Fluoride Action Network

Fluoride & Electrocardiogram Abnormalities

By Tara Blank, PhD | July 2012

An electrocardiogram (ECG) is a diagnostic test that measures the electrical activity of the heart. An ECG can reveal heart rate, heart rhythym (i.e. steady or irregular), and the strength and timing of the heart’s natural electrical signals. ECGs are described in terms of “waves” (e.g. amplitude and duration). Problems with the heart can alter electrical activity, and thus altered ECG readings can indicate underlying problems with heart function. ECGs can help diagnose heart attacks, coronary heart disease, irregular or abnormal heartbeat, heart failure, etc.

Studies have observed higher rates of abnormal ECGs among those with skeletal fluorosis compared to normal controls (Ji et al., 2004; Xu and Xu, 1997). Children with dental fluorosis have also been shown to have altered ECGs, including prolonged Q-T interval (Karademir et al., 2011), which is a biomarker for arrhythmias and a risk factor for sudden death. Similar findings have been reported by Okushi (1954) and Takamori (1956). Still another study found an increased incidence of abnormal systolic time interval (STI) in those living in an endemic fluorosis region (Wang et al., 1983).

Altered ECG readings have also been observed in experimental animals with chronic and subacute exposure to fluoride, including sheep (Dönmez and Çinar, 2003), dogs (Kilicalp et al., 2004), goats (Kant et al., 2010), and rabbits (Kumar et al., 2010; Okushi, 1954b).

Excerpts from the Scientific Literature:

“We found statistically significant low T4 levels, hypocalcemia and hyponatremia, increased QT and QTc interval in children with dental fluorosis. Our study shows that decreases in calcium and FT4 levels, increment of sodium levels, due to fluorosis may affect ventricular repolarization. These findings show us that fluorosis makes patients more vulnerable for developing arrhythmias and syncope.”
SOURCE: Karademir S, et al. (2011). Effects of fluorosis on QT dispersion, heart rate variability and echocardiographic parameters in children. Anadolu Kardiyol Derg 11:150-5.

“IVRT [isovolumetric relaxation time] and DT [early filling deceleration time] were significantly higher in fluorosis patients than in controls…MPI [left ventricular myocardial performance index] was significantly higher in fluorosis patients than in controls. We have shown that chronic fluorosis patients had left ventricular diastolic and global dysfunctions.”
SOURCE: Varol E, et al. (2010a). Impact of chronic fluorosis on left ventricular diastolic and global functions. Sci Tot Environ 408:2295-8.

“There was a significant (p<0.001) decrease in the R-R interval (duration between the peaks of two consecutive R waves of ECG) and P-R interval (duration from the starting of P wave to the starting of QRS complex in ECG), while significant (p<0.001) increases in the mean heart rate and corrected QT intervals were observed compared to the initial baseline values. …the present investigation clearly indicates that F interferes with myocardial metabolism…”
SOURCE: Kumar N, et al. (2010). Effects of sodium fluoride on the electrocardiogram of male rabbits. Fluoride 43(2):124-7.

“A significant (p<0.05) increase in P-R, Q-T and S-T intervals were observed in goats of group 1 [fluoride exposed] as compared to their pre treatment values…it may be concluded that subacute toxicity of fluoride produces significant changes in different waves of electrocardiogram…”
SOURCE: Kant V, et al. (2010). Alterations in electrocardiographic parameters after subacute exposure of fluoride and ameliorative action of aluminum sulphate in goats. Biol Trace Elem Res 134:188-94.

“The P-Q interval [time period from initiation of atrial depolarization to initiation of ventricular depolarization; good estimate of AV node function] was significantly (p<0.05) prolonged and sinus bradycardia [lower heart rate] was observed in the sheep with fluorosis…sinusoidal bradycardia in the sheep could be the result of the damage caused by chronic fluoride intoxication on the thyroid gland, the insufficient release of T3 and T4, and the decrease in the PDI [protein-dependent iodine] levels of blood.”
SOURCE: Dönmez N, Çinar A. (2003). Effects of chronic fluorosis on electrocardiogram in sheep. Biol Trace Elem Res 92:115-21.

“…50.73% of patients with skeletal fluorosis had abnormal ECGs, compared with 20% in the control group. A comparison of ECG changes in the two groups shows that skeletal fluorosis patients exhibit signs of myocardial damage which seriously interferes with cardiac function. Our study shows that the severity of skeletal fluorosis is directly related to the severity of abnormal cardiac function, as demonstrated by the electrocardiograms. The results show that fluoride in drinking water consumed over time is harmful not only to bones and teeth but also to the cardiovascular system…”
SOURCE: Xu RY, Xu, RQ. (1997). Electrocardiogram analysis of patients with skeletal fluorosis. Fluoride 30(1):16-8.

“A functional study of the blood circulation system in vibration disease patients in fluorite mines revealed changes in the cerebral hemodynamics with more pronounced angiotenic reactions…From the ECG data we found a higher incidence of dystrophic changes in the myocardium, arterial hypertension and disturbance of the regulation of the cardiovascular system…”
SOURCE: Tartatovskaya LY, et al. (1995). Clinico-hygiene assessment of the combined effect on the body of vibration and fluorine. Noise and Vibration Bulletin (from: Meditsina Truda i Promyshlennaya Ekologiya 10:8-10).

 “[The incidence of abnormal STI [systolic time interval] in severe endemic fluorosis region was increased (p<0.025)…patients with endemic fluorosis might have their heart injured and resulted in decrease of myocardiac systolic function which could make signs of subclinic cardiac dysfunction.]”
SOURCE: Wang Y, et al. (1983). A comparative study on systolic time interval of populations in mild and severe endemic fluorosis regions. Chin J Endem 7(1):60 (Abstract).

“Our studies indicate a higher incidence of myocardial damage in the high-fluoride districts [0.6 to 4.4 ppm]. Our results further indicate that the majority of residents with myocardial damage also have mottled teeth [dental fluorosis]. Conversely, among those without mottled teeth, the negative EKG findings outnumber those with myocardial damage.”
SOURCE: Takamori T, et al. (1956). Electrocardiographic studies of the inhabitants in high fluoride districts. Fluoride 4(4):204-9.

“In the electrocardiogram of rabbits given sodium fluoride orally, a pattern of myocardial damage was observed, namely depressed ST, inverted T, prolonged QT interval, multifocal ventricular premature contraction, bundle branch block, and pulmonary P.”
SOURCE: Okushi I. (1954b). Changes in the heart muscle due to chronic fluorosis. Part II: Experimental studies on the effects of sodium fluoride upon the heart muscle of rabbits. (Abstracted from) Shikoku Acta Medica 5:238-45.