The NYC Congestion Pricing Program significantly reduced morning rush hour PM1.0 (-0.33ug/m3, p=0.02) and PM2.5 (-0.47ug/m3, p=0.04), but did not significantly change asthma ED visits.
Observational
Does the New York City Congestion Pricing Program reduce fine particulate matter air pollution and asthma-related ED visits?
The NYC Congestion Pricing Program reduced peak morning rush hour fine particulate matter but did not significantly reduce asthma ED visits within the first 6 months.
Effect estimate: DDD -0.33ug/m3 (PM1.0) and -0.47ug/m3 (PM2.5)
p-value: p=0.02 for PM1.0, 0.04 for PM2.5
Abstract A Congestion Pricing Program went into effect in New York City (NYC) on January 5, 2025, charging a toll for vehicles entering the area of Manhattan south of 60th Street between 5am and 9pm on weekdays and from 9am to 9pm on weekends. This study aims to assess the impact of this policy on fine particulate matter (PM1.0 and PM2.5) air pollution and asthma-related emergency department (ED) visits. Hourly PM1 and PM2.5 data from January 1st, 2024 to June 30, 2025 were downloaded from 30 PurpleAir monitors in NYC, 11 located inside the Congestion Pricing Zone, 19 outside. A Difference-in-Difference-in-Differences (DDD) model adjusted for weekends and month of year is used to assess the reductions of PM1 and PM2.5 in the congestion pricing area after policy implementation during morning rush hours. Daily asthma and COPD ED visits were downloaded from the NYC Department of Health and Mental Hygiene syndromic surveillance database for January 2024 to June 2025. A controlled-interrupted time series model adjusting for seasonality was applied to assess the immediate and longer-term changes in ED visits inside the congestion pricing zone compared with outside. Compared with areas outside of the congestion pricing zone before policy started, significant further reductions in PM1.0 (-0.33ug/m3, DDD interaction term p-value=0.02) and PM2.5 (-0.47ug/m3, DDD interaction term p-value=0.04) were only observed for morning rush hours (8-11am) in the congestion pricing area after policy implementation. Such reductions are significant only on weekdays (PM1.0 DDD estimate -0.38ug/m3, p-value=0.03), not on weekends (p-value = 0.36). Interrupted time series analysis did not detect significant changes in asthma ED visits inside or outside of the congestion pricing area, nor were there significant differences between ED visit rate trends in the two zones concurrent with policy implementation. Our preliminary analysis found congestion pricing in NYC is associated with a reduction in peak weekday morning rush hour PM1.0 and PM2.5 levels, but also compensating increases in off-peak hours. This displacement across the day is consistent with the fact that we were unable to detect a significant overall daily respiratory health benefit within the first 6 months of implementation. Potential longer term respiratory health benefits, as well as possible confounding by wildfire pollution, need further investigation. This abstract is funded by: None
Yu et al. (Fri,) conducted a observational in Air pollution and asthma-related emergency department visits. Congestion Pricing Program vs. Areas outside the congestion pricing zone and pre-policy period was evaluated on Changes in PM1.0 and PM2.5 during morning rush hours and asthma ED visits (DDD -0.33ug/m3 (PM1.0) and -0.47ug/m3 (PM2.5), p=0.02 for PM1.0, 0.04 for PM2.5). The NYC Congestion Pricing Program significantly reduced morning rush hour PM1.0 (-0.33ug/m3, p=0.02) and PM2.5 (-0.47ug/m3, p=0.04), but did not significantly change asthma ED visits.
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