Biomonitoring - Cotinine
In nonsmokers, cotinine is a marker of exposure to environmental tobacco smoke, commonly referred to as secondhand smoke. Secondhand smoke can cause sudden infant death syndrome (SIDS), acute lower respiratory infections, ear problems, and more severe asthma in children. Exposure to secondhand smoke also slows lung growth in children.
On this page:
Indicators
B5: Cotinine in nonsmoking children
Web update: 2023
Key Information
- In 2017-2020, the median level of cotinine in the blood of nonsmoking children was 0.02 ng/mL, a 92% decrease from 0.25 ng/mL in 1988-1991. The median represents the midpoint of exposure.
- In 2017-2020, the 95th percentile level of cotinine in the blood of nonsmoking children was about 2 ng/mL, a decrease from 3.2 ng/mL in 1988–1991. The 95th percentile represents higher exposure.
- In nearly every period measured, children had higher cotinine exposures than women of child-bearing age.
Data Characterization
Data for this indicator are obtained from an ongoing continuous survey conducted by the National Center for Health Statistics.
Survey data are representative of the U.S. civilian noninstitutionalized population.
Cotinine is measured in blood samples obtained from individual survey participants.
B6: Cotinine in nonsmoking women
Web update: 2023
Key Information
- In 2017-2020, the median level of cotinine in the blood of nonsmoking women of child-bearing age was 0.02 ng/mL, a decrease of 90% from 0.21 ng/mL in 1988-1991. The median represents the midpoint of exposure.
- In 2017-2020, the 95th percentile level of cotinine in the blood of highly-exposed women was 1.4 ng/mL, a decrease from 2.6 ng/mL in 1988–1991. The 95th percentile represents higher exposure.
Data Characterization
Data for this indicator are obtained from an ongoing continuous survey conducted by the National Center for Health Statistics.
Survey data are representative of the U.S. civilian noninstitutionalized population.
Cotinine is measured in blood samples obtained from individual survey participants.
About the Cotinine Indicators
In nonsmokers, cotinine is a marker of exposure to environmental tobacco smoke, commonly referred to as secondhand smoke.
Secondhand smoke is a complex mixture of gases and particles and includes smoke from burning cigarettes, cigars, and pipe tobacco, as well as exhaled smoke. Children can be exposed to secondhand smoke in their homes or in places where people are allowed to smoke, such as some restaurants in some locations throughout the United States.
According to the U.S. Surgeon General, there is no safe level of exposure to secondhand smoke, and breathing even a small amount can be harmful. The Surgeon General has concluded that exposure to secondhand smoke causes sudden infant death syndrome (SIDS), acute lower respiratory infections, ear problems, and more severe asthma in children. Exposure to secondhand smoke also slows lung growth in children.
The exposure of a pregnant woman to secondhand smoke can also be harmful to her developing fetus. The Surgeon General has determined that exposure of pregnant women to secondhand smoke causes a small reduction in birth weight and may result in preterm delivery.
For historic and contextual information about cotinine and these indicators, see the Cotinine section of America's Children and the Environment, Third Edition (pdf) .
Data Sources and Methods - Cotinine
The National Center for Health Statistics, a division of the Centers for Disease Control and Prevention, conducts the National Health and Nutrition Examination Surveys (NHANES), a series of U.S. national surveys of the health and nutrition status of the noninstitutionalized civilian population. Interviews and physical examinations are conducted with approximately 10,000 people in each two-year survey cycle. The survey measures cotinine levels in blood serum samples collected from NHANES participants. These indicators focus on both children and women of child-bearing age because of concern for potential adverse effects in children exposed to secondhand smoke and in children born to women who have been exposed to secondhand smoke. Both indicators present cotinine levels for non-tobacco-users only.
- Detailed Methods for Indicators B4 and B5 (pdf)
- Metadata for National Health and Nutrition Examination Survey (NHANES)
Related Links
- U.S. EPA: Health Effects of Exposure to Secondhand Smoke
- Centers for Disease Control and Prevention (CDC): Health Effects of Secondhand Smoke
- Centers for Disease Control and Prevention (CDC): National Report on Human Exposure to Environmental Chemicals
- National Cancer Institute (NCI): Secondhand Smoke and Cancer