An endocrine gland that accumulates high levels of fluoride

According to the US EPA ,

The endocrine system consists of a set of glands and the hormones they produce that help guide the development, growth, reproduction, and behavior of animals including human beings. Some of the endocrine glands include the pituitary, thyroid, and adrenal glands, the female ovaries and male testes. Hormones are chemicals, produced by endocrine glands, that travel through the bloodstream and cause responses in other parts of the body. Examples of hormones include adrenaline, which helps stimulate physical activity, and estrogen, which is essential for female reproductive function. Hormones can produce both positive and negative effects. For example, some types of breast cancer are exacerbated by estrogen, but studies also indicate that estrogen has a protective effect in combating heart disease and osteoporosis-related fractures.

Chemicals that interfere with the normal functioning of this complex system are known as "endocrine disruptors." Disruption of the endocrine system can occur in various ways.

For example, some chemicals may mimic a natural hormone, fooling the body into over-responding to the hormone. Other chemicals may block the effects of a hormone in parts of the body normally sensitive to it. Still others may directly stimulate or inhibit the endocrine system, leading, to overproduction or underproduction of hormones. Certain drugs are used to intentionally cause some of these effects, such as birth control pills. (For more information: see EPA's: Endocrine Disruptor Screening Program.)

In July 1991 a multi-disciplinary group of experts researching endocrine disruption reached consensus and published the "The Wingspread Conference Statement." This statement sent shockwaves through the international scientific and regulatory communities. The scientists stated that the "cancer paradigm is insufficient" when assessing chemicals. That certain "chemicals can cause severe health effects other than cancer" that are of "a profound and insidious nature." The scientists stated:

We are certain of the following:

• A large number of man-made chemicals that have been released into the environment, as well as a few natural ones, have the potential to disrupt the endocrine system of animals, including humans. Among these are the perisisten, bioaccumulative, organohalogen compounds that include some pesticides (fungicides, herbicides, and insecticides) and industrial chemicals, other synthetic producs, and some metals.

• Many wildlife populations are already affected by these compounds. The impacts include thyroid dysfunction in birds and fish; decreased fertility in birds, fish, shellfish, and mammals; decreased hatching success in birds, fish, and turtles; gross birth deformities in birds, fish and turtles; metabolic abnormalities in birds, fish, and mammals; behavioral abnormalities in birds; demasculinization and feminization of male fish, birds and mammals; defeminization and masculinization of female fish and birds; and compromised immune systems in birds and mammals.

• The patterns of effects vary among species and among compounds. Four general points can nonetheless be made:
(1) the chemicals of concern may have entirely different effects on the embryo, fetus, or perinatal organism than on the adult;
(2) the effects are most often manifested in offspring, not in the exposed parent;
(3) the timing of exposure in the developing organism is crucial in determining its character and future potential; and
(4) although critical exposure occurs during embryonic development, obvious manifestations may not occur until maturity.

• Laboratory studies corroborate the abnormal sexual development observed in the field and provide biological mechanisms to explain the observation in wildlife.

• Humans have been affected by compounds of this nature too. The effects of DES (diethylstilbestrol), a synthetic therapeutic agent, like many of the compounds mentioned above, are estrogenic. Daughters born to mothers who took DES now suffer increased rates of vaginal clear cell adenocarcinoma, various genital tract abnormalities, abnormal pregnancies, and some changes in immune responses. Both sons and daughters exposed in utero experience conge4nital anomalies of their reproductive system and reduced fertility. The effects seen in utero DES-exposed humans parallel those found in contaminated wildlife and laboratory animals, suggesting that humans may be at risk to the same environmental hazards as wildlife.

The profound concern generated from this 1991 statement led to an international effort to identify chemicals that disrupt hormonal systems (see OECD, Europa). What the public learned in 1991 was that no chemical had been tested for its hormonal disrupting potential. The regulatory communities committed to test every chemical in use (more than 65,000). In order to achieve this goal, several years were spent on developing the protocols for testing and prioritizing chemicals for these tests.

Since 1996, endocrine disruptors have been consigned the highest priority for research, testing, and regulation at the US EPA. Unfortunately, the major focus is mainly limited to effects associated with estrogen, androgen, and thyroid hormones. Theoretically, all endocrine glands are considered exquisitely important. However, the pineal gland is not on the radar screen due to the lack of understanding of the role of the human pineal. Because of this, there is an enormous effort underway, by the international scientific community, to obtain this knowledge. The FAN Pesticide Project has been collecting abstracts on this research - see

Abstracts on the Pineal Gland by Year

EPA developed the Endocrine Disruptor Screening Program (EDSP)

in response to a Congressional mandate in the Federal Food, Drug, and Cosmetic Act (FFDCA) "to determine whether certain substances may have an effect in humans that is similar to an effect produced by a naturally occurring estrogen, or such other effects as [EPA] may designate" (21 U.S.C. 346a(p)). When carrying out the program, the statute requires EPA to "provide for the testing of all pesticide chemicals." The statute also provides EPA with discretionary authority to "provide for the testing of any other substance that may have an effect that is cumulative to an effect of a pesticide chemical if the Administrator determines that a substantial population may be exposed to such a substance." In addition, section 1457 of the Safe Drinking Water Act provides EPA with discretionary authority to provide for testing, under the FFDCA 408(p) screening program, "of any other substances that may be found in sources of drinking water if the Administrator determines that a substantial population may be exposed to such substance." (Ref: EPA's EDSP site)

See ERICE consensus statement on endocrine disrupting chemicals and their effect on the brain and behaviour:

We are certain of the following:
Endocrine-disrupting chemicals can undermine neurological and behavioral development and subsequent potential of individuals exposed in the womb or, in fish, amphibians, reptiles, and birds, the egg. This loss of potential in humans and wildlife is expressed as behavioral and physical abnormalities. It may be expressed as reduced intellectual capacity and social adaptability, as impaired responsiveness to environmental demands, or in a variety of other functional guises. Widespread loss of this nature can change the character of human societies or destabilize wildlife populations...

The following presents information on the pineal gland. The information is compelling and relevant to the concern of the bioaccumulation of fluoride in the human body.

In mammals, the pineal gland is located above the thalamus of the brain between the cerebral cortices. In the 1990s, Jennifer Luke of the UK discovered that the pineal gland is a major site of fluoride accumulation within the body - with higher concentrations of fluoride than either teeth or bone.

Luke's studies indicate that the accumulation of fluoride in the pineal gland can reduce the gland's synthesis of melatonin, a hormone that helps regulate the onset of puberty. Fluoride-treated animals were found to have reduced levels of circulating melatonin and an earlier onset puberty than untreated animals. Luke concluded:

"The safety of the use of fluorides ultimately rests on the assumption that the developing enamel organ is most sensitive to the toxic effects of fluoride. The results from this study suggest that the pinealocytes may be as susceptible to fluoride as the developing enamel organ"

Ref: The Effect of Fluoride on the Physiology of the Pineal Gland. Jennifer Anne Luke, 1997. A dissertation submitted to the School of Biological Sciences, University of Surrey, in fulfillment of the requirements for the Degree of Doctor of Philosophy.
See excerpts

The fact that fluoride's impact on the pineal gland was never studied, or even considered, before the 1990s, highlights a major gap in knowledge underpinning current policies on fluoride and health.

The Endocrine System:

Illustration by K. Born in Our Stolen Future (1996)
by Theo Colborn, Dianne Dumanoski and JP Myers

The Pineal Gland: A Photoperiodic Transducer
Through its nocturnal secretion of the biogenic amine melatonin, the pineal has effects on the regulation of many internal physiological rhythms and may provide an important clue for translating photoperiodic stimuli into action. Furthermore, melatonin can alter coat pigmentation and hair growth; can inhibit hypothalamic regulation of the HPA [Hypothalamic-pituitary-adrenal], HPT [Hypothalamic-pituitary-thyroid], and HPG [Hypothalamic-pituitary-gonadal] axes; and has been shown to enhance the immune response system (Norris, 1999). Photic input in birds and mammals is accomplished primarily via the optic visual system. However, the pineal of most fishes, amphibians, and reptiles also plays an important role as a direct photoreceptor, and through secretion of melatonin, it may be an important modulator of the HPA, HPT, and HPG axes as well. Any environmental factor that alters pineal function may have profound effects on the well-being of vertebrates.
Chapter 3: Endocrinology and Endocrine Toxicology
From the report: 2002. Safety Global Assessment of the State-of-the Science of Endocrine Disruptors. International Programme on Chemical Safety. WHO/PCS/EDC/02.2 - An assessment prepared by an expert group on behalf of the World Health Organization, the International Labour Organisation, and the United Nations Environment Programme. Edited by: Terri Damstra, Sue Barlow, Aake Bergman, Robert Kavlock, Glen Van Der Kraak.

Until Jennifer Luke's work (1,2) many people were unaware that the pineal gland produced the same crystals of calcium hydroxyapatite as the bones and teeth. [Having looked through numerous text books I found that these crystals are called "brain sand" -- a term used by scientists, not Hollywood producers! The terminology may have been factor.] According to Luke's 1997 thesis (1):

"It is remarkable that the pineal gland has never been analysed separately for F because it has several features which suggest that it could accumuate F. It has the highest calcium concentration of any normal soft tissue in the body because it calcifies physiologically in the from of hydroxyapatite (HA). It has a high metabolic activitity coupled with a very profuse blood supply: two factors favouring the deposition of F in mineralizing tissues. The fact that the pineal is outside the blood-brain barrier suggests that pineal HA could sequester F from the bloodstreatm if it has the same strong affinity for F as HA in the other mineralizing tissues (page 1).

"After a half a century of the prophylactic use of fluorides in dentistry, we now know that fluoride readily accumulates in the human pineal gland. In fact, the aged pineal contains more fluoride than any other normal soft tissue... However, the pineal gland is unique in that it can be classified as a soft or as a mineralizing tissue. In terms of mineralized tissue, the mean fluoride concentration in the pineal calcification was equivalent to that in severely fluorosed bone and more than four times higher than in corresponding bone ash, i.e., 8,900 ± 7,700 vs. 2,040 ± 1,100 mg/kg, respectively. The calcification in two of the 11 pineals analysed in this study contained extremely high levels of fluoride: 21,800 and 20,500 mg/kg (page 167)."

Luke's work is particularly illuminating because she showed that fluoride accumulated in the human pineal gland. She also found that fluoride lowered the production of melatonin in animal studies - the hormone produced by the pineal gland.

Luke analyzed the pineal glands of 11 elderly corpses in the UK and found that the levels of fluoride were extremely high (a mean of about 9,000 ppm).

Luke also noted a finding from the first 10-year follow-up health study of the Newburgh-Kingston fluoridation trial (which was not thought significant at the time) that on average the girls in Newburgh started menstruation 5 months earlier than the girls in the control, non-fluoridated, city of Kingston (3). -- see excerpts below.

One of the risks we may be taking by exposing our whole population to fluoride is interfering with delicate regulatory timing processes, from the onset of puberty to the aging process. - EC.

1. Luke J (1997). The effect of fluoride on the physiology of the pineal gland. Ph.D. Thesis. University of Surrey, Guildord, UK --see 1997 abstract below.

2. Luke J (2001). Fluoride deposition in the aged human pineal gland. Caries Res. 35:125-128.

3. Schlesinger ER, Overton DE, Chase HC, Cantwell KT (1956). Newburgh-Kingston caries-fluorine study X111. Pediatric findings after ten years. J Amer Dent Assoc 52: 296-306.

Adverse Effects - Sodium fluoride - CAS No. 7681-49-4
Caries Res 2001 Mar-Apr;35(2):125-8

Fluoride deposition in the aged human pineal gland.

Luke J.

School of Biological Sciences, University of Surrey, Guildford, UK.

The purpose was to discover whether fluoride (F) accumulates in the aged human pineal gland. The aims were to determine (a) F-concentrations of the pineal gland (wet), corresponding muscle (wet) and bone (ash); (b) calcium-concentration of the pineal. Pineal, muscle and bone were dissected from 11 aged cadavers and assayed for F using the HMDS-facilitated diffusion, F-ion-specific electrode method. Pineal calcium was determined using atomic absorption spectroscopy. Pineal and muscle contained 297+/-257 and 0.5+/-0.4 mg F/kg wet weight, respectively; bone contained 2,037+/-1,095 mg F/kg ash weight. The pineal contained 16,000+/-11,070 mg Ca/kg wet weight. There was a positive correlation between pineal F and pineal Ca (r = 0.73, p<0.02) but no correlation between pineal F and bone F. By old age, the pineal gland has readily accumulated F and its F/Ca ratio is higher than bone.

PMID: 11275672 [PubMed - indexed for MEDLINE]

1997. A dissertation submitted to the School of Biological Sciences, University of Surrey, in fulfilment of the requirements for the Degree of Doctor of Philosophy. Guildford 1997.
The effect of fluoride on the physiology of the pinal gland
Jennifer Anne Luke
Abstract: The purpose was to discover whether fluoride (F) accumulates in the pineal gland and thereby affects pineal physiology during early development. The [F] of 11 aged human pineals and corresponding muscle were determined using the F-electrode following HMDS/acid diffusion. The mean [F] of pineal was significantly higher (p<0.001) than muscle: 296 ± 257 vs. 0.5 ± 0.4 mg/kg respectively. Secondly, a controlled longitudinal experimental study was carried out to discover whether F affects the biosynthesis of melatonin, (MT), during pubertal development using the excretion rate of urinary 6-sulphatoxymelatonin, (aMT6s), as the index of pineal MT synthesis. Urine was collected at 3-hourly intervals over 48 hours from two groups of gerbils (Meriones unguiculatus), low-F (LF) and high-F (HF) (12 f, 12 m/group): under LD: 12 12, from prepubescence to reproductive maturity (at 9-12 weeks) to adulthood, i.e., at 7, 9, 11 1/2 and 16 weeks. The HF pups received 2.3 ug F/g BW/day from birth until 24 days whereafter HF and LF groups received food containing 37 and 7 mg F/kg respectively and distilled water. Urinary aMT6s levels were measured by radioimmunoassay. The HF group excreted significantly less aMT6s than the F group until the age of sexual maturation. At 11 1/2 weeks, the circadian profile of aMT6s by the HF males was significantly dimished but, by 16 weeks, was equivalent to the LF males. In conclusion, F inhibits pineal MT synthesis in gerbils up until the time of sexual maturation. Finally, F was associated with a significant acceleration of pubertal development in female gerbils using body weights, age of vaginal opening and accelerated development of the ventral gland. At 16 weeks, the mean testes weight of HF males was significantly less (p<0.002) than that of the LF males. The results suggest that F is associated with low circulating levels of MT and this leads to an accelerated sexual maturation in female gerbils. The results strengthen the hypothesis that the pineal has a role in pubertal development.
Excerpt on the Newburgh-Kingston NY study:

To the best of my knowledge, the Newburgh-Kingston study is the only reference on the efffect of F on the timing of puberty in humans. It is the largest, most ambitious paediatric survey carried out to demonstrate the safety of water fluoridation. The New York State Department of Health initiated the study in 1944 because they realized that there would ultimately be a need for a long-term evaluation of any possible systemic effects as well as the dental changes from drinking fluoridated water over a long period of time.

Similar groups of chidren were selected for long-term observation from Newburgh (fluoridated to 1.0 to 1.2 mg/L in 1945) and Kingston (essentially F-free for the duration of the study). Newburgh and Kingston were chosen because they were well-matched: both situated on the Hudson River about 35 miles apart with similar upland reservoir water supplies; both had populations of about 30,000 with similar demographic characteristics, social and economic conditions, levels of dental care, etc. In Newburgh, out of 817 children (aged from birth to nine years) who were selected in 1945, 500 were examined in 1954-1955; in Kingston, out of 711 children who were selected in 945, 405 were examined in 1954-55.

The medical and dental examinations began in 1944, and were repeated periodically until 1955. An assessment of any possible systemic effects arising from the consumption of fluoridated water was made by comparing the growth, development and the prevalence of specific conditions in the two groups of children as disclosed by their medical histories, physical examinations, and laboratory and radiological evidence. The age of onset of menstruation in girls was used as an index of the rate of sexual maturation.
At the end of ten years, the investigators repored no adverse systemic effects from drinking fluoridated water because no significant differences were found between the results from the two groups. The average age of first menarche was earlier among girls in Newburgh than those in Kingston: 12 years vs. 12 years and 5 months respectively (Schlesinger et al, 1956). Although this difference was not considered important, it does suggest an association between the use of fluoridated drinking water and an ealier onset of sexual maturation in girls. The Newburgh girls had not had a lifelong use of fluoridated water. For the first two years or so, they received unfluoridated water. Furthermore, their only source of F was from the drinking water. (pages 6-7)."
• Note from EC: Excerpts are from the hard copy of Luke's thesis. Any spelling errors are mine.
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