Secondhand marijuana smoke can cause range of detectable effects, study finds Hub Second hand vaping exposure very low compared to second hand smoking UCL News UCL University College London Just How Harmful Is Vaping? More Evidence Is Emerging. The New York Times Hidden Dangers of Secondhand Vaping Emory Health Digest Can You Fail a Drug Test from Secondhand Smoke? Understanding the Facts Juul study shows secondhand vaping emissions are less toxic than cigarette smoke