Developing a granular scale environmental burden index (EBI) for diverse land cover types across the contiguous United States.

Critical to identifying the risk of environmentally driven disease is an understanding of the cumulative impact of environmental conditions on human health. Here we describe the methodology used to develop an environmental burden index (EBI). The EBI is calculated at U.S. census tract level, a finer scale than many similar national-level tools. EBI scores are also stratified by tract land cover type as per the National Land Cover Database (NLCD), controlling for urbanicity. The EBI was developed over the course of four stages: 1) literature review to identify potential indicators, 2) data source acquisition and indicator variable construction, 3) index creation, and 4) stratification by land cover type. For each potential indicator, data sources were assessed for completeness, update frequency, and availability. These indicators were: (1) particulate matter (PM2.5), (2) ozone, (3) Superfund National Priority List (NPL) locations, (4) Toxics Release Inventory (TRI) facilities, (5) Treatment, Storage, and Disposal (TSD) facilities, (6) recreational parks, (7) railways, (8) highways, (9) airports, and (10) impaired water sources. Indicators were statistically normalized and checked for collinearity. For each indicator, we computed and summed percentile ranking scores to create an overall ranking for each tract. Tracts having the same plurality of land cover type form a 'peer' group. We re-ranked the tracts into percentiles within each peer group for each indicator. The percentile scores were combined for each tract to obtain a stratified EBI. A higher score reveals a tract with increased environmental burden relative to other tracts of the same peer group. We compared our results to those of related indices, finding good convergent validity between the overall EBI and CalEnviroScreen 4.0. The EBI has many potential applications for research and use as a tool to develop public health interventions at a granular scale.

Landscape disturbance impacts on Attalea butyracea palm distribution in central Panama.

BACKGROUND: Increased Attalea butyracea palm propagation, notable for its role as key habitat for the primary Chagas disease vector in Panama, has been linked to landscape disturbance in single-palm observations in this region. Close proximity of these palms to human dwellings is proposed to increase risk of Chagas disease transmission from sylvatic transmission cycles to domestic transmission involving human populations. This study examines the relationship between landscape disturbance and mature A. butyracea spatial distribution, density, and proximity to human populations and vector and reservoir species' movement corridors at a regional scale in a 300 km2 heterogeneous tropical landscape in central Panama. METHODS: We remotely identified the locations of over 50,000 mature A. butyracea palms using high-resolution WorldView2 satellite imagery. A local Getis-Ord Gi* spatial analysis identified significant clusters of aggregated palms. Associations between palm and cluster abundance and a landscape disturbance gradient, derived from official Panama land cover data, were tested using Chi-square tests for Homogeneity and Z-test for proportions. Kruskall-Wallis non-parametric analysis of variance tests were run to assess whether palm cluster area varied by disturbance level, or whether disturbance was associated with proximity of palms and palm clusters to susceptible populations or vector movement corridors. RESULTS: Our findings indicate a regional relationship between landscape disturbance and A. butyracea occurrence. We observe a significant increase in both individual and clustered A. butyracea in secondary forest, but a reduction of palms in agricultural settings. We do not detect evidence of any reduction in abundance of palms in residential settings. The majority of residential and commercial buildings in our study area are within vector flight distance of potential vector habitat in palm crowns. CONCLUSIONS: We observe probable anthropogenic elimination of A. butyracea palms in agricultural, but not residential, settings. Even in heavily deforested regions, significant concentrations of mature palms remain in close proximity to human establishments.

Injuries and post-traumatic stress following historic tornados: Alabama, April 2011.

OBJECTIVES: We analyzed tornado-related injuries seen at hospitals and risk factors for tornado injury, and screened for post-traumatic stress following a statewide tornado-emergency in Alabama in April 2011. METHODS: We conducted a chart abstraction of 1,398 patients at 39 hospitals, mapped injured cases, and conducted a case-control telephone survey of 98 injured cases along with 200 uninjured controls. RESULTS: Most (n = 1,111, 79.5%) injuries treated were non-life threatening (Injury Severity Score ≤ 15). Severe injuries often affected head (72.9%) and chest regions (86.4%). Mobile home residents showed the highest odds of injury (OR, 6.98; 95% CI: 2.10-23.20). No severe injuries occurred in tornado shelters. Within permanent homes, the odds of injury were decreased for basements (OR, 0.13; 95% CI: 0.04-0.40), bathrooms (OR, 0.22; 95% CI: 0.06-0.78), hallways (OR, 0.31; 95% CI: 0.11-0.90) and closets (OR, 0.25; 95% CI: 0.07-0.80). Exposure to warnings via the Internet (aOR, 0.20; 95% CI: 0.09-0.49), television (aOR, 0.45; 95% CI: 0.24-0.83), and sirens (aOR, 0.50; 95% CI: 0.30-0.85) decreased the odds of injury, and residents frequently exposed to tornado sirens had lower odds of injury. The prevalence of PTSD in respondents was 22.1% and screening positive for PTSD symptoms was associated with tornado-related loss events. CONCLUSIONS: Primary prevention, particularly improved shelter access, and media warnings, seem essential to prevent severe tornado-injury. Small rooms such as bathrooms may provide some protection within permanent homes when no underground shelter is available.

Mortality from a tornado outbreak, Alabama, April 27, 2011.

OBJECTIVES: We describe the demographics of the decedents from the tornado outbreak in Alabama on April 27, 2011; examine the circumstances of death surrounding these fatalities; and identify measures to prevent future tornado-related fatalities. METHODS: We collected information about the decedents from death certificates, disaster-related mortality surveillance, and interview data collected by American Red Cross volunteers from the decedent's families. We describe demographic characteristics, circumstances and causes of death, and sheltering behaviors before death. RESULTS: Of the 247 fatalities, females and older adults were at highest risk for tornado-related deaths. Most deaths were directly related to the tornadoes, on scene, and trauma-related. The majority of the deceased were indoors in single-family homes. Word of mouth was the most common warning mechanism. CONCLUSIONS: This tornado event was the third deadliest in recent US history. Our findings support the need for local community shelters, enhanced messaging to inform the public of shelter locations, and encouragement of word-of-mouth warnings and personal and family preparedness planning, with a special focus on assisting vulnerable individuals in taking shelter.