September 16, 2001 

Contact: HHS Press Office (202) 690-6343


This fact sheet describes possible health hazards posed by the dust and debris from the World Trade Center’s (WTC) burning and collapse.  The most immediate hazards to health and well-being are from unstable buildings, broken glass, jagged metal and other harmful things.

What is in the dust?

Dust is a mixture of very fine particles that originally made-up the materials of the WTC and the aircraft that struck it.  These particles differ depending on what material the dust came from, how the dust was created, and what happened to the dust after it was released.  Analysis of dust samples will provide information on components of the dust. We expect that materials that would be present would be at concentrations lower than those normally associated with health effects.

Can the dust in the air cause illness soon after breathing it?

Intense exposure to dust and smoke causes eye, nose, throat, and lung irritation, triggering coughing and sneezing.  These short-term symptoms are the body’s way of removing foreign material.  Severe reactions usually occur in the first day or so after a high-level exposure and include persistent shortness of breath, rapid breathing, chest pain or tightness, headache, dizziness, or fainting.  Individuals with asthma, other lung conditions, or heart disease may be more vulnerable to the effects of dust and smoke.

Are there any long-term health effects from breathing smoke or dust?

Short duration, high intensity exposures to dust and smoke are more likely to result in short term and reversible effects.  Most dust-induced eye, nose, throat, and lung irritation does not result in long-term health effects.  Asthma and symptoms like wheezing and difficulty breathing are occasionally caused by exposure to a high dose of an irritant.  Chronic cough, with phlegm production, and/or shortness of breath can also occasionally occur.  Any person who develops asthma, wheezing, shortness-of-breath, chest pain, or fever should see a doctor.

What are the health threats to persons returning to the areas affected by dust and debris?

Persons entering areas covered with dust and debris may wish to avoid prolonged exposure.  Individuals entering these areas should avoid inhaling the dust or entering visibly dusty areas.  Avoid dry sweeping of dust and other dust-clearing procedures that disturb settled dust.  A limited dampening of settled dust with a fine water mist can markedly reduce the amount of dust that is raised during clean up.  Be careful – since excessive wetting may create a slip and fall hazard.  Slip-resistant shoes or boots may be helpful.  People who have been covered in dust that potentially contains asbestos should avoid taking the dust into their cars or homes (on clothes, skin, and hair), where others might be exposed.  It is best to remove dusty clothing while wearing respiratory protection.  A person should then shower completely and change into fresh clothing before going home.  Dusty clothing should be handled without shaking, and should be placed in bags.  Potentially contaminated clothing should be laundered separately.

Are masks useful for reducing exposure to dust and smoke?

Use of protective dust masks and dust-filtering respirators can effectively remove dust from inhaled air.  For those working in dusty areas, exposure can be reduced by wearing well-fitted dust masks (such as N-95 or more protective NIOSH-approved respirators available commercially.)  A poor fit can allow dust to bypass the dust filter, sharply reducing the effectiveness of the mask.  These dust-filtering masks are only effective against dust and provide no protection against toxic fumes or suffocation from lack of air.  Firefighters and other emergency responders with potential for intense exposures often need air-supplied respirators for such special situations.

What are other protective measures?

What should an individual do if they think they are affected from breathing the dust?

It is not necessary to visit an emergency room or physician for minor conditions such as eye irritation, coughing, or sneezing.  However, for persistent or more serious symptoms such as shortness of breath, chest pain or discomfort, or light-headedness, medical care is advised.  This is particularly true for individuals with pre-existing lung or heart conditions.

Who can be contacted for further information?

For health problems that may be due to the dust, a doctor should be consulted.  Doctors can contact public health officials to get information and advice on dealing with the hazards of the dust.

Follow the advice being given by local and state health officials about any steps that should be taken to safely re-enter a workplace or home.

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