ANALYTICAL LETTERS Vol. 37, No. 13, pp. 2819–2834, 2004
ENVIRONMENTAL ANALYSIS
Statistical Treatment of Trace Element Data from Modern and Ancient Animal Bone: Evaluation of Roman and Byzantine Environmental Pollution Patrick Degryse,1, * Philippe Muchez,1 Bea De Cupere,2 Wiu Van Neer,2 and Marc Waelkens3 1
Fysico-chemische Geologie, K.U. Leuven, Heverlee, Belgium Koninklijk Museum voor Midden-Afrika, Tervuren, Belgium 3 Departement Archeologie, K.U. Leuven, Leuven, Belgium
2
ABSTRACT Through chemical analysis of ancient animal bone found at the archaeological site of Sagalassos, and through comparison of the analytical data with that from modern bone and feed from the same location, conclusions on the ancient livestock are made. Samples of ancient and modern goat bone as well as Quercus coccifera were analyzed using Inductively Coupled Plasma – Mass Spectrometry (ICP-MS). After evaluation of the consistency of the chemical characteristics of different types of modern
*Correspondence: Patrick Degryse, Fysico-chemische Geologie, K.U. Leuven, Celestijnenlaan 200C, 3001 Heverlee, Belgium; E-mail:
[email protected]. be. 2819 DOI: 10.1081/AL-200032082 Copyright # 2004 by Marcel Dekker, Inc.
0003-2719 (Print); 1532-236X (Online) www.dekker.com
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Degryse et al. bone in one individual, it is decided to use the trace element data of long bone for statistical treatment. After evaluation of the degree and effects of diagenesis in the fossil bone, it is concluded that trace element data are useful indicators for anthropogenic palaeoenvironmental pollution, as a distinction could be made between elements that occur naturally in the bedrock and those that can be linked to industrial pollution. The occurrence or depletion of the latter elements in fossil bone, show diachronic changes in the chemical composition of the goat bones which can be explained in function of the changing catchment area from which the animals were obtained through time. It is conceivable that during periods of insecurity, such as the fifth to sixth century A.D. in the area of Sagalassos, animal herds were kept closer to the ancient town and would hence take up more pollutants with the ingested food. A lower uptake of pollutants during the fourth century, a rich and secure period in the history of the city, can be explained by a wider catchment area from which the goats were obtained. Key Words: ICP-MS.
Archaeology; Biological samples; Heavy metals; Pollution;
INTRODUCTION Archaeozoological studies, the analysis of faunal remains from archaeological sites, aims at reconstructing the past relationship between man and the animal environment. Paleoeconomic and paleoenvironmental inferences can be made through the identification and quantification of animal remains found at archaeological sites, but information can also be derived from the chemical composition of the faunal material itself. As this biomaterial registers diets or environmental conditions occurring during its lifetime in modifying its chemical composition, the latter reflects dietary customs and climatic conditions.[1] Contamination due to the uptake and diffusion of chemical elements or other alteration processes, like dissolution or erosion, can change the composition and distort the results of environmental and dietary studies. Compositional studies on fossilized bone have provided information on various aspects of the paleoenvironment as a result of diagenetic changes during the fossilization process of buried bone.[1,2] The nature and degree of diagenesis have been evaluated through the study of changes in the fossil bones’ chemical composition.[3] In general, the chemical composition of ancient bone can provide information on the history of the bone, but also an overall paleoenvironmental interpretation of the ancient site can be made.[1,3] The archaeology of Sagalassos (SW Turkey) is the subject of an interdisciplinary research project coordinated by the Katholieke Universiteit
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Leuven since 1986.[4] The Hellenistic to Byzantine site is located in the Taurus Mountains of southwestern Turkey, within the ancient region of Pisidia. In antiquity, from Hellenistic to early Byzantine times, Sagalassos may not have been much more than a provincial primus inter pares or a regional pole of attraction. However, the systematic and interdisciplinary reconstruction of the ecology and economy of the site and its territory has increased our understanding of the settlement and its inhabitants beyond the traditional aspects of research of classical archaeology in Asia Minor.[4] Sagalassos appears in the limelight of history in 333 B.C. , when the town and the region of Pisidia were conquered by Alexander the Great. Thereafter, Pisidia witnessed a sequence of Hellenistic kings, but when the Attalids bequeathed their kingdom to Rome, the region of Pisidia was joined to the Republican province of Asia and later Cilicia. In 25 B.C. , Rome decided to incorporate the region into its empire. The Pax Romana introduced by the soldiers of Augustus would last for centuries. The town seems to have remained prosperous for centuries, but its glory is shattered by an early sixth century A.D. earthquake. Afterwards, the settlement may have been reduced to the status of a village. The site was largely abandoned after the middle of the seventh century A.D. , when a dramatic sequel of epidemics, Arab raids, and another major earthquake took its toll.[5,6] One of the major research topics within the interdisciplinary research focuses on the impact of the economic network of the town on a local to supraregional scale. Apart from exploiting the obvious resources such as domestic stock keeping,[7] agriculture, and forestry, the extensive territory of Sagalassos offered a rich variety in mineral resources[8] supplying a large ceramic manufactory,[9] glass and metal workshops,[10] and the building industry.[11] It has been shown that all these activities had a major impact on the soil geochemistry of the ancient city.[10] Knowledge of the various contents in trace elements in the body of domestic animals constitutes an indicator useful for the evaluation of environmental pollution with harmful substances.[12] It is the intention of this paper to evaluate the use of various trace elements in modern and ancient bones of the domestic goat (Capra aegagrus f. hircus) as an indicator of ancient natural and unnatural pollution in and around the city of Sagalassos from Roman to Byzantine times.
METHODOLOGY Sampling Samples of fossil goat bones were taken from excavation layers inside the city of Sagalassos. Twenty-eight samples were taken from different contexts,
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dated to three chronological periods: the first half of the second century A.D. (2A), the first half of the fourth century A.D. (4A), and the end fifth to the first half of the sixth century A.D. (5E –6A). As a reference material, 20 bones from healthy goats of a present-day herd were taken. These animals are known to have grazed nearby the archaeological site—to the west of the ruins—for most of their lives.[13] The skeletons (register numbers RMCA 97.10.M11, 13– 20) from which these modern samples were taken, are stored at the Royal Museum for Central Africa (Belgium). Also, 8 samples of their main feed, Quercus coccifera, were taken for analysis.
Measurement The modern goat bones were defleshed and macerated in water before analysis. Plant specimens and ancient bones were mechanically freed from adhering soil particles. From all bone, samples weighing 2 g were taken from dense, cortical tissues. Samples were rinsed with deionized water, dried at 408C, and washed with diethyl ether in a sonic bath for one hour and dried. The samples were then ultrasonically treated with 99% formic acid for 5 min and rinsed with deionized water. This step was repeated three times to dissolve all precipitates on the outer and inner surface of the samples (e.g.,[14,15]). Dried samples of bone and plant material were then combusted at 7508C in a muffle oven for 8 hours and the remaining ash was homogenized in an agate mortar. Ash samples of 100 mg were dissolved in 5 ml HNO3conc on a hotplate. Samples were evaporated to dryness and the residue was dissolved in 25 ml 1 M HNO3. Samples were diluted 1/10 with 1 M HNO3 ultrapure and analyzed on a Hewlett Packard (Agilent) 4500 Inductively Coupled Plasma – Mass Spectrometer (ICP-MS). For quality control, the measurements were checked against blanks and 1400 Bone Ash standard material provided by NIST.
Data Analysis Element data were statistically treated using Pearson correlations on Systatw software. For calculations, the log was taken for the non-Gaussian distributed elements Cr, Mn, Ni, Pb, and Zn. The log transform creates a more normal distribution than the strongly positively skewed data. For the data set of the three chronological groups of archaeological bone, the nonparametric Kruskal-Wallis test was used on Systatw software to indicate statistically significant differences between the three chronological groups of archaeological bone studied (e.g.,[16]).
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RESULTS The trace element data of the modern and archaeological bone and of the main feed (Quercus coccifera) are summarized in Table 1. First, it was verified if among the modern samples of goat bones, differences occurred in chemical composition of the various skeletal elements used. Long bones (i.e., metacarpus, metatarsus, and radius), as well as calcaneum, astragalus, and the first phalanx of the same individual (97.70.M16) were analyzed. It is clear that for the long bones and the first phalanx, the variation is minimal and well within the precision of the ICP-MS analytical technique. Some variation though minimal, seems to exist for the other two bone elements analyzed (calcaneum and astragalus) for the elements Na, Mg, Cu, Zn, and Ba. Therefore, for the purpose of this study, long bones were preferably used for analysis. Second, individual variation was tested by analyzing the same skeletal element from different modern animals, (i.e., metacarpus and metatarsus from 4 individuals [97.10.M11, 16, 18, 19] and radio-ulna from 9 individuals [97.70.M11, 13 –20]). It is clear that the variation in trace element data for these modern individuals is minimal, owing to their identical feeding behavior. Comparing modern bone from the area of Sagalassos with ancient bone from the excavations, allows us to determine the effect of diagenetic processes. Mg and Na are present in higher amounts in modern bone (a median of respectively 6918 ppm and 8243 ppm) than in fossil samples (a median of respectively 2014 ppm and 4328 ppm). On the other hand, the fossil samples are clearly enriched in Sr and Ba compared to the modern bone (respectively 76 and 186 ppm in modern bone versus 715 and 288 ppm in ancient bone). It is clear that in the modern goat bone, some specimens are severely enriched in Cu (max. 57 ppm), Pb (7 ppm), and Zn (185 ppm). It can be observed that the modern bone material is overall enriched in Pb and Zn (compare to 12). It is striking, in contrast to the anomalous elements, that most modern goat bone does not show a Cr content above the detection limit of 1 ppm adopted for this study. Modern goat bone samples show a low Co (max. 1 ppm), Mn (max. 3 ppm), and Ni (max. 7 ppm) content. In the modern bones, As and Cd were not present in amounts above 1 ppm. From the trace element data of the main feed of the individual goats, it is clear that the elements Co (max. 5 ppm), Cr (max. 12 ppm), Cu (max. 293 ppm), Mn (max. 906 ppm), Ni (max. 83 ppm), Pb (max. 10 ppm), and Zn (max. 1141 ppm) are present in the local plant material. The trace element data of the fossil bone samples reveal that these are enriched, in comparison to the modern bone, in As (max. 7 ppm), Cr (max. 16 ppm), Cu (max. 436 ppm), Mn (max. 1245 ppm), Ni (max. 33 ppm), Pb (max. 260 ppm), and Zn (max. 330 ppm). However, it seems that some differences in the trace
Na
Identical bone type, different individuals metacarpus (n ¼ 4) mean 8775 7453 b.dl. st.dev. 82 437 – metatarsus (n ¼ 4) mean 8564 7226 b.dl. st.dev. 595 175 – b.dl. – b.dl. –
b.dl. –
b.dl. b.dl. b.dl. b.dl. b.dl. b.dl. – –
b.dl. 1 b.dl. – –
Co
b.dl. –
b.dl. b.dl. b.dl. b.dl. b.dl. b.dl. – –
Mn
Different bone types, single individual metacarpus 8718 7028 b.dl. metatarsus 8773 7095 b.dl. radio-ulna 9073 6920 b.dl. astragalus 5990 5075 b.dl. calcaneum 5660 4830 b.dl. phalanx 1 7790 6915 b.dl. mean 7667 6310 – st.dev. 1494 1057 –
Cr
b.dl. 3 1 – –
4830 8065 6918 6556 956
Mg
b.dl. 2 b.dl. – –
Modern Bone (n ¼ 20) min 5660 max 9475 median 8243 mean 7794 st.dev. 1289
Sample
b.dl. –
b.dl. –
b.dl. b.dl. b.dl. 4 5 b.dl. – –
4 7 5 5 1
Ni
12 4
12 3
9 10 25 19 57 9 21 19
8 57 12 15 10
Cu
116 23
129 38
100 100 73 148 163 118 117 34
73 185 127 129 27
Zn
b.dl. –
b.dl. –
b.dl. b.dl. b.dl. b.dl. b.dl. b.dl. – –
b.dl. b.dl. b.dl. – –
As
75 3
76 3
73 76 73 63 65 78 71 6
54 306 76 82 50
Sr
b.dl. –
b.dl. –
b.dl. b.dl. b.dl. b.dl. b.dl. b.dl. – –
b.dl. b.dl. b.dl. – –
Cd
182 12
187 6
180 185 187 408 318 202 247 95
69 408 186 205 84
Ba
4 1
4 1
4 3 4 2 4 5 4 1
2 7 4 4 1
Pb
Table 1. Trace element analysis data of the modern and fossil goat bone and modern Quercus coccifera. b.dl: below detection limit of 1 ppm adopted for this study.
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(n ¼ 9) 7501 1360
6th Ctry 1955 4513 3204 3316 936
Modern Plants (n ¼ 8) min 410 max 4261 median 1098 mean 1527 st.dev. 1266
Late 5th - early min max median mean st.dev.
b.dl. –
(n ¼ 10) 1072 b.dl. 3705 7 1564 2 1874 – 858 –
6305 869
27295 80775 47166 49226 18151
2 12 7 7 3
281 906 362 431 202
3 148 18 32 –
(n ¼ 8) 1146 2 2463 16 1727 12 1748 11 533 5
A.D.
15 1245 541 592 446
1 670 140 – –
b.dl. –
b.dl. 3 1 – –
First half 4th Ctry A.D. (n ¼ 10) min 4647 1963 max 6548 3318 median 5270 2296 mean 5357 2467 st.dev. 665 519
Second half 2nd Ctry A.D. min 2095 max 6053 median 4059 mean 3752 st.dev. 1188
Archaeological Bone
radio-ulna mean st.dev.
1 5 3 3 2
b.dl. 1 1 – –
b.dl. 2 1 – –
b.dl. 2 b.dl. – –
b.dl. –
9 83 50 46 27
3 10 8 8 3
4 27 12 13 8
4 33 18 18 10
5 1
59 293 156 170 80
34 81 64 61 15
10 44 27 28 11
21 436 50 95 126
16 5
228 1141 526 542 301
105 330 144 164 73
87 153 115 120 20
100 156 122 126 21
125 27
b.dl. 1 b.dl. – –
2 6 4 4 2
b.dl. 7 5 5 2
b.dl. 5 2 – –
b.dl. –
13 1846 423 599 663
557 1470 914 975 266
315 1110 563 658 238
295 867 662 635 178
71 9
b.dl. 1 b.dl. – –
b.dl. b.dl. b.dl. – –
b.dl. b.dl. b.dl. – –
b.dl. 1 b.dl. – –
b.dl. –
253 7338 309 1204 2481
171 391 314 302 83
144 285 241 235 47
251 567 348 383 101
183 103
2 10 3 5 4
3 57 6 13 –
1 10 4 4 3
3 260 7 33 –
3 1
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element content (e.g., for Cr, Cu, Mn, Ni, Pb, and Zn) of the three chronological groups of fossil bone (the first half of the second century A.D. , the first half of the fourth century A.D. , and the end fifth to the first half of the sixth century A.D. ) exist.
DISCUSSION Grazing animals readily pick up contaminants from the environment on which they live and feed.[16] Bone is moreover well known to accumulate these polluting trace elements (e.g.,[12,16]). When the modern bone is compared to the main feed of the goats, it is clear that the enrichments in Cu, Pb, and Zn in the bone correspond to those in the plant material. It can be assumed, that As (max. 1 ppm), Cd (max. 1 ppm), and Co (max. 5 ppm) present in low amounts in the plant specimens, has not been retained in significant amounts in the bone of the modern goats. The occurrence of all the aforementioned trace elements in the plant specimens is not surprising. First, the ancient city of Sagalassos was built on an ophiolitic bedrock, naturally enriched in among others Cu.[17] Second, ancient activities such as metallurgy, manuring, and “waste management” have always had a major geochemical impact on the environment.[10,18] For instance, lead and copper compounds were used in the elemental form since prehistory and zinc was alloyed with copper.[18] It has been shown that the underground at Sagalassos, and more specifically the Roman to Byzantine excavation layers, are enriched in Cu, Pb, and Zn.[10] Comparison of the modern bone from the area of Sagalassos with the fossil bone from the excavation layers, allows us to determine the effects of diagenetic processes. Generally, Ba and Sr are typically significantly higher in fossil samples relative to recent material.[19] Mg, present in the bone collagen, is removed during diagenesis while the Ba and Sr contents increase with the recrystallization of the buried bone. Calculations of correlations between the chemical data reveal the close relation of Ba, Mg, Na, and partly Sr (Fig. 1). A correlation is observed between the element Cr on the one hand, and Na, Mg, and Sr on the other hand. It is likely that some Cr was incorporated in the fossil bone during diagenesis. However, some element concentrations in the ancient bone from Sagalassos cannot be related to diagenetic processes, as there is no correlation with the normal chemical processes described above. For instance, the As, Cu, Pb, and Zn contents of the ancient bone of Sagalassos are independent of the contents in elements related to diagenetic processes such as Ba, Mg, Na, and Sr (Fig. 2). The lack of intercorrelation between the elements As, Cr, Cu, Ni, Pb, and Zn in the fossil bone, also excludes the possibility as would the contents in the bone
Figure 1. Biplots as an example for the correlation between the elements Ba, Mg, Na, and Sr in fossil bone.
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Figure 2. Biplots as an example for the absence of correlation between the diagenetically determined elements Na and Mg and the diagenesis-independent elements As, Cu, Pb, and Zn in fossil bone.
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of the latter elements be caused by residual soil material on the bone (compare to [10]). As also, diagenesis has not caused the introduction of the elements As, Cu, Pb, and Zn in the fossil bone, it can be concluded that they were inherent to the bone during its lifetime. It can be assumed that they were ingested by the ancient animals through their feed, thus, from their natural environment, and were accumulated in the skeleton. This is a process similar to the one observed in the present-day bone for some elements. The Cr and Ni in the soil around Sagalassos can be solely attributed to the natural geological situation, as these metals were not worked in ancient times. In the territory, chromite deposits have been identified[10] and a large part of the bedrock around the city and on the territory consists of ultrabasic ophiolitic material.[17] As described earlier, associated high contents in As, Mn, Pb, and Zn in the soil of Sagalassos can be attributed to ancient pollution.[10] The Cu in the soil may have entered the environment both through artisanal activity as well as from the ultrabasic bedrock. It can be noted that the Cr, Cu, Mn, Ni, Pb, and Zn contents vary between the three chronological groups of fossil bone (Table 1, Fig. 3). To identify possible statistically significant differences between the trace element contents of the three chronological groups of archaeological bone analyzed, the nonparametric Kruskal-Wallis test was applied on these data (e.g.,[16]). The results are given in Table 2. The Kruskal-Wallis test results are expressed as probabilities that the given groups of data are identical for the given element. Significant differences between the trace element content of the chronological groups are due to differences in trace element ingestion from
Figure 3. Variation in Pb, Cu, and Cr content for the three chronological periods of bone [period 1 (black): the second half of the second century A.D. , period 2 (gray): the first half of the fourth century A.D. , period 3 (marbled): the end fifth to the first half of the sixth century A.D. ].
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Table 2. Results of the nonparametric Kruskal-Wallis test on the trace element data for As, Cr, Cu, Mn, Ni, Zn, and Pb for all three chronological groups of fossil bone. As 2nd Ctry A.D. 4th Ctry A.D. 5th– 6th Ctry A.D.
2nd Ctry A.D. 1.000 0.095 0.112
4th Ctry A.D. 1.000 0.621
5th– 6th Ctry A.D. 1.000
Cu 2nd Ctry A.D. 4th Ctry A.D. 5th– 6th Ctry A.D.
2nd Ctry A.D. 1.000 0.013 0.563
4th Ctry A.D. 1.000 0.001
5th– 6th Ctry A.D. 1.000
Ni 2nd Ctry A.D. 4th Ctry A.D. 5th– 6th Ctry A.D.
2nd Ctry A.D. 1.000 0.272 0.016
4th Ctry A.D. 1.000 0.154
5th– 6th Ctry A.D. 1.000
Zn 2nd Ctry A.D. 4th Ctry A.D. 5th– 6th Ctry A.D.
2nd Ctry A.D. 1.000 0.544 0.286
4th Ctry A.D. 1.000 0.091
5th– 6th Ctry A.D. 1.000
Cr 2nd Ctry A.D. 4th Ctry A.D. 5th– 6th Ctry A.D.
2nd Ctry A.D. 1.000 0.039 0.004
4th Ctry A.D. 1.000 0.001
5th– 6th Ctry A.D. 1.000
Mn 2nd Ctry A.D. 4th Ctry A.D. 5th– 6th Ctry A.D.
2nd Ctry A.D. 1.000 0.034 0.155
4th Ctry A.D. 1.000 0.003
5th– 6th Ctry A.D. 1.000
Pb 2nd Ctry A.D. 4th Ctry A.D. 5th– 6th Ctry A.D.
2nd Ctry A.D. 1.000 0.067 0.823
4th Ctry A.D. 1.000 0.039
5th– 6th Ctry A.D. 1.000
the respective environments by the ancient animals. It is clear that the three chronological groups are significantly different for the elements Cr, Cu, Mn, Ni, and Pb (compare to [16]). The groups may not be significantly different for their content in As and Zn. The test was repeated on the groups two by two using the same nonparametric test. The results are shown in Table 3. It is clear that the fossil bone from period 1 is significantly different from that of period 2 for the elements As, Cu, Cr, Mn, and Pb. The fossil bone from period 1 is significantly different from that of period 3 for the elements Cr and Ni. The Pb, Cu, and Zn content, and most likely also the As and Mn
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Table 3. Results of the nonparametric Kruskal-Wallis test on the trace element data for As, Cr, Cu, Mn, Ni, Zn, and Pb for the chronological groups of fossil bone, performed two by two. As Cr Cu Mn Ni Pb Zn
Probability 0.156 0.001 0.003 0.005 0.050 0.073 0.237
content of these two chronological groups of fossil bone, are comparable. Finally, the fossil bone from period 2 is significantly different from that of period 3 for the elements Cr, Cu, Mn, Pb, and Zn. The variation in Cr content of the fossil bone may be due to diagenetic processes. However, the variations in fossil bone chemistry for the elements Cu, Mn, Pb, and Zn must be due to a varying intake of these elements from the environment. This is due to either a difference in feed or in environmental conditions in which the animals were kept. It is remarkable that the chemistry of the polluting elements in the fossil bone from chronological periods 1 (first half second century A.D. ; 2A) and 3 (end fifth to first half of sixth century A.D. ; 5E– 6A) are very similar. Chronological period 2 (first half fourth century A.D. ; 4A) is clearly different from the others. Since the area immediately around the ancient city of Sagalassos is known to have been polluted with Mn, Pb, Cu, and Zn,[10] the results seem to indicate that goats consumed at the site during periods 1 and 3 were kept close to or inside the town. The animals from chronological period 2, however, must have been herded farther away from Sagalossos where grazing areas were less polluted by ancient artisanal activity and may evidently have had a differing bedrock. The differences in soil geochemistry within and immediately around the ancient city versus that on its territory, may hence explain the varying uptake in trace elements in the animal bone. The occurrence of As and Zn in all soil types on the territory of Sagalassos[10] can explain the consistency of the As content in all archaeological bone. The aforementioned results fit well with the archaeozoological data and the general picture of the political and economic changes that Sagalasossos underwent. The town was very prosperous during the fourth century and during that period it is noticed that the contribution of cattle was much higher than in the preceding and following periods when ovicaprines (sheep and goat) were more frequently slaughtered.[7] The heavier reliance on goat and sheep from the fifth century onwards is seen as a reaction of herders towards the less secure situation,
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evidenced amongst others by the erection of a fortification wall in the town.[20] It is conceivable that during periods of insecurity, animal herds were kept closer to town and would hence take up more pollutants with the ingested food. Lower uptake of pollutants during the fourth century can be explained by a wider catchment area from which the goats were obtained. The higher amounts of polluting elements in the goat bones from the second century A.D. indicate that in this period animals were also kept closer to the site. During that period, however, the town was still relatively small and it may therefore not have been necessary to import animals from a farther distance. CONCLUSIONS The trace element analysis of goat bones from modern animals and from specimens dating to three different periods of the Roman and Early Byzantine has shown that the chemical analysis has potential for the study of ancient pollution and husbandry practices. The study of the modern goat bone has demonstrated that the pollutants are found in comparable amounts in various bones of a single individual and, moreover, it was shown that individual variation among goats from a single herd were minimal. A distinction could be made between elements that occur naturally in the bedrock and those that can be linked to industrial pollution. Comparison of the data from modern and ancient bone allowed us to establish elements that do not change significantly due to diagenetic processes. Those elements that can be retained for analysis show diachronic changes in the chemical composition of the goat bones which can be explained as a function of the changing catchment area from which the animals were obtained through time. ACKNOWLEDGEMENTS S. Lens is kindly thanked for chemical analyses. This research is supported by the Belgian Programme on Interuniversitary Poles of Attraction (IUAP 5-09) initiated by the Belgian State, Prime Minister’s Office, Science Policy Programming. This text also presents the results of the Concerted Action of the Flemish Government (GOA 02/2). REFERENCES 1. Reiche, I.; Favre-Quattropani, L.; Calligaro, T.; Salomon, J.; Bocherens, H.; Charlet, L.; Menu, M. Trace element composition of archaeological bones and post-mortem alteration in the burial environment. Nuclear Instruments and Methods in Physics Research B 1999, 150, 656–662.
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2. Denys, Ch.; Williams, C.T.; Dauphin, Y.; Andrews, P.; FernandezJalvo, Y. Diagenetical changes in Pleistocene small mammal bones from Olduvai bed I. Palaeogeography Palaeoclimatology Palaeoecology 1996, 126, 121 –134. 3. Hedges, R.E.M. Bone diagenesis: an overview of processes. Archaeometry 2002, 44, 319 – 328. 4. Waelkens, M.; Paulissen, E.; Vermoere, M.; Degryse, P.; Celis, D.; Schroyen, K.; De Cupere, B.; Librecht, I.; Nackaerts, K.; Van Haverbeke, H.; Viaene, W.; Muchez, Ph.; Ottenburgs, R.; Deckers, S.; Van Neer, W.; Smets, E.; Govers, G.; Verstraeten, G.; Steegen, A.; Cauwenbergs, K. Man and environment in the territory of Sagalassos. Quaternary Science Reviews 1999, 18, 697– 710. 5. Waelkens, M. Romanization in the East. A case study: Sagalassos of Pisidia (SW Turkey). Istanbuler Mitteilungen 2001, 52, 311 –368. 6. Waelkens, M.; Sintubin, M.; Muchez, Ph.; Paulissen, E. Archaeological, geomorphological and geological evidence for a major earthquake at Sagalassos (SW Turkey) around the middle of the seventh century AD. In The Archaeology of Geological Catastrophes; McGuire, B., Griffiths, D., Stewart, I., Eds.; Geological Society of London: London, 2000; Geological Society of London Special Publications 171; 373– 383. 7. De Cupere, B. Animals at ancient Sagalassos. Evidence of faunal remains. In Studies in Eastern Mediterranean Archaeology 4; Brepols: Turnhout, Belgium, 2001; 273. 8. Degryse, P.; Muchez, Ph.; Sintubin, M.; Clijsters, A.; Viaene, W.; Dederen, M.; Schrooten, P.; Waelkens, M. The geology of the area around the ancient city of Sagalassos (SW Turkey). In Acta Archaeologica Lovaniensia Monographiae 12; Sagalassos, VI; Waelkens, M., Poblome, J., Eds.; Leuven University Press: Leuven, in press. 9. Degryse, P.; Poblome, J.; Donners, K.; Deckers, S.; Waelkens, M. Geoarchaeological investigations of the “potters” quarter at Sagalassos (SW Turkey). Geoarchaeology 2003, 18 (2), 255 –281. 10. Degryse, P.; Muchez; Ph.; Six, S.; Waelkens, M. Identification of ore extraction and metal working in ancient times: a case study of Sagalassos (SW Turkey). Journal of Geochemical Exploration 2003, 77 (1), 65 –80. 11. Degryse, P.; Muchez, Ph.; Loots, L.; Vandeput, L.; Waelkens, M. The building stones of Roman Sagalassos (SW Turkey): Facies analysis and provenance. Facies 2003, 48, 9– 22. 12. Serdaru, M.; Avram, N.; Medrea, N.; Vladescu, L. Determination of trace elements content in biological materials—Measure of industrial pollution. Analytical Letters 2001, 34, 1437 –1447.
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Received January 27, 2004 Accepted June 29, 2004
