National air quality has improved since the early 1990's, but many challenges remain in protecting public health and the environment from air quality problems. Since the 1950s, air quality has been a major public health and environmental concern. Local, state, and national programs have helped us learn more about the problems and how to solve them. NH EPHT Program works closely with NH Department of Environmental Services, the Centers for Disease Control and Prevention (CDC), and the U.S. Environmental Protection Agency (EPA) to track air quality data and to better understand how air pollution affects our health.

Air Pollution and Your Health
Air pollution in the United States poses a public health threat affecting potentially millions of people throughout the country. It is associated with health problems that include increased emergency department visits and hospitals stays for breathing and heart problems, asthma, and increases in illnesses such as pneumonia and bronchitis, and adverse reproductive outcomes such as low birth weight.

Air pollution comes from two main origins: point-sources (factories, construction, houses, businesses, agriculture) and non-point sources (automobiles, trains, buses, vegetation). The EPA lists the most common air pollutants as ground-level ozone, particle pollution (often referred to as particulate matter), nitrogen oxides, sulfur oxides, carbon monoxide, and lead.

Ozone (O3) and fine particulate matter (PM2.5) are the primary pollutants of concern in New Hampshire as they regularly occur at concentrations which can cause harmful health effects. Other contaminants, such as nitrogen-oxides and sulfur-dioxide, occasionally occur at significant concentrations.

Ground level ozone
Ozone is created indirectly when nitrogen oxides and volatile organic compounds mix in the presence of heat and sunlight. Your exposure to ozone depends mainly on where you live and work and how much time you spend outside. Everyone can have health problems from ozone. Symptoms might be very mild or more serious. People with lung disease, children, older adults, and people who are active outdoors are at the highest risk of having problems when ozone levels are unhealthy.

Many scientific studies have linked ground-level ozone contact to varied problems, such as

• lung and throat irritation,
• wheezing and breathing difficulties during exercise or outdoor activities,
• coughing and pain when taking a deep breath,
• aggravation of asthma, bronchitis, and emphysema, and
• higher chance of getting respiratory illness such as pneumonia or bronchitis.

Particulate Matter
Particle pollution, or particulate matter, consists of particles that are in the air, including dust, dirt, soot and smoke, and little drops of liquid. Fine particulates occur from being directly emitted (e.g., from a smokestack or tailpipe) or from secondary reactions in the air (e.g., when water vapor condenses on sulfate ions, which is also a secondary product of combustion). Some particles, such as soot or smoke, are large or dark enough to be seen. Other particles are so small that you cannot see them. Small particles are the most concerning because they are most likely to cause health problems. Their small size allows these particles to get into the deep part of your lungs. Being exposed to any kind of particulate matter may cause:

• increased emergency department visits and hospital stays for breathing and heart problems,
• breathing problems,
• asthma symptoms to get worse,
• adverse birth outcomes, such as low birth weight,
• decreased lung growth in children,
• lung cancer, and
• early deaths.

Sensitive people, including older adults, people with diseases such as asthma or congestive heart disease, and children, are more likely to be affected by contact with PM2.5.

Reduce Your Risk
EPA's Air Quality Index, or AQI, is a tool to help you quickly learn when air pollution is likely to reach unhealthy levels. Local TV stations, radio programs, and newspapers carry these air quality forecasts to tell you when particle levels are likely to be unhealthy. You can use the AQI to plan your daily activities to reduce exposure to particle pollution.

When particle pollution levels are high, you can:

• reduce the amount of time you spend outside;
• do easier outdoor activities, such as walking instead of running or using a riding lawn mower instead of a push mower; and
• exercise away from roads and highways. Particle pollution is usually worse near these areas.

If you have one of the following diseases, you may experience some effects from particle pollution:

• Lung disease
  • You may not be able to breathe as deeply or strongly as you usually do.
  • You may cough more, have chest pain, wheeze, feel like you can’t catch your breath, or be tired more than usual.
• Heart disease
  • Coming in contact with particle pollution can cause serious problems in a short period of time, such as a heart attack without any warning signs.
  • Symptoms, including chest pain or tightness, fast heartbeat, feeling out of breath, and feeling tired more than usual, may be signs of a serious problem. If you have any of these signs, follow your doctor's advice and contact your doctor if the symptoms last longer than usual or worsen.
• Asthma
  • Follow your asthma management plan when particle levels are high.

Tracking Air Pollution
Tracking air pollution can help people understand how often they are exposed to unhealthy levels of air pollution. Having these data can also help public health professionals or policymakers understand which areas may be most in need of prevention and control activities.

NH EPHT is tracking the following indicators about ozone and PM2.5:

• Ozone--Days Above Regulatory Standard
  The number of days in which the daily maximum 8-hour average ozone concentration exceeds a standard provides an indication of short-term spikes in ozone concentrations. This may give you an idea of how many days per year you may be exposed to unhealthy levels of ozone.

• PM2.5--Days Above Regulatory Standard
  These data help summarize short-term trends in particle pollution concentrations. This may give you an idea of how many days per year you may be exposed to unhealthy levels of particulate matter.

• Annual PM2.5 Level
  These data help summarize long-term trends in particle pollution concentrations. This will give you an idea of what the yearly level of PM2.5 is in an area.

Data about these indicators of air pollution are available on the Environmental Health Data Integration Network (EHDIN).

For information about specific health risks associated with ozone and particulate matter:

• Ozone
• Particulate matter

To read more about air contaminants:

• EPA Six Common Air Contaminants

To read more about air pollution and health:

• CDC Air Quality
• CDC Air Pollution and Respiratory Health
• Agency for Toxic Substances and Disease Registry (ATSDR) Air Information