You don't need to look for anything. What I get from the article is that it was carrying a concentrated HCl (Hydrochloric Acid) which can release gasses and cause some damage to soft tissue of the body. (One of the more acidic acids, and in high concentrations can be quite dangerous.) HCl is a component of your stomach acid, along with Potassium Chloride and Sodium Chloride. Also, it looks as if the roads were wet which would have diluted the chemical when it mixed with water. (The article falsely states that HCl releases a gas when it comes in contact with water, this if very very false...HCl is a mixture of Hydrogen Chloride in solution with H2O, concentrated HCl becomes diluted HCl when it comes in contact with water...which is actually very good.) If you don't have any signs of burns at this point, you will be fine.

Fumes were the main issue, but it doesn't seem like you should be worried. You're still breathing so you're probably fine.

Edit: I would like to add that this looks a lot like a case of "small town making a big deal out of something almost exciting..."