Air PollutionNCT05323240
Health Effects of Repeated Exposure to Low Levels of Concentrated Ambient Particles in Healthy Young Volunteers
A study testing PM exposure and Filtered air exposure in people with Air Pollution, run by U.S. EPA Human Studies Facility at 1 site in United States.
Trial 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. Read more about this study
- Who is it for?
- Ages 18 to 35 yearsHealthy volunteers can take part
- Conditions the study is for
- Air Pollution
- What is being tested?
- PM exposure and Filtered air exposure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 20 participants
- Where
- 1 siteUnited States
- Study dates
- 12 May 2022to 20 Dec 2025
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 35 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- . 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.
- 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.
Who cannot join
- . 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.
Show all 20Show fewer
- . 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.
- . Individuals with unspecified diseases, conditions, or medications that might influence the responses to the exposures, as judged by the medical staff.
- . 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.
- . Individuals taking systemic steroids or beta-blocker medications.
- . Individuals with a hemoglobin A1c (HbA1c) level > 6.4%.
- . Individuals who are claustrophobic.
Trial locations and contacts
1 site in 1 country.
United States1 site, 1 recruiting
- Recruiting
EPA Human Studies Facility
Chapel Hill, North Carolina, 27514
Patrice Ratliffe, 919-966-0607, Ratliffe.patrice@epa.gov
Haiyan Tong, MD, PhD
About this study
Official title: Repeated Exposure Study
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
- Being tested
- PM exposure, Filtered air exposure
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
PM exposureOther
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.
Filtered air exposureOther
To determine whether 3-day consecutive exposures to filtered air will cause changes in inflammatory and cardiopulmonary endpoints.
| Study group | Role | What they receive |
|---|---|---|
| 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. Receives: 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. Receives: Other: PM exposure |
What is being measured
The primary outcome is the main question the study is designed to answer.
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.
Measured: 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.
Measured: 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.
Measured: 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.
Measured: Three days
Secondary outcomes (8)
Spirometry will be measured 1 hour before each air exposure day and follow up day in 20 subjects
FEV1 and FVC will be measured by spirometry 1 hour before each air exposure day on day 1, day 2, day 3, and follow up day in 20 subjects.
Measured: Four days
Spirometry will be measured 1 hour before each PM exposure day and follow up day in 20 subjects
FEV1 and FVC will be measured by spirometry 1 hour before each PM exposure day on day 1, day 2, day 3 and follow up day in 20 subjects.
Measured: Four days
Ambulatory ECG will be measured 2 hours before each air exposure day and follow up day in 20 subjects
ECG QT interval and frequency power of ECG will be measured by Holter monitor for 5 minutes at 2 hour before each air exposure day on day 1, day 2, day 3, and follow up day in 20 subjects.
Measured: Four days
Ambulatory ECG will be measured 2 hours before each PM exposure day and follow up day in 20 subjects
ECG QT interval and frequency power of ECG will be measured by Holter monitor for 5 minutes at 2 hours before each PM exposure day on day 1, day 2, day 3, and follow up day in 20 subjects.
Measured: Four days
Spirometry will be measured 1 hour after each air exposure day in 20 subjects
FEV1 and FVC will be measured by spirometry 1 hour after each air exposure day on day 1, day 2, and day 3 in 20 subjects.
Measured: Three days
Spirometry will be measured 1 hour after each PM exposure day in 20 subjects
FEV1 and FVC will be measured by spirometry 1 hour after each PM exposure day on day 1, day 2, and day 3 in 20 subjects.
Measured: Three days
Ambulatory ECG will be measured 2 hours after each air exposure day in 20 subjects
ECG QT interval and frequency power of ECG will be measured by Holter monitor for 5 minutes at 2 hours after each air exposure day on day 1, day 2, and day 3 in 20 subjects.
Measured: Three days
Ambulatory ECG will be measured 2 hours after each PM exposure day in 20 subjects
ECG QT interval and frequency power of ECG will be measured by Holter monitor for 5 minutes at 2 hours after each PM exposure day on day 1, day 2, and day 3 in 20 subjects.
Measured: Three days
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted12 Apr 2022
- Study start12 May 2022
- Primary completion20 Jun 2024 (estimated)
- Study completion20 Dec 2025 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Air PollutionStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Double blind
- Who is masked
- Participant, Investigator
- Enrolment
- 20 participants (estimated)
Sponsor and investigators
- Lead sponsor
- U.S. EPA Human Studies Facility
- Sponsor type
- US federal agency
- Responsible party
- Principal investigator, Haiyan Tong, U.S. EPA Human Studies Facility
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05323240
- Sponsor's protocol ID
- RPTCAP
- Status last verified
- Nov 2023
- First submitted
- 29 Nov 2021
- Last updated
- 28 Nov 2023
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 28 Nov 2023. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Repeated Exposure Study
- ClinicalTrials.gov ID
- NCT05323240
- Acronym / sponsor ID
- RPTCAP
- Conditions
- Air Pollution
- Study type
- Interventional
- Recruitment status
- Unknown status
- Enrolment
- 20 participants (estimated)
- Lead sponsor
- U.S. EPA Human Studies FacilityUS federal agency
- Study start
- 12 May 2022 (actual)
- Primary completion
- 20 Jun 2024 (estimated)
- Study completion
- 20 Dec 2025 (estimated)
- First posted
- 12 Apr 2022 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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.
Study design
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Double blind (participant, investigator)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Filtered air exposure | Experimental | Other: Filtered air exposureSubjects 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. |
| PM exposure | Experimental | Other: PM exposureSubjects 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. |
Who may qualify
- Ages
- 18 to 35 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (7 listed)
- . 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.
- iii: FEV1/FVC ratio ≥ 80% of predicted values.
Key exclusion criteria (20 listed)
- . 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.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| PM exposureTo 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. | Other | PM exposure |
| Filtered air exposureTo determine whether 3-day consecutive exposures to filtered air will cause changes in inflammatory and cardiopulmonary endpoints. | Other | Filtered air exposure |
Primary outcome
Blood inflammation marker, CRP, will be measured 2 hours before each air exposure day and follow up day in 20 subjects
Time frame: Four days
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.
Blood inflammation marker, CRP, will be measured 2 hours before each PM exposure day and follow up day in 20 subjects
Time frame: Four days
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.
Blood inflammation marker, CRP, will be measured 1 hour after each air exposure day in 20 subjects
Time frame: Three days
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.
Blood inflammation marker, CRP, will be measured 1 hour after each PM exposure day in 20 subjects
Time frame: Three days
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.
8 secondary outcomes
Spirometry will be measured 1 hour before each air exposure day and follow up day in 20 subjects
Time frame: Four days
Spirometry will be measured 1 hour before each PM exposure day and follow up day in 20 subjects
Time frame: Four days
Ambulatory ECG will be measured 2 hours before each air exposure day and follow up day in 20 subjects
Time frame: Four days
Ambulatory ECG will be measured 2 hours before each PM exposure day and follow up day in 20 subjects
Time frame: Four days
Spirometry will be measured 1 hour after each air exposure day in 20 subjects
Time frame: Three days
Spirometry will be measured 1 hour after each PM exposure day in 20 subjects
Time frame: Three days
Ambulatory ECG will be measured 2 hours after each air exposure day in 20 subjects
Time frame: Three days
Ambulatory ECG will be measured 2 hours after each PM exposure day in 20 subjects
Time frame: Three days
Results and safety
Results are not available in the source record.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 28 Nov 2023.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing PM exposure and Filtered air exposure in people with Air Pollution, run by U.S. EPA Human Studies Facility at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 7 inclusion and 20 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: status not confirmed, as of the sponsor's last update on 28 Nov 2023. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
Results are not available in the source record.
How can a doctor refer a patient or contact the research team?
Contact Patrice Ratliffe (919-966-0607, Ratliffe.Patrice@epa.gov), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Blood inflammation marker, CRP, will be measured 2 hours before each air exposure day and follow up day in 20 subjects (time frame: Four days). The study lists 4 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 28 Nov 2023.