Early life secondhand smoke exposure assessed by hair nicotine biomarker may reduce children's neurodevelopment at 2 years of age ScienceDirect Animal Study Shows Harmful Effects of Secondhand Smoke Even Before Pregnancy Duke Health Secondhand e cigarette aerosols expose kids to less nicotine than cigarettes, study finds, but can still be risky CNN Second hand vaping exposure very low compared to second hand smoking UCL News UCL University College London Does Vaping Cause Secondhand Smoke? The Impact of E Cigarettes and Asthma: What You Need to Know