Tobacco Exposure Biomarker (Carbon Monoxide Metabolite) – Serum
This test measures a breakdown product of tobacco exposure, often used to assess recent smoking or environmental tobacco smoke (ETS) exposure.
["Helps track exposure to tobacco products in your bloodstream."]
Key facts at a glance
- LOINC
- 102630-1
- Short code
- Tobacco IgE RAST
- Synonyms
- Tobacco IgE RAST
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 10
- Ref high
- 40
- Critical range
- — – 500 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- rast
- CPT
- 84484
- SNOMED
- 302774002
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What This Test Measures
The test detects a specific metabolite linked to carbon monoxide, a gas produced when tobacco is burned. This metabolite appears in your blood after exposure to tobacco smoke, whether from smoking or secondhand exposure. The presence of this marker can indicate recent exposure levels, though it may not reflect long-term smoking history alone.
Why Your Doctor Might Order This Test
Doctors may request this test to evaluate exposure to tobacco products, especially in patients with suspected secondhand smoke inhalation, occupational smoke exposure, or those undergoing monitoring for tobacco dependence treatment. It can also be part of a broader assessment for conditions linked to tobacco use, such as respiratory issues or cardiovascular risks.
Sample Collection and Preparation
A blood sample is drawn from a vein in your arm. The blood is then processed to separate serum (the liquid part after clotting), which is sent for analysis. This test is typically performed on fresh serum samples, and results are compared to a baseline or reference range provided by the lab.
What to Expect Before the Test
No special preparation is needed for this test. You may eat and drink normally on the day of testing, but inform your healthcare provider if you are taking any medications that could interfere with blood analysis.
Reference range
Adult: 10-40 U/LN/A
No special preparation required. Avoid fatty meals before the test if possible.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
This test provides a snapshot of recent tobacco exposure but does not measure long-term smoking habits. Elevated levels may suggest recent exposure to tobacco smoke, which can be harmful to health. It is often used alongside other assessments, such as cotinine levels (another tobacco exposure marker), to better understand exposure patterns. Results should be interpreted by a healthcare professional in the context of your overall health and medical history.
Short name
CO Metabolite (Serum)
Frequently asked questions
How long does it take to get results from this test?
Can this test detect secondhand smoke exposure?
Will this test show if I’ve smoked in the past?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 17, 2026. · Read our editorial policy