AMATS Air Quality Update April 2012 Municipality of Anchorage Department of Health and Human Services Status Report Carbon monoxide (CO) Particulate matter (PM10 & PM2.5) Ozone Airborne lead Air toxics (benzene) Sulfur dioxide, nitrogen dioxide CO Colorless odorless gas produced by incomplete combustion 79% of emissions from motor vehicles Highest concentrations occur on cold mid-winter days with strong temperature inversions Residential areas tend to have highest concentrations Anchorage CO Trend 30.0 2nd max 8-hr average (ppm) 25.0 20.0 15.0 CO NAAQS = 9 ppm 10.0 5.0 0.0 1980 1996 1985 1990 1995 2000 2005 2010 Comparison with CO Concentrations in Selected Western Cities in U.S. (2010) Highest 8-hour Concentration (ppm) 2nd Highest 8hour Concentration (ppm) Number of Exceedances of the NAAQS Anchorage, AK 6.9 6.1 0 Fairbanks, AK 5.0 4.1 0 Las Vegas, NV 3.4 3.0 0 Phoenix, AZ 3.3 3.2 0 El Paso, TX 3.3 2.8 0 Denver, CO 3.1 2.4 0 Ogden, UT 2.4 1.9 0 Reno, NV 2.4 2.1 0 Portland, OR 2.4 2.4 0 Spokane, WA 2.3 1.9 0 Salt Lake City, UT 2.2 1.9 0 Albuquerque, NM 2.0 2.0 0 Sacramento, CA 1.9 1.9 0 Seattle, WA 0.8 0.7 0 Metropolitan Area PM10 and PM2.5 Width of human hair PM10 (10µm) PM2.5 (2.5 µm) Linked with asthma and other respiratory health problems Death rates in hospitals increase when PM2.5 concentrations are high Anchorage studies show that there are more doctor visits for asthma when PM10 levels increase PM10 Occasional violations of the NAAQS in spring at Tudor Road site due to road dust. Magnesium chloride is being used to suppress dust along 40 miles of high volume roadways in Anchorage and Eagle River. Eagle River regularly violated NAAQS in late-1980’s before roads were paved Strong winds transported dust from glacial river valleys in Mat Su causing exceedances of NAAQS in 2003, 2007, 2009, and 2010. September 24, 2010 MODIS satellite image PM2.5 Generally low concentrations in Anchorage (ranked 6th cleanest city for year-round PM2.5 pollution by ALA) C14 analysis of Anchorage samples suggests that most PM2.5 is from wood smoke Assembly passed outdoor wood boiler ordinance restricting installations to those meeting EPA-certified Phase 2 standards. NESCAUM 2006 No obvious upward or downward trend in PM10 or PM2.5 during past 10 years PM10 PM10 NAAQS = 150 ug/m3 150 100 PM2.5 50 0 2001 2003 2005 2007 2009 2011 98th percentile (ug/m3) 2nd max (ug/m3) 200 40 PM2.5 NAAQS = 35 ug/m3 30 20 10 0 2001 2003 2005 2007 2009 2011 Ozone (O3) Secondary pollutant produced by a chemical reaction between oxides of nitrogen and volatile organic compounds in the presence of sunlight. Ozone in stratosphere protects us from UV Causes respiratory irritation, coughing, pain Highest concentrations seen downwind of major urban centers in summer O3 levels in Anchorage and Eagle River were among the lowest 1% of sites in U.S. Ozone is the main ingredient in “smog.” Airborne Lead EPA study of 15 mid-sized airports serving piston aircraft Unlike gasoline, aviation fuel still contains lead additive One-year study at Merrill Field will conclude Oct 2012 Will not be used to assess attainment with the new ambient lead standard Preliminary data suggest that concentrations at Merrill Field are below standard Air toxics (benzene) DHHS is monitoring ambient benzene to assess impact of new EPA limits on the amount of benzene in gasoline Phase 1 (completed) Phase 2 (planned) Oct 2008 – Oct 2009 Aug 2012 – Aug 2013 Gasoline benzene ≈ 5% Gasoline benzene <1.3% Found average ambient benzene levels at Garden site in Airport Heights to be in 98th percentile of U.S. sites How much will ambient benzene concentrations be reduced? Garden site (Anchorage) Annual Average [benzene] = 1.1 ppb Galena Park, TX (near Houston) Annual Average [benzene] = 1.1 ppb Summary CO has fallen dramatically and is expected to continue to decline, but more slowly than the past. PM10 is a problem during spring break up. Magnesium chloride is used to control dust on major roads. Unpaved road problem in Eagle River has been resolved. PM2.5 is fairly low but could pose a problem if wood burning increases. Ozone levels are among lowest in the U.S. Benzene concentrations were among highest in U.S. in 2008-09. The impact of lowering the gasoline benzene content from 5% to 1.3% or lower will be evaluated this coming year.