s25 2 how do we measure secondhand smoke- erika avila-tang
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测量二手烟TRANSCRIPT
Dr. Erika Avila Tang
Department of Epidemiology
Institute for Global Tobacco Control
How do we Measure Secondhand Smoke Exposure?
FAMRI Expert SHSe Assessment
Goal:
To catalogue the approaches for Secondhand Smoke exposure (SHSe) assessment
Provide a set of uniform methods for future use to facilitate comparisons of findings across studies
Comprehensive topic assessments on:
Questionnaires and self-reported methods
Biological samples
Environmental samples
Flight Attendant Medical Research Institute (FAMRI) Centers of Excellence
American Academy of Pediatrics Julius B. Richmond, Illinois, USA
Johns Hopkins University, Maryland, USA
University of California, San Francisco Bland Lane, California, USA
More than 20 researchers on SHSe assessment involved
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Why would we want to measure SHSe?
SHSe is a key element of tobacco control
research and implementation worldwide
To estimate the SHSe overall burden of disease
To determine the risks associated with SHSe
To assess population trends in support of and
evaluate tobacco control policies
To support and evaluate behavioral interventions
Topic assessments
Questionnaires and self-reported methods
Biological samples
Environmental samples
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Self-reported methods of assessment
Questionnaires
Most commonly used
Inexpensive and feasible for large studies
Assessment of :
Current and long-term exposure
Time-activity patterns
Recall can be an issue
Diaries
Recall burden is reduced but respondent’s burden is increased
E.g. Report over the past day vs. past week/month
Higher awareness of instances of exposure
Accuracy: validity and reliability
Review of studies assessing the validity and/or
reliability of questions
Validation of questions against a “gold
standard”:
Air measurement
Biomarker
Reliability=repeatability
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Conclusions for questionnaires and self-
reported methods
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Reliable responses for SHSe in their lifetime, childhood, and current among adults.
For children, CPD from parents, in their presence, and in places
Research on testing the accuracy of questions are still needed
Current exposure for adults and children, including intensity and duration of exposure
Exposure at home, in transport, and in social settings
Collaboration of FAMRI CoEs: AAP Richmond, Johns Hopkins, and UCSF Bland Lane are testing questions in pilot studies to continue building a set of core questions
Topic assessments
Questionnaires and self-reported methods
Biological samples
Environmental samples
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Biomarkers
Tobacco-specific biomarkers
Cotinine
Reflects recent SHSe (t1/2 16 hours (average))
Nicotine/cotinine in hair or toenails
Reflects “longer exposure”: 1 cm of hair proximal to the
scalp ≈ last month’s exposure; 1 mm ≈ last month’s
exposure
NNAL (4-[methylnitrosamino]-1-[3-pyridyl]-1-butanol)
Reflects “longer exposure” (t1/2 up to 3 weeks)
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Biomarker- Cotinine
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Matrix Cut-off Pros Cons
Urine Non-invasive
50 ng/ml for higher SHSe
Higher concentrations than other matrices (higher sensitivity)
Need of facilities with privacy during collection
Difficulty for population-based or children studies
Need for creatinine clearance adjustment
Collect data on renal disease and some prescription drugs
Blood Invasive
12 ng/ml for higher SHSe
3 ng/ml for lower
SHSe
No adjustment required for hydration
Pregnant women have increased clearance rate
Difficulty for infants and young children
Lower sensitivity
Saliva Non-invasive
14 ng/ml for higher SHSe
Good for multiple measurements over a limited period of time
Potential issues with age, gender, race, oral pH, type of diet, dehydration, or drug treatment
Lower sensitivity
Biomarker- Nicotine/Cotinine
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Matrix Cut-off Pros Cons
Hair Non-invasive
0.8 ng/mg (Women)
0.2 ng/mg (Pregnant)
0.2 ng/mg (Children)
Easy to collect, ship, and store (room temperature ≤ 5 years)
Less affected by daily variability (fluctuating exposure, varying metabolism, and nicotine elimination)
Represents longer exposure
Scarcity of hair in infants and adults
Chemical hair treatments can reduce concentrations by 9%-30%
Age, gender, and race may play roles in determining hair nicotine concentrations
Toenails Non-invasive
Not available
Easy to collect, ship, and store (room temperature ≤ 20 years)
Overcomes day-to-day exposure variability
Represents longer exposure
Need for further research and population concentrations
Biomarker- NNAL
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Matrix Cut-off Pros Cons
Urine Not available
Related to a lung carcinogen
Represents longer exposure than cotinine (urine/blood/saliva)
Analytical expertise
Costly equipment
NNAL is carcinogenic and mutagenic, special lab handling
Further research needed
Topic assessments
Questionnaires and self-reported methods
Biological samples
Environmental samples
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Environmental measurements
Most widely used methods:
Nicotine: passive air monitor
Particulate matter (< 2.5µ (PM2.5)) monitor
Correlation between nicotine and PM when
measured in the same setting using a common
sampling period
An increase in 1 µg/m3 of nicotine concentration ≈ an
average increase of 10 µg/m3 of PM
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Air nicotine monitoring
Highly specific to tobacco smoke
Monitors (1-3) placed in each venue (hung from the
ceiling) for 5 to14 days
Filters are soaked in a bi-sodium sulfate solution that
captures nicotine on the filter
No expensive equipment to buy
up front and minimal operating
cost but requires lab analysis
Per sample laboratory costs
including the filter badge are
~$40-$100 USD
Particulate matter monitoring
Active, real-time monitor
Uses light scattering to measure particulate
matter concentrations (e.g. PM2.5)
Air quality standards makes easier
dissemination
Other causes of indoor air particles
High initial investment
~3,000 USD
Minimal operating cost
No per sample costs
Potential costs in labor for data analysis
Overall findings
Questionnaires are the most effective way to know if people are exposed – but not how much they are exposed
Research on testing the accuracy of questions are still needed
Choice of any SHSe assessment method depends on your needs
Study’s objectives, subjects, design and setting and funding
Selection of a biomarker will dependent on:
Issues of privacy, invasiveness, and subject’s age
The length of SHSe may result in selecting hair or toenails over bio-fluids
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Acknowledgements
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Melbourne Hovell
Andrew Hyland
Sungroul Kim
Jonathan Klein
Neil Klepeis
Robert McMillen
James Repace
Jonathan Samet
Jonathan Winickoff
Ana Navas-Acien
Lisa Hepp
Jessica Elf
Camille Madsen
Wael Al-Delaimy
Benjamin Apelberg
David Ashley
Erika Avila-Tang
Neil Benowitz
Thomas Bernert
Dana Best
Patrick Breysse
Michael Cummings
Geoffrey Fong
Lara Gundel
Kathie Hammond
Stephen Hecht