen by mask
to patients who have respiratory symptoms. Treat patients
who have bronchospasm with an aerosolized bronchodilator
such as albuterol. Administer corticosteroids as indicated
to patients who have persistent wheezing or hypersensitivity
pneumonitis.
Consider racemic epinephrine aerosol
for children who develop stridor. Dose 0.25-0.75 mL of 2.25%
racemic epinephrine solution in water, repeat every
20 minutes as needed, cautioning for myocardial variability.
Skin Exposure
If the skin was in contact with
selenium hexafluoride gas chemical burns may occur; treat as
thermal burns. Flush exposed skin for at least 20 minutes.
Contact with the liquified gas may produce frostbite. In
case of frostbite injury, irrigate with lukewarm (42°C)
water according to standard treatment. Burns may be treated
with a calcium gluconate gel or slurry in water or glycerine
to remove fluoride ions and relieve pain.
Because of their relatively larger
surface area:body weight ratio, children are more vulnerable
to toxicants affecting the skin.
Eye Exposure
Continue irrigation for at least
15 minutes. In case of frostbite injury, ensure that
thorough warming with lukewarm water or saline has been
completed. Test visual acuity. Examine the eyes for corneal
damage and treat appropriately. Immediately consult an
ophthalmologist for patients who have corneal injuries.
Antidotes and Other Treatments
There is no antidote for selenium
hexafluoride. Treatment is supportive of respiratory and
cardiovascular functions.
DERMAL EXPOSURE: Patients should be treated in a stepwise manner based on their response to therapy. The initial treatment for pain from dermal exposure is topical calcium. One method for making a gel is to mix calcium gluconate with methylcellulose or water-soluble lubricant in a 1:2 ratio. Apply the gel to the affected areas as frequently as needed to relieve symptoms. If the patient has pain despite topical therapy, extremity burns can be treated with a regional infusion of 40 mL of 2.5% calcium gluconate solution using a Bier block. If this is not successful, an intra-arterial infusion of 40 mL of 2.5% calcium gluconate can be performed. If the area affected is not on an extremity, inject 0.3 to 0.5 mL/cm(2) of 2.5% calcium gluconate into the region.
Laboratory Tests
Routine laboratory studies for all
exposed patients include CBC, glucose, and electrolyte
determinations. An EKG should be performed if significant
exposure is suspected. Patients who have respiratory
complaints may require pulse oximetry (or ABG measurements),
chest radiography, and peak-flow spirometry.
Disposition and Follow-up
Consider hospitalizing patients who
have histories of significant inhalation exposure and are
symptomatic (e.g., chest tightness or wheezing).
Delayed Effects
Pulmonary edema may be delayed for
several hours after inhalation exposure. Burns and damage to
the eyes are progressive while any unneutralized fluoride
ion remains.
Patient Release
Patients who remain asymptomatic for 24
hours after exposure may be discharged with instructions to
seek medical care promptly if symptoms develop (see the
Selenium hexafluoride--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.
If significant inhalation or skin
contact has occurred, monitor pulmonary function.
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 Appendix III 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
selenium hexafluoride.
Print this handout only.pdf icon[49.5 KB]
What is selenium hexafluoride?
Selenium hexafluoride is a corrosive,
colorless gas. Selenium hexafluoride is used as a gaseous
electrical insulator.
What immediate health effects can be caused by exposure to selenium hexafluoride?
Low levels of selenium hexafluoride in
the air can irritate the eyes, nose, throat, and lungs and
cause cough, chest tightness, and shortness of breath.
Higher levels can cause a build-up of fluid in the lungs,
which may cause death. If the liquified gas comes in contact
with the skin or eyes, it can cause severe burns or
frostbite. Generally, the more serious the exposure, the
more severe the symptoms.
Can selenium hexafluoride poisoning be treated?
There is no antidote for selenium
hexafluoride, but its effects can be treated and most
exposed persons get well. Seriously exposed persons may need
to be hospitalized.
Are any future health effects likely to occur?
In rare cases, after exposure to
selenium hexafluoride, certain persons can develop allergies
in which even small exposures to selenium hexafluoride or
other irritants can trigger skin irritation. Therefore, it
is important to tell your doctor that you have been exposed
to selenium hexafluoride.
What tests can be done if a person has been exposed to selenium hexafluoride?
Specific tests for the presence of
selenium hexafluoride in blood are not available. If a
severe exposure has occurred, respiratory function tests and
a chest x-ray may show whether damage has been done to the
lungs. Testing is not needed in every case.
Where can more information about selenium hexafluoride be found?
More information about selenium
hexafluoride 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 only.pdf icon[49.5 KB]
[ ] Call your doctor or the Emergency
Department if you develop any unusual signs or symptoms
within the next 24 hours, especially:
- coughing, wheezing, difficulty breathing, shortness of
breath, or chest pain
- increased pain or a discharge from your eyes
- increased redness or pain or a pus-like discharge in
the area of a skin burn
[ ] 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.