The existing ambient standard for ozone (O3) for the State of California is 0.09 ppm (180 mg/m3) for a 1-hour averaging time. The standard was set in 1987. At the time, the Department of Health Services (DHS) concluded: “A one-hour 0.08 ppm standard provides a small, but adequate margin of safety

0.03 ppm (30 ppb, 42 µg/m 3) for one hour. The standard was adopted in 1969 and was based on the geometric mean odor threshold measured in adults. The purpose of the standard was to decrease odor annoyance. The standard was reviewed in 1980 and 1984 (CARB, 1984), and was not changed since no new relevant information had emerged. The U.S. EPA presently does not classify hydrogen sulfide as either a criteria air pollutant or a Hazardous Air Pollutant. However, several countries have short-term (usually 30 minute) standards for hydrogen sulfide, as well as long-term (24 hour) standards. This report focuses on key studies in humans and animals bearing on the healthprotectiveness of the CAAQS for hydrogen sulfide. It also includes a discussion of whether significant adverse health effects would reasonably be expected to occur, especially among infants and children, at exposure concentrations below the CAAQS of 30 ppb, based on the findings of published studies. Additional research on odor sensitivity in infants, children, and adults would be useful in evaluating the standard. This would include: (1) testing of the odor threshold for H2S using the most current methodology among groups of healthy persons of both sexes in different age ranges; (2) odor testing of hydrogen sulfide in adolescents or younger

iAbstract Epidemiological evidence indicates that present-day ambient particulate matter (PM) and/or sulfate air pollution exposures are associated with adverse health effects in children, including that: Short-term PM and/or sulfate exposures to children are associated with: • reduced pulmonary function; • increased respiratory symptoms in asthmatics (e.g., asthma attacks) and non-asthmatics; • increased incidence of respiratory doctor’s visits; • increased incidence of emergency department (ED) visits and hospital admissions (HA’s); • increased mortality, and; • especially increased infant morbidity and mortality; Long-term chronic PM and/or sulfate exposures to children are associated with: • reduced lung function; • increased respiratory symptoms; and, • increased infant mortality, intrauterine growth reduction, or pre-term delivery.

Sulfur dioxide is an irritant gas commonly emitted by coal fired power plants, refineries, smelters, paper and pulp mills and food processing plants. Both controlled laboratory studies and epidemiology studies have shown that people with asthma and children are particularly sensitive to and are at increased risk from the effects of SO2 air pollution. Asthmatic subjects exposed to levels of SO2 within regulatory standards have demonstrated increased respiratory symptoms such as shortness of breath, coughing and wheezing, and decrements in lung function. Physiological differences between children and adults such as lung volume and ventilation rate make children more sensitive to the effects of SO2 compared to healthy adults. In general, children’s exposure to SO2 is also greater than that of adults since they spend more time outdoors and are more physically active. Controlled exposures to SO2 have shown statistically significant reductions in lung function at concentrations as low as 0.1 to 0.25 ppm. Epidemiologic studies have seen mortality associated with very small increases in ambient SO2 in the range of 10 – 22 ppb. Low birth weigh is associated with SO2 concentrations in the range of 22-40 ppb. The studies assessed

Nitrogen dioxide (NO2) is the most abundant and toxic of the nitrogen oxides formed from combustion of fossil fuels, and ambient concentrations are related to traffic density as well as point sources. Indoor NO2 levels may exceed those found outdoors. When inhaled, NO2 persists to the lung periphery because of its relatively low solubility. Greater than 60 % of inhaled NO2 is deposited, predominantly in the centri-acinar region, and the fraction deposited increases with exercise. Epidemiological studies have found relationships between both outdoor and indoor NO2 levels and respiratory illness, decrements in lung function, and exacerbation of asthma, especially in children. Outdoor NO2 was associated with increased infant mortality and intrauterine mortality in Sao Paulo, Brazil. However, these studies are subject to exposure misclassification, and generally fail to consider a possible role of indoor and outdoor particle exposure as a confounding factor. NO2 may represent a marker for exposure to traffic- or combustion-related pollution in these epidemiological studies. Human clinical studies generally fail to show effects of exposure concentrations at or below the

Epidemiological evidence indicates that present-day ambient particulate matter (PM) and/or sulfate air pollution exposures are associated with adverse health effects in children, including that: Short-term PM and/or sulfate exposures to children are associated with: • reduced pulmonary function; • increased respiratory symptoms in asthmatics (e.g., asthma attacks) and non-asthmatics; • increased incidence of respiratory doctor’s visits; • increased incidence of emergency department (ED) visits and hospital admissions (HA’s); • increased mortality, and; • especially increased infant morbidity and mortality; Long-term chronic PM and/or sulfate exposures to children are associated with: • reduced lung function;

2A. Introduction and Overview In this section, we provide a general overview of the health effects of lead. In Section II, we discuss the evidence for the adverse outcome most relevant to current concentrations of blood lead in children, neurotoxicity. We also provide background on the Centers for Disease Control (CDC) guidelines concerning the blood level of concern for children. Since the health

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regulations described below after considering all comments, objections, and recommendations regarding the proposed action.

the University of California Office of the President for their peer reviews of the public health goal documents, and gratefully acknowledge the comments received from all interested parties.