From Centers for Disease Control and Prevention, Office on Smoking and Health

This study assessed the impact of defining secondhand smoke (SHS) exposure among nonsmokers using an expanded serum cotinine range among a nationally representative sample of U.S. nonsmokers aged 3 years or older.  This study found that expanding the serum cotinine range from 0.05-10 ng/mL to 0.015-10 ng/mL more than doubles the estimated proportion of U.S. nonsmokers exposed to SHS.  In contrast to a serum cotinine range of 0.05-10 ng/mL, a cotinine range of 0.015-10 ng/mL suggests that progress has been made in reducing population-level SHS exposure during 2011-2018, especially among nonsmokers experiencing lower exposure levels.  Additional research will be important to help inform potential future modifications to the currently established definition of 0.05-10 mg/mL to best inform public health policy, planning, and practice.

However irrespective of the cotinine range used, a sizable portion of the U.S. population remains exposed to SHS, and exposure is especially high among certain population subgroups, including children and adolescents, non-Hispanic Blacks, those living in poverty, those with a high school education or less, those living in rental housing, and those living with someone who smoked inside the home.  Taken together, these findings underscore the importance of adopting evidence-based strategies to protect all people from SHS exposure.

This article is available online at: https://www.ajpmonline.org/article/S0749-3797(21)00232-4/fulltext