NCT04029129

Reducing Traffic Pollution Exposure Improves Blood Pressure

Near Highway Pollution: From Research to Action

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 77 (actual)
• Sponsor: UConn Health · Academic / Other
• Sex: All
• Age: 40 Years – 75 Years
• Healthy volunteers: Accepted

Summary

This randomized trial assessed the effect of modifying building envelop and level of air filtration on blood pressure over two hour exposure sessions.

Detailed description

Living close to major roadways is associated with elevated blood pressure (BP) amongst other adverse health effects. There is growing evidence that ultrafine particles (UFP, \<100 nm in diameter), which are elevated near major roads and highways, contribute to such risks. We assessed the efficacy of high efficiency particulate arrestance (HEPA) filtration and building envelope adjustment at reducing exposure to and health effects of air pollution next to major highways. We used a randomized three-period crossover trial design to assign 77 participants (aged 40-75 and without diagnosis of hypertension) to three two-hour exposure sessions. Sessions were conducted in one of two rooms immediately adjacent to highways. High, medium and low exposures were attained by varying the degree of air exchange and amount of HEPA filtration in the room. During high exposure sessions, the room was ventilated with outdoor air and no filtration was used. During low exposure sessions, leakage of outdoor air into the room was minimized and HEPA filtration was maximized. During medium exposure sessions, a moderate amount of HEPA filtration was used (less than half of that used in low sessions). Indoor particle number and black carbon (BC) concentrations (i.e., markers of traffic-related air pollution) were monitored continuously. During each session participants sat quietly and wore noise-cancelling headphones, while their BP was monitored every ten minutes using an ambulatory BP monitor. We monitored pulse and oxygen saturation continuously.

Conditions

• Air Pollution

Interventions

Type	Name	Description
OTHER	Air filtration and building envelop modifications	Air filters and closing and sealing of windows and doors was used to reduce infiltration of air pollution from outdoors in rooms next to major highways at rush hour.

Timeline

• Start date: 2018-03-01
• Primary completion: 2018-06-15
• Completion: 2018-06-15
• First posted: 2019-07-23
• Last updated: 2023-09-28
• Results posted: 2023-09-28

Locations

1 site across 1 country: United States