B56-08 Variations in Levels of Black Carbon Particulate Matter by Walkways and Time of Day in New York City

Rationale Black carbon (BC), also known as elemental carbon, is a byproduct of incomplete combustion and a major component of PM2.5. Black carbon exposure has been linked to adverse health outcomes, including asthma, cognitive deficit, and elevated blood pressure. The present study focused on BC exposures in Brooklyn, NY, a marginalized community with historically high asthma rates. The aim of this study was to assess the relationship between childhood black carbon exposure and community open space, while accounting for traffic volume. Methods Black carbon was collected along five community-selected routes using a microAeth AE51 aethalometer in the vicinity of school traffic. Samples were collected during the morning and afternoon for two weekdays and one weekend day for four separate weeks. Vehicle traffic was monitored using the Counter+ app. Route and time tracking were recorded with the MyTracks app. Maps showing black carbon exposure levels along routes were generated through ArcGis Pro and statistical analysis was conducted with GraphPad Prism. Results Statistical analyses indicated significant changes in exposure levels, depending on time of day and route. Routes with elevated BC levels were associated with higher traffic counts. Traffic intersections were associated with higher black carbon levels than walkways (p < 0.001). There was no significant association between community open space and black carbon levels. Conclusions Exposure levels varied among routes and by time of day, and were highest at intersections. These preliminary data warrant further studies on potential health outcomes due to the levels of exposure in the area. This abstract is funded by: None