James Sadd

Environmental Justice and Southern California’s “Riskscape” The Distribution of Air Toxics Exposures and Health Risks among Diverse Communities

Past research on “environmental justice” has often failed to systematically link hazard proximity with quantifiable health risks. The authors employ recent advances in air emissions inventories and modeling techniques to consider a broad range of outdoor air toxics in Southern California and to calculate the potential lifetime cancer risks associated with these pollutants. They find that such risks are attributable mostly to transportation and small-area sources and not the usually targeted large-facility pollution emissions. Multivariate regression suggests that race plays an explanatory role in risk distribution even after controlling for other economic, land-use, and population factors. This pattern suggests the need for innovative emissions reduction efforts as well as specific strategies to alter the spatial and racial character of the environmental “riskscape” in urban centers.

The Air is Always Cleaner on the Other Side: Race, Space, and Ambient Air Toxics Exposures in California

ABSTRACT: Environmental justice advocates have recently focused attention on cumulative exposure in minority neighborhoods due to multiple sources of pollution. This article uses U.S. EPA’s National Air Toxics Assessment (NATA) for 1996 to examine environmental inequality in California, a state that has been a recent innovator in environmental justice policy. We first estimate potential lifetime cancer risks from mobile and stationary sources. We then consider the distribution of these risks using both simple comparisons and a multivariate model in which we control for income, land use, and other explanatory factors, as well as spatial correlation. We find large racial disparities in California’s “riskscape” as well as inequalities by other factors and suggest several implications for environmental and land use policy.

“Every Breath You Take... ”: The Demographics of Toxic Air Releases in Southern California

In this article, the authors investigate the relationship between ethnicity and potential environmental hazards in the metropolitan Los Angeles area. Using a variety of techniques, including geographic information systems (GIS) mapping, univariate comparisons, and logit, ordered logit, and tobit regression analysis, the authors find that, even controlling for other factors such as income and the extent of manufacturing employment and land use, minority residents tend to be disproportionately located in neighborhoods surrounding toxic air emissions. The results generally support the propositions of the proponents of “environmental justice”; in the conclusion, they consider what this might mean for urban land use and environmental policy.

Ambient air pollution exposure and full-term birth weight in California

BackgroundStudies have identified relationships between air pollution and birth weight, but have been inconsistent in identifying individual pollutants inversely associated with birth weight or elucidating susceptibility of the fetus by trimester of exposure. We examined effects of prenatal ambient pollution exposure on average birth weight and risk of low birth weight in full-term births.MethodsWe estimated average ambient air pollutant concentrations throughout pregnancy in the neighborhoods of women who delivered term singleton live births between 1996 and 2006 in California. We adjusted effect estimates of air pollutants on birth weight for infant characteristics, maternal characteristics, neighborhood socioeconomic factors, and year and season of birth.Results3,545,177 singleton births had monitoring for at least one air pollutant within a 10 km radius of the tract or ZIP Code of the mothers residence. In multivariate models, pollutants were associated with decreased birth weight; -5.4 grams (95% confidence interval -6.8 g, -4.1 g) per ppm carbon monoxide, -9.0 g (-9.6 g, -8.4 g) per pphm nitrogen dioxide, -5.7 g (-6.6 g, -4.9 g) per pphm ozone, -7.7 g (-7.9 g, -6.6 g) per 10 μ g/m3 particulate matter under 10 μm, -12.8 g (-14.3 g, -11.3 g) per 10 μ g/m3 particulate matter under 2.5 μm, and -9.3 g (-10.7 g, -7.9 g) per 10 μ g/m3 of coarse particulate matter. With the exception of carbon monoxide, estimates were largely unchanged after controlling for co-pollutants. Effect estimates for the third trimester largely reflect the results seen from full pregnancy exposure estimates; greater variation in results is seen in effect estimates specific to the first and second trimesters.ConclusionsThis study indicates that maternal exposure to ambient air pollution results in modestly lower infant birth weight. A small decline in birth weight is unlikely to have clinical relevance for individual infants, and there is debate about whether a small shift in the population distribution of birth weight has broader health implications. However, the ubiquity of air pollution exposures, the responsiveness of pollutant levels to regulation, and the fact that the highest pollution levels in California are lower than those regularly experienced in other countries suggest that precautionary efforts to reduce pollutants may be beneficial for infant health from a population perspective.

Who's Minding the Kids? Pollucion, Public Schools, and Environmental Justice in Los Angeles

Objective. Although previous environmental justice research has focused on analysis of the disproportionate burden of environmental hazards on minority residents, few studies have examined demographic inequities in health risks among children. This article evaluates the demographic distribution of potentially hazardous facilities and health risks associated with ambient air toxics exposures among public schoolchildren in the Los Angeles Unified School District. Methods. We combine Geographic Information System analysis with multivariate statistics to compare enrollment and demographic information for students who attend district schools with the spatial pattern of land use, locations of toxic emissions and facilities, and calculated indices of estimated lifetime cancer risk and respiratory hazards associated with exposures to toxic air emissions. Results. District schools are more likely to be located in census tracts containing potentially hazardous facilities; however, these tracts actually have slightly lower cancer and respiratory health risks associated with air toxics when compared to other tracts in the district. Demographic comparisons among school sites indicate that minority students, especially Latinos, are more likely to attend schools near hazardous facilities and face higher health risks associated with outdoor air toxics exposure. Conclusions. These patterns of hazard exposure and health risk should be considered both in the process of siting new schools to house the rapidly growing regional student population and in remediation efforts at existing schools.

Playing It Safe: Assessing Cumulative Impact and Social Vulnerability through an Environmental Justice Screening Method in the South Coast Air Basin, California

Regulatory agencies, including the U.S. Environmental Protection Agency (US EPA) and state authorities like the California Air Resources Board (CARB), have sought to address the concerns of environmental justice (EJ) advocates who argue that chemical-by-chemical and source-specific assessments of potential health risks of environmental hazards do not reflect the multiple environmental and social stressors faced by vulnerable communities. We propose an Environmental Justice Screening Method (EJSM) as a relatively simple, flexible and transparent way to examine the relative rank of cumulative impacts and social vulnerability within metropolitan regions and determine environmental justice areas based on more than simply the demographics of income and race. We specifically organize 23 indicator metrics into three categories: (1) hazard proximity and land use; (2) air pollution exposure and estimated health risk; and (3) social and health vulnerability. For hazard proximity, the EJSM uses GIS analysis to create a base map by intersecting land use data with census block polygons, and calculates hazard proximity measures based on locations within various buffer distances. These proximity metrics are then summarized to the census tract level where they are combined with tract centroid-based estimates of pollution exposure and health risk and socio-economic status (SES) measures. The result is a cumulative impacts (CI) score for ranking neighborhoods within regions that can inform diverse stakeholders seeking to identify local areas that might need targeted regulatory strategies to address environmental justice concerns.

Reading, Writing, and Toxics: Children's Health, Academic Performance, and Environmental Justice in Los Angeles

A significant body of previous research on environmental justice has demonstrated a disproportionate burden of environmental hazards on low-income and minority residents. In this paper we evaluate spatially indexed data on estimated respiratory and cancer risks associated with exposures to ambient air toxics to show that children of color in the Los Angeles Unified School District suffer potentially disparate health impacts, and that disparities in environmental risks may be associated with diminished school performance—even after controlling for socioeconomic and demographic covariates that generally explain much of the variation in student scores. Remediating environmental health risks in distressed neighborhoods could, therefore, improve both health and human capital.

Integrating Environmental Justice and the Precautionary Principle in Research and Policy Making: The Case of Ambient Air Toxics Exposures and Health Risks among Schoolchildren in Los Angeles

Two policy frameworks, environmental justice and the precautionary principle, have begun to transform traditional approaches to environmental policy making and community organizing related to public health. Despite having several important overlapping policy goals, little effort has been made to purposefully integrate these two frameworks. This article discusses preliminary research on environmental inequality in ambient air toxics exposures and associated health risks among schoolchildren in the Los Angeles Unified School District. Results indicate that children of color, namely, Latinos and African Americans, bear the highest burden of estimated cancer and noncancer health risks associated with ambient air toxics exposures while they are in school. The implications of these study results for controversial policy decisions related to school siting and construction in urban districts are discussed within the context of environmental justice and the precautionary principle.

The Truth, the Whole Truth, and Nothing but the Ground-Truth: Methods to Advance Environmental Justice and Researcher–Community Partnerships

Environmental justice advocates often argue that environmental hazards and their health effects vary by neighborhood, income, and race. To assess these patterns and advance preventive policy, their colleagues in the research world often use complex and methodologically sophisticated statistical and geospatial techniques. One way to bridge the gap between the technical work and the expert knowledge of local residents is through community-based participatory research strategies. We document how an environmental justice screening method was coupled with “ground-truthing”—a project in which community members worked with researchers to collect data across six Los Angeles neighborhoods—which demonstrated the clustering of potentially hazardous facilities, high levels of air pollution, and elevated health risks. We discuss recommendations and implications for future research and collaborations between researchers and community-based organizations.

Holocene marine cement coatings on beach-rocks of the Abu Dhabi coastline (UAE); Analogs for cement fabrics in ancient limestones

Marine carbonate cements, which are superficially like travertines from meteoric caves, are coating and binding some intertidal sedimentary rock surfaces occurring in coastal Abu Dhabi, the United Arab Emirates, (UAE). Near Jebel Dhana these surficial cements can be up to 3 cm thick and envelope beach rock surfaces and fossils. They are also present both as thin coats and a fracture-fill cement in the intertidal hard grounds associated with the Khor Al Bazam algal flats.The thickness, microscopic characteristics, and morphology of the marine cement coatings from Jebel Dhana indicates incremental deposition of aragonite in conjunction with traces of sulfate minerals. Most of these cement coatings are micritic, but the layers which encrust the hard grounds from the algal flat of the Khor al Bazam have a more radial and fibrous micro-structure and are composed solely of aragonite.The stable isotopic composition of coatings from Jebel Dhana (δ18O = +0.35, δ13C = +4.00) falls within the compositional range for modern marine non skeletal aragonite and suggests that the marine travertine-like cements precipitate from the agitated, slightly hypersaline Arabian Gulf’ sea water during repeated cycles of exposure, evaporation and immersion.Similar cement coatings and microfabrics are present in the tepee structured and brecciated sediments of the Guadalupe Mountains (Permian) and the Italian Alps (Triassic), in Holocene algal head cements from the Great Salt Lake, and in similar Tertiary algal heads in the Green River Formation of the western US. The petrographic similarity of these ancient “flow stone” like cements with Recent hypersaline marine cement coatings suggests that high rates of carbonate cementation and hypersaline conditions contribute to tepee formation and cavity fill.