A Phase 4 interventional study of Wood Smoke (Lodgepole Pine) exposure and Filtered Air exposure in This Study Will Evaluate the Effects of Woodsmoke Exposures and Advil in Healthy Adults, sponsored by University of British Columbia. Not yet recruiting at 1 site in Canada. Open to participants aged 19 Years to 80 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-11-09.
Sponsored by University of British Columbia · Phase 4, Interventional, and Prevention
The goal of this clinical exposure study is to investigate the inflammatory and airway responses to controlled wood smoke exposure, a model for wildfire-related air pollution, and how these responses change with Otrivin Natural Saline Nasal Spray and Advil Extra Strength Liqui-Gels 400mg, used within their approved indications for clearing the nasal passages and the relief of pain and inflammation, respectively, in healthy adult participants. The main questions it aims to answer are:
Wildfire smoke is becoming an increasing source of air pollution and can contain substances that may affect health. Exposure to air pollution, including wildfire smoke, can cause inflammation and irritation in the airways and may contribute to symptoms such as coughing, throat irritation, difficulty breathing, and inflammation or pain in the eyes and nose. However, more research is needed to understand how exposure to wildfire smoke affects the nose and lungs.
Non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen (the active ingredient in Advil), are commonly used to reduce pain and inflammation. Some previous research suggests that NSAIDs, used as a model anti-inflammatory medication, may reduce certain effects of air pollution exposure. However, it is not yet known whether the inflammation caused by wood smoke, as a model for wildfire-related air pollution, is modulated with Advil use.
It is also not known whether the irritating effects of wood smoke air pollution exposure on the nose are altered when Otrivin is used to wash the nose. The purpose of this study is to investigate how controlled wood smoke exposure affects the nose and lungs and whether Advil and Otrivin saline nasal spray, used within their indications, alter these effects. The information collected in this study may contribute to future research on the health effects of wildfire smoke and potential ways to reduce these effects.
Participants will be asked to complete an initial baseline screening, followed by four study arms, with each study arm consisting of two study visits. During the first visit of each study arm, participants will undergo a controlled 2-hour exposure to either filtered air or wood smoke and will receive either Advil or a placebo. The second visit of each study arm will occur approximately 24 hours after the exposure visit. The four study arms will involve different combinations of exposure and Advil/Placebo, but the order in which the study arms are completed will be determined by chance and not revealed to the participants or the clinical study team. There will be at least 4 weeks between each study arm to allow time for the previous exposure to wash out.
University of British Columbia is the lead sponsor of 1,339 studies on the registry; 259 are open to participants now.
Of its 6 completed or terminated interventional studies of FDA-regulated products, 1 (17%) have results posted.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Chronic obstructive pulmonary disease: long-term lung disease that makes it hard to breathe out, including emphysema and chronic bronchitis.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Postmenopausal
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
COPD
Chronic obstructive pulmonary disease: long-term lung disease that makes it hard to breathe out, including emphysema and chronic bronchitis.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will be exposed to high-efficiency particulate air (HEPA) filtered air for 2 hours, and will take a placebo both before, and 3, 10, 22 hours after.
Other: Filtered Air exposure · Drug: Placebo Pill
Participants will be exposed to high-efficiency particulate air (HEPA) filtered air for 2 hours and will take Advil (Ibuprofen 400mg) both before, and 3, 10 and 22 hours after.
Other: Filtered Air exposure · Drug: Ibuprofen (Advil 400 mg x 4)
Participants will be exposed to wood smoke, standardized to 500µg/m3 of PM2.5, for 2 hours and will take a placebo both before, and 3, 10 and 22 hours after.
Other: Wood Smoke (Lodgepole Pine) exposure · Drug: Placebo Pill
Participants will be exposed to wood smoke, standardized to 500µg/m3 of PM2.5, for 2 hours and will take Advil (Ibuprofen 400mg) both before, and 3, 10 and 22 hours after.
Other: Wood Smoke (Lodgepole Pine) exposure · Drug: Ibuprofen (Advil 400 mg x 4)
Woodsmoke will be freshly generated using a furnace tube burning dried, ground lodgepole pine (Pinus contorta) to achieve a nominal concentration of 500µg/m3 of PM2.5 (particulate matter with an aerodynamic diameter of less than or equal to 2.5 micrometres).
Air will undergo high-efficiency particulate air filtration to generate clean Filtered Air.
Placebo pills produced to resemble Advil Extra Strength Liqui-Gels will be given at baseline and at 3, 10 and 22 hours following exposures.
400mg of the non-steroidal anti-inflammatory drug Ibuprofen in the form of Advil Extra Strength Liqui-Gels given at baseline and at 3, 10 and 22 hours following exposures.
Effects of wood smoke on airway inflammation with Advil and Otrivin: FeNO
Measurement of fractional exhaled nitric oxide (FeNO).
Time frame: Comparison of the different arms over the span of 5 months.
Effects of wood smoke on airway inflammation with Advil and Otrivin: Cytokines and Oxylipins
An inflammation matrix will be generated, including data from nasal inflammatory cytokines and oxylipins, with independent collection from each nostril.
Time frame: Comparison of the different arms over the span of 5 months.
Effects of wood smoke exposure on airflow and resistance in the airways with Advil and Otrivin: PNIF
Measure nasal patency using peak nasal inspiratory flow (PNIF) analysis.
Time frame: Comparison of the different arms over the span of 5 months.
Effects of wood smoke exposure on airflow and resistance in the airways with Advil and Otrivin: Oscillometry
Determine small airways function/resistance using oscillometry.
Time frame: Comparison of the different arms over the span of 5 months.
Effects of wood smoke on airway symptoms and perception with Advil and Otrivin
The Symptoms and Perception questionnaire (see https://particleandfibretoxicology.biomedcentral.com/articles/10.1186/s12989-022-00506-6#Sec15) will be completed.
Time frame: Comparison of the different arms over the span of 5 months.
Effects of wood smoke on systemic inflammatory responses with Advil and Otrivin
An inflammation matrix will be generated, including data from urinary isoprostanes and eicosanoid metabolites.
Time frame: Comparison of the different arms over the span of 5 months.
Plan to share: Undecided
No publications or documents are linked to this record.
Start is estimated for Dec 2026; primary completion for Dec 2028, 24 months later.
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From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is not yet recruiting, as verified in Nov 2026. You cannot join it, but the record below documents what was studied.
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