As concerns persist over youth vaping, legal attacks on leading e-cigarette company Juul have intensified. Last month, Attorney General Josh Shapiro added Pennsylvania to the growing list of states suing Juul. [...] Proponents of legal action against Juul suggests it’s necessary to hold the e-cigarette makers accountable for what the Food and Drug Administration declared an “epidemic” of teen vaping, with over 5 million teen users in the U.S. But critics worry that resulting restrictions or bans on e-cigarette sales will interfere with Juul use by adults who rely on the product to quit cigarettes, which are worse for health.