First of all, people are using herbal like it distinguishes soex from shisha. Tobacco is a plant. Shisha is herbal.
Second of all, soex does not have nicotine, but it does have tar. Any smoke has tar. Tar is defined as the particulate matter in smoke while burning tobacco or other plants.
Just letting you know the only real difference is probably the nicotine and taste. Nicotine is just a stimulant like caffeine.