Child Salivary Cotinine Levels Related to Neighborhood Deprivation and Tobacco and Alcohol Retail Outlets.

The overall objective of this study was to better understand the neighborhood conditions, including neighborhood deprivation and tobacco and alcohol retail outlets, related to objectively measured secondhand exposure to tobacco smoke among children. This study employed a cross-sectional study design of biological samples, surveys, and geospatial data from children (median [inter-quartile range] 5 [4, 7] years) in the Newborn Epigenetics Study between 2006 and 2012. Variation in salivary cotinine levels in children was examined in relation to contemporaneous existence of retail outlets, including tobacco retail outlets (TRO), alcohol retail outlets (ARO), those that sell both tobacco and alcohol (TAROs), and neighborhood deprivation index (NDI) using American Community Survey data from 2014 to 2018, adjusting for individual-level variables including child race, gender, age, and maternal education and smoking. A Bayesian index modeling approach was used to estimate the relationship between child cotinine levels and outlet density and NDI using seven socioeconomic variables at the census tract level and to determine the most important variables related to secondhand smoke exposure. Significant and positive associations between counts of outlets and child cotinine in crude models (odds ratios 1.023, 1.033, 1.044 for a one-outlet increase, respectively) were observed. Associations with outlet density were attenuated when adjusting for important contextual- and individual-level variables including race and maternal education and smoking. Results support multi-level strategies to help reduce secondhand smoke exposure in children. To be effective, such efforts should aim to reduce maternal smoking, but also address tobacco and alcohol retail outlet density, especially in higher poverty neighborhoods.