Medical Management Guidelines for Sulfur Dioxide
(SO2)
CAS#:  7446-09-5
UN#: 1079
PDF Versionpdf icon[178 KB]
                  Synonyms include sulfur oxide, sulfurous acid anhydride, sulfurous anhydride, and sulfurous oxide.
                                      
                  
                    - Persons exposed only to sulfur dioxide gas pose no risk 
                      of secondary contamination. Persons whose skin or clothing 
                      is contaminated with liquid sulfur dioxide can secondarily 
                      contaminate rescuers by direct contact or through off-gassing 
                      of vapor.
- At room temperature, sulfur dioxide is a nonflammable, 
                      colorless gas that is heavier than air. Its strong, pungent 
                      odor and irritating properties usually provide adequate 
                      warning of its presence.
- Sulfur dioxide is readily absorbed through the upper respiratory 
                      tract; no data were located regarding dermal absorption. 
                      Sulfur dioxide is present in some foods; therefore, oral 
                      ingestion, although insignificant, is possible.
 General Information
Description
                  At room temperature, sulfur dioxide is a nonflammable, colorless gas with a very strong, pungent odor. Most people can smell sulfur dioxide at levels of 0.3 to 1 ppm. It is handled and transported as a liquefied compressed gas. It easily dissolves in water. The liquid is heavier than water. Although sulfur dioxide does not burn in air, cylinders of compressed liquid can explode in the heat of a fire.
                  
Routes of Exposure
Inhalation
                  Inhalation is the major route of exposure 
                    to sulfur dioxide. The odor threshold is 5 times lower than 
                    the OSHA PEL (5 ppm). Most exposures are due to air pollution, 
                    and this has both short-term and chronic health consequences 
                    for people with lung disease. Inhaled sulfur dioxide readily 
                    reacts with the moisture of mucous membranes to form sulfurous 
                    acid (H2SO3), which is a severe irritant. 
                    People with asthma can experience increased airway resistance 
                    with sulfur dioxide concentrations of less than 0.1 ppm when 
                    exercising. Healthy adults experience increased airway resistance 
                    at 5 ppm, sneezing and coughing at 10 ppm, and bronchospasm 
                    at 20 ppm. Respiratory protection is required for exposures 
                    at or above 20 ppm. Exposures of 50 to 100 ppm may be tolerated 
                    for more than 30 to 60 minutes, but higher or longer exposures 
                    can cause death from airway obstruction. Sulfur dioxide is 
                    heavier than air; thus, exposure in poorly ventilated, enclosed, 
                    or low-lying areas can result in asphyxiation.
                   Children exposed to the same levels 
                    of sulfur dioxide as adults may receive a 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 sulfur 
                    dioxide found nearer to the ground and because they are slow 
                    to leave the site of an exposure. 
                
Skin/Eye Contact
                  Exposures of 10 to 20 ppm cause irritation 
                    to mucous membranes. Direct contact with escaping compressed 
                    gas or liquid sulfur dioxide can produce severe corneal damage 
                    and frostbite injury to the skin. No data were located regarding 
                    dermal absorption.
Ingestion
                  Ingestion of sulfur dioxide is unlikely 
                    because it is a gas at room temperature. Sulfur dioxide is 
                    used in small amounts as a food and wine preservative. Highly 
                    sensitive asthmatic individuals can develop bronchospasm after 
                    eating foods or drinking wine preserved with sulfur dioxide 
                    or other sulfur preservatives.
                    
Sources/Uses
                  Sulfur dioxide gas is released primarily 
                    from the combustion of fossil fuels (75% to 85% of the industrial 
                    sources), the smelting of sulfide ores, volcanic emissions, 
                    and several other natural sources. It is a U.S. Environmental 
                    Protection Agency (EPA) priority air pollutant, but has many 
                    industrial and agricultural uses. It is sometimes added as 
                    a warning marker and fire retardant to liquid grain fumigants. 
                    Approximately 300,000 tons are used each year to manufacture 
                    hydrosulfites and other sulfur-containing chemicals (40%); 
                    to bleach wood pulp and paper (20%); to process, disinfect, 
                    and bleach food (16%); for waste and water treatment (10%); 
                    in metal and ore refining (6%); and in oil refining (4%). 
                    Toxic amounts of sulfur dioxide can be released from the preservative 
                    chemical metabisulfite in the presence of water and acid.
Standards and Guidelines
                  OSHA PEL (permissible exposure limit) 
                    = 5 ppm (averaged over an 8-hour workshift)
                   NIOSH IDLH (immediately dangerous to 
                    life or health) = 100 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) = 
                    3 ppm
Physical Properties
                  Description: colorless gas at 
                    room temperature, colorless liquid when pressurized or cooled.
                  Warning properties: pungent odor 
                    is usually adequate to warn of acute exposure. Most people 
                    can detect sulfur dioxide at levels of 1 to 3 ppm (1 ppm is 
                    equivalent to 2.62 mg/m3).
                  Molecular weight: 64.06 daltons
                  Boiling point (760 mm Hg): 14.0°F 
                    (-10.0°C)
                  Freezing point: -99.4°F (-72.7°C)
                  Vapor pressure: 2,538 mm Hg at 
                    70.0EF (21.1°C)
                  Vapor density: 1.43 g/mL (water 
                    = 1.00)
                  Water solubility: soluble in water 
                    (11.3 g/100 mL at 68°F [20°C])
                  Flammability: nonflammable
                  
Incompatibilities
                  Sulfur dioxide dissolves in water or 
                    steam to form sulfurous acid. Liquid sulfur dioxide corrodes 
                    iron, brass, copper, and some forms of plastic and rubber. 
                    Many metals, including zinc, aluminum, cesium, and iron, incandesce 
                    and/or ignite in unheated sulfur dioxide. Sulfur dioxide reacts 
                    explosively when it comes in contact with sodium hydride. 
                    Sulfur dioxide ignites when it is mixed with lithium acetylene 
                    carbide diamino or lithium acetylide ammonia.
	
Health Effects
                  
                    - Sulfur dioxide is severely irritating to the eyes, mucous 
                      membranes, skin, and respiratory tract. Bronchospasm, pulmonary 
                      edema, pneumonitis, and acute airway obstruction can occur.
- Inhalation exposure to very low concentrations of sulfur 
                      dioxide can aggravate chronic pulmonary diseases, such as 
                      asthma and emphysema. Certain highly sensitive asthmatics 
                      may develop bronchospasm when exposed to sulfur dioxide 
                      or sulfite-preserved foods.
- Sulfur dioxide reacts with water in the upper airway to 
                      form hydrogen, bisulfite, and sulfite, all of which induce 
                      irritation. As a result, reflex bronchoconstriction increases 
                      airway resistance.
Acute Exposure
                  Sulfur dioxide dissolves in the moisture 
                    on skin, eyes, and mucous membranes to form sulfurous acid, 
                    an irritant and inhibitor of mucociliary transport. Most of 
                    the inhaled sulfur dioxide is detoxified by the liver to sulfates 
                    and excreted in the urine. The bisulfite ion produced when 
                    sulfur dioxide reacts with water is likely to be the main 
                    initiator of sulphur dioxide-induced bronchoconstriction.
                   Children do not always respond to chemicals 
                    in the same way that adults do. Different protocols for managing 
                    their care may be needed.
					
Respiratory
                  Sulfur dioxide respiratory irritation 
                    induces symptoms such as sneezing, sore throat, wheezing, 
                    shortness of breath, chest tightness, and a feeling of suffocation. 
                    Reflex laryngeal spasm and edema can cause acute airway obstruction. 
                    Bronchospasm, pneumonitis, and pulmonary edema can occur.
                   Some individuals are very susceptible 
                    to the presence of sulfur dioxide and overreact to concentrations 
                    which, in most people, elicit a much milder response. This 
                    hyperreactive response occurs the first time the individual 
                    is exposed and is therefore not an acquired immune or "hypersensitivity" 
                    response.
                   Acclimatization (a physiological adjustment 
                    of the individual to environmental changes) may also occur 
                    in up to 80% of exposed individuals. This is not necessarily 
                    beneficial although exposure may become less subjectively 
                    objectionable upon continuous or repeated exposure.
                   Asthmatics who are sensitive to sulfites 
                    in food can develop bronchospasm or an anaphylactoid reaction. 
                    Sulfur dioxide, along with other components of air pollution, 
                    can exacerbate chronic cardiopulmonary disease.
                   Exposure to high concentrations of sulfur 
                    dioxide 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 also may be more vulnerable because 
                    of relatively increased minute ventilation per kg and failure 
                    to evacuate an area promptly when exposed.
Dermal
                  Sulfur dioxide is a severe skin irritant 
                    causing stinging pain, redness, and blisters, especially on 
                    mucous membranes. Skin contact with escaping compressed gas 
                    or liquid sulfur dioxide can cause frostbite and irritation 
                    injury.
                   Because of their relatively larger surface 
                    area: body weight ratio, children are more vulnerable to toxicants 
                    that affect the skin.
                    
Ocular
                  Conjunctivitis and corneal burns can result from the irritant effect of sulfur dioxide vapor or escaping compressed gas, and from direct exposure to the liquid.
                
Gastrointestinal
                  Nausea, vomiting, and abdominal pain have been reported after inhalation exposure to moderate to high doses of sulfur dioxide.
					
Potential Sequelae
                  High-level acute exposures have resulted 
                    in pulmonary fibrosis, chronic bronchitis, and chemical bronchopneumonia 
                    with bronchiolitis obliterans. Bronchospasm can be triggered 
                    in individuals who have underlying lung disease, especially 
                    those who have asthma and emphysema. Rarely, new onset airway 
                    hyperreactivity, known as reactive airways dysfunction syndrome 
                    (RADS), develops in patients without prior bronchospasm.
                                
Chronic Exposure
 
                  Chronic exposure can result in an altered 
                    sense of smell (including increased tolerance to low levels 
                    of sulfur dioxide), increased susceptibility to respiratory 
                    infections, symptoms of chronic bronchitis, and accelerated 
                    decline in pulmonary function. Chronic exposure may be more 
                    serious for children because of their potential longer life 
                    span.
                    
Carcinogenicity
 
                  The International Agency for Research 
                    on Cancer (IARC) assigned sulfur dioxide to Group 3, not classifiable 
                    as to its carcinogenicity to humans.
Reproductive and Developmental Effects
 
                  Sulfur dioxide 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. There are no known reproductive 
                    or developmental effects of sulfur dioxide alone by any route 
                    of exposure. There is no conclusive evidence that sulfur dioxide 
                    is a genotoxin in humans. 
                
 Prehospital Management
                  
                    - Persons exposed only to sulfur dioxide gas pose no risk 
                      of secondary contamination to rescuers. Persons whose skin 
                      or clothing is contaminated with liquid sulfur dioxide can 
                      secondarily contaminate response personnel by direct contact 
                      or through off-gassing of vapor.
- Sulfur dioxide is severely irritating to the eyes, mucous 
                      membranes, skin, and respiratory tract. Exposure to high 
                      levels can cause pulmonary edema, bronchial inflammation 
                      and laryngeal spasm and edema with possible airway obstruction.
- There is no antidote for sulfur dioxide. 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 the rescuers have not been trained 
                    in its use, call for assistance from a local or regional hazardous 
                    materials (HAZMAT) team or other properly equipped response 
                    organization.
                    
Rescuer Protection
                  Inhaled sulfur dioxide vapor is readily 
                    absorbed and is a potent respiratory tract irritant, causing 
                    mild irritation even at low doses. Escaping compressed gas 
                    or liquid sulfur dioxide on the skin or eyes can cause frostbite 
                    injury and irritation. Dermal absorption is negligible.
                   Respiratory Protection: Positive-pressure, 
                    self-contained breathing apparatus (SCBA) is recommended in 
                    response situations that involve exposure to potentially unsafe 
                    levels of sulfur dioxide gas.
                   Skin Protection: Fully encapsulated 
                    chemical-protective clothing is recommended because sulfur 
                    dioxide can cause skin irritation and burns.
ABC Reminders
                  Quickly access for a patent airway, ensure 
                    adequate respiration and pulse. Maintain adequate circulation. 
                    Provide supplemental oxygen if cardiopulmonary compromise 
                    is suspected. If trauma is suspected, manually maintain cervical 
                    immobilization and apply a cervical collar and a backboard 
                    when feasible. Apply direct pressure to stop any heavy bleeding.
Victim Removal
                  If victims can walk, lead them out of 
                    the Hot Zone to the Decontamination Zone. Victims who are 
                    unable to walk should 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
                  Patients exposed only to sulfur dioxide 
                    gas who have no eye or skin irritation do not need decontamination. 
                    They 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 required in the Hot 
                    Zone (described above).
                    
ABC Reminders
                  Quickly access for a patent airway, ensure 
                    adequate respiration and pulse. Maintain adequate circulation. 
                    Provide supplemental oxygen if cardiopulmonary compromise 
                    is suspected. If trauma is suspected, manually maintain cervical 
                    immobilization and apply a cervical collar and a backboard 
                    when feasible. Administer supplemental oxygen as required. 
                    Assist ventilation with a bag-valve-mask device if necessary. 
                    Apply direct pressure to control any heavy bleeding.
Basic Decontamination
                  Rapid skin decontamination is critical. 
                    Victims who are able may assist with their own decontamination. 
                    Remove contaminated clothing and personal belongings and place 
                    them in double plastic bags.
                  Gently wash exposed skin and hair with 
                    copious amounts of water (preferably under a shower). Use 
                    caution to avoid hypothermia when decontaminating children 
                    or the elderly. Use blankets or warmers when appropriate.
                  Irrigate exposed eyes with plain water 
                    or saline for at least 5 minutes. Remove contact lenses 
                    if they are easily removable without additional trauma to 
                    the eye. 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. 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). Victims 
                    who have undergone decontamination or have been exposed only 
                    to sulfur dioxide gas pose no serious risk of secondary contamination 
                    to rescuers. In such cases, Support Zone personnel require 
                    no specialized protective gear.
					
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 and establish intravenous access if necessary. 
                    Place on a cardiac monitor.
					
Additional Decontamination
                  Continue irrigating exposed skin and 
                    eyes, as appropriate. 
Advanced Treatment
                  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). Sulfur dioxide 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 having seizures or cardiac arrhythmias should be treated 
                    according to advanced life support (ALS) protocols.
                   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. 
					
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 the condition of the patient, 
                    treatment given, and estimated time of arrival at the medical 
                    facility to the base station and the receiving 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 have histories or evidence 
                    suggesting significant exposure (e.g., severe or persistent 
                    cough or dyspnea, or chemical burns) should be transported 
                    to a medical facility for evaluation. Patients who have a 
                    history of chronic pulmonary disease should be clinically 
                    evaluated for airflow obstruction.
                  Patients who have symptoms of mild or 
                    transient skin, nose, or eye irritation may be discharged 
                    from the scene after their names, addresses, and telephone 
                    numbers are recorded. They should be advised to rest and to 
                    seek medical care promptly if symptoms develop or recur (see 
                    Patient Information Sheet below).
	
 Emergency Department Management
 
                  
                    - Persons exposed only to sulfur dioxide gas pose no risk 
                      of secondary contamination to rescuers. Persons whose skin 
                      or clothing is contaminated with liquid sulfur dioxide can 
                      secondarily contaminate response personnel by direct contact 
                      or through off-gassing of vapor.
- Sulfur dioxide is a severe irritant to the respiratory 
                      tract, eyes, mucous membranes, and skin. Exposure to high 
                      doses can cause pulmonary edema, bronchial inflammation, 
                      and laryngeal spasm and edema with possible airway obstruction.
- There is no antidote for sulfur dioxide. Treatment consists 
                      of support of respiratory and cardiovascular functions.
Decontamination Area
                  Previously decontaminated patients and 
                    those exposed only to sulfur dioxide gas who have no skin 
                    or eye irritation may be transferred immediately to the Critical 
                    Care Area. Others 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.
                   Emergency room personnel should examine 
                    children's mouth because of the frequency of hand-to-mouth 
                    activity among children.
                
ABC Reminders
                  Evaluate and support the airways, breathing, 
                    and circulation. Children may be more vulnerable to corrosive 
                    agents than adults because of the relatively smaller diameter 
                    of their airways. Provide supplemental oxygen if cardiopulmonary 
                    compromise is suspected. 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 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). Sulfur dioxide 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 are having seizures or cardiac arrhythmias should be treated 
                    in the conventional manner.
Basic Decontamination
                  Patients who are able may assist with 
                    their own decontamination.
                  Because sulfur dioxide can 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. After 
                    the patient has been decontaminated, no special protective 
                    clothing or equipment is required for ED personnel.
                  Quickly remove contaminated clothing 
                    while gently washing the skin with water (preferably under 
                    a shower). Double-bag the contaminated clothing and personal 
                    belongings. Sulfur dioxide reacts with body moisture to form 
                    sulfurous and sulfuric acids; therefore, chemical burns are 
                    likely. Handle burned skin with caution.
                  Flush exposed or irritated eyes with 
                    plain water or saline for at least 5 minutes. Remove 
                    contact lenses if easily removable without additional trauma 
                    to the eye. If pain or injury is evident, continue irrigation 
                    while transferring the victim to the Critical Care Area. An 
                    ophthalmic anesthetic, such as 0.5% tetracaine, might be necessary 
                    to alleviate blepharospasm, and lid retractors might be required 
                    to allow adequate irrigation under the eyelids.
Critical Care Area
                  Be certain that appropriate decontamination 
                    has been carried out (see Decontamination Area, above).
ABC Reminders
                  Evaluate and support the airways, 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. Continuously 
                    monitor cardiac rhythm.
                  Patients who are comatose, hypotensive, 
                    or are having seizures or cardiac arrhythmias should be treated 
                    in the conventional manner.
                    
Inhalation Exposure
                  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). Sulfur 
                    dioxide 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.
                  Use of steroids to prevent or treat chemical 
                    pneumonitis and pulmonary edema is controversial. Antibiotics 
                    should be used as indicated to control infection. Damaged 
                    lower respiratory tissue might be more susceptible to infection.
Skin Exposure
                  Escaping compressed gas or liquid sulfur 
                    dioxide can cause frostbite. If frostbite is present, treat 
                    affected areas by rewarming in a water bath at a temperature 
                    of 104 to 107.6°F (40 to 42°C) for 20 to 30 minutes 
                    and continue until a flush has returned to the affected area. 
                    If chemical burns are present, treat as thermal burns.
                   Because of their relatively larger surface 
                    area:body weight ratio, children are more vulnerable to toxicants 
                    that affect the skin.
Eye Exposure
                  Continue irrigation for at least 15 minutes 
                    or until the pH of the conjunctival fluid has returned to 
                    normal. Test visual acuity. Examine the eyes for conjunctival 
                    or corneal damage and treat appropriately. Immediately consult 
                    an ophthalmologist for patients who have suspected severe 
                    corneal injuries.
Antidotes and Other Treatments
                  There is no antidote for sulfur dioxide. 
                    Treatment is supportive of respiratory function.
					
Laboratory Tests
					
                  Routine laboratory studies include chest 
                    radiography and pulse oximetry (or ABG measurements).
Disposition and Follow-up
                  Consider hospitalizing symptomatic patients 
                    who have evidence of respiratory distress or significant skin 
                    burns.
                  Pulmonary injury might continue to evolve 
                    over 18 to 24 hours. Patients exposed by inhalation who are 
                    initially symptomatic should be observed carefully and reexamined 
                    periodically. Patients who develop pulmonary edema should 
                    be admitted to an intensive care unit.
                    
Delayed Effects
                  Reactive airways dysfunction syndrome 
                    (RADS) is a non-immune-mediated asthma-like syndrome that 
                    can develop after exposure to sulfur dioxide. Once established, 
                    this non-specific bronchial hyperreactivity might diminish 
                    over a few weeks or persist for years. Bronchospasm might 
                    be triggered in people who have chronic pulmonary diseases, 
                    such as asthma and emphysema.
Patient Release
                  Patients who become totally asymptomatic 
                    in terms of pulmonary complaints in a 6- to 8-hour observation 
                    period are not likely to develop complications. They may be 
                    released and advised to rest and to seek medical care promptly 
                    if symptoms develop (see the Sulfur Dioxide-Patient Information 
                    Sheet below). Cigarette smoking can exacerbate pulmonary 
                    injury and should be discouraged for 72 hours after exposure.
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.
                   Follow-up evaluation of respiratory 
                    function should be arranged for severely exposed patients. 
                    Patients who have skin or corneal lesions should be reexamined 
                    within 24 hours.
Reporting
                  If a work-related incident has occurred, 
                    you might be legally required to file a report; contact your 
                    state or local health department.
                  Other persons might still be at risk 
                    in the setting where this incident occurred. If the incident 
                    occurred in the workplace, discussing it with company personnel 
                    might 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 form the Occupational 
                    Safety and Health Administration (OSHA) or the National Institute 
                    for Occupational Safety and Health (NIOSH).
	
 Patient Information Sheet 
 
                  This handout provides information and 
                    follow-up instructions for persons who have been exposed to 
                    sulfur dioxide. 
                    
                    Print this handout only.pdf icon[52.8 KB]
What is sulfur dioxide?
                  Sulfur dioxide is a colorless gas that 
                    has a strong, stinging odor. It has many industrial and agricultural 
                    uses. Most sulfur dioxide comes from burning fossil fuels 
                    containing sulfur and is a major part of air pollution. It 
                    is shipped and handled as a compressed gas in a special container. 
                    Some foods and wines are preserved with small amounts of sulfur 
                    dioxide that are safe for most people.
What immediate health effects can be caused by exposure to sulfur dioxide?
                  Inhaling sulfur dioxide causes irritation 
                    to the nose, eyes, throat, and lungs. Typical symptoms include 
                    sore throat, runny nose, burning eyes, and cough. Inhaling 
                    high levels can cause swollen lungs and difficulty breathing. 
                    Skin contact with sulfur dioxide vapor can cause irritation 
                    or burns. Liquid sulfur dioxide is very cold and can severely 
                    injure the eyes or cause frostbite if it touches the skin. 
                    Some people with asthma who are sensitive to sulfites might 
                    have an asthma attack if they eat foods preserved with sulfur 
                    dioxide or other sulfur-containing chemicals.
Can sulfur dioxide poisoning be treated?
                  There is no antidote for sulfur dioxide, 
                    but its effects can be treated and most exposed persons recover 
                    completely. Persons who have inhaled large amounts of sulfur 
                    dioxide might 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 serious exposure, damage to the 
                    lungs can occur, causing asthma, pneumonia, and bronchitis. 
                    Permanent damage to the lungs is possible.
What tests can be done if a person has been exposed to sulfur dioxide?
                  Specific tests for the presence of sulfur 
                    dioxide in blood or urine are not generally useful. If a severe 
                    exposure has occurred, blood analyses, x-rays, and breathing 
                    tests might show whether the lungs have been injured. Testing 
                    is not needed in every case.
                
 Where can more information about sulfur dioxide be found?
                  If the exposure happened at work, you 
                    might be required to contact your employer and the Occupational 
                    Safety and Health Administration (OSHA).
                  Employees may request a Health Hazard 
                    Evaluation from the National Institute for Occupational Safety 
                    and health (NIOSH).
                  More information about sulfur dioxide 
                    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. Ask the person who gave you this 
                    form for help 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[52.8 KB]
                  [ ] Call your doctor or the Emergency 
                    Department if you develop any unusual signs or symptoms within 
                    the next 24 hours, especially: 
                  
                    -  eye, nose, throat irritation
- coughing or wheezing
- difficulty breathing or shortness of breath
- chest pain or tightness
- nausea, vomiting, diarrhea, or stomach pain
[ ] 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.