I heard fluoride is a poison. Is this true?

Yes.

   Fluoride is an acute toxin with a rating higher than that of lead. According to "Clinical Toxicology of Commercial products", 5th Edition, 1984, lead is given a toxicity rating of 3 to 4, and Fluoride is rated at 4 (3 = moderately toxic, 4 = very toxic). On December 7, 1992, the new EPA Maximum Contaminant Level (MCL) for lead was set at 0.015 ppm, with a goal of 0.0ppm. The MCL for fluoride is currently set for 4.0 ppm - that's over 250 times the permissible level of lead.

  The fluoride used in water fluoridation is and always has been a toxic waste product, containing other heavy metals and contaminants.

   Fluorides are cumulative toxins. The fact that fluorides accumulate in the body is the reason that US law requires the Surgeon General to set a Maximum Contaminant Level (MCL) for fluoride content in public water supplies as determined by the EPA. This requirement is specifically aimed at avoiding a condition known as Crippling Skeletal Fluorosis (CSF), a disease thought to progress through three stages. The MCL, designed to prevent only the third and crippling stage of this disease, is set at 4 ppm or 4mg per liter. It is assumed that people will retain half of this amount (2mg), and therefore 4mg per liter is deemed "safe". Yet a daily dose of 2 - 8 mg is known to cause the third crippling stage of CSF.