The bottle was kept in the engine room workshop by third-party contractors. After drinking, ETO realized that it was thinners and immediately spat out most of the contents.
He then drank salt water to induce vomiting in order to get any thinner out of his body. The company doctor advised him to consume plenty of fluids, eat light food and rest for a few days.
The investigation showed that the third-party contractors working onboard had temporarily stored thinner in the mineral water bottle. The third-party contractors were not briefed enough and behaved in an unsafe way.
Crew and third-party contractors were called to only store chemicals in proper, appropriately marked containers. Crew were recommended to not drink water from shared bottles in common places, and carry their own bottle.