Wood Smoke Exposure for Healthy Subjects

(MASKOFF Trial)

Overseen By Patrice Ratliffe

Age: 18 - 65

Sex: Any

Trial Phase: Academic

Sponsor: University of North Carolina, Chapel Hill

Must not be taking: Systemic steroids, Oral anticoagulants, ß-blockers, Antihistamines

Disqualifiers: Cardiovascular disease, Diabetes, Asthma, Cancer, others

Compensation: Varies

Number of Visits: 6

80 Participants Needed

Trial Summary

Will I have to stop taking my current medications?

The trial requires that you stop taking certain medications, such as systemic steroids, oral anticoagulants, ß-blockers, prebiotics, probiotics, and antihistamines. Other medications will be reviewed on a case-by-case basis by the medical staff.

Is wood smoke exposure safe for humans?

Research indicates that exposure to wood smoke can be harmful to human health, as it is associated with various adverse effects, including respiratory infections and immune system impacts. It contains pollutants that are known to be harmful, and more studies are needed to fully understand the risks. ^{1 2 3 4 5}

How does the treatment 'Exposure to Wood Smoke' differ from other treatments for this condition?

The 'Exposure to Wood Smoke' treatment is unique because it involves intentionally exposing healthy subjects to wood smoke, which is not a standard treatment for any condition. This approach is novel as it aims to study the effects of wood smoke exposure, unlike other treatments that typically focus on reducing or eliminating exposure to harmful smoke. ^{6 7 8 9 10}

What is the purpose of this trial?

MASKOFF Clinical Trials 8/22/23 Brief Summary: Purpose: The study is designed to investigate cardiovascular effects of young healthy human subjects exposed to wood smoke. Participants: Approximately 80 young (18-35 years old) healthy subjects to complete. Procedure (methods): After consenting to participate in the study, subjects will be exposed first to filtered air and on the next exposure day to approximately 500 µg/m\^3 wood smoke. Both exposures will be 2 hours long with alternating 15 min of exercise (cycle ergometer) and 15 min rest period. The exercise level will be adjusted to achieve approximately 20 L/min/m\^2 minute ventilation. Venous blood samples and measurements of lung, cardiac and vascular function will be made prior to and immediately following each exposure. Induced sputum samples and nasal epithelial lining fluid will be collected approximately 24 hours post each exposure.

Research Team

James Samet, PhD

Principal Investigator

Environmental Protection Agency (EPA)

Eligibility Criteria

This trial is for healthy adults aged 18-35 with a BMI of 19-30, normal lung and heart function, up-to-date COVID vaccinations, and the ability to do mild exercise. It's not for those on long-term steroids or blood thinners, with high blood pressure or diabetes, cardiovascular risks over 10%, recent surgeries, certain medication use, pregnancy/breastfeeding status, smokers (including recent history), non-English speakers who can't consent properly.

Inclusion Criteria

My lung function is at least 80% of the expected level for someone my age, gender, ethnicity, and height.

Oxygen saturation greater than 94% at the time of physical exam

My lung function, measured by FEV1, is within the normal range for my age, gender, ethnicity, and height.

Exclusion Criteria

Individuals with a cardiovascular disease risk score greater than 10% using the ACC/AHA ASCVD risk calculator

I have had a respiratory illness in the last 6 weeks.

I am currently on long-term steroids or blood thinners.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

1 visit (in-person)

Consenting

Participants undergo consenting process, medical review, and initial tests including spirometry and blood sampling

1 day

1 visit (in-person)

Exposure

Participants are exposed to filtered air and wood smoke on separate days with exercise and rest periods, followed by various tests

2 days

2 visits (in-person)

Follow-up

Participants are monitored for safety and effectiveness after exposure, including tests and sample collection

2 days

2 visits (in-person)

Treatment Details

Interventions

• Exposure to Wood Smoke

Trial Overview The MASKOFF study examines how wood smoke affects the heart and lungs in healthy young adults. Participants will breathe filtered air then wood smoke during two separate sessions involving rest and exercise intervals while their blood samples are taken along with lung and heart measurements before and after exposure.

Participant Groups

Group I: Wood Smoke Experimental Treatment 1 Intervention

Subjects will be exposed to air containing wood smoke for 2 hours with alternating 15 minutes of exercise (cycle ergometer) and rest.

Group II: Filtered air Placebo Group 1 Intervention

Subjects will be exposed once to filtered air for 2 hours with alternating 15 minutes of exercise (cycle ergometer) and rest.

Who Is Running the Clinical Trial?

University of North Carolina, Chapel Hill

Lead Sponsor

Trials

1,588

Recruited

4,364,000+

Environmental Protection Agency (EPA)

Collaborator

Trials

40

Recruited

95,500+

Findings from Research

In Sub-Saharan Africa, personal exposure levels to wood smoke pollutants, such as PM2.5 and carbon monoxide, significantly exceed World Health Organization guidelines, with females experiencing higher exposure than males.

Strong associations were found between wood smoke exposure and various health issues, including respiratory diseases, increased blood pressure, low birth weight, and even under-five mortality, highlighting the urgent need for interventions to reduce this exposure.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Exposure to Wood Smoke and Associated Health Effects in Sub-Saharan Africa: A Systematic Review. Bede-Ojimadu, O., Orisakwe, OE.[2021]

Increased use of woodburning for heating in North America has led to greater public exposure to harmful woodsmoke pollutants, raising concerns about health risks, especially for children.

The review highlights a significant gap in research on the toxicological effects of woodsmoke exposure, emphasizing the need for more studies to understand its impact on health and to inform regulatory standards.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The toxicology of inhaled woodsmoke. Zelikoff, JT., Chen, LC., Cohen, MD., et al.[2022]

Epidemiological studies have explored the health effects of biomass smoke in various settings, highlighting the need for diverse study designs to accurately assess these impacts.

The Health Effects Workgroup emphasized the importance of using biomarkers and robust study designs to evaluate health outcomes in communities exposed to wood smoke from sources like wildfires and residential burning.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Biomass smoke exposures: health outcomes measures and study design. Noonan, CW., Balmes, JR.[2010]

Woodsmoke contains harmful pollutants, including carcinogenic compounds like carbon monoxide (CO) and nitrogen oxides (NOx), which pose significant health risks similar to those from other combustion sources, as established by extensive research.

The review questions whether woodsmoke should be regulated separately due to its unique properties and health impacts, suggesting that further research is needed to fully understand its risks compared to other ambient particles.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Woodsmoke health effects: a review. Naeher, LP., Brauer, M., Lipsett, M., et al.[2022]

Acute exposure to wood smoke in healthy young adults showed minimal overall impact on nasal inflammatory responses to a live attenuated influenza virus, with only IP-10 protein levels being suppressed after exposure.

However, the study revealed significant sex-specific differences in inflammatory responses, indicating that males and females react differently to wood smoke exposure and subsequent viral inoculation, which suggests the need for further research on how pollutants affect health based on sex.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Wood Smoke Exposure Alters Human Inflammatory Responses to Viral Infection in a Sex-Specific Manner. A Randomized, Placebo-controlled Study. Rebuli, ME., Speen, AM., Martin, EM., et al.[2020]

About 37% of parents in rural Appalachian communities reported having at least one smoker in the household, but 50% of children aged 7-9 had detectable levels of cotinine in their serum, indicating significant secondhand smoke exposure.

The study found that 36.6% of children in Appalachian counties were exposed to secondhand smoke, which is much higher than the national average of 7.6%, highlighting the need for targeted interventions to reduce tobacco exposure in these communities.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Serum Cotinine versus Parent Reported Measures of Secondhand Smoke Exposure in Rural Appalachian Children. Yeramaneni, S., Yolton, K., Kannan, K., et al.[2022]

A study of 24,791 nonsmokers aged 12 and older found that exposure to secondhand smoke (SHS) at home resulted in significantly higher serum cotinine levels (0.522 ng/mL) compared to exposure at work (0.055 ng/mL), indicating that home environments pose a greater risk for SHS exposure.

The findings suggest a need for stronger public health initiatives to reduce SHS exposure at home, as it is associated with adverse health effects, particularly for nonsmokers.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Exposure to second hand smoke at home and work among nonsmokers. Jain, RB.[2022]

Accurate assessment of environmental tobacco smoke (ETS) exposure is crucial for health risk assessments, requiring unbiased estimates of the exposure-effect relationship and the distribution of ETS levels in various environments, such as workplaces and homes.

Key factors influencing ETS exposure assessments include the strength of the ETS source, environmental conditions, duration of exposure, and the timing of exposure relative to health outcomes, all of which must be considered to effectively estimate health risks.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Occupational exposure to environmental tobacco smoke and health risk assessment. Jaakkola, MS., Samet, JM.[2018]

In a 24-week study involving 150 adult smokers, switching to tobacco-heating cigarettes, snus, or ultra-low yield tobacco-burning cigarettes resulted in reduced exposure to harmful substances compared to traditional cigarette smoking.

The study highlights the differences in tobacco exposure among various products, contributing to the understanding of a risk continuum in tobacco use.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Switching from usual brand cigarettes to a tobacco-heating cigarette or snus: Part 2. Biomarkers of exposure. Ogden, MW., Marano, KM., Jones, BA., et al.[2019]

No level of exposure to secondhand smoke (SHS) is safe, as it can lead to serious health issues like heart disease and lung cancer in adults, and increased risks of sudden infant death syndrome and respiratory problems in children.

From 1988-1994 to 1999-2004, self-reported SHS exposure at home and serum cotinine levels in the U.S. population significantly declined by 51.2% and 44.7%, respectively, but the reduction was less pronounced in children aged 4-19, highlighting the need for ongoing efforts to protect this vulnerable group.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Disparities in secondhand smoke exposure--United States, 1988-1994 and 1999-2004. [2022]

References

1. United States pubmed.ncbi.nlm.nih.gov

Exposure to Wood Smoke and Associated Health Effects in Sub-Saharan Africa: A Systematic Review. [2021]

2. England pubmed.ncbi.nlm.nih.gov

The toxicology of inhaled woodsmoke. [2022]

3. England pubmed.ncbi.nlm.nih.gov

Biomass smoke exposures: health outcomes measures and study design. [2010]

4. England pubmed.ncbi.nlm.nih.gov

Woodsmoke health effects: a review. [2022]

5. United States pubmed.ncbi.nlm.nih.gov

Wood Smoke Exposure Alters Human Inflammatory Responses to Viral Infection in a Sex-Specific Manner. A Randomized, Placebo-controlled Study. [2020]

6. United States pubmed.ncbi.nlm.nih.gov

Serum Cotinine versus Parent Reported Measures of Secondhand Smoke Exposure in Rural Appalachian Children. [2022]

7. England pubmed.ncbi.nlm.nih.gov

Exposure to second hand smoke at home and work among nonsmokers. [2022]

8. United States pubmed.ncbi.nlm.nih.gov

Occupational exposure to environmental tobacco smoke and health risk assessment. [2018]

9. England pubmed.ncbi.nlm.nih.gov

Switching from usual brand cigarettes to a tobacco-heating cigarette or snus: Part 2. Biomarkers of exposure. [2019]

10. United States pubmed.ncbi.nlm.nih.gov

Disparities in secondhand smoke exposure--United States, 1988-1994 and 1999-2004. [2022]