Fluoride ingestion

C. The symptoms are characteristic of a person chronically exposed to vapors released from elemental mercury. Since the dental technician may handle elemental mercury, including mishandling, the symptoms presented may occur. While the technician may be exposed to solvent vapors released from dental adhesives, the symptoms are not characteristic of this type of exposure. Fluoride toxicity would not be expected because these are not symptoms associated with fluoride ingestion, and the patient and not the technician would be most likely exposed to quantities high enough to cause any symptoms. The technician has little exposure to li-docaine, and the symptoms are not typical of lido-caine toxicity. 

Fluorine is available to humans, plants and animals mainly in the form of fluoride ion (F ). Body fluoride status depends on numerous factors, including the total amount of fluoride ingested daily, its bioavailability and metabolism. The adequate intake (Al) of fluoride from all sources is set by the Standing Committee on the Scientific Evaluation of the Dietary Reference Intakes at 0.05 mg/day/kg body weight this intake is recommended for all ages above 6 months, because it confers a high level of protection against dental caries and is not associated with any known unwanted health effects [8]. 

Fluoride is a cumulative toxin, which accumulates in mineralized tissues, notably in the lattice of bone and tooth crystals [8,39]. The biological effects in humans due to chronic fluoride ingestion depend not only on the total dosage and duration of exposure, but also on associated factors such as nutritional status, functional status of the renal tissue and interaction with other trace elements [41]. The effect of... 

Dental or enamel fluorosis is an irreversible dose-response effect caused by fluoride ingestion during the pre-eruptive development of teeth. The pre-eruptive maturation of crowns of the anterior permanent teeth, which are of most concern aesthetically, is complete and, together with the risk of fluorosis, is over by the age of 7-8 years [46,47]. After the enamel has completed its pre-eruptive maturation, it is no longer susceptible. Therefore, fluoride intake up to the age of 7-8 years is of most interest. Although it is usually the permanent teeth that are affected, occasionally the deciduous teeth may be also involved. 

Excess fluoride ingestion damages developing teeth, causing oiotiling. cliolky-white coloration, and pitting. 

Dental caries have been prevented when fluoride tablets were administered in a school-based program. After two or more years of fluoride ingestion, protection against dental caries ranged from 20 0%. In an extended trial of fluoride tablets reported in the literature, there was a 36% reduction in dental caries after 8 years. ... 

In a child, there were tetanic spasms and a convulsion more than 12 hours after fluoride ingestion, with a normal serum calcium. It is advisable that patients with intoxication should remain under surveillance for at least 24 hours, after the usual acute symptoms such as vomiting and diarrhea have settled (SEDA-10, 439). 

Augenstein WL, Spoerke DG, Kulig KW, et al. (1991) Fluoride ingestion in children A review of 87 cases. Pediatrics 88 907-912. 

This chapter describes how individuals with severe enamel fluorosis (mottled tooth enamel) became associated with fluoride in the public water supply and protection from dental caries. A comparison of caries experience with the fluoride content of public water supplies and enamel fluorosis in adolescents indicated that 1 pg fluoride/mL (1 part/million) in the water provides caries protection with minimal enamel fluorosis (sect. 1). One mechanism is the spontaneous isomorphic replacement of apatite s hydroxide anions with fluoride, which reduces enamel solubility. A second is fluoride-mediated inhibition of enolase, which retards bacterial acid production at teeth surfaces. These findings led to the use of fluoride in toothpastes, which provides better protection from caries at tooth surfaces than water fluoridation alone (sect. 2). The chapter concludes with a discussion of potentially harmful effects of fluoride ingestion (sect. 3). 

Pendrys DG (2001) Fluoride ingestion and oral health. J Nutr 17 979 -980. 

A. Oral fluoride ingestion. Administer calcium-containing antacid (calcium carbonate) orally to complex fluoride ions. 

Fluoride dust (as fluoride) Irritating to eyes and respiratory tract. Workers exposed to levels 10 mg/m suffered nasal irritation and bleeding. Lower-level exposures have produced nausea and eye and respiratory tract irritation. Chronic overexposures may result in skin rashes. Fluorosis, a bone disease with chronic high-level fluoride ingestion, is not associated with occupational dust inhalation. See also p 200. 2.5 mg/m (as F) 250 mg/m (as F) Appearance varies with the compound. Sodium fluoride is a colorless to blue solid. 

Phosphate rock dust, fluorides, acid, and radioactive elements are the main health hazards in a phosphoriir acid plant. The threshold limit value (TLV) of industrial exposure to hydrogen fluoride for daily intake has been established at 5-6 mg/Nm however, considering other inputs from drinking water and food, the reasonable limit of daily intake has been established at levels of 2 mg/ day of fluorides ingestion. 

Fluoride excretion. About half of the soluble fluoride ingested is rapidly excreted mainly via the urine. 

Although fluoride is very toxic at high concentrations, fluorine is a trace element naturally present in the diet which is essential for the formation of healthy bones and teeth, and resistance to dental caries is substantially reduced in children whose intake is inadequate at the stage of enamel formation. Much of the fluoride ingested by humans dependent on water from wells must orginally have been obtained from the water supply. It has been established that the optimal level of fluoride in drinking water, for the prevention of dental caries, is about 1 ppm. 

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