Key Findings - Estimated Minimum Lethal Dose of Fluoride:

1) The currently accepted estimate for the minimum lethal dose of fluoride is 5 mg/kg (i.e. 5 milligrams of fluoride for each kilogram of bodyweight). This dose is referred to in the medical literature as the "Probably Toxic Dose" or "PTD." It is sufficient to produce severe poisoning, including death, in some individuals.

2) All fluoride toothpastes sold in the United States, including flavored toothpastes specifically marketed to children, contain the minimum lethal dose of fluoride.

3) Each year there are thousands of reports to Poison Control centers in the United States related to excessive ingestion of fluoride dental products (toothpaste, mouthrinses, and supplements).

4) Early symptoms of acute fluoride toxicity (e.g. gastrointestinal pain, nausea, vomiting, excess salivation, fever) can be produced at doses well below 5 mg/kg - at doses as low as 0.1 to 0.3 mg/kg. These symptoms are responsible for many of the calls to Poison Control.

NOTE: For a list of toothpastes that do not contain fluoride, click here

Minimum Dose of Fluoride that can Kill - "The Probably Toxic Dose":

The "Probably Toxic Dose" (PTD) for fluoride is 5 mg/kg:

"The PTD, 5.0 mg F/kg, is defined as the dose of ingested fluoride that should trigger immediate therapeutic intervention and hospitalization because of the likelihood of serious toxic consequences.”
SOURCE: Whitford GM. (1987). Fluoride in dental products: safety considerations. Journal of Dental Research 66: 1056-60.

"The (PTD) would be the minimum dose that could cause toxic signs and symptoms, including death, and that should trigger immediate therapeutic intervention and hospitalization."
SOURCE: Whitford GM. (1987). Fluoride in dental products: safety considerations. Journal of Dental Research 66: 1056-60.

“Based on these reports, it is concluded that the PTD is approximately 5 mg F/kg. This does not imply that this dose must result in death nor that a somewhat smaller dose would be innocuous. It does mean that even if it is only suspected that 5 mg F/kg has been ingested, it should be assumed that an emergency exists and that immediate treatment and hospitalization are required.” (italics in original)
SOURCE: Whitford GM. (1990). The physiological and toxicological characteristics of fluoride. Journal of Dental Research 69(Spec Issue):539-49.

"it may be concluded that if a child ingests a fluoride dose in excess of 15 mg F/kg, then death is likely to occur. A dose as low as 5 mg F/kg may be fatal for some children. Therefore, the probably toxic dose (PTD), defined as the threshold dose that could cause serious or life-threatening systemic signs and symptoms and that should trigger immediate emergency treatment and hospitalization, is 5 mg F/kg."
SOURCE: Whitford G. (1996). Fluoride Toxicology and Health Effects. In: Fejerskov O, Ekstrand J, Burt B, Eds. Fluoride in Dentistry, 2nd Edition. Munksgaard, Denmark. p 171.

"This does not mean that doses lower than 5.0 mg F/kg should be regarded as innocuous." (italics in original)
SOURCE: Whitford GM. (1987). Fluoride in dental products: safety considerations. Journal of Dental Research 66: 1056-60.

Excerpts from the Scientific Literature - Minimum Lethal Dose in Dental Products: (back to top)

“The concentrations and quantities of fluoride in selected dental products are discussed in relation to the PTD. It is concluded that, as these products are currently packaged, most of them contain quantities of fluoride sufficient to exceed the PTD for young children."
SOURCE: Whitford GM. (1987). Fluoride in dental products: safety considerations. Journal of Dental Research 66: 1056-60.

Minimum Lethal Dose in Dental Products - Fluoridated Toothpaste: (back to top)

"WARNING: Keep out of reach of children under 6 years of age. If you accidentally swallow more than used for brushing, seek professional help or contact a poison control center immediately."
SOURCE: FDA Mandated Warning on Fluoride Toothpaste Labels Sold in U.S.

"One death from ingestion of fluoride toothpaste was reported to the American Association of Poison Control Centers in 2002."
SOURCE: Nochimson G. (2004). Toxicity, Fluoride. eMedicine.com.

Minimum Lethal Dose of Fluoride Contained in One Tube of "Colgate for Kids" Toothpaste
Age of Child	Average Weight*	Dose of fluoride which could kill child	Percent of "Colgate for Kids" toothpaste which, if swallowed, could kill child**
2 years	~12 kg	60 mg	42% of tube
3 years	~15 kg	75 mg	53% of tube
4 years	~16 kg	80 mg	56% of tube
5 years	~ 18 kg	90 mg	63% of tube
6 years	~20 kg	100 mg	70% of tube
7 years	~22 kg	110 mg	77% of tube
8 years	~25 kg	125 mg	87% of tube
9 years	~28 kg	140 mg	98% of tube
*Average weight data obtained here ** The fluoride concentration in Colgate for Kids toothpaste is 1,100 ppm. At 130 grams of paste in the average tube, this equals 143 milligrams of fluoride.

Minimum Lethal Dose in Dental Products - Fluoride Supplements/Vitamins: (back to top)

Number of Ingested Tablets that Could Kill: Fluoride Supplements/Vitamins
Age of Child	Average Weight*	No. of 1 mg/F Tablets**
2 years	~12 kg	60 tablets
3 years	~15 kg	75 tablets
4 years	~16 kg	80 tablets
5 years	~ 18 kg	90 tablets
*Average weight data obtained here ** 1 mg fluoride tablets typically come in containers with either 30 or 90 tablets.

U.S. Poison Control Center Reports - Fluoridated Dental Products: (back to top)

Reports to the American Association of Poison Control Centers Related to Fluoride-containing Dental Products and the Outcomes, 1989-1994 (Data from: Shulman 1997)
			# Treated in Health Care Facilities	Medical Outcome*
Year	Product	# Reports		None	Minor	Moderate	Major	Death
1989	Toothpaste	1,392	101	464	371	15	0	0
	Mouthrinse	1,185	56	503	115	3	0	0
	Supplements	4,028	375	1,807	663	14	1	1
	Vitamins**	3,153	184	1,214	135	0	0	0
1990	Toothpaste	1,379	107	468	329	7	0	0
	Mouthrinse	1,299	64	511	109	2	0	0
	Supplements	4,437	338	1,950	653	10	0	0
	Vitamins**	2,938	135	949	0	0	0	0
1991	Toothpaste	1,623	120	497	403	15	0	0
	Mouthrinse	1,418	72	556	112	0	0	0
	Supplements	4,350	368	1,593	667	12	0	0
	Vitamins**	2,741	102	595	93	3	0	0
1992	Toothpaste	2,331	141	700	497	17	1	0
	Mouthrinse	1,338	52	545	92	1	0	0
	Supplements	4,171	340	1,579	624	12	0	0
	Vitamins**	2,949	122	883	111	1	0	0
1993	Toothpaste	2,507	143	725	571	21	0	0
	Mouthrinse	1,144	52	409	75	4	0	0
	Supplements	3,483	249	1,143	503	16	0	1
	Vitamins**	2,650	105	706	100	0	0	0
1994	Toothpaste	3,369	166	852	800	19	1	0
	Mouthrinse	1,220	40	409	79	3	0	0
	Supplements	3,544	240	1,224	489	22	1	0
	Vitamins**	2,493	86	663	111	0	0	0
* No effect: No signs or symptoms as the result of exposure. Minor effect: Minimally bothersome signs or symptoms that generally resolved without residual disability or disfigurement (e.g. self-limiting gastrointestinal symptoms). Moderate effect: More pronounced or prolonged signs or symptoms, or more of a systemic nature than minor systems. While the symptoms are not life-threatening (e.g., disorientation or high fever that responds readily to treatment), some form of treatment is indicated. Major effect: Signs and symptoms that are life-threatening or result in significant residual disability or disfigurement. ** With fluoride but without iron.
SOURCE: Shulman JD, Wells LM. (1997). Acute fluoride toxicity from ingesting home-use dental products in children, birth to 6 years of age. Journal of Public Health Dentistry 57: 150-8.

Excerpts from the Scientific Literature - Advanced Symptoms of Acute Fluoride Poisoning: (back to top)

NOTE: For information on the early symptoms of acute fluoride poisoning, click here

"At higher doses, the patient becomes acidotic, comatose, convulsive and may experience cardiac arrythmias. Death may follow with cardiac failure or respiratory paralysis."
SOURCE: Rubenstein LK, Avent MA. (1987). Frequency of undesirable side-effects following professionally applied topical fluoride. Journal of Dentistry for Children 54: 245-247.

"When sufficiently large amounts of fluoride are ingested as a single dose, a catastrophic chain of events rapidly develops. The first effects experienced by the victim usually include nausea, vomiting, and burnining or cramp-like abdominal pains. There may be excessive salivation and tearing, mucous discharges from the nose and mouth, a generalized weakness, paralysis of the muscles of swallowing, carpo-pedal spasms or spasm of the extremities, tetany, and generalized convulsions. The pulse may be thready or not detectable. Blood pressure often falls to dangerously low levels at some point during the course of the toxic episode. As respiration is depressed, a respiratory acidosis develops. Plasma potassium levels are elevated, indicating a generalized toxic effect on cell membrane function. Cardiac arrhythmias may develop in association with the hyperkalemia. Plasma calcium levels are typically depressed, sometimes to extraordinarily low values (5 mg% or less). Extreme disorientation or coma usually precedes death, which often occurs within the first few hours after the fluoride dose."
SOURCE: Whitford GM. (1987). Fluoride in dental products: safety considerations. Journal of Dental Research 66: 1056-60.

"Headaches, paresthesias, visual disturbances, optic neuritis, convulsions and central nervous system depression may result from the direct effect of fluoride ion on nervous tissue."
SOURCE: Ellenhorn MJ, Barceloux DG. (1988). Medical Toxicology: Diagnosis and Treatment of Human Poisoning. Elsevier; New York. pp. 534.

"After a large dose of a soluble fluoride is ingested, accidentally or by suicidal intent, there follows a catastrophic symptom train. The course of poisoning is violent and brief; deaths are frequently recorded in 2-4 hours. A 'large' dose means a teaspoonful or more (5-10 gm) of sodium fluoride. The exact cause of death is still obscure.

The accidental ingestion of sodium fluoride at Oregon State Hospital, described by Lidbeck et al. (1943) produced the highest morbidity and mortality ever reported in a single episode. Following an evening meal of scrambled eggs, there were 263 cases of acute poisoning; 47 terminated fatally. When toxicologic examination revealed the presence of sodium fluoride, it was apparent that roach powder had been placed in the scrambled eggs served at the evening meal. Subsequent investigation disclosed that a patient had unwittingly mistaken roach powder for powdered milk and had added approximately 17 pounds of the compound to a 10-gallon mixture of scrambled eggs. Fortunately the eggs were not generally distributed throughout the hospital but were served to only five of the working wards.

The food was rejected by many of the patients because of a salty or soapy taste, while others complained of numbness of the mouth. Extremely severe nausea, vomiting and diarrhea occurred abruptly and at times simultaneously, and blood was noted in the vomitus and stools in many instances. Soon after the meal there were complaints of abdominal burning and cramplike pains. General collapse developed in most instances but at variable periods of time, apparently depending on the concentration of the poison. This was characterized by pallor, weakness, absent or thready pulse, shallow unlabored respiration, weak heart tones, wet cold skin, cyanosis and equally dilated pupils. When this picture was pronounced, death almost invariably occurred. Local or generalized urticaria occurred in some instances, while in others there was a thick mucoid discharge from the mouth and nose. When death was delayed, and in some cases in which recovery occurred, there were paralysis of the muscles of deglutition, carpopedal spasm and spasm of the extremities. Convulsions and abdominal tenderness and rigidity were absent. In the majority of cases, death occurred between two and four hours after ingestion of the food, although in a few instances death was delayed for eighteen or twenty hours."
SOURCE: Hodge HC, Smith FA. (1965). Fluorine Chemistry. Volume 4. Academic Press, New York.

Examples - Severe Acute Fluoride Poisoning: (back to top)

Fluoride Causes a Close Call for an Area Child - KAALtv.com May 18, 2004

$750,000 Given in Child's Death in Fluoride Case - New York Times January 20, 1979

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