Comment: Sorry for any confusion. History may be blamed. Or the dead.

1893. Fluoride known as toxic poison over a century ago. Submitted by Mark Twain, 12/10/2012 - The reply that started this confusing discussion thread.
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In these early years of the industrial revolution came serious air pollution problems. Iron and copper refineries or smelters were the worst culprits. Fumes and fallout from their smokestacks caused obvious injury and sickness to people, livestock, crops, and other vegetation in the surrounding communities and countryside.

Unknown in the early years of the industrial revolution, the most deadly chemical killer in this effluent was hydrogen fluoride (HF), now known to be toxic in a concentration of parts per billion. The term fluorine (F: Periodic Table of Elements, #9), rather than fluoride was then commonly used in referring to the air pollutant. Hydrogen fluoride was itself first identified in industrial emissions after the turn of the century, but its effects had been clearly seen in the areas surrounding these industrial polluters.

Early European Chronology

• 1855. Smelters in Freiburg, Germany first paid damages to neighbors injured by fluorine emissions.
• 1893. The smelters in Freiburg paid out 880,000 marks in damages for fluorine contamination injuries and 644,000 marks for permanent relief.

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