Pulmonary and Systemic Effects of Exposure to Wood Smoke

NCT ID: NCT03302117

Last Updated: 2017-10-04

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

UNKNOWN

Total Enrollment

20 participants

Study Classification

OBSERVATIONAL

Study Start Date

2017-06-14

Study Completion Date

2018-02-08

Brief Summary

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

This is study is to assess pulmonary and systemic effects of exposure to wood smoke. Healthy volunteers will be expose under two different occasion to wood smoke and filtered air under two separated occasions with an interval of 3 weeks in-between. The aim of this study was to determine whether exposure to wood smoke from incomplete combustion would elicit airway inflammation in humans.

Detailed Description

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

Brief Summary This is study is to assess pulmonary and systemic effects of exposure to wood smoke. Healthy volunteers will be expose under two different occasion to wood smoke and to filtered air for two hours under two separated occasions with an interval of 3 weeks in-between. The aim of this study was to determine whether exposure to wood smoke from incomplete combustion would elicit airway inflammation in humans.

Detailed description Air pollution is associate with increased pulmonary and cardiovascular mobility and mortality. UNICEF recently published a report highlighting the health effects of air pollution from a global perspective, with particular focus on pediatrics population. Overall, air pollution is estimated to cause about 7 million deaths each year in the world, of which about 600,000 of these apply to children under 5 years (1). Indoor and outdoor air pollutants are the 3rd and 9th most common cause of death. Nearly 3 billion people are dependent on biomass for daily needs, Exposure to wood smoke has been linked to elevated asthma prevalence, increased asthma symptoms in children and adults, as well as higher hospital admissions due to asthma attacks. The association between long-term indoor wood smoke exposure and the development and worsening of chronic obstructive pulmonary disease has been shown to be strong in many epidemiological studies (2,3), and the risk for chronic obstructive pulmonary disease development has been estimated to be more than doubled for solid fuel smoke compared with smoke from other types of fuels (4). Exposure to smoke from combustion of wood and other biomass fuels has also been shown to increase the risk for acute and chronic lower respiratory tract infections, including pneumonias and tuberculosis. The aim of the current study was to further characterize the respiratory and systemic effects of exposure to wood smoke emitted from incomplete soot-rich combustion in a wood stove.

The study will be performed in a randomized, double blind, crossover fashion. Twenty healthy subjects will be exposed on two occasions, under well-controlled situations, to filtered air and wood smoke in an exposure chamber at Thermochemical Energy Conversion Laboratory at Umeå University. The chamber is made of stainless steel, has a volume of a 15.3 m3 and an air exchange rate of around three times per hour and has been previously described (5). The mean particle mass concentration of wood smoke will be 450 μg/m3. The exposures will last for two hours, during which the subject will perform intermittent exercise on a bicycle ergometer, alternate with rest at 15-minute intervals, to achieve an average minute ventilation of 20 L/min/m2 body surface. During the exposures, symptoms well be recorded according to the modified Borg scale, as described previously (6). Spirometry and impulse oscillometry system (IOS) will be used to assess the lung function at baseline and immediately after each exposure. Bronchoscopy will be performed 6 hours after each exposure. Differential cell counts and soluble components will be analyzed in peripheral blood sampling at baseline and 6 hours after each exposure.

Conditions

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

Pulmonary Inflammation Cytotoxicity

Study Design

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

Observational Model Type

CASE_CROSSOVER

Study Time Perspective

PROSPECTIVE

Interventions

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

Wood smoke exposure

Healthy volunteers will exposed to filtered air alternate with wood smoke generated from incomplete wood smoke combustion to assess the local and systemic effect of theses exposures

Intervention Type OTHER

Eligibility Criteria

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

Inclusion Criteria

* Healthy volunteers
* Non-smoker
* Non-allergic

Exclusion Criteria

* Diabetes Mellitus
* Renal failure
* Ischemic heart disease
* History of hematological disease
* Previous smoking.
Minimum Eligible Age

20 Years

Maximum Eligible Age

40 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

Yes

Sponsors

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

Umeå University

OTHER

Sponsor Role lead

Responsible Party

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

Responsibility Role SPONSOR

Principal Investigators

Learn about the lead researchers overseeing the trial and their institutional affiliations.

Ala Muala, MD, PhD

Role: PRINCIPAL_INVESTIGATOR

Department for Public Health and Clinical Medicine

Locations

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

Department for Public Health and Clinical Medicine

Umeå, , Sweden

Site Status RECRUITING

Countries

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

Sweden

Central Contacts

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

Ala Muala, MD, PhD

Role: CONTACT

+46907851785

Thomas Sandström, MD, PhD

Role: CONTACT

+46907852516

Facility Contacts

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

Ala Muala, MD, PhD

Role: primary

+467851784

Thomas Sandström, MD, PhD

Role: backup

+46907852516

References

Explore related publications, articles, or registry entries linked to this study.

Friedrich MJ. UNICEF Reports on the Impact of Air Pollution on Children. JAMA. 2017 Jan 17;317(3):246. doi: 10.1001/jama.2016.19034. No abstract available.

Reference Type BACKGROUND
PMID: 28114563 (View on PubMed)

Po JY, FitzGerald JM, Carlsten C. Respiratory disease associated with solid biomass fuel exposure in rural women and children: systematic review and meta-analysis. Thorax. 2011 Mar;66(3):232-9. doi: 10.1136/thx.2010.147884. Epub 2011 Jan 19.

Reference Type BACKGROUND
PMID: 21248322 (View on PubMed)

Hu G, Zhou Y, Tian J, Yao W, Li J, Li B, Ran P. Risk of COPD from exposure to biomass smoke: a metaanalysis. Chest. 2010 Jul;138(1):20-31. doi: 10.1378/chest.08-2114. Epub 2010 Feb 5.

Reference Type BACKGROUND
PMID: 20139228 (View on PubMed)

Kurmi OP, Semple S, Simkhada P, Smith WC, Ayres JG. COPD and chronic bronchitis risk of indoor air pollution from solid fuel: a systematic review and meta-analysis. Thorax. 2010 Mar;65(3):221-8. doi: 10.1136/thx.2009.124644.

Reference Type BACKGROUND
PMID: 20335290 (View on PubMed)

Unosson J, Blomberg A, Sandstrom T, Muala A, Boman C, Nystrom R, Westerholm R, Mills NL, Newby DE, Langrish JP, Bosson JA. Exposure to wood smoke increases arterial stiffness and decreases heart rate variability in humans. Part Fibre Toxicol. 2013 Jun 6;10:20. doi: 10.1186/1743-8977-10-20.

Reference Type BACKGROUND
PMID: 23742058 (View on PubMed)

Rudell B, Ledin MC, Hammarstrom U, Stjernberg N, Lundback B, Sandstrom T. Effects on symptoms and lung function in humans experimentally exposed to diesel exhaust. Occup Environ Med. 1996 Oct;53(10):658-62. doi: 10.1136/oem.53.10.658.

Reference Type BACKGROUND
PMID: 8943829 (View on PubMed)

Other Identifiers

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

WSIII

Identifier Type: -

Identifier Source: org_study_id