- Exposure to magnetic field (MF) nonionizing radiation during pregnancy was associated with increased risk for ADHD in offspring in this cohort study.
Why this matters
- The rates of ADHD have been increasing over the past decades, and research continues into potential environmental factors.
- 61/1454 children were diagnosed with ADHD.
- Those whose mothers had MF exposure above the cutoff during pregnancy had a higher risk for ADHD: adjusted HR, 2.01 (95% CI, 1.06-3.81).
- Those who also had asthma or atopic dermatitis and whose mothers had exposure above the cutoff had the highest risk for ADHD: adjusted HR, 4.57 (95% CI, 1.61-12.99).
- Longitudinal birth cohort study.
- Cohort obtained from 2 birth cohorts from Kaiser Permanente Northern California: pregnancies during October 1, 1996 to October 31, 1998, and from May 1, 2006 to February 29, 2012.
- Pregnant participants wore a meter to capture the level of MF nonionizing radiation during a 24-hour period.
- Exposure classified as low with 1.3 mG of exposure and high with ≥1.3 mG.
- Mother-child dyads (n=1454) were followed up to 20 years.
- Interviews were used to identify potential confounders.
- Funding: National Institute of Environmental Health Sciences; California Public Health Foundation.
- Measurement taken during a single 24-hour period.
- Binary classification of exposure, not continuous.
- No causation established.