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Particle Pollution and Your Patients' Health

Review Questions for Particle Pollution

  1. Smaller ambient air particles (< 10 μm) are more of a health concern than larger ambient air particles (> 10 μm).

 A. True 
 B. False 

  • Answer

    A. True. The EPA is concerned about ambient air particles that are 10 micrometers in diameter or smaller because these are the particles that generally pass through the throat and nose and enter the lungs and even the bloodstream. Larger particles (> 10 μm) are of less concern because they usually cannot enter the lungs, although they can still irritate the eyes, nose, and throat.

  1. People with heart disease can let their symptoms be their guide as to when to reduce exposure to particle pollution.

 A. True
 B. False 

  • Answer

    B. False. Symptoms are not a reliable indicator of whether particle pollution levels are unhealthy. There may be no immediate symptoms even at relatively high levels of exposure.  For people with heart disease, the first symptom could be a heart attack. The most reliable way to know if particle pollution levels may be unhealthy is to check the current air quality in your location at

  1. Clinically important health effects of inhaled particle pollution include:

 A. Acute coronary syndrome, including myocardial infarction and unstable angina
 B. Arrhythmia
 C. Exacerbation of chronic heart failure
 D. Stroke
 E. All of the above

  • Answer

    E. All of the above. All four clinical conditions are associated with exposure to inhaled particle pollution. An extensive body of scientific evidence shows that exposure to fine particles can cause cardiovascular effects, including heart attacks, heart failure, and strokes, which results in hospital admissions, emergency department visits, and, in some cases, premature death.

  1. The adverse health effects of inhaled particle pollution depend on:

 A. Inhaled dose
 B. Individual susceptibility
 C. Age
 D. A and B
 E. All of the above

  • Answer

    E. All of the above.  All of the above factors influence the inhaled amount of particle pollution and affect peripheral and central deposition of particle pollution, pathophysiologic responses, and ultimately health effects. 

  1. Which populations are at greater risk of particle pollution-related health effects than healthy young adults?

 A. People with respiratory disease (like asthma and COPD) 
 B. People with heart disease
 C. Older adults
 D. Children (less than 18)
 E. All of the above

  • Answer

    E. All of the above. Numerous epidemiological studies have reported evidence of increased risk of particle pollution-related health effects in children and older adults and exacerbation of disease in patients with pre-existing respiratory disease, such as asthma and COPD, or heart disease.

  1. Which of the following statements is false?

 A. Adults with respiratory disease are at increased risk of particle pollution-related health effects.
 B. Different people with pre-existing respiratory disease will have similar responses when exposed to the same concentration of particle pollution.
 C. Airway inflammation is a typical response to particle pollution exposure.
 D. There may be no immediate health symptoms of particle pollution exposure even at relatively high particle pollution concentrations.

  • Answer

    B is the false statement. There is great variability in individual responsiveness to particle pollution among both healthy and at-risk people. Some individuals may show no response while others will have a measurable reaction.

  1. The AQIHelpAir Quality Index (AQI) A nationally uniform index for reporting and forecasting daily air quality. It is used to report on the four most common ambient air pollutants that are regulated under the Clean Air Act: ground-level ozone, particle pollution (PM10 and PM2.5), carbon monoxide (CO), and sulfur dioxide (SO2). The AQI focuses on health effects that may be experienced within a few hours or days after breathing polluted air. health and cautionary statements are pollutant-specific, and they suggest relatively simple measures people can take to reduce their risk from exposure to air pollution.

 A. True 
 B. False 

  • Answer

    A. True. For example, when the AQI value for particle pollution is between 101 and 150, or Code Orange, air quality is considered “unhealthy for sensitive groups.” In this range, people with heart or lung disease, older adults, children, people with diabetes, and people of lower SES are advised to reduce prolonged or heavy exertion.

  1. Particle pollution levels can be high: 

 A. Any time of the year
 B. Near busy roadways
 C. During wildfires or dust storms
 D. All of the above

  • Answer

    D. All of the above. Particle pollution can occur year-round and can be especially high near busy roadways and during wildfires or dust storms.

  1. When particle pollution levels are unhealthy, the group(s) that should reduce exposure to particle pollution are: 

 A. People with heart or lung disease 
 B. Older adults
 C. Children (less than 18)
 D. Everyone

  • Answer

    D. Everyone. When air quality is in the unhealthy range (Code Red), everyone who is active outdoors may experience effects and should reduce exposure. Members of sensitive groups are likely to experience more serious effects.

  1. A one-strap paper mask or a surgical mask can provide adequate protection from wildfire smoke.  

 A. True 
 B. False

  • Answer

    B. False.  One-strap paper masks, surgical masks, or other face coverings are likely to provide far less or no protection compared to disposable N95 or P100 particulate respirators.  Respirators should be considered only after first implementing other, more effective methods of exposure reduction, including staying indoors, reducing activity, and using HEPA air cleaners indoors to reduce overall smoke exposure.