Plain English Summary
Background and study aims
We are carrying out a study of 40 volunteers to see if face masks reduce the amount of air pollutants in urine. These chemicals measure how much air pollution a person has breathed over the past one or two days. According to the United Nations, Hanoi is one of the top six cities with the highest amount of pollution in the world. Air pollution is believed to cause different kinds of diseases in people, especially in developing countries. The long-term goal of this study is to see if the R95 face mask can reduce the amount of respiratory diseases (diseases that make it hard to breathe) caused by air pollution. The immediate goal of the study is to investigate whether the face mask reduces the amount of air pollution breathed by 40 healthy volunteers.
Who can participate?
This study aims to recruit 40 healthy adult volunteers (20 males and 20 females) who work outside on the street for at least 4 hours every 24 hours. Examples of people that work on the street include motorbike drivers, street vendors, gas station workers and construction workers.
What does the study involve?
The study will last two weeks. All volunteers will begin the study at the same time. There will be two different schedules describing when and for how long volunteers should wear their masks. Volunteers will be randomly assigned to one of these two schedules. Certain chemicals in urine measure how much air pollution a person has inhaled during the past one or two days. Urine samples will be collected on Tuesday and Friday afternoons, and these chemicals will be measured to determine how much air pollution the volunteer has breathed. Two study employees will visit volunteers at their workplace to check whether or not volunteers are actually wearing their face masks. Study employees will visit volunteers without telling them in advance and at random times. Study employees will remind volunteers to wear their masks by sending them text messages each day.
What are the possible benefits and risks of participating?
The study will pay participants 3 USD in Vietnamese dollars for each urine specimen and 1 USD for each day participants write in their diary. If participants follow all instructions correctly for the 15 days of the study, they will receive 30 USD in Vietnamese dollars.
Where is the study run from?
The study is run by researchers at the Oxford University Clinical Research Unit (OUCRU) Viet Nam, in association with the London School of Hygiene and Tropical Medicine (LSHTM) and the Hospital for Tropical Diseases in Ho Chi Minh City.
When is study starting and how long is it expected to run for?
The study ran from July to October 2009 for a total of 3 months. The study has been completed.
Who is funding the study?
The Wellcome Trust (UK).
Who is the main contact?
The Clinical Trials Unit at the Oxford University Clinical Research Unit Viet Nam. +84839241983
Trial website
Additional identifiers
EudraCT number
ClinicalTrials.gov number
Protocol/serial number
03 09
Study information
Scientific title
Respirator N95 masks to prevent the inhalation of urban air pollutants: a pilot intervention study in Hanoi, Vietnam
Acronym
01AV
Study hypothesis
To test if wearing the R95 Particulate Respirator face mask, produced by 3M reduces levels of pollution exposure biomarkers in 40 healthy volunteers.
Ethics approval
Oxford Tropical Research Ethics Committee approved on the 29th January 2009 (ref: 03/09)
Study design
Single centre open intervention cross-over study
Primary study design
Interventional
Secondary study design
Non randomised controlled trial
Trial setting
Other
Trial type
Quality of life
Patient information sheet
Not available in web format, please use the contact details below to request a patient information sheet
Condition
Air pollution & respiratory problems
Intervention
The intervention consists of wearing a R95 particulate respirator (3M, 9900 series) on assigned days for a 2-week period. All volunteers start at the same time and will be randomly allocated to a specific scheme on when and when not to wear the study mask. Two mask-wearing sequences exist, being ABBA or BAAB, with the following routine:
A. Two days activated carbon mask during transportation and working hours
B. Two days with no mask
Urine samples will be taken at baseline and every three days of the study. Levels of polycyclic aromatic hydrocarbons metabolites in the urine will be tested. A daily diary will be kept detailing respiratory symptoms (sneezing, nasal congestion, nasal discharge, throat pain, cough, dyspnoea, eye irritation, other), comfort of the mask, general 'well being', fever, headache, nausea, motorbike accident, wearing glasses, food types consumed (any grilled food), time spent outside on the street.
Intervention type
Other
Phase
Not Applicable
Drug names
Primary outcome measures
Concentration of exhaust and smoking metabolites in urine, with 1-hydroxypyrene as the primary endpoint metabolite.
Outcomes will be measured at day 0 (baseline), day 4, day 7, day 11 and day 14.
Secondary outcome measures
Other metabolites in the urine including 1-hydroxynaphthalene, 2-hydroxynaphthalene, 2-hydroxyfluorene, 3-hydroxyfluorene, 9-hydroxyfluorene, 1-hydroxyphenanthrene, 2-hydroxyphenanthrene, 3-hydroxyphenanthrene, 4-hydroxyphenanthrene, Cotinine and Creatinine.
Outcomes will be measured at day 0 (baseline), day 4, day 7, day 11 and day 14.
Overall trial start date
01/07/2009
Overall trial end date
01/10/2009
Reason abandoned
Eligibility
Participant inclusion criteria
Healthy male and female Vietnamese volunteers over 18 years of age
Participant type
Patient
Age group
Adult
Gender
Both
Target number of participants
40
Participant exclusion criteria
1. Smoking tobacco
2. Cooking at home with biomass fuel
3. Not willing to stop eating grilled food during study period of 2 weeks
4. Home address is at a main city road
5. Not willing to wear a face mask
6. Type of work prohibits wearing a mask (e.g. regular conversation)
7. No direct access to mobile phone
8. Not able to read or write
9. Not able to complete the study for other reasons
10. Respirator mask does not fit (determined by fitness test)
11. No informed consent
Recruitment start date
01/07/2009
Recruitment end date
01/10/2009
Locations
Countries of recruitment
Viet Nam
Trial participating centre
Oxford University Clinical Research Unit
Hanoi
00000
Viet Nam
Sponsor information
Organisation
University of Oxford (UK)
Sponsor details
Centre for Tropical Medicine
CCVTM
Churchill Hospital
Old Road
Headington
Oxford
OX3 7LJ
United Kingdom
Sponsor type
University/education
Website
Funders
Funder type
Charity
Funder name
The Wellcome Trust (UK) (ref: 077078)
Alternative name(s)
Funding Body Type
Funding Body Subtype
Location
Results and Publications
Publication and dissemination plan
Not provided at time of registration
Intention to publish date
Participant level data
Not provided at time of registration
Results - basic reporting
Publication summary
1. 2012 results in http://www.ncbi.nlm.nih.gov/pubmed/23013369
Publication citations
-
Results
Wertheim HF, Ngoc DM, Wolbers M, Binh TT, Hải NT, Loan NQ, Tú PT, Sjodin A, Romanoff L, Li Z, Mueller JF, Kennedy K, Farrar J, Stepniewska K, Horby P, Fox A, Bao ND, Studying the effectiveness of activated carbon R95 respirators in reducing the inhalation of combustion by-products in Hanoi, Vietnam: a demonstration study., Environ Health, 2012, 11, 72, doi: 10.1186/1476-069X-11-72.