Impact of Spatiotemporal Factors on Exposure to PM2.5 as Residents move between Residential, Commercial and Recreational areas
Abstract
Reduction of annual average PM2.5 concentrations by 2.5 µg/m3 is associated with a 3.5% reduction in all-cause mortality. However, population exposure is typically assessed assuming that a person spends their full day at their residential address. Numerous studies have demonstrated that PM2.5 can have small-scale spatial variations. Consequentially, the impact of spatial movement in a person's day is often not represented in epidemiology studies. To address this issue and to improve our understanding of the exposure of residents, a network of 50 low-cost sensors were deployed in Allegheny county (Pennsylvania, USA) and used for prediction modeling of PM2.5 using spatial and temporal variables. The county was gridded and categorized into 4 land cover areas (residential, commercial, recreational and other) at 100m resolution. Daily concentrations were predicted at each grid location for 2017 using land use random forest model (LURF). The predicted concentrations were also divided into `weekday' and `weekend' concentrations to account for variations in movement pattern. Using a Monte Carlo simulation with 100,000 iterations, annual average PM2.5 was computed for various combinations of time spent in different land cover areas. Different behavior patterns were assigned for weekdays and weekends. Also, to account for density variabilities in residential areas, weight-based probability was assigned to each residential area, with medium and high density areas two to three times as probable as low density areas, respectively. Weekday and weekend combinations were then proportionately summed to compare estimated exposure of the residents using static (residential) vs movement-based models. Findings of this study can be used to get a more accurate representation of exposure. Additionally, combined with epidemiology studies on impact of PM2.5 concentrations, it can help us determine the reduction in exposure and mortality rate due to behavioral changes.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2020
- Bibcode:
- 2020AGUFMA220.0012J
- Keywords:
-
- 0345 Pollution: urban and regional;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0394 Instruments and techniques;
- ATMOSPHERIC COMPOSITION AND STRUCTURE