Timing the Neolithic transition: the application of fluoride dating at Tell Halula,Syria

The study of Near Eastern Neolithic villages provides a unique means of tracing subsistence strategy, population growth, health, and emerging social inequality associated with agricultural origins. However, disentangling these patterns requires a detailed comprehension of the chronological placement of individual households in the site. In this paper, we present a test to determine the reliability and applicability of the fluoride dating method (a relative dating method) on human dentition of 40 samples from 28 Pre-Pottery Neolithic B (or PPNB) burials from the site of Tell Halula, in Syria. This method, applied here for the first time on a Neolithic Near East case study, is an alternative when other dating methods, like radiocarbon dates, do not provide the required temporal resolution to address particular research problems. Nonetheless, the results obtained in the fluoride analysis show how both the age at death of individuals, and the integrity of the burial plug enormously affect the amount of fluoride absorbed by teeth, so that only a small subset of the full dataset was suitable for fluoride dating. Although the distribution of fluoride values of dentine from the small sample of burials from suitable contexts matches the expected chronology, and corroborates the hypothesis that the occupation at Halula extends from the Middle to the Late PPNB, our analysis illustrates the need for a better understanding of the different sources of error in fluoride dating to improve the method itself, and to obtain more reliable fluoride chronologies.     

硫酰氟在博物馆藏品熏蒸中的应用

硫酰氟已广泛用于建筑物熏蒸剂,为探索能否应用于博物馆馆藏品熏蒸,为此通过对硫酰氟物化性能、杀虫机理、药效毒理、安全指标及环境影响等方面的分析与评估,对硫酰氟在博物馆藏品熏蒸方面应用的适用性进行了科学论证,对其熏蒸技术和方法进行了总结和完善。甘肃省博物馆馆藏民族服饰、毛织品、皮革文物以及木质橱柜的熏蒸应用效果表明,硫酰氟作为新型的文物熏蒸剂,不仅在杀虫机理及毒理学上科学可行,而且技术与方法简单、实用、易于掌握,博物馆领域应用前景看好。     

Why did the ancient inhabitants of Palmyra suffer fluorosis?

The skeletal remains uncovered from the 2nd and 3rd century underground tombs of Palmyra, Syria, retain traces of arthritis and mottled enamel. A brown discoloration was also observed in the teeth. In order to clarify that these facts can be related to fluorosis, the teeth excavated from Tomb C and F in the Southeast Necropolis were analyzed. The fluoride contents of the fluorosis-suspected teeth (0.56 ± 0.16% (n = 7)) were higher than those of normal teeth (0.16 ± 0.18% (n = 7)). The highest content (0.85%) proved that 22% of the hydroxide in apatite was substituted by fluoride. The fluoride concentrations of the natural water including deep well water available today in this area ranged from 0.3 to 3.0 mg l⁻¹. The highest fluoride concentration was found to be regulated by the dissolution equilibrium of fluorite, CaF₂, through the process of evaporation and concentration in this arid region. Because of the common ion effect by calcium ions in a high concentration, the fluoride concentration was lower than that expected from the solubility product of fluorite (8.2 mg l⁻¹). The mechanism of this process has probably remained unchanged since ancient times and therefore the drinking water used by the ancient people of Palmyra was estimated to contain fluoride at a level causing fluorosis.