Ambient Environmental Exposures while Cycling in Austin, TX (September 2021)

Data were collected for a study conducted in the City of Austin, Texas, USA. Twice daily (7:30–8:30, 17:30–18:30) on one weekday and weekend day per route in September 2021, researchers rode bicycles with five sensors measuring fine particulate matter (PM_2.5), total volatile organic compounds (VOCs), sounds, air temperature, relative humidity, light intensity, and geographic location. They used a neural network to separate audio files into anthropogenic and natural sounds. From linear mixed effects models that adjusted for afternoons and weekdays, they found that the trail was associated with higher levels of PM_2.5 (<i>b</i> = 0.31; 95% CI = 0.18, 0.44; p = 0.01), total VOCs (<i>b</i> = 0.11; 95% CI = 0.06, 0.17; p = 0.01), natural sounds (<i>b</i> = 0.18; 95% CI = 0.08, 0.50; p = 0.001), and relative humidity (<i>b</i> = 3.61; 95% CI = 0.56, 6.66; p = 0.02) and lower levels of anthropogenic sounds (<i>b</i> = -0.83; 95% CI = -1.28, -0.38; p = 0.001), temperature (<i>b</i> = -0.68; 95% CI = -1.15, -0.22; p = 0.02), and light intensity (<i>b</i> = -0.36; 95% CI = -0.47, -0.24; p = 0.01) compared to the road.