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Smoggy Schools
April 20, 2005

Smoggy Schools: Intro: Proposed Protective Standard

California has the worst and most widespread ozone pollution in the United States. Seven metropolitan areas —Los Angeles, Visalia-Porterville, Bakersfield, Fresno, Merced, Sacramento and Hanford—rank among the ten smoggiest in the country. [American Lung Association 2004] Preliminary data from 2004 indicate that the San Joaquin Valley and the Los Angeles region both violated the current hourly ozone standard — no more than 90 parts per billion (ppb) in outdoor air — on more than 100 days in 2004. [ARB(1) 2005]

While ozone is vital in the upper atmosphere, ozone at the ground level is an unwanted air pollutant, commonly known as smog. Ozone is a powerful respiratory irritant. It can increase airway hyper-reactivity and airway inflammation, two triggers of asthma in sensitive individuals. It also increases symptoms of respiratory illness in people who are otherwise healthy. Ozone irritates lung passages and causes chest tightness, coughing, wheezing and shortness of breath.

Asthmatics and children are more sensitive to the harmful effects of ozone than healthy adults. [Scannell 1996, McBride 1994] Most asthmatics already suffer from chronic lung tissue inflammation. One in 10 California asthmatics have respiratory symptoms daily, and they experience a heightened response to ozone pollution compared to healthy individuals. [UCLA 2003] When smog levels rise asthmatics use more medication, have more respiratory illnesses, and visit the doctor, emergency room or hospital more frequently.

Both the prevalence and the severity of asthma have increased dramatically since the 1980s without a clear explanation. The rate of asthma and intensity of symptoms are both much higher in poorer families and for people of color. Therefore air pollution creates environmental inequity as some groups suffer disproportionately from the effects of ozone and other air pollutants.

Medications and efforts to reduce exposure to allergens that trigger asthma attacks can help stabilize many patients. But unlike interventions that burden families stricken by asthma—requiring them to keep their children indoors and pay for costly medication or improvement to their homes—improvements to air quality are permanent, economical, benefit everyone, and place the burden of change on polluters rather than California's families.

In addition to asthmatics, adults with other lung or heart disease, and people who work or exercise outdoors are at heightened risk for the ill effects of ozone pollution. [ARB(1) 2005] One in eight Californians have been diagnosed with asthma [UCLA 2003] and almost one in four adults have heart disease, meaning that a large portion of the state's residents find themselves in this 'high-risk' group.

A bold proposal to strengthen California's ozone standards

In addition to complying with federal smog rules, California has the authority to set its own standards for ozone. The current state rules require that the highest hourly concentration of smog on any given day not exceed 90 ppb, while the daily (maximum 8-hour) average should not exceed the federal standard of 80 ppb. In 1999, the California Legislature passed SB25 (Escutia), a groundbreaking law that obliged state scientists to assess air quality standards in light of new evidence of the effect of air pollution on children. [California Senate 1999]

The law charged the state with determining whether or not existing standards for hazardous air pollutants adequately protect children's health, and revising the standards that failed to do so. In 2002, after reviewing and tightening standards for airborne soot and dust, or particulate matter, ARB scientists turned their attention to smog. Following an exhaustive review, they reported substantial evidence that the existing ozone standard must be strengthened in order to fully protect children from smog, by adding a daily standard to the existing hourly standard.

Regulators determined that daily concentrations of 80 ppb were associated with lung function decrements, increased respiratory symptoms, increased airway reactivity and inflammation in healthy adults. They added an additional margin of safety to account for unusual vulnerability of children and people with lung disease, and proposed that smog measurement should not exceed an average value of 70 ppb over any 8-hour period.

The proposed California standard tightens up some administrative aspects of smog regulation. Both the current state hourly, and federal daily standards grant leeway for measurement that are within 5 parts per billion of the standard, meaning that a day is not in violation with the standard unless smog levels average 95 ppb for an hour or 85 ppb for an 8-hour period. The Federal standard also allows three violation days per year, and averages measurements over a three-year period. Neither of these practices are included in the proposed standard.

The proposed new standards would not trigger a regulatory crackdown — far from it. California smog and soot standards are meant to define clean air. They set a goal that the state's regional and local air districts are obliged to make steady progress toward them 'as expeditiously as possible.' The proposed new standards are a modest but essential step toward air that is better for the state's people and its economy.

California air quality routinely violates state and federal smog standards


  Daily standard (maximum 8-hr average) Hourly standard (maximum hour of day)
Ozone Standard 70 ppb 80 (85#) ppb 90 (95#) ppb
Regulatory agency Proposed California Current Federal* Current California
Proportion of counties with an air quality monitor that exceeded the air standard at least once between 2000-2003 92% 70% 76%

# while the standards are set at 80 and 90 ppb, smog levels are not considered to be a violation until they exceed 85 or 95 ppb.

* The current national daily standard is currently being reevaluated by EPA.

Forty of California's 58 counties have been declared to be out of compliance with California's one-hour ozone standard of 90 ppb. Health officials estimate that 84 percent of the state's population, or 30 million people, live in areas where peak ozone levels exceed the current hourly guidelines during some part of the year. [ARB(1) 2005] However, the proposed daily ozone standard is tougher. Between 2000 and 2003, almost 80 percent of the state's ozone monitors reported at least one violation of the hourly ozone standard and 92 percent violated the proposed daily standard. [ARB(2) 2005]

The California "ozone season" runs from May to September. During the 2000-2003 period seven counties—Fresno, Tulare, Merced, Kern, Riverside, San Bernardino and Kings—violated the proposed daily smog standard on about half of all days during this period. These counties also violated the hourly smog standard on 25 percent to 35 percent of the days in smog season. Complete data from 2004 is not currently available.

      Ozone monitoring data by county, for the 20 counties with the worst long- and short-term ozone measurements, 2000-2003

County# Average number of days per year with ozone levels >70 ppb Average number of days per year with ozone levels >85 ppb Average number of days per year with hourly ozone levels >95 ppb Average daily smog level during ozone season* 2000-03(ppb) Average of the peak hour smog level during ozone season* 2000-03 (ppb) Maximum daily value 2000-03 (ppb) Maximum hourly value 2000-03 (ppb)
Fresno 90 42 51 75 86 132 165
Tulare 93 42 44 76 85 117 140
Merced 92 40 38 74 83 125 138
Kern 89 37 39 74 83 127 156
Riverside 75 34 49 72 85 146 169
San Bernardino 65 26 37 69 82 153 184
Kings 74 24 27 70 79 110 127
El Dorado 35 11 14 61 68 137 156
Calaveras 49 11 14 64 72 108 134
Madera 50 10 13 65 73 110 141
Placer 34 10 15 59 69 115 142
Nevada 43 10 10 61 68 113 130
Los Angeles 26 10 20 53 67 152 194
Stanislaus 35 9 14 59 70 113 135
Tuolumne 53 9 8 65 72 104 132
Mariposa 50 9 6 63 69 103 135
Sacramento 27 8 13 56 67 120 142
Amador 33 4 9 61 69 102 121
Ventura 27 6 9 56 65 114 132
Butte 28 4 3 58 65 101 112

# Smog levels vary by county. In most urban counties there are multiple pollutant monitors in each county. We report the average value for each county between 2000 and 2003.

* Ozone season is May 1st through September 30th of each year.

Science panel upholds proposed standard

As with the reevaluation of the particulate standard in 2002, the major opponents of the proposed smog standards are big automakers, agriculture and the petroleum industry. Smog is formed by the reaction of nitrogen oxides (NOx) and volatile hydrocarbons (VOCs) in the atmosphere. Engine emissions from vehicles, boats, trains, and other mobile sources emit the majority of smog-forming chemicals in California. Engines release 80 percent of smog-forming NOx emissions, and 53 percent of VOCs in the state. Local air districts have enacted carpool lanes, clean car technologies, fleet restrictions and vehicle buy-backs as ways to reduce vehicle emissions.

Pesticides are another major source of smog. In San Joaquin Valley pesticides are the 6th largest source of VOCs behind livestock, two classes of vehicles, prescribed burning and oil and gas production. Air quality managers have estimated that each source will need to be reduced by 30 percent in order to achieve the hourly ozone standard. [Segawa 2005] The Department of Pesticide Regulation is considering reformulating pesticides, changing application methods, and reduced use as ways to curb smog-forming emissions.

Consumer products are the least commonly recognized smog source. In the Los Angeles area ordinary household products such as cleansers, cosmetics and paints are the second-leading source of air pollution, after auto tailpipe emissions. [Polakovic 2003]

The Alliance of Automobile Manufacturers, the American Petroleum Association, the Western States Petroleum Association and Engine Manufacturers Association all submitted comments critical of the state's draft ozone report, and testified against it to the independent committee of scientists charged with reviewing the standard.

In public comments, industry groups and their representatives claimed that the standard was unsupported and unenforceable. The Western States Automobile Association hired a physician, Dr. Nathan Rabinovitch, to testify that there was inadequate evidence of the special susceptibility of children, the elderly and infirm to ozone in controlled studies. [ARB(3) 2005] Actually, the suspected vulnerability of these groups makes it unethical to subject them to potentially dangerous exposures in controlled studies.

Dr. Rabinovitch has also come under scrutiny for his recent research that found no relationship between poor air quality and asthma-related illness in children with moderate-to-severe asthma. [Rabinovitch 2004] Dr. Rabinovitch claimed that while he initially found a relationship between pollution and health problems, the association "disappeared" when he adjusted for upper respiratory illness in study children. [Augé 2004] However, the state's review makes it clear that upper respiratory illness is strongly associated with air pollutants. [ARB(1) 2005] By claiming that parents stop worrying about air pollution and "focus on triggers that are really important" Dr. Rabinovitch is clearly swimming against the tide of thousands of air quality studies showing that asthmatics suffer from air pollution.

Another concern raised by the industry was that the proposed standard was too close to the maximum "natural" ozone concentrations, and therefore the standard would be unenforceable. They also argued that only one standard was needed, not hourly and daily standards. State scientists countered that the proposed standard was sufficiently above the maximum background concentration of 40 ppb, and that a daily standard was needed to reduce ozone concentrations outside of the Los Angeles area. Several agricultural groups—the California Citrus Mutual, California Cotton Ginners Association, California Cotton Growers Association, California Farm Bureau Federation, California League of Food Processors and Nisei Farmers League—have also signed on to criticism of the proposed standard, despite the fact that ozone is estimated to cause millions of dollars of damages to agricultural crops in the state. [ARB(1) 2005]

However, an expert review panel composed of nine leading air quality researchers from California universities unanimously rejected the industry's arguments and determined that the recommendations were "well supported" by scientific evidence. [ARB(4) 2005] They recommended that the Air Resources Board adopt the proposed standards, and reopen the standards for review if new research indicates additional risks for the developing baby or young child. [ARB(4) 2005]