Yes, overconsumption of nicotine can lead to temporary side effects like dizziness, headache, nausea, or throat irritation
If you were to write it in regular sentence form it would say "You may not use the PayPal service for activities that...involve the sending, posting, or publication of any messages, content, or materials that, in PayPals sole discretion, are harmful, obscene, harassing, or objectionable..." That should mean the publishing of content would have to be somehow connected to use of the PayPal service (a blog post on a site with a PayPal donation button, for example) rather than shutting down anyone's personal PayPal account because of some random tweet
Each time you smoke, the nicotine levels in your blood vessels get narrower
For sheer hyperbole, few characterizations exceeded Newsweeks cover story at the end of 1995