We are hard at work on finalizing six new datasets: check out our latest newsletter for more details.
CANUE member Dr. Michael Jerrett presents at the National Academies of Sciences Engineering and Medicine – Geographical Sciences Committee Meeting, May 2018. Hear Dr. Jerrett’s thoughts on how we deal with individual movements through time and space, what that means for environmental exposures, and how we capture data to characterize exposures for health studies.
Kernel Density Estimation as a Measure of Environmental Exposure Related to Insulin Resistance in Breast Cancer Survivors
Marta M. Jankowska, Loki Natarajan, Suneeta Godbole, Kristin Meseck, Dorothy D. Sears, Ruth E. Patterson and Jacqueline Kerr
Cancer Epidemiol Biomarkers Prev; 26(7); 1078–84. Published July 2017
Environmental factors may influence breast cancer; however, most studies have measured environmental exposure in neighborhoods around home residences (static exposure). We hypothesize that tracking environmental exposures over time and space (dynamic exposure) is key to assessing total exposure. This study compares breast cancer survivors’ exposure to walkable and recreation-promoting environments using dynamic Global Positioning System (GPS) and static home-based measures of exposure in relation to insulin resistance.
GPS data from 249 breast cancer survivors living in San Diego County were collected for one week along with fasting blood draw. Exposure to recreation spaces and walkability was measured for each woman’s home address within an 800 m buffer (static), and using a kernel density weight of GPS tracks (dynamic). Participants’ exposure estimates were related to insulin resistance (using the homeostatic model assessment of insulin resistance, HOMA-IR) controlled by age and body mass index (BMI) in linear regression models.
The dynamic measurement method resulted in greater variability in built environment exposure values than did the static method. Regression results showed no association between HOMA-IR and home-based, static measures of walkability and recreation area exposure. GPS-based dynamic measures of both walkability and recreation area were significantly associated with lower HOMA-IR (P < 0.05).
Dynamic exposure measurements may provide important evidence for community- and individual-level interventions that can address cancer risk inequities arising from environments wherein breast cancer survivors live and engage.
Impact: This is the first study to compare associations of dynamic versus static built environment exposure measures with insulin outcomes in breast cancer survivors.
Environmental noise pollution and risk of preeclampsia.
Auger N, Duplaix M, Bilodeau-Bertrand M, Lo E, Smargiassi A.
Environmental noise exposure is associated with a greater risk of hypertension, but the link with preeclampsia, a hypertensive disorder of pregnancy, is unclear.
We sought to determine the relationship between environmental noise pollution and risk of preeclampsia during pregnancy.
We analyzed a population-based cohort comprising 269,263 deliveries on the island of Montreal, Canada between 2000 and 2013. We obtained total environmental noise pollution measurements (LAeq24, Lden, Lnight) from land use regression models, and assigned noise levels to each woman based on the residential postal code. We computed odds ratios (OR) and 95% confidence intervals (CI) for the association of noise with preeclampsia in mixed logistic regression models with participants as a random effect, and adjusted for air pollution, neighbourhood walkability, maternal age, parity, multiple pregnancy, comorbidity, socioeconomic deprivation, and year of delivery. We assessed whether noise exposure was more strongly associated with severe or early onset preeclampsia than mild or late onset preeclampsia.
Prevalence of preeclampsia was higher for women exposed to elevated environmental noise pollution levels (LAeq24h ≥ 65 dB(A) = 37.9 per 1000 vs. <50 dB(A) = 27.9 per 1000). Compared with 50 dB(A), an LAeq24h of 65.0 dB(A) was not significantly associated the risk of preeclampsia (OR 1.09, 95% CI 0.99-1.20). Associations were however present with severe (OR 1.29, 95% CI 1.09-1.54) and early onset (OR 1.71, 95% CI 1.20-2.43) preeclampsia, with results consistent across all noise indicators. The associations were much weaker or absent for mild and late preeclampsia.
Environmental noise pollution may be a novel risk factor for pregnancy-related hypertension, particularly more severe variants of preeclampsia.
For his presentation, Dr. Baldauf will summarize the U.S. EPA’s research program on the use of built and green infrastructure to mitigate local air pollution impacts from transportation facilities. His presentation will describe the current scientific understanding of how urban infrastructure affects local air quality, including a review of projects conducted in the US and other parts of the world investigating solid noise barrier and roadside vegetation impacts in particular. He will also summarize existing resources developed by the U.S. EPA to assist environmental and health professionals, urban planners, and developers to identify best practices to mitigate local air pollution impacts and avoid unintended consequences where urban infrastructure may exacerbate local air quality concerns.
Dr. Baldauf has over 20 years of experience conducting research on emissions, air quality impacts, and adverse health effects from exposures to air pollution emitted by transportation and industrial sources. His research focuses on the development of policies and practices to mitigate air pollution emissions and impacts at local, urban, and global scales. His research has led to national emissions standards and best practices to mitigate air pollution impacts using urban development including built and green infrastructure. He has a joint affiliation with the U.S. Environmental Protection Agency’s Office of Research & Development and the Office of Transportation & Air Quality where he has led cross-disciplinary research teams focusing on air quality measurements, air dispersion modeling, and sustainable transportation and urban development issues. He also maintains Adjunct Professor appointments in the School of Engineering at North Carolina State University and Texas A&M University. Dr. Baldauf co-manages the U.S. EPA’s Mobile Source Emissions Research Laboratory and led the cross-agency Sustainable Transportation Initiative. He has published over 100 peer-review journal articles and several book chapters on these topics during his career at the U.S. EPA.