Air Pollution Research Reports/Studies - Health Effects of Air Pollution

This page last reviewed August 13, 2008

Completed Projects are listed under the following sub-categories:

Carbon Monoxide Nitrogen Oxides
Children's Health Ozone
Clinical Studies Particulate Matter
Fuels Population Studies
General Toxic Air Contaminants

Carbon Monoxide

CARDIAC RESPONSE TO MONOXIDE IN THE NATURAL ENVIRONMENT. Principal Investigator: Steven D.Colome, Sc.D. University of California, Irvine. 1992. A3-138-33.

EFFECTS OF EXPOSURE TO LOW-LEVEL CARBON MONOXIDE AT SEA LEVEL AND HIGH ALTITUDE IN SENSITIVE SUBJECTS. University of California, Irvine.1991. A833-159, A6-203-33, and A3-138-33.

objectives: To determine whether the current high-altitude standard for carbon monoxide is justified in view of the fact that the parameters used in the model calculations for deriving the standard were flawed. To validate with state-of-the-science techniques some of the variables used in calculating the sea level CO standard. Three studies were funded to address specific issues involved in order to draw definitive conclusions.

Findings: In patients suffering from ischemic heart disease, carbon monoxide exposure reduced the time before onset of angina to a greater degree at a simulated altitude of 7,000 feet than at sea level.

Importance to ARB's Program: The results indicated the need for a separate high altitude carbon monoxide standard for the State and reconfirmed the existing sea level standard during the recent review of the standard by ARB.

A COORDINATED MULTIDISCIPLINARY RESEARCH PROGRAM ON CARBON MONOXIDE HEALTH EFFECTS. Principal Investigator: Michael T. Kleinman, Ph.D. University of California, Irvine. 1990. A6-203-33.

AN EPIDEMIOLOGICAL SURVEY OF CARBOXYHEMOGLOBIN IN NONSMOKERS IN LOS ANGELES. Department of Public Health, Berkeley. 1975. ARB-847

INFLUENCE OF CARBON MONOXIDE ON CARDIAC DYNAMICS IN NORMAL AND CARDIOVASCULAR STRESSED ANIMALS. Principal Investigator: Steven M. Horvath, Ph.D. University of California, Santa Barbara. 1974. ARB-2096.

Children's Health

TRAFFIC POLLUTION AND CHILDREN'S HEALTH: REFINING ESTIMATES OF EXPOSURE FOR THE EAST BAY CHILDREN'S RESPIRATORY HEALTH STUDY. Principal Investigator: Bart Ostro, Ph.D. OEHHA. 2008. 03-327.

EPIDEMIOLOGIC INVESTIGATION TO IDENTIFY HEALTH EFFECTS OF AMBIENT AIR POLLUTANTS IN CALIFORNIA.  Principal Investigator: John M. Peters, M.D., Sc.D. University of Southern California. 2004. 94-331.

objectives: The objectives of this study are to: 1) determine whether long-term exposure to ambient air pollutants during childhood leads to changes in lung function or adverse health effects, especially chronic respiratory effects; and 2) quantify the prevalence and severity of the observed effects, as well as the levels of exposure at which effects occur.  The study will evaluate 5,400 school children residing in 12 southern California communities, 3,600 of which have already been studied for two years as part of a similar study begun in 1991.

Importance to the ARB: The ambient air quality standards set by the ARB are determined, in part, by the reactivity of the population most sensitive to a particular pollutant (e.g., children, cardiac patients, asthmatics).  However, most of the health studies used to set both State and federal standards have focused on short-term effects; little has been done to determine the cumulative effects of long-term exposure, especially for children growing up in smoggy environments.  The results from this study will be used to validate and update existing exposure models and evaluate the effectiveness of current ambient air quality standards.

DETERMINATION OF THE ELEMENTAL CARBON AND ORGANIC CARBON CONCENTRATIONS DURING THE SOUTHERN CALIFORNIA CHILDREN’S HEALTH STUDY , 1999-2001.  Principal Investigator: Lynn G. Salmon California Institute of Technology, Pasadena. 2004. 01-309.

INTERIM REPORT FOR THE FRESNO ASTHMATIC CHILDREN'S ENVIRONMENT STUDY (FACES). University of California, Bekerley. 2002. 99-322 & 99-323

DETERMINATION OF THE ELEMENTAL CARBON, ORGANIC COMPOUNDS, AND SOURCE CONTRIBUTIONS TO ATMOSPHERIC PARTICLES DURING THE SOUTHERN CALIFORNIA CHILDREN’S HEALTH STUDY.  Principal Investigator: Lynn G. Salmon California Institute of Technology. 2000. 98-320.

objectives: The objectives of this project are to:  1) analyze all archived quartz fiber filters from the Children’s Health Study, from 1994 and 1996-98, for their organic and elemental carbon content; 2) analyze the 1995 quartz fiber filters for individual organic compounds that act as tracers for source emissions; and 3) use the resulting organic compound concentration data to model the source apportionment of the organic aerosol and aerosol mass measured during 1995.

Importance to ARB’s Program: The attention of health investigators has recently been focused on the impacts of combustion-derived particles on human health.  By determining the concentration of organic carbon compounds and elemental carbon particles in southern California from 1995-1998, this project will provide an important piece of the information needed to complete the PM2.5 database for the Children’s Health Study (Contract No. 94-331).

EPIDEMIOLOGIC INVESTIGATION TO IDENTIFY CHRONIC HEALTH EFFECTS OF AMBIENT AIR POLLUTANTS IN SOUTHERN CALIFORNIA (Three-phase project). Principal Investigator: John M. Peters, M.D. University of Southern California.1996. A033-186.

objectives: The objectives of the project in its entirety are: 1) to determine whether long-term exposure to southern California's unique mixtures and concentrations of ambient air pollutants during childhood development leads to changes in lung function or identifiable adverse health effects, especially chronic respiratory effects; and 2) to quantify the prevalence and severity of the observed health effects and the levels of exposure to specific pollutants at which the effects occur.
The primary specific objective of Phase I was to produce a cost-effective research plan for Phases II and III that offered the greatest likelihood of success in meeting the overall project objectives, and to develop a final detailed protocol for Phase II.
The specific objectives of Phase II are to verify community exposure classifications, collect data to be used in personal exposure models, gather baseline health and lifestyle data for the children under study, perform cross-sectional analyses to determine community differences that are a function of air pollution, and finalize the Phase III protocol, based on Phase II findings.

Findings: Phase I: 1) Based on potential long term exposure health effects, and on high ambient concentrations, the project should focus on ozone, particulate pollution, nitrogen dioxide, and acidic pollutants (nitric, hydrochloric, and organic acids); 2) to achieve statistically meaningful results, twelve communities with different ratios of these pollutants should be included in the study; 3) during Phase II, the project should study between-community differences in the health of school children from the fourth, seventh, and tenth grades, and then follow these children's health status through their high school graduation (year 2 of Phase II, and Phase III); and 4) a state-of-the-science exposure assessment program should be implemented to help separate out the effects of one pollutant from another. Phase II: This phase of the study was recently completed. ARB staff are in the process of reviewing the data for completeness and accuracy.

Importance to ARB's Program: Information obtained from this project, which is the cornerstone of the ARB's Long-Term Exposure Health Effects Research Program, will allow, for the first time, quantitative consideration of long-term exposure effects of ambient criteria air pollutants. The information will have direct application in the review and, if necessary, revision of California's health-based ambient air quality standards. The project will also provide information necessary to determine the need for an ambient air quality standard for atmospheric acidity.

DEVELOPMENT OF A PROTOCOL TO TRACE AND STUDY SCHOOL CHILDREN EXPOSED TO VINYL CHLORIDE. Principal Investigator: Richard Ziskind, Ph. D. Science Applications, Inc. 1984. A1-082-32.

HEALTH EFFECTS IN CHILDREN EXPOSED TO VINYL CHLORIDE. Principal Investigator: Richard A. Ziskind, Ph. D. Science Applications, Inc. 1981. 68-2986.

Clinical Studies

ARE MUCIN AND MUCIN RNA RELIABLE MARKERS FOR HYPERSECRETION IN HUMANS WITH IRRITANT-INDUCED BRONCHITIS? Principal Investigator: Carol Basbaum, Ph.D. University of California, Irvine.1992. A933-095.

objectives: To develop and evaluate two new test methods for early detection of increased mucus production in the respiratory tract of humans. One measures an increase in the levels of mucin in airway lining fluid; the other identifies a signal inside the cells that indicates increased mucus production. Increased mucus production is one of the first signs of chronic bronchitis.

Findings: The study was successful in developing and validating the new test methods and in assuring a high degree of sensitivity in detecting changes in mucus production.

Importance to ARB's Program: The tests have been included for further evaluation in other pollutant exposure studies.

AIR POLLUTION EFFECTS ON NASAL FUNCTION. Principal Investigator: Homer A. Boushey, M. D. University of California, San Francisco. 1988. A5-163-33.

EFFECTS OF AIR POLLUTION ON AIRWAY FUNCTION. Principal Investigator: J. A. Nadel. 1982. A9-115-30.

DEVELOPMENT AND APPLICATION OF METHODS FOR ESTIMATING INHALABLE AND FINE PARTICLE CONCENTRATIONS FROM ROUTINE HI - VOL DATA. Principal Investigator: John Trijonis and Marilyn Davis. Santa FE Research Corporation. 1981. A0-076-32.

RESPONSE OF INDIVIDUALS WITH REACTIVE AIRWAY DISEASE TO ATMOSPHERIC POLLUTANTS INCLUDING SULFATES. Principal Investigator: Roger Detels, M. D. UCLA School of Public Health. 1980. A6-216-30.

PHYSIOLOGICAL EFFECTS OF AIR POLLUTANTS IN HUMANS SUBJECTED TO SECONDARY STRESS. Principal Investigator: Jack D. Hackney, M. D. Rancho Los Amigos Hospital Inc. 1974. ARB-2-372.

PHYSIOLOGICAL EFFECTS OF AIR POLLUTANTS DURING LONG AND SHORT TERM WORK IN 25°C AND 35°C TEMPERATURE. Principal Investigator: Peter B. Raven, Ph.D. University of California, Santa Barbara. 1974. ARB-2098.

Fuels

STUDY OF NEUROLOGICAL EFFECTS OF LOW-LEVEL METHANOL EXPOSURE IN NORMAL AND FOLATE-DEFICIENT SUBJECTS. University of California, San Francisco. 1994. A033-172.

objectives: To determine the neurological effects of exposure to methanol vapor using normal and folate-deficient human volunteers. Because methanol is used as an alternative fuel for motor vehicles, research is needed to determine whether exposure to the vapors is harmful at the threshold limit value (TLV). TLVs are the maximum allowable concentrations at a work site. Folate-deficient subjects need to be tested as a sensitive subgroup because folate tends to inhibit the formation of formate, a toxic metabolite of methanol.

Findings: In normal individuals, exposure to TLV levels of methanol causes a transient increase in blood methanol levels but no change in formate levels or in neurological test results. Evaluation of the folate-deficient subjects is currently in progress.

Importance to ARB's Program: The findings from this project will be used to estimate the health risk posed by methanol vapors during motor vehicle refueling activities.

DERMAL ABSORPTION OF METHANOL AND METHANOL/GASOLINE MIXTURES. Principal Investigator: O.G. Raabe, Ph.D. University of California, Davis. 1992. A933-186.

objectives: To determine whether the skin absorption of methanol is increased in methanol/gasoline mixtures. Because methanol is used as an alternative fuel for motor vehicles, research is needed to determine whether skin absorption of methanol from accidental spills is enhanced by the presence of gasoline in methanol/gasoline mixtures.

Findings: Methanol/gasoline mixtures with greater than 50 percent gasoline increased the relative degree to which methanol was absorbed by rat skin. The total amount of methanol absorbed from the mixtures, however, was less than that from pure methanol fuel because of the lower content of methanol in the mixtures.

Importance to ARB's Program: These findings helped ARB conclude that accidental spills of methanol/gasoline mixtures that occur in gas stations are not likely to pose a risk to humans.

General

THE EFFECT OF SMOKE FROM THE BURNING OF RICE STRAW AND OTHER VEGETABLE MATTER RESIDUE ON AIRWAY INFLAMMATION AND PULMONARY FUNCTION IN HEALTHY, ASTHMATIC AND ALLERGIC INDIVIDUALS.  Principal Investigator: Colin Solomon, Ph.D. University of California, San Francisco. 2003. 97-322.

Objective: The objective of this project is to investigate the effects on human respiratory health of particles inhaled from common sources of smoke produced by burning of vegetable matter, specifically by determining the effects of:  1) an acute exposure at two different concentrations to rice straw smoke on airway inflammation and pulmonary function; 2) total smoke exposure (single vs. multi-day) on airway inflammation and pulmonary function; and 3) asthma and allergy status on airway inflammation and pulmonary function responses to smoke from rice straw burning.

Importance to ARB’s Program: Past epidemiology studies have provided consistent and coherent data linking observed health effects and PM exposure.  However, PM10 is a complex air pollutant made up of many different kinds and sizes of particulates.  It is very likely that different kinds of particles, of varying sizes, from different sources of particulate air pollution, act by a variety of biological mechanisms to cause the various health effects seen with PM10 exposure.  One source of PM exposure of particular concern in California’s central valley is smoke from the burning of vegetative matter, including rice straw residues. The results from this study will provide valuable information necessary to adequately evaluate the existence, nature, and extent of adverse health effects associated with exposure to this source of particulate air pollution in California. The results of this project may also assist the ARB in determining whether additional actions, if any, are needed to address burning of agricultural and forest wastes.

CHRONIC TOXICITY OF MIXED AIR POLLUTANTS: OXIDANTS, ACIDS, AND FINE PARTICLES. Principal Investigator: William. J. Mautz, Ph.D. University of California, Irvine.1993. A833-104.

objectives: To determine the adverse effects resulting from long term (9 months) episodic exposures to low levels of ozone both alone and in combination with other pollutants, simulating ambient conditions in Los Angeles.

Findings: The effects included lung structural changes and a breakdown in lung defense mechanisms. The magnitude of adverse effects was greater in the ozone group than in the clean air group, but was statistically significant only in the group exposed to ozone with other pollutants. Although the acute effects of air pollution appear to be mainly caused by oxidants, the chronic effects may be influenced to a large extent by the presence of particulate material and ambient acids.

Importance to ARB's Program: These findings will be useful in evaluating the chronic effects of air pollution and in estimating the risk from air pollution for various districts.

A PILOT SURVEY OF HUMAN LUNG TISSUE FOR AIR POLLUTION EFFECTS IN LOS ANGELES COUNTY. University of Southern California.1990. A6-202-33.

objectives: To test the feasibility of collecting pathological specimens for analysis of lung tissue for air pollution effects from victims of traffic accidents and homicides and correlating this information with demographic, health, and lifestyle data. This study was a part of ARB efforts to determine chronic and lifetime effects of exposure to ambient air pollution.

Findings: The method was demonstrated to be feasible if it includes individuals younger than 15 years. Presence of lung lesions at a young age was higher than expected. ARB staff recommend further studies to determine whether these findings are linked to air pollution.

Importance to ARB's Program: Most existing air quality standards are aimed at protecting the public against acute effects. Information on chronic effects is critical for future review of the standards.

EFFECT OF POLLUTANT EXPOSURE AMBIENT AIR IN CHILDHOOD AND ADULTHOOD. Principal Investigator: David H. Wegman, Ph.D. University of California, LA. 1987. A4-068-33.

21-DAY EXPOSURE TO MIXED AIR POLLUTANTS: EFFECTS ON LUNG AIRWAYS AND MACROPHAGES. Principal Investigator: Robert F. Phalen, Ph. D. University of California, Irvine. 1987. A6-126-33.

INDUCTION OF ARYL HYDROCARBON HYDROXYLASE IN CULTURED PERIPHERAL LYMPHOCYTES IN COLLEGE STUDENTS EXPOSED TO AIR POLLUTANTS. Principal Investigator: Robert W. Teel, Ph.D. University of Loma Linda , CA. 1978. A6-104-30.

HEALTH EFFECTS OF ATMOSPHERIC SALTS AND GASES OF SULFUR AND NITROGEN IN ASSOCIATION WITH PHOTOCHEMICAL OXIDANT. Principal Investigator: T. Timothy Crocker, M. D. University of California, Irvine. 1972. 3-197

Volume I

Volume II

Nitrogen Oxides

EFFECTS OF NITROGEN DIOXIDE ON AIRWAY INFLAMMATION IN ALLERGIC ASTHMATIC SUBJECTS. Principal Investigator: Colin Solomon, Ph.D. University of California, San Francisco. 2004. 00-337.

THE HEALTH IMPACT OF NITRIC OXIDE:  EFFECTS ON LUNG FUNCTION AND CELLULAR AND BIOCHEMICAL PROCESSES IN HEALTHY HUMANS.  University of California, San Francisco. Principal Investigator: Stephen C. Lazarus, M.D. University of California, San Francisco. 2001. 97-329.

objectives: The objectives of this project are to: 1) review the basic scientific, clinical, and epidemiologic literature relating to nitric oxide (NO); 2) assess the effects of ambient levels of NO on humans; and 3) evaluate the potential for ambient nitric oxide to cause or worsen human disease.

Importance to ARB’s Program: There is reason to suspect that chronic exposure to even low levels of ambient NO may have significant effects in the body.  This concern is supported by epidemiologic studies that indicate an association between ambient concentrations of nitric oxide and the incidence of adverse health effects in humans, including respiratory infections, croup, asthma, and bronchitis.  It is expected that a comprehensive literature review will provide the ARB with sufficient information to determine the potential for ambient concentrations of NO to cause or modify human disease.  It will also allow the ARB to determine whether enough data exist to address the concerns regarding ambient NO exposure and possible adverse human health effects or, if not, what additional studies are needed.

THE EFFECTS OF MULTI-DAY EXPOSURE TO NITROGEN DIOXIDE ON CELLULAR IMMUNITY: HUMAN MACROPHAGE RESPONSES. Principal Investigator: Michael T. Kleinman. University of California, Irvine.1998. 95-311.

objectives: To determine whether repeated short-term exposure to nitrogen dioxide (NO2) causes changes in macrophage function such as phagocytic activity and the ability to release inflammatory substances, and to determine whether NO2 exposure causes macrophage overactivation, which could lead to increased cellular damage.

Findings: The results indicate that NO2 exposure does not affect the body's production of macrophages, and that NO2 exposure does not affect the potential ability of macrophage cells to recognize and ingest invading pathogens such as bacteria or viruses. Nor did NO2 exposure appear to alter the ability of macrophage cells to recruit other infection-fighting cells. However, following NO2 exposure, macrophages were found to become "overexcitable" and release more potentially toxic inflammatory chemicals than normal. This could cause tissue damage in the lungs of humans exposed to NO2 in the ambient environment.

Importance to ARB's Program: Because oxides of nitrogen are common ambient air pollutants, and because epidemiologic evidence suggests that exposure to ambient NO2 is associated with increased incidence of respiratory symptoms, infection, and illness in humans and depressed immune system function in animals, the ARB needs to determine the actual effects of NO2 on humans so that this knowledge can be used in considering air pollution standards. 

THE EFFECTS OF MULTI-DAY EXPOSURE TO NITROGEN DIOXIDE ON HUMAN CELLULAR IMMUNITY. Principal Investigator: John R. Balmes. University of California San Francisco.1997. 93-317.

objectives: To determine whether extended exposures to nitrogen dioxide (NO2 ) at the current California one-hour ambient air quality standard level (0.25 ppm) can compromise the human immune system. Recent evidence suggests that low-level NO2 exposures may weaken the immune system, compromising resistance to infections.

Findings: The results of this study, when viewed with other clinical and epidemiological investigations, do not resolve the uncertainties of NO2 health and immune system impacts. It appears that NO2 can impact the cellular processes of the lung by its simple oxidative damage potential as is found with ozone exposure. These oxidative injuries are reflected by the neutrophil cell increases reported in this study. Further, other studies find that NO 2 appears to produce complex alterations in immune system function or function of individual cellular components of the immune system. However, the timeframes of this and other past clinical exposure studies were short, and little change has been found, even -- in this study -- following exposure to relatively high levels of NO 2. The investigators suggest that more prolonged exposures may impact immune system function. Such studies area very difficult to perform on human volunteers exposed in experimental chambers.

Importance to ARB's Program: The study provides the information required by the ARB to establish whether extended exposures to NO2 at the current standard level poses a threat to public health. It does not support the findings of other studies in which NOx was observed to cause changes in the immune system.

CORRELATIVE AND SENSITIVE DISCRIMANTS FOR AIR QUALITY CONTROL. Principal Investigator: Russell P. Sherwin, M.D. USC School Of Medicine Los Angeles, CA. 1989. A3-083-33.

EFFECTS OF AMBIENT AIR POLLUTION ON THE LUNG AND IMMUNE SYSTEM. Principal Investigator: Russell P. Sherwin, M. D. University of Southern California. 1989. A4-160-33.

EFFECTS OF NITROGEN DIOXIDE ON AIRWAY CALIBER AND REACTIVITY IN ASTHMATIC SUBJECTS; EFFECTS OF NITROGEN DIOXIDE ON LUNG LYMPHOCYTES AND MACROPHAGE PRODUCTS IN HEALTHY SUBJECTS; NASAL AND BRONCHIAL EFFECTS OF SULFUR DIOXIDE IN ASTHMATIC SUBJECTS. Principal Investigator: Homer A. Boushey, Jr., M. D. University of California, San Francisco. 1988. A6-200-33.

NITROGEN DIOXIDE EFFECTS ON PROGRESSION OF MOUSE LYMPHOMA, A BLOOD CELL MALIGNANCY. Principal Investigator: Arnis Richters, Ph.D. School of Medicine Los Angeles, CA. 1988.A5-162-33.

THE ROLE OF AIR POLLUTANTS IN FACILITATION OF CANCER CELL METASTASIS. Principal Investigator: Arnis Richters, Ph.D. School of Medicine Los Angeles, CA. 1984. A2-128-33.

NEW APPROACH FOR DETECTION HEALTH HAZARDS OF NO2 INHALATION. Principal Investigator: Arnis Richters, Ph.D. School of Medicine Los Angeles, CA. 1983. A0-106-32.

IN VIVO FATE OF NITROGENOUS AIR POLLUTANT DERIVATIVES. Principal Investigator: Norris J. Parks. University of California, Davis. 1982. A0-031-31.

NEW APPROACH FOR DETECTING HEALTH HAZARDS OF NO2 INHALATION. Principal Investigator: Arnis Richters, Ph.D. School of Medicine Los Angeles, CA. 1981. A9-076-31.

IN VIVO FATE OF NITROGENOUS AIR POLLUTANT DERIVATIVES. Principal Investigator: N. J. Parks. University of California, Davis. 1979. A7-190-30.

FATE AND DISTRIBUTION OF INHALED NITROGEN DIOXIDE IN THE NON - HUMAN PRIMATE. Principal Investigator: Elliot Goldstein, M. D.University of California, Davis. 1974. ARB-1116.

THE FATE OF NITRIC OXIDE IN THE MAMMALIAN SYSTEM USING N15 AS TRACER AND ISOTOPIC DILUENT. Principal Investigator: Gustave Freeman, M. D. and Michael Anbar, Ph.D. Stanford Research Institute. 1973. ARB-2-291.

Ozone

EFFECTS OF CONTROLLED OZONE EXPOSURE IN VOLUNTEERS WITH CARDIOVASCULAR DISEASE. Principal Investigator: Henry Gong, Jr., M.D. Environmental Health Services. May 2000. 93-327.

objectives: To conduct a pilot study to determine whether acute exposure to ozone can adversely affect people suffering from ischemic heart disease or hypertension.

Findings: The investigators were unable to locate, enroll, and study an adequate number of patients with ischemia, so the study was performed on patients with hypertension. While the study reports no clinically manifested adverse consequences of brief ozone exposure to hypertensives, even though this group is considered to be at risk, it does suggest a physiologic basis for concern for those with existing cardiovascular disease. Further experimental work of this type will be required to resolve the issue.

Importance to ARB's Program: In recent years epidemiological studies have reported a consistent correlation between urban air pollution levels and an increase in mortality. In addition, it appears that people suffering from cardiac and/or pulmonary disease are more prone than others to die from effects of air pollution. However, prior to this study, controlled laboratory studies had not reported any biological response(s) that could explain the mortality effect resulting from ambient pollutant exposures. This study provides evidence of biological response(s) to ozone that suggest that ozone exposure added stress to the hearts of people studied. The evidence from this study suggests one mechanism whereby ozone could impact the well-being of people with existing heart problems. The results provide further justification for modification of existing public health advisories to explicitly protect people with heart disease.

EFFECTS OF OZONE ON PROTEASES AND PROTEASE INHIBITORS OF THE HUMAN AND RAT LUNG. Principal Investigator: William B. Mautz, Ph.D. University of California, Irvine.2000. A033-175.

objectives: To perform a detailed analysis of the biochemical events (changes in proteases and protease inhibitors) that are believed to precede connective tissue fibrosis (scarring) in lungs following exposure to air pollutants. In this study levels were measured of connective tissue proteases and protease inhibitors in lung lavage fluid collected from rats and humans following acute and/or chronic exposures to ozone alone or in combination with nitric acid.

Findings: No changes in protease levels were found in rats or humans for any of the exposure conditions. The investigators did find that, in both humans and rats, relatively low-level acute (but not subacute or chronic) ozone exposures resulted in striking increases in the protease-inhibiting capacity of lung lavage fluid. These increases in protease-inhibiting capacity were due to extensive cellular membrane damage and the release of intracellular contents and do not imply that acute ozone exposure offers a protective effect by "increasing" the amount of inhibitory species in lung fluids. Indeed, over time, because of the potential for permanent tissue damage, exposure to ozone could lead to an overall reduction in the production of protective inhibitory species. The study confirms that acute ozone exposure does cause tissue damage; however, it is unclear whether the mechanism leading to pulmonary fibrosis is tied to changes in protease levels or to the possible reduction over time of protease inhibitory species due to direct tissue damage.

Importance to ARB's Program: California's current ambient ozone standard is based on a number of factors that include short-term changes in lung function. The results of this study will contribute to the determination of whether the standards adequately protect the public against the long-term effects of ozone exposure.

PULMONARY MACROPHAGE RELEASE OF INFLAMMATORY CYTOKINES AFTER MULTI-DAY NITRIC ACID VAPOR AND OZONE EXPOSURE. Principal Investigator: Paul Blanc, MD, MSPH. University of California, San Francisco.2000. 93-331.

objectives: The magnitude of breathing capacity declines following acute single exposure to ozone progressively diminishes with successive days of ozone exposure. The objective of this study was to include additional health effects evaluation parameters (levels of cytokines) for ARB-funded clinical studies in progress that are evaluating the multi-day exposure effects of ozone and nitric acid. (Cytokines are biochemical mediators that are indicators of lung injury and are also responsible for inflammatory changes in the lung.)

Findings: The utility of this work awaits the completion of the core clinical study. Specific observations made in this study include: (1) Two of the measured cytokines produced a clear indication of pollution-related response; (2) responses to ozone were found to be similar in 1-day and 4-day exposure protocols; (3) nitric acid was found to stimulate production of the two cytokines by itself but cytokine levels were reduced when nitric acid and ozone were administered together. The findings of this study should prove useful in the interpretation of the results of the core clinical exposure study -- they provide a mechanistic link among pollutant exposure, observed lung function changes, and injury observations.

Importance to ARB's Program: Adding cytokine measurements to the ongoing studies will permit better evaluation of multi-day exposure effects of ozone and/or nitric acid.

RELATIONSHIP BETWEEN ACUTE OZONE RESPONSIVENESS AND THE CHRONIC LOSS OF LUNG FUNCTION IN RESIDENTS EXPOSED TO RECURRENT OXIDANT AIR POLLUTION. Principal Investigator: Henry Gong, Jr., M.D. University of California, Los Angeles.1998. A6-158-33.

objectives: In the early l970s a long-term study of chronic obstructive respiratory disease was initiated in Los Angeles County to monitor lung function responses in residents of three air-polluted areas and one less-polluted site. By the mid-1980s, it was found that subjects living in the polluted areas exhibited more rapid lung function declines than those living at the less-polluted site. This study was conducted to retest a subset of the participants of the earlier study to determine what, if any, changes had occurred in lung function over an additional 5-year period.

Findings: Residents of the most polluted area exhibited normal rates of lung function loss over the retest period. In a separate set of tests, subjects with the most severe losses in lung function were found to have the same sensitivity to acute ozone exposures as subjects with less lung function damage.

Importance to ARB's Program: It was hoped that this study would shed light on chronic effects of exposure to ambient ozone. It did not prove useful for clarifying this issue; findings of lung function decline proved equivocal. Uncertainties remain with regard to the chronic effects of air pollution on human health; It is premature to discount the earlier long-term findings. These uncertainties can only be resolved through further studies with stable funding.

USE OF SPUTUM INDUCTION TO OBTAIN AIRWAY LINING FLUID AFTER OZONE EXPOSURE: A PILOT STUDY TO VALIDATE SPUTUM INDUCTION AS AN ALTERNATIVE TO BRONCHOSCOPY. Principal Investigator: JOHN V. FAHY. University of California, San Francisco.1995. 92-340.

objectives: To validate a simple, safe method (sputum induction) of collecting samples of airway lining fluid and cells from human lungs after exposure to ozone. The new method would replace the present complicated and invasive procedure, bronchoscopy.

Findings: Physiological responses to ozone were evident in the lung function measurements. Biochemical indicators of cellular change were found, indicating cellular damage. Overall, this pilot-level study supports the use of sputum induction as an alternative to invasive lavage/biopsy methods.

Importance to ARB's Program: Sputum induction can now be applied to a small cohort of children participating in the ARB's epidemiological study (contract no. A033-186, 1996) and other clinical studies to determine the effects of repeated and long-term exposures to pollutants and to understand the sequential course of changes taking place in human lungs.

EVALUATION OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE PATIENTS FOR OZONE SENSITIVITY: VALIDATION OF HEALTH ADVISORIES. Principal Investigator: Henry Gong, Jr. M.D. University of California, Los Angeles. 1995. A133-123.

objectives: To determine whether people with chronic obstructive pulmonary disease (COPD) are more sensitive than healthy humans to low levels of ozone exposure such as those commonly observed during smoggy days in the Los Angeles area.

Findings: After low-level ozone exposure, small but statistically significant changes in FEV1 (forced expiratory volume in one second) were found in both healthy and COPD subjects. Although these changes were small, the effects on the lung function of emphysemics, who are already at a decreased lung performance level, are considered adverse, since these changes cannot be accommodated without a health risk.

Importance to ARB's Program: The results will be useful in evaluating and, if necessary, modifying the health advisories issued by local air pollution control districts when pollutant levels reach various alert stages.

THE EFFECTS OF OZONE INHALATION ON FIBROBLAST ACTIVATION IN THE LUNG: POSSIBLE RELATIONSHIP TO LONG-TERM FIBROTIC LUNG CHANGES. Principal Investigator: Homer Boushey, M.D. University of California, San Francisco. 1994. A133-122.

objectives: To determine whether ozone exposure stimulates human fibroblasts. (Fibroblasts are lung cells responsible for fibrotic changes, which can be harmful. While chronic exposure to ozone is known to cause some fibrotic changes in animal lung, there are no documented studies that similar changes can occur in humans.)

Findings: Ozone exposures were associated with increased levels of a substance, cytokine, that is implicated in the pathogenesis of lung fibrosis. Other measures of cellular changes related to fibrosis were not found to increase following ozone exposure.

Importance to ARB's Program: The results of this study provide a tool to be used in further studies of chronic effects to humans of ozone exposure.

STUDIES OF YOUNG ADULT FEMALE RESPONSES TO ACUTE OZONE EXPOSURE. Principal Investigator: William C. Adams, Ph.D. University of California, Davis. 1992. A933-096 and A033-176.

objectives: To determine differences between lung function responses to ozone in healthy women and men during exercise. To confirm the previous observation that menstrual cycles are disrupted and that women in the early phase of the cycle (when progesterone levels are lower) respond more strongly than men to ozone.

Findings: Brief single exposures to Stage II alert levels of ozone (.30 ppm) disrupted some specific hormone responses in over half the women studied. The changes included surges in estrogen levels in the latter half of the menstrual cycle and delay in ovulation.

Importance to ARB's Program: Further research including blood hormone levels is needed to understand the implications of these observations before modifying the health advisories issued during various alert levels for air pollution on smoggy days in the Los Angeles area.

STUDY OF AIR POLLUTION: EFFECTS OF OZONE ON NEUROPEPTIDE - MEDIATED RESPONSES IN HUMAN SUBJECTS. Principal Investigator: H. A. Baushey, Jr. , M.D. University of California, San Francisco. 1991. A833-158.

EFFECTS OF OZONE ON CELLULAR SYNTHESIS AND VIRAL REPLICATION IN VITRO. Principal Investigator: Yuan Chung Zee. University of California, Davis. 1987. A5-153-33.

RELATIONSHIP BETWEEN AIR QUALITY AND THE RESPIRATORY STATUS OF ASTHMATICS IN AN AREA OF HIGH OXIDANT POLLUTION IN LOS ANGELES COUNTY. School of Medicine, Los Angeles, CA. 1987. A1-151-33 AND A4-135-33.

PHYSIOLOGICAL RESPONSES OF HEALTHY HUMAN SUBJECTS CONSEQUENT TO INHALATION OF NO2, O3, AND NO2 PLUS O3 DURING HEAVY, SUSTAINED EXERCISE. Principal Investigator: William C, Adams, Ph.D. University of California, Davis. 1986. A4-070-33.

CHANGES IN LUNG FUNCTION & EXPOSURE TO OXIDANTS. Principal Investigator: Roger Detels, MD, MS. University of California, Los Angeles. 1986. A0-133-32.

THE ROLE OF NO2 AND O3 IN CANCER METASTASIS AND IN SYSTEMIC ADVERSE EFFECTS. Principal Investigator: Arnis Richters, Ph.D. School of Medicine Los Angeles, CA. 1986. A4-064-33.

EFFECTS OF OZONE ON THE ASTHMATIC AIRWAY. Principal Investigator: J. A. Nadel, M. D. University of California, San Francisco. 1985. A3-112-33.

HEALTH EFFECTS FROM THE INHALATION OF OXIDANT AIR POLLUTANTS AS RELATED TO THE IMMUNE SYSTEM. Principal Investigator: John W. Osebold. University of California, Davis. 1985. A2-057-33.

THE INFLUENCE OF EXERCISE ON LUNG INJURY INDUCED BY OZONE AND NITROGEN DIOXIDE. Principal Investigator: William J. Mautz, Ph.D.University of California, Irvine. 1984. A2-129-33.

THE EFFECTS OF HEAVY SUSTAINED EXERCISE IN COMBINATION WITH LOW LEVELS OF OZONE CONCENTRATION IN INDUCING ACUTE PULMONARY FUNCTION IMPAIRMENT IN HUMANS: INTERACTION OF AMBIENT HEAT AND MULTIPLE POLLUTANT EXPOSURES. Principal Investigator: William C. Adams, Ph.D. University of California, Davis. 1984. A1-158-33.

HEALTH EFFECTS FROM THE INHALATION OF OXIDANT AIR POLLUTANTS AS RELATED TO THE IMMUNE SYSTEM. Principal Investigator: John W. Osebold. University of California, Davis. 1983. A1-054-32.

AIRWAY RESPONSES TO ATMOSPHERIC POLLUTANTS: SULFUR DIOXIDE AND OZONE. Principal Investigator: J. A. Nadel, M. D. University of California, San Francisco. 1983. A1-133-33.

OZONE TOXICITY EFFECTS CONSEQUENT TO PROLONGED, HIGH INTENSITY EXERCISE IN TRAINED ENDURANCE ATHLETES. Principal Investigator: William C. Adams, Ph.D. and Edward S. Schelegle, M. A. University of California, Davis. 1982. A0-078-32.

EFFECTS OF OZONE INHALATION DURING EXERCISE ON SELECTED HEART DISEASE PATIENTS. Principal Investigator: H. Robert Superko, M. D. University of California, Davis. 1981. A8-120-31.

HEALTH EFFECTS FROM THE INHALATION OF OXIDANT AIR POLLUTANTS AS RELATED TO THE IMMUNE SYSTEM. Principal Investigator: John W. Osebold. University of California, Davis. 1981. A7-179-30, A8-122-31, and A9-145-31.

AIRWAY HYPERIRRITABILITY INDUCED BY OZONE. Principal Investigator: J. A. Nadel, M. D. University of California, San Francisco. 1979. A8-053-30.

AIRWAY HYPERIRRITABILITY INDUCED BY OZONE. Principal Investigator: J. A. Nadel, M. D. University of California, San Francisco. 1978. A6-215-30.

DEVELOPMENT OF A BIOLOGICAL TEST SYSTEM FOR QUANTITATING THE RESPIRATORY HAZARD OF AMBIENT CONCENTRATIONS OF AIR POLLUTANTS AND EVALUATION OF VITAMIN E IN THE PREVENTION OF OXIDANT INDUCED IMPAIRMENT. Principal Investigator: Elliot Goldstein, M. D. University of California, Davis. 1977. 7-077-1.

HEALTH EFFECTS OF OZONE EXPOSURE IN ASTHMATICS. Principal Investigator: Jack D, Hackney, M. D. Rancho Los Amigos Hospital Inc. 1975. 4-191.

Particulate Matter

POLYCYCLIC AROMATIC HYDROCARBONS (PAHs): SOURCES OF AMBIENT QUINONES. Principal Investigator: Janet Arey and Roger Atkinson. University of California, Riverside. 2007. 03-314.

DEVELOPMENT AND APPLICATION OF AMBIENT AEROSOL CONCENTRATORS TO CONDUCT HEALTH EFFECTS STUDIES IN THE LOS ANGELES BASIN. Principal Investigator: John R. Froines. University of California, Los Angeles. 2006. 98-316

MECHANISMS OF PARTICULATE TOXICITY: HEALTH EFFECTS IN SUSCEPTIBLE HUMANS. Principal Investigator: Colin Solomon, Ph.D. University of California, San Francisco. 2004. 99-314

MECHANISMS OF PARTICULATE TOXICITY: EFFECTS ON THE RESPIRATORY SYSTEM OF SENSITIVE ANIMALS AND ASTHMATIC HUMANS. Principal Investigator: KENT E. PINKERTON, Ph.D. University of California, Davis. 2004. 99-315

MECHANISMS OF PARTICULATE TOXICITY: EFFECTS ON THE RESPIRATORY SYSTEM OF SENSITIVE ANIMALS AND ASTHMATIC HUMANS. Principal Investigator: M. T. KLEINMAN, Ph.D. University of California, Irvine. 2004. 99-316

REVIEW OF SOURCE APPORTIONMENT TECHNIQUES FOR AIRBORNE PARTICULATE MATTER. Principal Investigator: Michael. J. Kleeman. University of California, Davis. 2003. 00-332

A CRITICAL REVIEW OF THE PARTICULATE MATTER TOXICOLOGY LITERATURE FOR SENATE BILL 25 REVIEW OF THE PARTICULATE MATTER STANDARD.  Principal Investigator: Kent E. Pinkerton, Ph.D. University of California, Davis. 2002. 00-327.

HEALTH EFFECTS OF PM COMPONENTS ON SENSITIVE ANIMAL MODELS.  Principal Investigator: M. T. Kleinman, Ph.D. University of California, Irvine. 2002. 96-311.

objectives:  To examine the mechanisms of short-term particulate damage on cells that line the respiratory tracts of adult and old rats upon exposure to varying sizes of particulate matter for varying lengths of time.

Importance to ARB’s Program: Results from this study will augment current epidemiology findings concerning the relationships between health effects and particulate matter exposure by determining the mechanisms of cellular damage.

PARTICULATE AIR POLLUTION AND MORBIDITY IN THE CALIFORNIA CENTRAL VALLEY: A HIGH PARTICULATE POLLUTION REGION. Principal Investigator: Stephen K. Van Den Eeden, Ph.D. Kaiser Permanente, Northern California Region. 2002. 97-303.

DEVELOPMENT OF AN EXPOSURE FACILITY TO CONDUCT INHALATION STUDIES TO AMBIENT AEROSOLS.  Principal Investigator: John R. Froines, Ph.D., University of California, Los Angeles. 2000. 98-316.

Objective: The objective of this project is to construct and test the performance of a facility designed to create test atmospheres by separating and containing particles from ambient air at specified concentrations.

Importance to ARB’s Program: The variability of ambient air in an uncontrolled environment makes it difficult to accurately determine what impact particles in urban air have on human health.  The development of this exposure facility will provide a controlled environment for both human and animal exposure studies.  The ARB will then be able to investigate the mechanisms of injury and pollutant interaction.  It will also be possible to assess the importance of particle size and chemistry on health outcomes.  This will be the first facility of its kind in California.

MECHANISMS OF PARTICULATE TOXICITY: EXPOSURE EFFECTS ON THE RESPIRATORY SYSTEM. Principal Investigator: Kent E. Pinkerton Ph.. University of California, Davis. 2000. 96-310.

objectives: To examine the mechanisms of short-term particulate damage on cells that line the respiratory tracts of adult, young, and old rats upon exposure to varying concentrations of PM10 for varying lengths of time.

Importance to ARB's Program: Results from this study will augment current epidemiology findings concerning the relationship between health effects and particulate matter exposure by determining the mechanisms of cellular damage

PROCEEDINGS OF THE THIRD COLLOQUIUM ON PARTICULATE AIR POLLUTION AND HUMAN HEALTH. Principal Investigator: Robert Phalen. University of California, Irvine. 1999. 98-332.

ALLERGENS IN PAVED ROAD DUST AND AIRBORNE PARTICLES. Principal Investigator: Glen Cass. California Institute of Technology, Pasadena, California. 1998. 95-312.

objectives: To detect, characterize and compare the main allergens found in both paved road dust and ambient air PM10 samples and to estimate paved road dust contributions to PM10 ambient levels.

Findings: At least 25 different allergens were found in the paved road dust and ambient particle samples analyzed, including pollen, pollen fragments, animal dander, and molds. Five to 13 percent of the total allergenicity of atmospheric particulate matter found in urban areas of Long Beach and Rubidoux was directly attributable to paved road dust emissions. The allergenic content of particles collected in the industrial area of central Los Angeles, which has little or no proximity to vegetation and domestic activities, was much lower, on the order of only 0.5%. Using chemical speciation techniques and mass balance modeling, the investigators estimated that 26-33% of the airborne PM10 samples and 36-64% of the total suspended particulate samples were composed of paved road dust. Three to nine percent of the road dust material was found to be around 2 micrometers in aerodynamic diameter.

Importance to ARB's Program: The results of this study will provide an understanding of the importance of paved road dust in creating PM10 and will aid in the overall understanding of the role of particulate air pollution in respiratory disease.

TOXICITY OF CHEMICAL CONSTITUENTS OF PM10 IN THE SOUTH COAST AIR BASIN OF CALIFORNIA. Principal Investigator: DRS. William Mautz & Michael Kleinm. University of California, Irvine. 1997. 93-318.

objectives: To evaluate animal responses to inhalation of particulate matter (PM) mixtures of various compositions and concentrations that reflect ambient PM levels found in California and which are suspected of being toxic in humans.

Findings: This study consistently showed that exposure to PM (composed of elemental carbon and ammonium bisulfate) delivered under well controlled conditions caused measurable and perhaps biologically significant injury to lung cells. The study also showed that PM exposure caused functional depression of an important component -- macrophage cells -- of the lung's natural immune system defenses. The study also showed that the effects of PM exposure are amplified by the presence of ozone. This suggests that previous controlled exposure studies that examined only single pollutants may have underestimated the health effects of PM pollution.

Importance to ARB's Program: Epidemiological evidence indicates that particulate matter air pollution is associated with increased incidence of mortality and morbidity among people living in polluted urban areas. Development of good control strategies to reduce the health risk from PM10 requires determination of the relative toxic potentials of its various components, with regard to both their chemical nature and their size distribution.

THE SECOND COLLOQUIUM ON PARTICULATE AIR POLLUTION AND HUMAN HEALTH AND MORBIDITY. Principal Investigator: DR. Robert Phalen. University of California, Irvine. 1997. 95-323.

objectives: To hold a meeting of health experts to present and discuss the findings of research conducted to determine the health effects of particulate matter (PM) pollution and statistical methods for determining the properties of PM that may relate to the observed effects.

Findings: The meeting was attended by approximately 300 scientists and others interested in the regulatory aspects of PM. It was a valuable means for moving forward the state of air pollution science as it relates to the health effects of PM. The meeting sharpened the issues and several even larger meetings on the issues followed.

Importance to ARB's Program: The information presented at this and the following meetings was useful in reviews of PM regulatory actions taken by the U.S. EPA, which was a principal co-sponsor of the meeting.

COLLOQUIUM ON PARTICULATE AIR POLLUTION AND HUMAN MORTALITY AND MORBIDITY. University of California, Irvine.1995. 92-341.

objectives: To conduct a scientific meeting to discuss the recently reported statistical associations between ambient levels of particulate matter (PM10) and human mortality and/or morbidity. Although several investigators have linked an increase in death rates and respiratory infections with day-to-day changes in ambient levels of PM10, the cause/effect relationships and the contributory role of specific components of PM10 need to be explored more fully.

Findings: The meeting was held as scheduled January 24-25, 1994, at the Arnold and Mabel Beckman Center of the National Academies of Sciences and Engineering in Irvine, California. The colloquium was very well attended. The topics and issues discussed set the stage for future particulate matter research. The papers and abstracts from the colloquium can be found in two special issues of the journal Inhalation Toxicology: Vols. 7(1) and 7(5).

Importance to ARB's Program: The discussions that took place at this meeting will provide a platform for scientists to clarify the issues related to a) the degree to which life span may be affected; b) the population subgroups that are at increased risk at ambient levels of PM10; and c) the suitability of biostatistical methods used to analyze and refine PM10-related mortality and morbidity changes. These discussions are the first step in the ARB's scheduled review of the State's ambient air quality standard for PM10 and will help identify future research projects enabling the ARB to place the standard on a firmer scientific base.

TOXICITIES OF CHEMICAL CONSTITUENTS OF PM10 IN THE SOUTH COAST AIR BASIN IN CALIFORNIA. Principal Investigator: D. K. Bhalla, Ph.D University of California, Irvine.1993. A933-158.

objectives: To determine relative toxicities of various chemical constituents of fine particulate matter (PM10) found in the South Coast Air Basin.

Findings: Changes in responses (airway permeability, immune functions, and mucus secretion) that are associated with disease processes were observed in rats exposed to sulfates, nitrates, and road dust. These substances are major constituents of PM10.

Importance to ARB's Program: This was the first study conducted in the United States to evaluate the relative toxicities of PM10 components. It provided insight into types of studies required in the future to address the issue in more detail.

EFFECTS OF INHALED PARTICULATE MATTER. Principal Investigator: Otto G. Raabe, Ph.D. University of California, Davis. 1989. A4-133-33.

PILOT INVESTIGATION OF INDOOR - OUTDOOR AND PERSONAL PM10 (THORACIC) AND ASSOCIATED IONIC COMPOUNDS AND MUTAGENIC ACTIVITY. Principal Investigator: Steven D.Colome. University of California, Irvine. 1989. A6-129-33.

objectives: To test sampling equipment and methods for measuring indoor and personal exposures to respirable particles (PM10) and particle constituents and properties relevant to assessing health effects.

Findings:  Different types of sampling equipment were tested in the laboratory and inside and outside ten southern California homes of asthmatics. This study successfully demonstrated the feasibility of monitoring indoor and personal exposures to particles and their constituents in a large field study.

Importance to ARB’s Program: This study helped set the stage for conducting a large-scale residential particle study (called PTEAM) co-funded by ARB and U.S. EPA (A933-144, 1992).

CHRONIC RESPIRATORY DISEASE SYMPTOM EFFECTS OF LONG - TERM CUMULATIVE EXPOSURE TO AMBIENT LEVELS OF TOTAL SUSPENDED PARTICULATE (TSP), TOTAL OXIDANTS, SULFUR DIOXIDE AND NITROGEN DIOXIDE IN CALIFORNIA. Principal Investigator: David E. Abbey, Ph.D. Loma Linda University. 1985. A013032, A7-176-30, and a8-147-31.

DEPOSITION OF PARTICLES IN CHILDREN'S LUNGS. Principal Investigator: Robert F. Phalen, Ph.D. University of California, Irvine. 1985. A0-128-32.