Gisle Fosse

Man, nutrition and mobility: A comparison of teeth and bone from the Medieval era and the present from Pb and Sr isotopes

Naturally occurring isotopic systems, such as strontium (Sr) and lead (Pb), are very useful for characterizing different sources and to produce background information. Norwegian teeth from the Medieval era have 206Pb/204Pb ratios between 18.8 and 18.2, in comparison with present day ratios of between 18.0 and 17.6 showing the impact of Pb from modern industrialization and from traffic. Sr analyses of Medieval teeth show that an individual living in a coastal town on the west coast of Norway can easily be distinguished from one in a rural area at that time. The Sr signature shows that Medieval people lived on local products while present people to a greater degree live on imported or domestic industrially processed food. Medieval and modern teeth from one site give similar Pb signatures and concentrations indicating no increase in pollution over time. However, the impact of industrial pollution can be seen from Pb analyses on contemporary teeth, so that the method can be used to monitor emission of heavy metals from local industry. Whilst the Pb and Sr natural isotopic systems individually provide valuable information, a combination of the two techniques is a very powerful tool in environmental and archaeological research.

Numerical density and distributional pattern of dentin tubules

By a new method the numerical density and distributional pattern of transversely cut dentin tubules and the diameters of their peritubular dentin walls were measured in sections near the dentin-enamel junction (DEJ), midway to the pulp, and near the pulp wall in human premolars. For each section the mean and standard deviation of these variables were expressed. At all three levels the measurements comprised the same bundle of tubules from the DEJ to pulp in the coronal dentin. The number of tubules per square millimeter increased more than three times, and the diameters of peritubular dentin decreased one-tenth, whereas central distances between tubules were halved from DEJ to pulp. Thus the pulpward reduction of intertubular dentin is quantified. The distribution of the tubules is not regularly hexagonal, but the distances between them at each given depth are still very uniform in all directions. The pattern of cross-cut tubules often showed distinct short curved rows. The quantitative method might be used to determine taxonomic affinities.

Cadmium in deciduous teeth of Norwegian children.

Two thousand one hundred and sixty‐nine deciduous teeth were collected from cities, industrialized areas, rural and fishing communities in several Norwegian counties. Teeth from Medieval Bergen were also included. Cd‐analysis revealed that a third of the collected teeth had a level below 60 ng/g. It is suggested that this corresponds to a back‐ground level in an ideal uncontaminated environment. There was no correlation between industrialization or urbanization and tooth‐Cd levels in Norway. Buskerud and Hordaland had the highest county levels. The study did not reveal the sources of Cd absorption or register undue burdens in Norwegian children. It is assumed, however, that different dental levels reflect different degrees of absorption, dependent on Cd‐content in food, beverages and drinking water. The levels presented may serve as references in future research on Cd‐absorption in Norway as it is believed that tooth‐Cd can be used as an index to body burden.

Zinc in primary teeth from children in Norway.

Human primary teeth have been used as indicators of exposure to several heavy metals both in Norway and elsewhere. Local dentists in all 19 counties of Norway collected 2747 primary teeth during 1990-1994. Samples of tooth powder from whole, ground teeth were analyzed for zinc concentration by flame atomic absorption spectrophotometry. The overall geometrical mean was 144.5 micrograms of Zn/g of tooth substance (S.D. = 1.6). The result represents a small increase (5.2%) compared with a similar investigation in the 1970s. However, the mean zinc concentrations in the geographically matching parts of the two materials did not differ significantly. The variation in tooth zinc concentrations between the different counties declined from the 1970s to the 1990s. We found no correlation between the tooth zinc concentration and available environmental data on zinc in drinking-water, discharge of zinc from industrial point sources or population density in the same geographical areas. The zinc concentrations varied significantly with caries status, tooth type and root length. Few samples had a zinc concentration below 90 micrograms/g, indicating that most children consume sufficient zinc. Some very high values could not immediately be explained, but may be caused by contamination from zinc-containing dental restorations.

Analysis of individual, intraspecific and interspecific variability in quantitative parameters of caprine tooth enamel structure

Qualitative and quantitative features of mammalian tooth enamel structure are increasingly being used in taxonomic and phylogenetic analyses, although the variability shown by these traits has not received adequate consideration. This study evaluates the variability displayed by nine quantitative parameters in deep, intermediate, and superficial molar enamel in the closely related bovids Ovis aries and Capra hircus. These parameters are assessed in terms of the absolute and/or relative variability evinced at a given depth within a single individual, among conspecific individuals, and between species samples. The degrees of relative variability expressed at a given depth are comparable among conspecific individuals and between taxonomic samples. Nevertheless, in many instances, there are significant differences in absolute variability amongst individuals. Also, in four parameters for which individual specimen averages could be calculated, the equality of these means among conspecifics can be rejected. Variability is not equivalent at different enamel depths. The null hypothesis of equality of individual, conspecific variances can be rejected most commonly for parameters measured in deep and superficial enamel, and coefficients of variation also tend to be higher for deep and superficial enamel than for enamel of intermediate depth. The greater variability displayed by deep and especially superficial enamel may be related to the initial onset and the terminal phase of ameloblastic secretory activity. Taxonomic and phylogenetic analyses that utilize quantitative data on enamel structure are valid only if comparisons have been made at equivalent enamel depths.

Lead, cadmium, zinc and copper in deciduous teeth of norwegian children in the pre‐industrial age

By restoration of the 12th century Uvdal stave church in Buskerud county during the summer of 1978, numerous graves were uncovered underneath the floor. The burials had occurred within a time span of more than 600 years, terminating in the year 1804. Seventy‐nine deciduous teeth were collected and analysed for trace elements. It was concluded that there has been an increase of lead in the environment in Norway, concomitant with urbanization and industrialization, while no such increase of cadmium has occurred. It was further concluded that zinc supply was uniform and optimal in preindustrial Uvdal parish, and that this may not be so in many modern rural districts of Norway.

Prism Size in Tooth Enamel of Some Late Cretaceous Mammals and Its Value in Multituberculate Taxonomy

Teeth from specified members of the two suborders of Late Cretaceous Multituberculata and two Late Cretaceous therians were studied. The enamel was prismatic on all teeth. In the therian representatives and the representatives of the suborder Ptilodontoidea of the Multituberculata, the prism diameters and densities per unit area were similar to those of recent mammals. In the representatives of the suborder Taeniolabidoidea the prisms were very large and their density per unit area was 5 to 8 times lower than in recent mammals. It is suggested that gigantoprismatic enamel is a characteristic of Taeniolabidoidea and could be used as a taxonomic criterion in multituberculate systematics.

Lead and cadmium in teeth, bone and kidneys of rats with a standard Pb‐Cd supply

Male Wistar rats received a combination of 25 ppm PbCl2 and 5 ppm CdCl2 in drinking water at different developmental stages. Pb and Cd levels of incisors, molars, epiphyses, diaphyses and kidney cortex were recorded by atomic absorption spectrophotometry. The results confirmed that Pb has an affinity for hard tissue and especially to teeth, but it also accumulated in soft tissues under the above conditions. In addition, the results indicated none or only a moderate placental or mammary barrier for Pb, and suggested a high absorption of lead from the intestine of sucklings. The results also confirmed that kidney cortex is a primary target for Cd, and indicated that Cd has crossed the placental and mammary barriers to some degree. The positive significant correlation between Cd levels in molars and kidney cortex suggested that rodent molars indicate a degree of Cd absorption, whereas incisors do not. It is supposed that rodent molars are comparable to human deciduous teeth. It is thus confirmed that human d...

Cadmium content of indicator and target organs in rats after graded doses of cadmium

Eleven groups of inbred Wistar rats, five males and five females in each group, received graded doses of CdCl2, from 0–25 ppm, in the drinking water from conception until sacrifice at ten weeks of age. Litter‐size, weight and water consumption were recorded at different ages of the animals. The Cd levels of indicators as blood, hair, incisors and molars, and target organs as femur, kidney cortex, liver, spleen, heart, gastrocnemius muscle and adrenal glands were recorded by atomic absorption spectrophotometry. Cd in the drinking water had no influence on number of animals in each litter, water consumption and growth of the animals. The results further confirmed that the primary target organs of Cd were the soft tissues, but that Cd can to some degree accumulate in teeth and bone, especially molars. The Cd content of all tissues, both indicators and targets, was positively and significantly correlated with dose. The positive significant correlation between the Cd levels of hair or molars, and every target ...

Zinc and copper in deciduous teeth of Norwegian children

About 2160 deciduous teeth were collected from cities, industrialized areas, rural and fishing communities in 14 Norwegian counties. Teeth from Medieval Bergen were also included. Zn‐analysis revealed that the majority of the collected teeth had a level of 122 μg/g. It is suggested that this corresponds to a natural back‐ground level and reflects optimum Zn‐intake. The analysis revealed, however, that urbanization and industrialization increase Zn‐absorption and that there was a significant positive correlation between zinc and lead in the teeth with an extremely high Zn‐level. It was also inferred from the results that about 0.41 percent of Norwegian children from 7 to 12 years of age suffer or have suffered from a Zn‐deficit. There was no correlation between industrialization or urbanization and tooth‐Cu in Norway. It was doubted that tooth‐Cu reflects amount of absorption below toxic levels. It was intimated, however, that a Cu‐level of 400 μg/g in deciduous teeth indicate undue absorption combined wit...