Community-Based Participatory Research and Policy Advocacy to Reduce Diesel Exposure in West Oakland, California

摘要

We conducted a multimethod case study analysis of a community-based participatory research partnership in West Oakland, California, and its efforts to study and address the neighborhood's disproportionate exposure to diesel air pollution. We employed 10 interviews with partners and policymakers, participant observation, and a review of documents. Results of the partnership's truck count and truck idling studies suggested substantial exposure to diesel pollution and were used by the partners and their allies to make the case for a truck route ordinance. Despite weak enforcement, the partnership's increased political visibility helped change the policy environment, with the community partner now heavily engaged in environmental decision-making on the local and regional levels. Finally, we discussed implications for research, policy, and practice. Located on the San Francisco Bay, and bounded by freeways, West Oakland is a small but vibrant community of predominately low-income African American and Latino residents. Home to nearly 22 000 people in 10 distinct neighborhoods, the community also contains thousands of moving and stationary sources of diesel pollution. 1 From the buses and trucks on surrounding freeways, to the container trucks moving through neighborhoods as they take goods to and from the Port of Oakland and a major US Post Office distribution center, residents have long experienced disproportionate exposure to diesel exhaust and traffic-related air pollutants. Although such exposures are known to adversely affect cardiovascular health outcomes, including premature mortality, 2 – 4 of greatest concern to West Oakland residents is the role of these pollutants in exacerbating asthma and related respiratory conditions in children and their families. Recent prospective studies have shown a positive relationship between traffic-related air pollution and the onset of asthma in children, 5 as well as adverse effects of such exposure on the growth of lung functioning in children aged 10–18 years. 6 In a nested case–control study in British Columbia, Canada, elevated exposure to traffic-related air pollutants, such as nitrogen dioxide, carbon monoxide, and black carbon, in utero or in infancy was also recently found to be associated with higher risk of asthma in children under age 5. 7 In many low income urban neighborhoods, and particularly communities such as West Oakland with major “goods movement” activity related to international trade, a larger than normal percentage of traffic consists of diesel trucks, 8 including those moving containers. 9 The emissions from diesel exhaust are a combination of gases and particles, including a high number of ultrafine particles shown to be especially hazardous because they can escape many of the body's defenses, allowing them to enter the lungs and the systemic circulation. 10 Although automobile emissions also include ultrafine particulate matter, for residents of West Oakland, who see relatively little car traffic in the neighborhood itself but regularly find diesel exhaust soot on their window sills and heating vents from the high volume of truck traffic, diesel air pollution is of far greater local concern. In West Oakland, as in a growing number of low income communities disproportionately impacted by environmental hazards, community-based participatory research (CBPR) has been used by local residents, in partnership with outside researchers, to help study and address neighborhood challenges, while building local capacity. 11 – 19 Green et al 20 defined CBPR as “systematic inquiry, with the participation of those affected by the issue being studied, for the purposes of education and taking action or effecting change.” Among the core principles of this approach to research are that it recognizes community as a unit of identity; it entails an empowering, colearning process that “equitably” involves all partners; and it includes systems development and increases local problem-solving ability. It also achieves a balance of research and action, and “involves a long term process and a commitment to sustainability.” 21 Finally, CBPR pays serious attention to issues of research rigor and validity. However, it also “broadens the bandwidth of validity” 22 to ask whether the research question is “valid,” in the sense of coming from or being meaningful to the involved community. With its commitment to action as part of the research process itself, CBPR has increasingly been utilized by community–academic partnerships interested in using their research findings, together with advocacy and organizing, to help move policy that may improve conditions and environments in which people can be healthy. 17 , 19 Our primary research goal was to analyze a CBPR partnership between a community-led and -based organization, the Wes