Health Effects of Repeated Exposure to Low Levels of Concentrated Ambient Particles in Healthy Young Volunteers

NCT05323240 | Unknown

• 1 other identifier: RPTCAP
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

Purpose: To determine whether 3-day consecutive exposures to levels of fine particulate matter (PM2.5) that are close to the current 24-hr national standard will cause changes in inflammatory and cardiopulmonary endpoints in healthy young individuals. Participants: 20 healthy males and females aged 18-35 years. Procedures (methods): Subjects will be randomly exposed to three consecutive days of filtered air (4 hr/day) and three consecutive days of PM2.5 (approximately 35 µg/m3; 4 hr/day) in an exposure chamber. Blood collection for inflammatory factors such as C-reactive protein (CRP), clotting factors; heart rate variability (HRV); spirometry; and a symptom questionnaire will be conducted before and after each exposure.

Conditions

Air Pollution

Outcome Measures

Primary Outcomes (4)

• Blood inflammation marker, CRP, will be measured 2 hours before each air exposure day and follow up day in 20 subjects

  Venous blood will be collected for CRP measurement 2 hours before each air exposure day on day 1, day 2, day 3, and follow up day in 20 subjects.

  Four days

• Blood inflammation marker, CRP, will be measured 2 hours before each PM exposure day and follow up day in 20 subjects

  Venous blood will be collected for CRP measurement 2 hours before each PM exposure day on day 1, day 2, day 3 and follow up day in 20 subjects.

  Four days

• Blood inflammation marker, CRP, will be measured 1 hour after each air exposure day in 20 subjects

  Venous blood will be collected for CRP measurement 1 hour after each air exposure day on day 1, day 2, and day 3 in 20 subjects.

  Three days

• Blood inflammation marker, CRP, will be measured 1 hour after each PM exposure day in 20 subjects

  Venous blood will be collected for CRP measurement 1 hour after each PM exposure day on day 1, day 2, and day 3 in 20 subjects.

  Three days

Secondary Outcomes (8)

• Spirometry will be measured 1 hour before each air exposure day and follow up day in 20 subjects

  Four days

• Spirometry will be measured 1 hour before each PM exposure day and follow up day in 20 subjects

  Four days

• Ambulatory ECG will be measured 2 hours before each air exposure day and follow up day in 20 subjects

  Four days

• Ambulatory ECG will be measured 2 hours before each PM exposure day and follow up day in 20 subjects

  Four days

• Spirometry will be measured 1 hour after each air exposure day in 20 subjects

  Three days

Study Arms (2)

Filtered air exposure

EXPERIMENTAL

Subjects will be randomly exposed to three consecutive days of filtered air exposure arm in a double-blind cross-over fashion in an exposure chamber, and exposures will be separated by a minimum of 13 days from the PM2.5 arm.

Other: Filtered air exposure

PM exposure

EXPERIMENTAL

Subjects will be randomly exposed to three consecutive days of PM2.5 exposure arm in a double-blind cross-over fashion in an exposure chamber, and exposures will be separated by a minimum of 13 days from the filtered air arm.

Other: PM exposure

Interventions

PM exposure OTHER

To determine whether 3-day consecutive exposures to levels of fine particulate matter (PM2.5) that are close to the current 24-hr national standard will cause changes in inflammatory and cardiopulmonary endpoints.

PM exposure

Filtered air exposure OTHER

To determine whether 3-day consecutive exposures to filtered air will cause changes in inflammatory and cardiopulmonary endpoints.

Filtered air exposure

Eligibility Criteria

• Age: 18 Years - 35 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Age 18-35 years old healthy male and female (BMI values between 19 and 30).
• Physical conditioning allowing intermittent, moderate exercise for 2 hours, and ability to complete the exposure exercise regimen to induce a minute ventilation rate of 20 L/min/m2 for 15 min without exceeding 80% of projected maximal heart rate. Predicted maximal heart rate will be calculated using the equation \[described by Tanaka et al.: (2001) J. Am. Coll. Cardiol: 208bpm-((0.7) x (age in years))\]
• Normal baseline 12-lead EKG.
• Normal lung function based on NHANES III reference values. i. Forced vital capacity (FVC) ≥ 80% of that predicted for age, gender, ethnicity, and height.
• ii. Forced expiratory volume in one second (FEV1) ≥ 80% of that predicted for age, gender, ethnicity, and height.
• iii: FEV1/FVC ratio ≥ 80% of predicted values.
• Oxygen saturation greater than 94% at the time of physical exam.

You may not qualify if:

• Individuals with a diagnosis of COVID-19 and/or hospitalized for COVID-19.
• Individuals not vaccinated for COVID-19, or, not 14 days beyond the final dose of receiving a COVID-19 vaccine.
• Individuals with a history of acute or chronic cardiovascular disease, chronic respiratory disease, diabetes, rheumatologic diseases, or immunodeficiency state.
• Individuals with a CVD risk score greater than 10% using the ACC/AHA ASCVD risk calculator (based on the 10-year risk of heart disease or stroke using the Atherosclerotic Cardiovascular Disease algorithm published in 2013 American College of Cardiology/American Heart Association Guideline on the Assessment of Cardiovascular risk.
• Individuals with asthma and a history of asthma.
• Individuals who are allergic to chemical vapors or gases.
• Females who are pregnant, attempting to become pregnant, or breastfeeding.
• Individuals who are currently smoking (including vaping, hookah, e-cigarette) or have a smoking history within 1 year of study.
• Individuals living with a smoker who smokes inside the house.
• Individuals with a body mass index (BMI) \>30 or \<19. Body mass index is calculated by dividing the weight in kilograms by the square of the height in meters.
• Individuals with occupational exposures to high levels of vapors, dust, gases, or fumes on an on-going basis.
• Individuals with uncontrolled hypertension (\>140 systolic or \>90 diastolic).
• Individuals who do not understand or speak English.
• Individuals who are unable to perform the exercise required for the study.
• Individuals with a history of skin allergies to adhesives used in securing EKG electrodes.

Sponsors & Collaborators

• U.S. EPA Human Studies Facility: lead

Study Sites (1)

EPA Human Studies Facility

Chapel Hill, North Carolina, 27514, United States

RECRUITING

Central Study Contacts

Patrice Ratliffe

CONTACT

919-966-0607; Ratliffe.Patrice@epa.gov

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: FED
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: November 29, 2021
• First Posted: April 12, 2022
• Study Start: May 12, 2022
• Primary Completion: June 20, 2024
• Study Completion: December 20, 2025
• Last Updated: November 28, 2023

Record last verified: 2023-11

Locations

US (1)