June 15, 2017

Air Quality – Breathers Beware

Summer is definitely here.  With the onset of warm weather, individuals with respiratory problems need to be aware of the increased risk of ground-level ozone and fine particle pollution (in combination, referred to as smog), and take health precautions when the levels are high.  High concentrations of fine particles in the air and ground-level ozone cause respiratory and cardiovascular problems, contributing to tens of thousands of premature deaths annually.  For many individuals – especially sensitive groups including children, the elderly, and those who suffer from asthma and other respiratory/cardiovascular problems -knowing forecast levels of pollution can make a significant difference in the quality of their lives and how they plan their daily activities.  Poor air quality affects everyone, but some people are particularly sensitive to air pollutants, including children and adults who are active outdoors, and people with respiratory diseases, such as asthma. When air quality is predicted to be unhealthy, the Environmental Protection Agency (EPA) and the states will announce an air quality alert for the affected areas. On those occasions it is recommended that people limit strenuous outdoor activity and citizens and businesses take actions that will help reduce air pollution and protect the public health.

Ground-level ozone and airborne particles are the two pollutants that pose the greatest threat to human health in this country.  Ozone is “good” or “bad” depending on its location in the atmosphere. In the upper atmosphere, “good” ozone is produced naturally and protects us from UV radiation.  At ground-level, “bad” ozone is a harmful air pollutant.  Ground level ozone peaks on hot summer days because of how it is formed: a chemical reaction between nitrogen oxides and volatile organic compounds (VOCs) in the presence of sunlight.  VOCs are emitted to the air from a variety of activities, including: Industrial and commercial activities, motor vehicle emissions and vehicle refueling, lawnmowers and other gas-powered devices, and household products, such as cleaners, paints, charcoal lighter fluid, etc.  Weather plays a key role in ozone formation. The highest ozone levels are usually recorded in summer months when temperatures approach the high 80s and 90s and the wind is stagnant or light.

At ground level, ozone is a health hazard for all of us, especially the young and elderly. Those who are active and exercising outdoors may experience breathing difficulties and eye irritation. Prolonged exposure may result in reduced resistance to lung infections and colds. Ozone can also trigger attacks and symptoms in individuals with pre-existing conditions, like asthma or other respiratory conditions like chronic bronchitis and COPD.  It has been estimated that even healthy adults can experience a 15-20% reduction in lung function from prolonged exposure to low levels of ozone.
Fine particulate pollution consists of fine solid or liquid particles from smoke, dust, and condensing vapors. Particulate matter is suspended and carried in the air for long periods and distances. Particulate pollution comes from a variety of sources, including dust stirred up from traveling on unpaved and paved roadways, construction activities, gas and diesel powered engines, wood burning, outdoor burning, wildfires, and industrial/commercial operations.

Air Quality Index (AQI)

The AQI is an index for reporting daily air quality. It tells you how clean or polluted your air is, and what associated health effects might be a concern for you. The AQI focuses on health effects you may experience within a few hours or days after breathing polluted air. The Environmental Protection Agency (EPA) calculates the AQI for five major air pollutants regulated by the Clean Air Act: ground-level ozone, particle pollution (particulate matter), carbon monoxide, sulfur dioxide, and nitrogen dioxide.  Think of the AQI as a yardstick that runs from 0 to 500.  The higher the AQI value, the greater the level of air pollution and the greater the health concern. For example, an AQI value of 50 represents good air quality with little potential to affect public health, while an AQI value over 300 represents hazardous air quality.  An AQI value of 100 generally corresponds to the national air quality standard for the pollutant, which is the level EPA has set to protect public health. AQI values below 100 are generally thought of as satisfactory. When AQI values are above 100, air quality is considered to be unhealthy-at first for certain sensitive groups of people, then for everyone as AQI values get higher.

What to do when ozone level/AQI is high

  • Limit outdoor activity
  • Exercise early in the morning or indoors
  • Pay attention to respiratory symptoms such as coughing, wheezing and discomfort, and see your doctor if necessary

Everyone can help reduce air pollution by taking the following steps:

  • Use public transportation or walk whenever possible
  • Combine errands and car-pool to reduce driving time and mileage
  • Use less electricity by turning air conditioning to a higher temperature setting, and turning off lights, TVs and computers when they are not being used
  • Avoid using other small gasoline-powered engines, such as lawn mowers, chain saws and leaf blowers on unhealthy air days.

For more information on air quality as well as to find the AQI in your area, follow these links: