Traffic Impacts on PM(2.5) Air Quality in Nairobi, Kenya.

Motor vehicle traffic is an important source of particulate pollution in cities of the developing world, where rapid growth, coupled with a lack of effective transport and land use planning, may result in harmful levels of fine particles (PM(2.5)) in the air. However, a lack of air monitoring data hinders health impact assessments and the development of transportation and land use policies that could reduce health burdens due to outdoor air pollution. To address this important need, a study of traffic-related PM(2.5) was carried out in the city of Nairobi, Kenya, a model city for sub-Saharan Africa, in July 2009. Sampling was carried out using portable filter-based air samplers carried in backpacks by technicians on weekdays over two weeks at several sites in and around Nairobi ranging from high-traffic roadways to rural background. Mean daytime concentrations of PM(2.5) ranged from 10.7 at the rural background site to 98.1 µg/m(3) on a sidewalk in the central business district. Horizontal dispersion measurements demonstrated a decrease in PM(2.5) concentration from 128.7 to 18.7 µg/m(3) over 100 meters downwind of a major intersection in Nairobi. A vertical dispersion experiment revealed a decrease from 119.5 µg/m(3) at street level to 42.8 µg/m(3) on a third-floor rooftop in the central business district. Though not directly comparable to air quality guidelines, which are based on 24-hour or annual averages, the urban concentrations we observed raise concern with regard to public health and related policy. Taken together with survey data on commuting patterns within Nairobi, these results suggest that many Nairobi residents are exposed on a regular basis to elevated concentrations of fine particle air pollution, with potentially serious long-term implications for health.

Links between the built environment, climate and population health: interdisciplinary environmental change research in New York City.

Global climate change is expected to pose increasing challenges for cities in the following decades, placing greater stress and impacts on multiple social and biophysical systems, including population health, coastal development, urban infrastructure, energy demand, and water supplies. Simultaneously, a strong global trend towards urbanisation of poverty exists, with increased challenges for urban populations and local governance to protect and sustain the wellbeing of growing cities. In the context of these 2 overarching trends, interdisciplinary research at the city scale is prioritised for understanding the social impacts of climate change and variability and for the evaluation of strategies in the built environment that might serve as adaptive responses to climate change. This article discusses 2 recent initiatives of The Earth Institute at Columbia University (EI) as examples of research that integrates the methods and objectives of several disciplines, including environmental health science and urban planning, to understand the potential public health impacts of global climate change and mitigative measures for the more localised effects of the urban heat island in the New York City metropolitan region. These efforts embody 2 distinct research approaches. The New York Climate & Health Project created a new integrated modeling system to assess the public health impacts of climate and land use change in the metropolitan region. The Cool City Project aims for more applied policy-oriented research that incorporates the local knowledge of community residents to understand the costs and benefits of interventions in the built environment that might serve to mitigate the harmful impacts of climate change and variability, and protect urban populations from health stressors associated with summertime heat. Both types of research are potentially useful for understanding the impacts of environmental change at the urban scale, the policies needed to address these challenges, and to train scholars capable of collaborative approaches across the social and biophysical sciences.

Oral health and health care for older adults: a spatial approach for addressing disparities and planning services.

The purpose of this paper was to examine the geographic distribution of New York City adults aged 65 and older by race/ethnicity and poverty status. Also analyzed was seniors' access to dental care as defined by the location of dental providers and their proximity to the subway system lines in Manhattan and the Bronx. ArcGIS software was used to create a geographic information system (GIS) incorporating relevant data from a variety of sources. Individual and overlay maps were then produced to examine the aims of this analysis. Data showed that Black race, Hispanic ethnicity, and poverty status tend to co-occur spatially among seniors in Northern Manhattan and the South Bronx. Further, a spatial/transportation barrier may inhibit access to dental care for seniors who reside in these areas. By presenting multiple layers of local information juxtaposed, GIS can help provide directions for planning oral health service delivery for seniors.

A joint urban planning and public health framework: contributions to health impact assessment.

A joint urban planning and public health perspective is articulated here for use, in health impact assessment. Absent a blueprint for a coherent and supportive structure on which to test our thinking, we are bound to fall flat. Such a perspective is made necessary by the sheer number of people living in cities throughout the world, the need for explicit attention to land use and transportation systems as determinants of population health, and the dearth of useful indicators of the built environment for monitoring progress. If explicit attention is not paid to the overarching goals of equality and democracy, they have little if any chance of being realized in projects, programs, and policies that shape the built environment and therefore the public's health.

Sorting out the connections between the built environment and health: a conceptual framework for navigating pathways and planning healthy cities.

The overarching goal of this article is to make explicit the multiple pathways through which the built environment may potentially affect health and well-being. The loss of close collaboration between urban planning and public health professionals that characterized the post-World War II era has limited the design and implementation of effective interventions and policies that might translate into improved health for urban populations. First, we present a conceptual model that developed out of previous research called Social Determinants of Health and Environmental Health Promotion. Second, we review empirical research from both the urban planning and public health literature regarding the health effects of housing and housing interventions. And third, we wrestle with key challenges in conducting sound scientific research on connections between the built environment and health, namely: (1) the necessity of dealing with the possible health consequences of myriad public and private sector activities; (2) the lack of valid and reliable indicators of the built environment to monitor the health effects of urban planning and policy decisions, especially with regard to land use mix; and (3) the growth of the "megalopolis" or "super urban region" that requires analysis of health effects across state lines and in circumscribed areas within multiple states. We contend that to plan for healthy cities, we need to reinvigorate the historic link between urban planning and public health, and thereby conduct informed science to better guide effective public policy.