News Release

For Immediate Release                                        

Contact:     Beth Gorman    (520) 740-3343

Tucson, Arizona (October 28, 2003) – When compared with 2001 and 2002, there were fewer days categorized as “good” and more days in the “moderate” category this summer, according to data from Pima County Department of Environmental Quality. For the last three years, the number of good air quality days has declined each year. Overall, during the summer of 2003, there were 5 days when air pollution levels were categorized as unhealthy for sensitive groups.

“When mixed with certain emissions, the long summer days with lots of heat and sunshine create higher levels of ground-level ozone,” said Beth Gorman, Program Manager for Pima County Department of Environmental Quality. “As fall begins, the sun’s intensity decreases along with ozone pollution levels,” she continued. Ground-level ozone is created when nitrogen oxides, typically from automobile emissions, combine with volatile organic compounds, such as solvents and gasoline fumes, in the presence of sunlight and heat. This air pollutant that forms at ground-level is not to be confused with the ozone layer that occurs naturally in the upper atmosphere and protects us from damaging solar radiation.

Changes in levels of solar radiation reduce the potential for ozone pollution, but fall and winter weather conditions can increase levels of two other pollutants in our air: particulate matter and carbon monoxide. “During the winter, cool, stagnant morning air traps pollutants close to the ground and often causes the ‘brown cloud’ to be more visible across our valley,” said Gorman. 

These more visible pollutants include particulate matter, which are microscopic particles generated from multiple sources including diesel soot, vehicle emissions, road dust from traffic, unpaved roads, industrial emissions, wood smoke, construction activities, farming, and wind-blown soil.

The Pima County area violated the Environmental Protection Agency (EPA) health standards for particulate matter that is 10 microns or less in diameter in 1999, which was a year with unusually dry and windy conditions. PDEQ is addressing this violation through the Natural Events Action Plan to reduce future particulate emissions. The Pima County Board of Supervisors adopted stricter dust control regulations in December 2002. There are now four full-time dust control inspectors at PDEQ to enforce the stricter regulations and a public education coordinator to increase awareness of health issues associated with elevated particulate.

The time for elevated levels of carbon monoxide (CO) also occurs in the winter, when stagnant weather conditions, coupled with reduced engine efficiency associated with cold temperatures, cause higher levels of CO. Other sources of CO include wood fires, barbeques, and gasoline lawn and garden equipment. After being designated as non-attainment of the EPA health standards for violations occurring in the 1970s and early 1980s, Pima County was redesignated by EPA as a CO maintenance area in the spring of 1999. “We need to maintain the programs that we have throughout Pima County such as oxygenated fuel, the Travel Reduction Program, the Clean Air Program, the emissions testing program, along with our air quality monitoring to make sure CO levels continue to stay at healthy levels,” said Wayne Byrd, Program Manager for PDEQ’s Air Quality Monitoring Division.

PDEQ is Air Quality Control District and, as such, is the agency responsible for ambient air monitoring in Pima County. The department monitors five different air pollutants at numerous sites around the county. Site-specific air pollution information can be obtained by calling (520) 882-4AIR or by visiting the PDEQ website at www.AirInfoNow.org.

Air Quality Index Readings
April 1 - September 30

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0 to 50 Good - No health effects are expected.

51 to 100 Moderate - Individuals may experience respiratory effects from prolonged outdoor exertion if they are unusually sensitive.

101 to 150 Unhealthy for Sensitive Groups - Members of sensitive groups may experience respiratory symptoms (coughing, pains when taking a deep breath).

151 to 200 Unhealthy - Members of sensitive groups have higher chance of experiencing respiratory symptoms (aggravated cough or pain), and reduces lung function. Everyone else should limit prolonged exertion.

201 to 300 Very Unhealthy - Members of sensitive groups experience increasingly severe respiratory symptoms and impaired breathing and should avoid any outdoor activity. Everyone else should limit prolonged exertion.

When inhaled, particulate matter invades the respiratory system’s natural defenses and lodges deep in the bronchial tubes. Health effects of particulate matter include:

· Premature mortality;

· Chronic respiratory disease;

· Aggravated asthma;

· Acute respiratory symptoms;

· Decreased lung function;

· Reduction in the body’s ability to fight infections.

· 36% increase in death from lung cancer;

· 26% increase in cardiopulmonary deaths;

· Significant increase in hospital and doctors visits; medication use;

· Increase in bronchitis, chronic cough, and respiratory symptoms in persons with COPD; and

· Increase in wheezing and shortness of breath

· Increase in cardio-respiratory mortality and morbidity even when PM is below federal standard

Carbon monoxide enters the bloodstream and reduces oxygen delivery to the body's organs and tissues. The health threat from exposure to CO is most serious for those who suffer from cardiovascular disease. Depending on the concentration level, health effects of CO include:

· Visual impairment;

· Reduced work capacity;

· Reduced manual dexterity;

· Poor learning ability difficulty in performing complex tasks;

· Fatigue in healthy people;

· Chest pain in people with heart disease;

· Headaches;

· Dizziness;

· Confusion;

· Nausea;

· Flu-like symptoms that clear up after leaving area with elevated CO; and

· Death.

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