Chronic Exposure
The major concerns of repeated formaldehyde exposure are sensitization and cancer. In sensitized persons, formaldehyde can cause asthma and contact dermatitis. In persons who are not sensitized, prolonged inhalation of formaldehyde at low levels is unlikely to result in chronic pulmonary injury. Adverse effects on the central nervous system such as increased prevalence of headache, depression, mood changes, insomnia, irritability, attention deficit, and impairment of dexterity, memory, and equilibrium have been reported to result from long-term exposure. Chronic exposure may be more serious for children because of their potential longer latency period.
Formaldehyde (HCHO)
CAS 50-00-0; UN 1198, UN 2209 (formalin)
Synonyms include formalin, formic aldehyde, methanal, methyl aldehyde, methylene oxide, oxomethane,
and paraform.
C Persons exposed only to formaldehyde vapor do not pose substantial risks of
secondary contamination. Persons whose clothing or skin is contaminated with a
solution of formaldehyde can cause secondary contamination by direct contact or
through off-gassing vapor.
• Formaldehyde is a colorless, highly toxic, and flammable gas at room temperature
that is slightly heavier than air. It has a pungent, highly irritating odor that is
detectable at low concentrations, but may not provide adequate warning of
hazardous concentrations for sensitized persons.
• It is used most often in an aqueous solution stabilized with methanol (formalin).
• Most formaldehyde exposures occur by inhalation or by skin or eye contact.
Formaldehyde is absorbed well by the lungs, gastrointestinal tract, and, to a lesser
extent, skin.
Description Formaldehyde is a nearly colorless gas with a pungent, irritating
odor even at very low concentrations (below 1 ppm). Its vapors
are flammable and explosive. Because the pure gas tends to
polymerize, it is commonly used and stored in solution.
Formalin, the aqueous solution of formaldehyde (30% to 50%
formaldehyde), typically contains up to 15% methanol as a
stabilizer.
Routes of Exposure
Inhalation Most formaldehyde exposures occur by inhalation or by skin/eye
contact. Formaldehyde vapor is readily absorbed from the lungs.
In cases of acute exposure, formaldehyde will most likely be
detected by smell; however, persons who are sensitized to
formaldehyde may experience headaches and minor eye and
airway irritation at levels below the odor threshold (odor
threshold is 0.5 to 1.0 ppm; OSHA PEL is 0.75 ppm). For
sensitized persons, odor is not an adequate indicator of
formaldehyde’s presence and may not provide reliable
warning of hazardous concentrations. Odor adaptation can
occur. Low-dose acute exposure can result in headache, rhinitis,
and dyspnea; higher doses may cause severe mucous membrane
irritation, burning, and lacrimation, and lower respiratory effects
ATSDR • General Information 1
Formaldehyde
Skin/Eye Contact
Ingestion
Sources/Uses
such as bronchitis, pulmonary edema, or pneumonia. Sensitive
individuals may experience asthma and dermatitis, even at very
low doses. Formaldehyde vapors are slightly heavier than air and
can result in asphyxiation in poorly ventilated, enclosed, or low-
lying areas.
Children exposed to the same levels of formaldehyde as adults
may receive larger doses 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 formaldehyde found nearer to the ground.
Ocular exposure to formaldehyde vapors produces irritation and
lacrimation. Depending on the concentration, formaldehyde
solutions may cause transient discomfort and irritation or more
severe effects, including corneal opacification and loss of vision.
Formaldehyde is absorbed through intact skin and may cause
irritation or allergic dermatitis; rapid metabolism makes systemic
effects unlikely following dermal exposure.
Children are more vulnerable to toxicants absorbed through the
skin because of their relatively larger surface area:body weight
ratio.
Ingestion of as little as 30 mL (1 oz.) of a solution containing
37% formaldehyde has been reported to cause death in an adult.
Ingestion may cause corrosive injury to the gastrointestinal
mucosa, with nausea, vomiting, pain, bleeding, and perforation.
Corrosive injuries are usually most pronounced in the pharyngeal
mucosa, epiglottis and esophagus. Systemic effects include
metabolic acidosis, CNS depression and coma, respiratory
distress, and renal failure.
Formaldehyde is synthesized by the oxidation of methanol. It is
among the 25 most abundantly produced chemicals in the world
and is used in the manufacture of plastics, resins, and urea-
formaldehyde foam insulation. Formaldehyde or formaldehyde-
containing resins are used in the manufacture of chelating agents,
a wide variety of organic products, glass mirrors, explosives,
artificial silk, and dyes. It has been used as a disinfectant,
germicide, and in embalming fluid. In the agricultural industry,
formaldehyde has been used as a fumigant, preventative for
mildew in wheat and rot in oats, a germicide and fungicide for
plants, an insecticide, and in the manufacture of slow-release
fertilizers. Formaldehyde is found in construction materials such
as plywood adhesives. Formaldehyde also is or has been used in
2 General Information • ATSDR
Formaldehyde
the sugar, rubber, food, petroleum, pharmaceuticals, and textiles
industries.
Standards and
Guidelines
OSHA PEL (permissible exposure limit) = 0.75 ppm (averaged
over an 8-hour workshift)
OSHA STEL (short-term exposure limit) = 2 ppm (15 minute
exposure)
NIOSH IDLH (immediately dangerous to life or health) =
20 ppm
AIHA ERPG-2 (emergency response planning guideline) (the
maximum airborne concentration below which it is believed that
nearly all individuals could be exposed for up to 1 hour without
experiencing or developing irreversible or other serious health
effects or symptoms which could impair an individual’s ability to
take protective action) = 10 ppm
Physical Properties Description: Nearly colorless gas with a pungent, irritating odor
Warning properties: Odor is detectable at less than 1 ppm, but
many sensitive persons experience symptoms below the odor
threshold.
Molecular weight: 30.0 daltons
Boiling point (760 mm Hg): - 6 EF (-21 EC)
Vapor pressure: 3883 mm Hg at 77EF (25 EC)
Gas density: 1.07 (air = 1)
Water solubility: 55% at 68 EF (20 EC)
Flammability: Flammable gas between 7% and 73% at 77 EF
(25 EC) (concentration in air); combustible liquid (formalin)
Incompatibilities Formaldehyde reacts with strong oxidizers, alkalis, acids,
phenols, and urea. Pure formaldehyde has a tendency to
polymerize.
ATSDR • General Information 3
Formaldehyde
4 General Information • ATSDR
Formaldehyde
Health Effects
C Formaldehyde is an eye, skin, and respiratory tract irritant. Inhalation of vapors can
produce narrowing of the bronchi and an accumulation of fluid in the lungs.
• Children may be more susceptible than adults to the respiratory effects of
formaldehyde.
• Formaldehyde solution (formalin) causes corrosive injury to the gastrointestinal
tract, especially the pharynx, epiglottis, esophagus, and stomach.
C The systemic effects of formaldehyde are due primarily to its metabolic conversion to
formate, and may include metabolic acidosis, circulatory shock, respiratory
insufficiency, and acute renal failure.
C Formaldehyde is a potent sensitizer and a probable human carcinogen.
Acute Exposure Formaldehyde vapor produces immediate local irritation in
mucous membranes, including eyes, nose, and upper respiratory
tract. Ingestion of formalin causes severe injury to the
gastrointestinal tract. The exact mechanism of action of
formaldehyde toxicity is not clear, but it is known that it can
interact with molecules on cell membranes and in body tissues
and fluids (e.g., proteins and DNA) and disrupt cellular
functions. High concentrations cause precipitation of proteins,
which results in cell death. Absorption from the respiratory tract
is very rapid; absorption from the gastrointestinal tract is also
rapid, but may be delayed by ingestion with food. Once
absorbed, formaldehyde is metabolized to formic acid, which
may cause acid-base imbalance and a number of other systemic
effects.
Children do not always respond to chemicals in the same way
that adults do. Different protocols for managing their care may
be needed.
CNS Malaise, headache, sleeping disturbances, irritability, and
impairment of dexterity, memory, and equilibrium may result
from a single, high level, exposure to formaldehyde.
Respiratory Even fairly low concentrations of formaldehyde can produce
rapid onset of nose and throat irritation, causing cough, chest
pain, shortness of breath, and wheezing. Higher exposures can
cause significant inflammation of the lower respiratory tract,
resulting in swelling of the throat, inflammation of the windpipe
ATSDR • Health Effects 5
Formaldehyde
Metabolic
Immunologic
Gastrointestinal
Ocular
and bronchi, narrowing of the bronchi, inflammation of the
lungs, and accumulation of fluid in the lungs. Pulmonary injury
may continue to worsen for 12 hours or more after exposure.
Previously sensitized individuals can develop severe narrowing
of the bronchi at very low concentrations (e.g., 0.3 ppm).
Bronchial narrowing may begin immediately or can be delayed
for 3 to 4 hours; effects may worsen for up to 20 hours after
exposure and can persist for several days.
Exposure to certain chemical irritants can lead to Reactive
Airway Dysfunction Syndrome (RADS), a chemically- or
irritant-induced type of asthma.
Children may be more vulnerable to corrosive agents than adults
because of the relatively smaller diameter of their airways.
Children may be more vulnerable because of relatively increased
minute ventilation per kg and failure to evacuate an area
promptly when exposed.
Accumulation of formic acid can cause an anion-gap acid-base
imbalance. If formalin is ingested, absorption of the methanol
stabilizer may contribute to the imbalance and can result in an
osmolal gap, as well as an anion gap.
In persons who have been previously sensitized, inhalation and
skin contact may cause various skin disorders, asthma-like
symptoms, anaphylactic reactions and, rarely, hemolysis. The
immune system in children continues to develop after birth, and
thus, children may be more susceptible to certain chemicals.
Ingestion of aqueous solutions of formaldehyde can result in
severe corrosive injury to the esophagus and stomach. Nausea,
vomiting, diarrhea, abdominal pain, inflammation of the stomach,
and ulceration and perforation of the oropharynx, epiglottis,
esophagus, and stomach may occur. Both formaldehyde and the
methanol stabilizer are easily absorbed and can contribute to
systemic toxicity.
Exposure to low concentrations of formaldehyde vapor can
cause eye irritation, which abates within minutes after exposure
has ended. Formalin splashed in the eyes can result in corneal
ulceration or cloudiness of the eye surface, death of eye surface
cells, perforation, and permanent loss of vision; these effects may
be delayed for 12 hours or more.
6 Health Effects • ATSDR
Formaldehyde
Dermal Exposure to formaldehyde vapor or to formalin solutions can
cause skin irritation and burns. In sensitized persons, contact
dermatitis may develop at very low exposure levels.
Potential Sequelae In survivors of inhalation injury, pulmonary function usually
returns to normal. Eye exposure to high concentrations of
formaldehyde vapor or formalin can eventually cause blindness.
Narrowing of the esophagus and severe corrosive damage to the
stomach lining can result from ingesting formalin.
Chronic Exposure The major concerns of repeated formaldehyde exposure are
sensitization and cancer. In sensitized persons, formaldehyde can
cause asthma and contact dermatitis. In persons who are not
sensitized, prolonged inhalation of formaldehyde at low levels is
unlikely to result in chronic pulmonary injury. Adverse effects on
the central nervous system such as increased prevalence of
headache, depression, mood changes, insomnia, irritability,
attention deficit, and impairment of dexterity, memory, and
equilibrium have been reported to result from long-term
exposure. 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 formaldehyde may reasonably be anticipated to be a
carcinogen. In humans, formaldehyde exposure has been weakly
associated with increased risk of nasal cancer and nasal tumors
Reproductive and
Developmental Effects
were observed in rats chronically inhaling formaldehyde.
There is limited evidence that formaldehyde causes adverse
reproductive effects. The TERIS database states that the risk of
developmental defects to the exposed fetus ranges from none to
minimal. Formaldehyde is not included in Reproductive and
Developmental Toxicants, a 1991 report published by the U.S.
General Accounting Office (GAO) that lists 30 chemicals widely
acknowledged to have reproductive and developmental
consequences.
There have been reports of menstrual disorders in women
occupationally exposed to formaldehyde, but they are
controversial. Studies in experimental animals have reported
some effects on spermatogenesis. Formaldehyde has not been
proven to be teratogenic in animals and is probably not a human
teratogen at occupationally permissible levels. Formaldehyde has
been shown to have genotoxic properties in human and
laboratory animal studies producing sister chromatid exchange
and chromosomal aberrations.
ATSDR • Health Effects 7
Formaldehyde
Special consideration regarding the exposure of pregnant women
is warranted, since formaldehyde has been shown to be a
genotoxin; thus, medical counseling is recommended for the
acutely exposed pregnant woman.
8 Health Effects • ATSDR
Formaldehyde
Prehospital Management
C Victims exposed only to formaldehyde gas do not pose significant risks of secondary
contamination to personnel outside the Hot Zone. Victims whose clothing or skin is
contaminated with a formaldehyde-containing solution (formalin) can secondarily
contaminate personnel by direct contact or through off-gassing vapor.
C Inhalation of formaldehyde can cause airway irritation, bronchospasm, and
pulmonary edema.
C Absorption of large amounts of formaldehyde via any route can cause severe
systemic toxicity, leading to metabolic acidosis, tissue and organ damage, and coma.
C There is no antidote for formaldehyde. Treatment consists of supportive measures
including decontamination (flushing of skin and eyes with water, gastric lavage, and
administration of activated charcoal), administration of supplemental oxygen,
intravenous sodium bicarbonate and/or isotonic fluid, and hemodialysis.
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 Formaldehyde is a highly toxic systemic poison that is absorbed
well by inhalation. The vapor is a severe respiratory tract and
skin irritant and may cause dizziness or suffocation. Contact with
formaldehyde solution may cause severe burns to the eyes and
skin.
Respiratory Protection: Positive-pressure, self-contained
breathing apparatus (SCBA) is recommended in response
situations that involve exposure to potentially unsafe levels of
formaldehyde vapor.
Skin Protection: Chemical-protective clothing is recommended
because formaldehyde can cause skin irritation and burns.
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
ATSDR • Prehospital Management 9
Formaldehyde
Decontamination Zone
Rescuer Protection
ABC Reminders
Basic Decontamination
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.
Victims exposed only to formaldehyde vapor who have no skin
or eye irritation may be transferred immediately to the Support
Zone. All others require decontamination (see Basic
Decontamination below).
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).
Quickly access for a patent airway, ensure adequate respiration
and pulse. Stabilize the cervical spine with a collar if trauma is
suspected. Administer supplemental oxygen as required. Assist
ventilation with a bag-valve-mask device if necessary.
Victims who are able may assist with their own decontamination.
Remove and double-bag contaminated clothing and personal
belongings.
Flush liquid-exposed skin and hair with plain water for 3 to
5 minutes. Wash area thoroughly with soap and water when
possible. Use caution to avoid hypothermia when
decontaminating children or the elderly. Use blankets or warmers
when appropriate.
Irrigate exposed or irritated eyes with plain water or saline for
15 minutes. Remove contact lenses if easily removable without
additional trauma to the eye. If pain or injury is evident, continue
eye irrigation while transferring the victim to the Support Zone.
In cases of formalin ingestion, do not induce emesis. Victims
who are conscious and able to swallow should be given 4 to
8 ounces of water or milk. Gastric lavage with a small bore NG
tube should be considered if it can be performed within 1 hour
after ingestion. The effectiveness of activated charcoal
administration is unknown, but it is suggested following lavage
(administer activated charcoal 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.
10 Prehospital Management • ATSDR
Formaldehyde
Transfer to Support Zone
Support Zone
ABC Reminders
Additional Decontamination
Advanced Treatment
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.
As soon as basic decontamination is complete, move the victim
to the Support Zone.
Be certain that victims have been decontaminated properly (see
Decontamination Zone above). Persons who have undergone
decontamination or who have been exposed only to vapor pose
no serious risks of secondary contamination. Support Zone
personnel require no specialized protective gear in such cases.
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 and establish intravenous access if necessary. Place on
a cardiac monitor. Watch for signs of airway swelling and
obstruction such as progressive hoarseness, stridor, or cyanosis.
Continue irrigating exposed skin and eyes, as appropriate.
In cases of formalin ingestion, do not induce emesis. If water
has not been given previously, administer 4 to 8 ounces of milk
or water if the patient is able to swallow.
In cases of respiratory compromise secure airway and respiration
via endotracheal intubation. If not possible, perform
cricothyroidotomy if equipped and trained to do so.
Treat 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). Formaldehyde poisoning is not known to pose
additional risk during the use of bronchial or cardiac sensitizing
agents.
Consider racemic epinephrine aerosol for children who develop
stridor. Dose 0.25–0.75 mL of 2.25% racemic epinephrine
ATSDR • Prehospital Management 11
Formaldehyde
Transport to Medical Facility
Multi-Casualty Triage
solution in 2.5 cc water, repeat every 20 minutes as needed,
cautioning for myocardial variability.
Patients who are comatose, hypotensive, or have seizures or
cardiac dysrhythmias should be treated according to advanced
life support (ALS) protocols. Treat acidosis with intravenous
sodium bicarbonate (adult dose = 1 ampule; pediatric dose =
1 Eq/kg). Further bicarbonate therapy should be guided by
arterial blood gas (ABG) measurements. Hemodialysis should be
considered in patients with severe acid-base disturbances that are
refractory to conventional therapy or in cases with significant
methanol levels.
If evidence of shock or hypotension is observed begin fluid
administration. 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.
Follow with administration of dopamine (2 to 20 μg/kg/min) or
norepinephrine (0.1 to 0.2 μg/kg/min), if necessary.
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.
If formaldehyde 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.
If possible, consult with the base station physician or the regional
poison control center for advice regarding triage of multiple
victims.
Patients who have ingested formalin or have symptoms (e.g.,
severe wheezing or dyspnea) or obvious injuries (e.g., skin or
eye burns) should be transported immediately to a medical
facility for evaluation.
Patients who have no eye, skin, or throat irritation, or only mild
or transient symptoms may be released from the scene after their
names, addresses, and telephone numbers are recorded. Those
12 Prehospital Management • ATSDR
Formaldehyde
discharged should be advised to seek medical care promptly if
symptoms develop (see Patient Information Sheet below).
ATSDR • Prehospital Management 13
Formaldehyde
14 Prehospital Management • ATSDR
Formaldehyde
Emergency Department Management
C Hospital personnel in an enclosed area can be secondarily contaminated by direct
contact, by vapors off-gassing from heavily soaked clothing, or from the vomitus of
victims who have ingested formaldehyde. Patients do not pose serious contamination
risks after contaminated clothing is removed and the skin is thoroughly washed.
C Inhalation of formaldehyde can cause airway irritation, bronchospasm, and
pulmonary edema.
C Absorption of large amounts of formaldehyde via any route can cause severe
systemic toxicity, leading to metabolic acidosis, tissue and organ damage, and coma.
C There is no antidote for formaldehyde. Treatment consists of supportive measures
including decontamination (flushing of skin and eyes with water, gastric lavage, and
administration of activated charcoal), administration of supplemental oxygen,
intravenous sodium bicarbonate and/or isotonic fluid, and hemodialysis.
Decontamination Area Previously decontaminated patients and patients exposed only to
formaldehyde 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. Because
formaldehyde is absorbed (although poorly) through the skin,
don butyl rubber gloves and apron before treating patients.
Formaldehyde readily penetrates most rubbers and barrier fabrics
or creams, but butyl rubber provides good skin protection.
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:body weight ratio,
children are more vulnerable to toxicants absorbed through the
skin. Also, emergency room personnel should examine children’s
mouths for corrosive injury 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, surgically create an airway.
Treat patients who have bronchospasm with aerosolized
bronchodilators. The use of bronchial sensitizing agents in
ATSDR • Emergency Department Management 15
Formaldehyde
Basic Decontamination
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). Formaldehyde poisoning is not known to pose
additional risk during the use of bronchial or cardiac sensitizing
agents.
Consider racemic epinephrine aerosol for children who develop
stridor. Dose 0.25–0.75 mL of 2.25% racemic epinephrine
solution in 2.5 cc water, repeat every 20 minutes as needed,
cautioning for myocardial variability.
Patients who are comatose, hypotensive, or have seizures or
ventricular dysrhythmias should be treated in the conventional
manner.
Correct acidosis in the patient who has coma, seizures, or
cardiac dysrhythmias by administering intravenously sodium
bicarbonate (adult dose = 1 ampule; pediatric dose = 1 Eq/kg).
Further bicarbonate therapy should be guided by ABG
measurements. Hemodialysis should be considered in patients
with severe acid-base disturbances that are refractory to
conventional therapy or in cases with significant methanol levels.
If evidence of shock or hypotension is observed begin fluid
administration. 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.
Follow with administration of dopamine (2 to 20 μg/kg/min) or
norepinephrine (0.1 to 0.2 μg/kg/min), if necessary.
Patients who are able may assist with their own decontamination.
Because contact with formalin may cause burns, ED staff should
don chemical-resistant jumpsuits (e.g., of Tyvek or Saranex) or
butyl rubber aprons, rubber gloves, and eye protection if the
patient’s clothing or skin is wet with formalin. After the patient
has been decontaminated, no special protective clothing or
equipment is required for ED personnel.
16 Emergency Department Management • ATSDR
Formaldehyde
Critical Care Area
ABC Reminders
Quickly remove and double-bag contaminated clothing and
personal belongings. Flush exposed skin and hair with water
(preferably under a shower) for 5 minutes. If possible, wash hair
and skin with soap and water, then rinse thoroughly with water.
Use caution to avoid hypothermia when decontaminating
children or the elderly. Use blankets or warmers when
appropriate.
Flush exposed eyes with water or saline for at least 15 minutes.
Remove contact lenses if easily removable without additional
trauma to the eye. An ophthalmic anesthetic, such as 0.5%
tetracaine, may be necessary to alleviate blepharospasm, and lid
retractors may be required to allow adequate irrigation under the
eyelids. If pain or injury is evident, continue irrigation while
transporting the patient to the Critical Care Area.
In cases of formalin ingestion, do not induce emesis. If water
has not been given previously, administer 4 to 8 ounces if the
patient is alert and able to swallow. The effectiveness of
activated charcoal administration is unknown, but may be
beneficial (if not administered previously) following lavage if it
can be performed within 1 hour after ingestion (administer
activated charcoal 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. (More information is provided in
Ingestion Exposure under Critical Care Area below.)
Be certain that appropriate decontamination has been carried out
(see Decontamination Area above).
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 relatively smaller
diameter of their airways. 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 dysrhythmias should be treated in the conventional
manner. Correct acidosis in the patient who has coma, seizures,
or cardiac dysrhythmias by administering intravenously sodium
bicarbonate (adult dose = 1 ampule; pediatric dose = 1 Eq/kg).
Further bicarbonate therapy should be guided by ABG
measurements. Hemodialysis should be considered in patients
with severe acid-base disturbances that are refractory to
conventional therapy or in cases with significant methanol levels.
ATSDR • Emergency Department Management 17
Formaldehyde
Inhalation Exposure
Skin Exposure
Eye Exposure
If evidence of shock or hypotension is observed begin fluid
administration. 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.
Follow with administration of dopamine (2 to 20 μg/kg/min) or
norepinephrine (0.1 to 0.2 μg/kg/min), if necessary.
Administer supplemental oxygen by mask to patients who have
respiratory complaints. Treat 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). Formaldehyde poisoning
is not known to pose additional risk during the use of bronchial
or cardiac sensitizing agents.
Consider racemic epinephrine aerosol for children who develop
stridor. Dose 0.25–0.75 mL of 2.25% racemic epinephrine
solution in 2.5 cc water, repeat every 20 minutes as needed,
cautioning for myocardial variability.
Observe patients who are in respiratory distress for up to
12 hours and periodically repeat chest examinations and order
other appropriate studies. Follow up as clinically indicated.
If formalin or high concentrations of formaldehyde vapor were
in contact with the skin, chemical burns may result; treat as
thermal burns.
Because of their relatively larger surface area:body weight ratio,
children are more vulnerable to toxicants absorbed through the
skin.
Continue irrigation for at least 15 minutes. Test visual acuity.
Examine the eyes for corneal damage and treat appropriately.
Immediately consult an ophthalmologist for patients who have
severe corneal injuries.
18 Emergency Department Management • ATSDR
Formaldehyde
Ingestion Exposure
Antidotes and
Other Treatments
Laboratory Tests
Do not induce emesis. Give 4 to 8 ounces of water to alert
patients who can swallow if not done previously. If a large dose
has been ingested and the patient’s condition is evaluated within
30 minutes after ingestion, consider gastric lavage and
endoscopy to evaluate the extent of corrosive injury to the
gastrointestinal tract. Care must be taken when placing the
gastric tube because blind gastric-tube placement may further
injure the chemically damaged esophagus or stomach. Extreme
throat swelling may require endotracheal intubation or
cricothyriodotomy. The effectiveness of activated charcoal in
binding formaldehyde is unknown, but may be beneficial (if not
administered previously) following lavage if it can be performed
within 1 hour after ingestion (administer activated charcoal 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.
Because children do not ingest large amounts of corrosive
materials, and because of the risk of perforation from NG
intubation, lavage is discouraged in children unless intubation is
performed under endoscopic guidance.
Toxic vomitus or gastric washings should be isolated (e.g., by
attaching the lavage tube to isolated wall suction or another
closed container).
There is no antidote for formaldehyde. Treat patients who have
metabolic acidosis with sodium bicarbonate (adult dose =
1 ampule; pediatric dose = 1 Eq/kg). Further correction of
acidosis should be guided by ABG measurements.
Hemodialysis is effective in removing formic acid (formate) and
methanol and in correcting severe metabolic acidosis.
If methanol poisoning from ingestion of formalin is suspected, as
indicated by a serum methanol level of greater than 20 mg/dL or
elevated osmolal gap, start ethanol infusion. With 10% ethanol,
the loading dose is 7.5 mL/kg body weight; maintenance dose is
1.0 to 1.5 mL/kg/hour; and maintenance dose during
hemodialysis is 1.5 to 2.5 mL/kg/hour. In this setting, the target
blood level of ethanol is 0.1 mg/dL.
Routine laboratory studies for all exposed patients include CBC,
glucose, and electrolyte determinations. Additional studies for
patients exposed to formaldehyde include urinalysis (protein,
ATSDR • Emergency Department Management 19
19 Emergency Department Management • ATSDR
Formaldehyde
Disposition and
Follow-up
Delayed Effects
Patient Release
Follow-up
casts, and red blood cells may be present), methanol level,
osmolal gap, and ABG measurements (to monitor acidosis in
severe toxicity). Chest radiography and pulse oximetry may be
helpful in cases of inhalation exposure. Plasma formaldehyde
levels are not useful.
Consider hospitalizing patients who have evidence of systemic
toxicity from any route of exposure.
Patients who have substantial ingestion exposure may develop
aspiration pneumonitis or renal failure and should be admitted to
an intensive care unit for observation. Corrosive gastritis,
fibrosis of the stomach (shrinkage and contracture),
hematemesis, or edema and ulceration of the esophagus may
occur.
Patients who have inhalation exposure and who complain of
chest pain, chest tightness, or cough should be observed and
examined periodically for 6 to 12 hours to detect delayed-onset
bronchitis, pneumonia, pulmonary edema, or respiratory failure.
Formaldehyde poisoning can cause permanent alterations of
nervous system function, including problems with memory,
learning, thinking, sleeping, personality changes, depression,
headache, and sensory and perceptual changes.
Patients who are asymptomatic should be observed for 4 to
6 hours, then discharged if no symptoms occur during this
period. Advise discharged patients to seek medical care promptly
if symptoms develop (see the Formaldehyde—Patient
Information Sheet below).
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 with symptoms of seizures, convulsions, headache, or
confusion, need to be followed for permanent central nervous
system dysfunction with neurobehavioral toxicity testing, with
particular attention to problems with memory, personality
changes, and perceptual dysfunction.
Patients with injury to the mucous membranes of the respiratory
or gastrointestinal tracts should be monitored for the
development of ulceration or fibrosis.
Patients who have corneal injuries should be reexamined within
24 hours.
Formaldehyde
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.
ATSDR • Emergency Department Management 21
Formaldehyde
22 Emergency Department Management • ATSDR
Formaldehyde
Formaldehyde
Patient Information Sheet
This handout provides information and follow-up instructions for persons who have been exposed to
formaldehyde or formalin.
What is formaldehyde?
Formaldehyde is a nearly colorless, highly irritating gas with a sharp odor. It dissolves easily in water
and is found in formalin (a solution of formaldehyde, water, and methanol). Formaldehyde is used in
the manufacture of plastics; urea-formaldehyde foam insulation; and resins used to make construction
materials (e.g., plywood), paper, carpets, textiles, paint, and furniture.
What immediate health effects can result from formaldehyde exposure?
Formaldehyde can cause irritation of the eyes, nose, and throat, even at low levels for short periods.
Longer exposure or higher doses can cause coughing or choking. Severe exposure can cause death from
throat swelling or from chemical burns to the lungs. Direct contact with the skin, eyes, or
gastrointestinal tract can cause serious burns. Drinking as little as 30 mL (about 2 tablespoons) of
formalin can cause death. Formate, a formaldehyde metabolite, can cause death or serious systemic
effects. Generally, the more serious the exposure to formaldehyde, the more severe the symptoms.
Previously sensitized persons may develop a skin rash or breathing problems from very small exposures.
Can formaldehyde poisoning be treated?
There is no antidote for formaldehyde, but its effects can be treated, and most exposed persons get well.
Patients who have had a serious exposure (with signs and symptoms such as tearing eyes, running nose,
or severe or persistent coughing) may need to be hospitalized. Patients with direct exposure to very
concentrated vapors or liquid or who have swallowed formalin may require intensive hospital treatment
and may experience long-term effects.
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 not occur for up to 18 hours. See Follow-up
Instructions for signs and symptoms to watch for. If any of them occur, seek medical care. Long-term,
repeated exposure to formaldehyde in the workplace may cause cancer of the nasal passages.
What tests can be done if a person has been exposed to formaldehyde?
Specific tests for the presence of formaldehyde in blood or urine may be available, but the results
generally are not useful to the doctor. If a severe exposure has occurred, blood and urine analyses and
other tests may show whether the lungs have been injured or if systemic effects are possible. If seizures
or convulsions have occurred neurobehavioral toxicity testing may be necessary. Testing is not needed
in every case.
Where can more information about formaldehyde be found?
More information about formaldehyde 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.
ATSDR • Patient Information Sheet 23