Fluoride content of selected human food, pet food and related materials

Exploring sex differences in diets and activity patterns through dental and skeletal studies in populations from ancient Corinth, Greece

Sex and temporal differences are assessed in relation to dietary habits and activity patterns in three ancient populations from Corinth, Greece. The skeletal sample spans time from the Geometric to the Early Byzantine Period (9th c. BCE-5th c. CE). Dental caries and tooth wear have been proven to be reliable dietary indicators. Similarly, spinal osteoarthritis, spinal facet remodeling and Schmorl's nodes, have been used to infer activity patterns.

Aluminium and fluoride in hospital daily diets and in teas

The levels of aluminium and fluoride have been determined in hospital daily diets including breakfast, dinner and supper, as well as in black teas and herbal teas purchased from the local market. In tea, aluminium was determined directly in a sample solution by atomic absorption spectroscopy using nitrous oxide and an acetylene flame. For analysis of the hospital diet, samples containing lower levels of aluminium were analysed using a spectrophotometric method which measured aluminium in the form of a 8-hydroxyquinoline complex. Decomposition of the samples was achieved using a mixture of concentrated acids [nitric (HNO3), perchloric (HClO4) and sulphuric (H2SO4)] in platinum dishes. Fluoride was assayed by spectrophotometry using a microdiffusion procedure with a mixture of concentrated HClO4 and silver sulphate, trace amounts of the released fluoride [as hydrogen fluoride (HF)] were trapped on the alkaline surface of a Petri dish and then determined in the form of an alizarin-fluoride complex. The mean level of aluminium found in hospital daily diets amounted to 21.3 +/- 12.3 mg and the mean level of fluoride was 1.38 +/- 1.12 mg per adult person. In the 16 samples of commerically available brands of black teas, the levels of aluminium and fluoride ranged from 445 to 1552 ppm (mean = 897 +/- 264 ppm) and from 30 to 340 ppm (mean 141 +/- 85 ppm), respectively. In six herbal teas, the mean levels of aluminium and fluoride were lower, and amounted to 218.9 +/- 150.7 ppm and 6.0 +/- 6.9 ppm, respectively. This study has shown that concern about a high intake of aluminium and fluoride from these foods is unfounded.

Factors influencing the bioavailability of fluoride from calcium-rich, health-food products and CaF2 in man

After single, oral doses, 8 h profiles of fluoride (F) concentrations in plasma were determined in healthy human volunteers. Bioavailability of F from bone-meal, calcium and CaF2 tablets was evaluated in relation to that of NaF. Tablets were administered either whole or as a finely-ground powder, either to fasting subjects or with breakfast. Availability was lowest from whole tablets taken by fasting subjects, and highest from powdered substances given with breakfast. Mean F availabilities ranged between 7.2 and 39 per cent with bone-meal tablets, between 20 and 59 per cent with Ca tablets, and between 0 and 47 per cent with CaF2 tablets.

An experimental study of bio-availability of fluoride from dietary sources in man

After single, oral doses, 8 h profiles of fluoride (F) concentrations in plasma and saliva, and 24 h urinary excretions were determined in healthy adult volunteers. Bio-availability of F from dietary sources was evaluated in relation to that of NaF. Between 2 and 10 mg of F administered all 3 variables were dose-dependent. However, digestion, the chemical state of F, and interaction with accompanying foods may modify the kinetics of F passage through the human body. Low bio-availabilities were observed for most solid foods such as fish and algal flour and for mammalian and fish bones, when used as typical components of fluoride-rich foods such as meat- and fish-products. This data is important in the determination of optimum levels of F supplementation in human nutrition for caries-prevention programmes.