During a press conference, Pinellas County Sheriff Bob Gualtieri said that a legitimate operator saw the change and quickly reversed it, but signaled that the hacking attempt was a serious threat to the city's water supply. Sodium hydroxide is also known as lye and can be deadly if ingested in large amounts.

"The hacker changed the sodium hydroxide from about one hundred parts per million, to 11,100 parts per million," Gualtieri said, adding that these were "dangerous" levels. When asked if this should be considered an attempt at bioterrorism, Gualtieri said, "What it is is someone hacked into the system not just once but twice ... opened the program and changed the levels from 100 to 11,100 parts per million with a caustic substance. So, you label it however you want, those are the facts."

In smaller quantities, sodium hydroxide can cause severe skin burns and eye damage. Small amounts of sodium hydroxide are put in some cities' drinking water supplies to prevent corrosion to pipes and to bring the pH up (it is a strong base). The news highlights what could be a serious cyber and physical security breach, and raises questions about how secure access to such a sensitive system really was.