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

NCT ID: NCT05323240

Last Updated: 2023-11-28

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

RECRUITING

Clinical Phase

NA

Total Enrollment

20 participants

Study Classification

INTERVENTIONAL

Study Start Date

2022-05-12

Study Completion Date

2025-12-20

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

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.

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Air Pollution

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Allocation Method

RANDOMIZED

Intervention Model

CROSSOVER

Primary Study Purpose

BASIC_SCIENCE

Blinding Strategy

DOUBLE

Participants Investigators

Study Groups

Review each arm or cohort in the study, along with the interventions and objectives associated with them.

Filtered air exposure

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.

Group Type EXPERIMENTAL

Filtered air exposure

Intervention Type OTHER

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

PM exposure

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.

Group Type EXPERIMENTAL

PM exposure

Intervention Type 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.

Interventions

Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.

PM exposure

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.

Intervention Type OTHER

Filtered air exposure

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

Intervention Type OTHER

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

1. . Age 18-35 years old healthy male and female (BMI values between 19 and 30).
2. . 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 \[described by Tanaka et al.: (2001) J. Am. Coll. Cardiol: 208bpm-((0.7) x (age in years))\]
3. . Normal baseline 12-lead EKG.
4. . 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.
5. . Oxygen saturation greater than 94% at the time of physical exam.

Exclusion Criteria

1. . Individuals with a diagnosis of COVID-19 and/or hospitalized for COVID-19.
2. . Individuals not vaccinated for COVID-19, or, not 14 days beyond the final dose of receiving a COVID-19 vaccine.
3. . Individuals with a history of acute or chronic cardiovascular disease, chronic respiratory disease, diabetes, rheumatologic diseases, or immunodeficiency state.
4. . 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.
5. . Individuals with asthma and a history of asthma.
6. . Individuals who are allergic to chemical vapors or gases.
7. . Females who are pregnant, attempting to become pregnant, or breastfeeding.
8. . Individuals who are currently smoking (including vaping, hookah, e-cigarette) or have a smoking history within 1 year of study.
9. . Individuals living with a smoker who smokes inside the house.
10. . 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.
11. . Individuals with occupational exposures to high levels of vapors, dust, gases, or fumes on an on-going basis.
12. . Individuals with uncontrolled hypertension (\>140 systolic or \>90 diastolic).
13. . Individuals who do not understand or speak English.
14. . Individuals who are unable to perform the exercise required for the study.
15. . Individuals with a history of skin allergies to adhesives used in securing EKG electrodes.
16. . Individuals with unspecified diseases, conditions, or medications that might influence the responses to the exposures, as judged by the medical staff.
17. . Individuals who are unwilling or unable to stop taking over-the-counter pain medications such as aspirin, ibuprofen (Advil, Motrin), naproxen (Aleve), or other non-steroidal anti-inflammatory ("NSAID") medications for 48 hours prior to the exposures and post-exposure visits. Individuals taking vitamins or supplements that the investigators believe may impact the results of the study who are unwilling or unable to stop taking them for at least two weeks before the study. Those not specifically mentioned here may be reviewed by the investigators prior to an individual's inclusion in the study.
18. . Individuals taking systemic steroids or beta-blocker medications.
19. . Individuals with a hemoglobin A1c (HbA1c) level \> 6.4%.
20. . Individuals who are claustrophobic.
Minimum Eligible Age

18 Years

Maximum Eligible Age

35 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

Yes

Sponsors

Meet the organizations funding or collaborating on the study and learn about their roles.

U.S. EPA Human Studies Facility

FED

Sponsor Role lead

Responsible Party

Identify the individual or organization who holds primary responsibility for the study information submitted to regulators.

Haiyan Tong

Principal Investigator

Responsibility Role PRINCIPAL_INVESTIGATOR

Locations

Explore where the study is taking place and check the recruitment status at each participating site.

EPA Human Studies Facility

Chapel Hill, North Carolina, United States

Site Status RECRUITING

Countries

Review the countries where the study has at least one active or historical site.

United States

Central Contacts

Reach out to these primary contacts for questions about participation or study logistics.

Patrice Ratliffe

Role: CONTACT

919-966-0607

Facility Contacts

Find local site contact details for specific facilities participating in the trial.

Patrice Ratliffe

Role: primary

919-966-0607

Other Identifiers

Review additional registry numbers or institutional identifiers associated with this trial.

RPTCAP

Identifier Type: -

Identifier Source: org_study_id