the addictive substance in tobacco is Addiction Guide: Symptoms, Risks & Recovery All About Nicotine Addiction -

AJ's is a different matter

Square Mile Coffee Roasters / Youtuber / Author / (sorry, but no recommendations via @ or DM) London Joined January 2009

In a collection of scientific papers in the journal Addiction, researchers said that while standardised packs were still too new to provide substantial evidence, studies so far showed they were likely to reduce smoking rates

31 forum said the adolescent brain is vulnerable to the rewarding effects of nicotine, especially aspects of their cognitive, emotional, social, sensory, and motor development, which could pave the way for the use of other drugs and substances

Here are the two I get asked most often