Accidents happen

The hexafluorosilicic acid used to fluoridate drinking water has corrosivity potential of hydrofluoric acid which is the most corrosive and one of the most toxic substances known. The hexafluorosilicic acid cannot be stored in glass or unlined metal containers, it is so corrosive. (See:, also see

The hexafluorosilicic acid is shipped to the water treatment plants in specially lined tanks, containing 4,000 – 5,000 gallons. The shipments are carried by lorries along busy motorways, through densely populated areas and small villages throughout England.

Since the government plans to fluoridate most of the UK, these shipments will become much more common, thus the odds of an accident are substantially increased. (see Environmental Risk).

If there were to be a motorway accident involving a hexafluorosilicic acid spill, most hospitals and emergency crews (firemen) may not know what to do, or be ill prepared to cope with the situation. For instance, if the wrong chemicals were used to neutralise the acid, the consequences could be devastating in a densely populated area or busy motorway.

If a major roadway accident happened in a small village, much of the village would have to be razed and carried off to a hazardous waste landfill, and the top two feet of soil around the spill would also have to be carted off to a hazardous waste landfill. There is also the potential of well water contamination. If it is raining, then they have an environmental mess on their hands.

The most insidious characteristic of hexafluorosilicic acid is that if someone has skin contact, it does not react immediately, it takes from two to twenty-four hours for a person to feel any symptoms. By that time, they may well be on their way to acute hypocalcemia, hypomagnesemia, and hyperkalemia, then subsequent cardiac arrest with acute exposures. The fluoride will rob serum of calcium, potassium and magnesium that are essential for cardiac function. Calcium is also essential for neurological function. Even with proper medical intervention, people who receive acute exposures to soluble fluorosilicate salts, or hexafluorosilicic acid fumes can often suffer long-term adverse health effects.

When the acid comes in contact with tarmac, etc., the volatile reaction creates highly toxic and corrosive hydrogen fluoride gas. The vapours emitted from the reaction can affect people several miles away from the actual spill – the vapours will also etch glass, so you can imagine what they can do to the throat, mucus membranes and lungs. The airborne hydrogen fluoride will not only burn the skin, but it will be absorbed into the body also, causing fluoride poisoning.

The corrosiveness and toxicity of chlorine and the other water treatment chemicals are not in the same league with hexafluorosilicic acid. Hexafluorosilicic acid is in a class unto itself when it comes to toxicity, corrosivity and the damage it can do to the environment and a person’s health.

You should ask the water companies if they have a specific emergency plan in case of overfeed or major spill – the same applies to the government, fire services and the health authorities (who are promoting the use of this dangerous chemical). You should demand to see a hard copy of the emergency plans. Chances are that the health authorities, goverment and water companies haven’t thought about the potential of an accident and have no emergency plan whatsoever. The fire services are probably ill-equipped to deal with the situation.

More than likely, hospital casualty centres do not know the basic emergency measures for fluoride poisoning, much less being able to cope with a large scale incident. Ends.

See the excerpts form articles about a 1994 accident below



  • Early today, the highway remained closed in both directions, though officials were hopeful it would open by the morning rush hour. About 2,300 people remained in shelters, evacuated from their homes.
  • Authorities were frustrated in attempts to neutralize the acid with lime and potash, which delayed I-4’s reopening. Fumes also were detected late Tuesday in the neighborhood of Deltona Woods, causing emergency workers to conduct a midnight door-to-door evacuation.
  • Fluorosilicic is a highly corrosive acid used in the process of adding fluoride to drinking water, hazardous waste experts said.
  • If inhaled, it can cause respiratory difficulty, burning eyes and numbness around the lips. Upon contact with skin, it creates a burning and tingling sensation. Symptoms can take up to 24 hours to appear, medical experts said.
  • The chemical evaporates quickly and is carried by the wind. Fearing a health hazard, police began evacuating homes within a mile area, including about 1,750 people in Orange City and 500 people in Deltona. Students and teachers at Deltona High School went home early.


SPILL CLEANUP PRESSED ON I-4; [CENTRAL FLORIDA Edition] Orlando Sentinel. Orlando, Fla.: Sep 9, 1994. pg. C.3

  • A tanker truck spilled about 4,500 gallons of fluorosilicic acid on I-4 on Tuesday, prompting officials to evacuate residents and close a two-mile stretch of the highway between Deltona and Orange City.
  • Officials of Florida Spill Response, a Cocoa-based company, say they expect to have the spill cleaned up by Saturday. The eastbound outside lane closed at 7 p.m. Thursday and will remain closed indefinitely, state DOT spokesman Steve Homan said.
  • Michael Taylor, the on-scene coordinator for the EPA , said the agency wants the cleanup to continue nonstop until the contaminated soil has been removed.
  • Experts do not know whether the groundwater has been contaminated. “At any site you go to, it’s always a danger,” Taylor said, “especially with bad weather.” It rained most of Thursday.
  • As a precaution, the Public Health Department has advised owners of private wells in the area to have their water tested for traces of the chemical before drinking it.
  • Robert Pierce, vice president of Florida Spill Response, said he has a geologist testing the area to determine whether acid has seeped into the water table or the aquifer.
  • Car washes will remain open through this evening. Those wanting cars decontaminated must make appointments by calling: (904) 822-6422, 822-6423 or 822-6424.


10, 1994. pg. D.1

  • “The only thing we could do was assume the worst,” Rogers said. “When you get into hazardous materials you don’t play games.”
  • The chemical the truck was toting is used in fluoridating water, etching glass and other processes. It is destructive to human tissue, causes breathing difficulties and reacts with metal, said Michael Taylor of the U.S. Department of Environmental Protection.
  • Because hazardous materials experts were unable to immediately identify the chemical, they did not know how to neutralize it.
  • The highly volatile acid crystalized within an hour after contact with the air, Rogers said. That made it more difficult to neutralize. Once emergency workers identified the acid, they were able to put a one-inch layer of lime on it, cover that with potash and slowly pour water onto it, simultaneously liquifying and neutralizing it.
  • Pencco Inc. is paying for the cleanup, including the decontamination of more than 100 cars.
  • More than 300 tons of contaminated dirt are being hauled from the sides of I-4. One eastbound lane of the highway has been closed since Thursday, when the EPA ordered that work be continued at all hours. It could remain closed through Sunday, said Pete Fonrouge, senior project manager for Florida Spill Response Corp., the company handling the cleanup.
  • Geologists and EPA representatives will be testing groundwater for contamination. Residents near the spill have been advised not to drink well water until it has been tested for traces of the chemical.
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