Environment/Climate Change
County-level radon and offspring wheezing and asthma Yijia Zhang* Yijia Zhang Elizabeth F Minsky Meghan Angley Shai Bejerano Brian J Smith Erin M Bell Diane L Putnick Edwina H Yeung Ka Kahe
Background The health risks of radon exposure beyond lung cancer are understudied. Maternal radon exposure, along with tobacco smoke, may be connected to offspring respiratory health.
Methods Upstate KIDS, a population-based prospective cohort consists of more than 5000 pregnancies from 57 counties in New York (excluding NYC). County-level radon exposure was measured by Lawrence Berkeley National Laboratory (LBL), categorized into ≥ 2 and <2 picocuries per liter (pCi/L), and linked to participants. Data on child wheeze was obtained from questionnaires completed around 4, 8, 12, 18, 24, 30, and 36 months of age and “persistent wheeze” defined as “yes” on two or more questionnaires. Asthma was defined as any maternal report of physician-diagnosed asthma or prescription of asthma medication or inhaler and assessed at two time points: up to 36 months and 7–9 years. Multivariable mixed-effects logistic regression was used to calculate adjusted odds ratios (aOR) and 95% confidence intervals (CI).
Results Maternal age averaged 30.7 years, and most were non-Hispanic White (80.0%). The median radon concentration is 1.29 pCi/L. Largely due to attrition, sample sizes for the analysis of wheezing, asthma up to 36 months, and asthma at 7–9 years were 5,683; 3,714; and 1,963, respectively. Radon was positively but not significantly associated with persistent wheeze (aOR = 1.25, 95% CI: 0.36–4.36). When stratifying by maternal smoking, the association remained in the same direction among never-smokers, but not smokers. The associations were also non-significant for both asthma outcomes.
Conclusions The ecological nature of the exposure assessment, limited variability in radon levels, and insufficient statistical power may have contributed to the observed non-significant associations between radon exposure and child asthma. However, these findings do not rule out a potential association. Future studies employing individual-level radon measurements and larger sample sizes are needed.