Aqua Pura

 is literally "Pure Water" that is available once the DLC pack Broken Steel is installed.

Drinking the water after choosing to infect it with the Modified FEV will result in a player debuff (-2 STR and -1 INT) and, if consumption is repeated, death.

Bugs

 * Giving any amount of Aqua Pura to Water Beggars will result in their death at the next map change, regardless of whether or not the Aqua Pura contains Modified FEV.
 * Sometimes, when changing areas, the message 'Aqua Pura has worn off', as if it was a Chem. However, No stats changes can be seen when Aqua Pura is taken.