Protocol - Biomarker of exposure to nicotine-containing products - Saliva
Description
This is the laboratory protocol for measuring salivary cotinine. It is used to screen for smoking status and to estimate exposure to secondhand smoke (SHS).
A biospecimen is collected from the respondent to measure cotinine, a marker of either smoking or environmental tobacco smoke exposure. One of the most common methods of collection is via a urine sample obtained from the respondent. Cotinine in saliva is best measured by liquid chromatography - tandem mass spectrometry (LC-MS/MS).
Specific Instructions
The gold standard to measure cotinine levels is blood. Collection of saliva is less invasive and saliva and blood levels of cotinine are highly correlated. Choosing saliva over serum or plasma is based on convenience for investigator, no need for phlebotomist, no pain for subjects, and can be collected at home and mailed to the researcher.
The Tobacco Regulatory Research Panel (TRRP) recommends oral suctioning infants and toddlers for saliva if a sample is needed for cotinine measurement. The TRRP also recommends continuing collection until at least 2-3 ml of saliva (excluding foam) have been collected, marking the tubes with a line to which the saliva should be collected.
Because of the sensitive nature of this assay, analysts cannot be actively using tobacco products, and measurements must be performed in a smoke-free environment.
Safety Precautions: Personal protective equipment (PPE) including eye protection, gloves and suitable protective clothing when used to extract and process samples
Availability
Protocol
Collect saliva by having subjects expectorate into a vial while stimulating saliva flow with one of the three methods employed in previous studies: (a) sucking on a lemon candy, (b) dissolving a sugar cube in the mouth, or (c) chewing on parafilm. Approximately 2-3 minutes is required to collect each saliva sample.
At least 3 mL should be provided, to have enough sample volume for a repeat analysis if needed. Samples should be stored at -20° C.
Liquid chromatography – tandem mass spectrometry (LC-MS/MS) is the preferred method to accurately measure cotinine in saliva samples, especially when used to assess secondhand smoke exposure. (See source references for details.) The limit of quantitation is 0.02 ng/mL.
Personnel and Training Required
Training on saliva collection and shipping techniques. Laboratory training in the use of liquid chromatography and tandem mass spectrometry is required, as well as general laboratory training on the safe use of chemicals and solvents.
Equipment Needs
Saliva collection and shipping kits. This method requires high-performance liquid chromatography and tandem mass spectrometry on a triple quadrupole mass spectrometer.
Requirements
| Requirement Category | Required |
|---|---|
| Major equipment | Yes |
| Specialized training | Yes |
| Specialized requirements for biospecimen collection | No |
| Average time of greater than 15 minutes in an unaffected individual | No |
Mode of Administration
Bioassay
Lifestage
Child, Adolescent, Adult, Senior, Pregnancy
Participants
All participants who can provide a saliva sample.
Selection Rationale
Saliva is easy to obtain through a non-invasive method and was chosen for this reason. Collection of saliva is less invasive and saliva and blood levels of cotinine are highly correlated. Choosing saliva over serum or plasma is based on convenience for investigator, no need for phlebotomist, no pain for subjects, and can be collected at home and mailed to the researcher.
There are other assays (e.g., gas chromatography (GC), gas chromatography mass spectrometry (GC-MS), radioimmunoassay and enzyme-linked immunosorbent assays) used to measure cotinine but liquid chromatography – tandem mass spectrometry (LC-MS/MS) is preferred, especially when used to assess secondhand smoke exposure.
Liquid chromatography – tandem mass spectrometry (LC-MS/MS) is the preferred method for determination of cotinine in saliva (see source references 1,2) and other biological fluids, especially for measuring concentrations in non-smokers for exposure to SHS and THS.
Language
English
Standards
| Standard | Name | ID | Source |
|---|
Derived Variables
None
Process and Review
The Tobacco Regulatory Research (TRR) Content Expert Panel (CEP) reviewed the measures in the Tobacco Regulatory Research collection in February 2024.
Guidance from the TRR CEP includes:
- Replaced protocol
- New Data Dictionary
Previous version in Toolkit archive (link)
Protocol Name from Source
Determination of cotinine in saliva using liquid chromatography - tandem mass spectrometry (LC-MS/MS)
Source
Bernert JT Jr, McGuffey JE, Morrison MA, Pirkle JL. Comparison of serum and salivary cotinine measurements by a sensitive high-performance liquid chromatography-tandem mass spectrometry method as an indicator of exposure to tobacco smoke among smokers and nonsmokers. Anal Toxicol. 2000 Jul-Aug;24(5):333-9. doi: 10.1093/jat/24.5.333. PMID: 10926356
Jacob P 3rd, Yu L, Duan M, Ramos L, Yturralde O, Benowitz NL. Determination of the nicotine metabolites cotinine and trans-3-hydroxycotinine in biologic fluids of smokers and non-smokers using liquid chromatography-tandem mass spectrometry: biomarkers for tobacco smoke exposure and for phenotyping cytochrome P450 2A6 activity. J Chromatogr B Analyt Technol Biomed Life Sci. 2011 Feb 1;879(3-4):267-76. doi: 10.1016/j.jchromb.2010.12.012. Epub 2010 Dec 21. PMID: 21208832, PMC3050598.
Rose J, Levin E, and Benowitz N. Saliva Nicotine as an Index of Plasma Levels in Nicotine Skin Patch Users. Therapeutic Drug monitoring. 1993; 15: 431-435.
General References
Avila-Tang E, Al-Delaimy WK, Ashley DL, Benowitz N, Bernert JT, Kim S, Samet JM, Hecht SS. (2013). Assessing secondhand smoke using biological markers. Tob Control, 22(3): 164-871.
Breimer DD, Danhof M. Saliva: a fluid for measuring drug concentrations. Pharm Int 1980: 1:9-11.
Jacob P, Wilson M, Benowitz, N. Improved gas chromatographic method for the determination of nicotine and cotinine in biologic fluids. J Chromatogr 1981: 222: 61-70.
Pirkle, J. L., Flegal, K. M., Bernert, J. T., Brody, D. J., Etzel, R. A., & Maurer, K. R. (1996). Exposure of the US population to environmental tobacco smoke. The Third National Health and Nutrition Examination Survey, 1988 to 1991. JAMA, 275, 1233-124
Rose JE, Herskovice JE, Trilling Y, Jarvik ME. Transdermal nicotine reduces cigarette craving and nicotine preference. Clin Pharmacol Ther 1985; 38: 450-6.
St. Helen, G., Novalen, M., Heitjan, D.F. (2012). Reproducibility of the Nicotine Metabolite Ratio in Cigarette Smokers. Cancer Epidemiology, Biomarkers & Prevention, 21(7) 1105-1114.
Protocol ID
91705
Variables
Export Variables| Variable Name | Variable ID | Variable Description | dbGaP Mapping |
|---|
Measure Name
Biomarker of exposure to nicotine-containing products
Release Date
May 3, 2024
Definition
Cotinine is a major metabolite of nicotine and is an indicator of exposure to nicotine from tobacco or other nicotine containing products.
Purpose
To assess smoking and environmental tobacco smoke (ETS) exposure by measuring cotinine, a metabolite of nicotine. To screen for tobacco use and quantity and to estimate exposure to secondhand smoke (SHS) and all tobacco exposure. Also used as an outcome measure in smoking cessation trials to determine if an individual has quit smoking.
Keywords
Biomarker of exposure to nicotine-containing products - saliva, cotinine, Respiratory, Liquid Chromatography – Tandem mass spectrometry (LC-MS/MS), LC-MS/MS
Measure Protocols
| Protocol ID | Protocol Name |
|---|---|
| 91704 | Biomarker of exposure to nicotine-containing products - Urine |
| 91705 | Biomarker of exposure to nicotine-containing products - Saliva |
| 91706 | Biomarker of exposure to nicotine-containing products - Serum |
Publications
There are no publications listed for this protocol.