Table 2: Percentage of elements detected and Ca/P ratio in superficial, intermediate and medial layers of dugong tusks.

From: Elemental classification of the tusks of dugong (Dugong dugong) by HH-XRF analysis and comparison with other species

Ele.SuperficialIntermediateMedialp-value
Al0.203 ± 0.061a1.337 ± 0.275b1.873 ± 0.215c0.027
Si2.125 ± 1.457a0.416 ± 0.213b0.347 ± 0.220b0.000
P7.393 ± 1.137a3.252 ± 1.637b3.601 ± 1.691b0.000
S0.203 ± 0.113a0.282 ± 0.076b0.275 ± 0.086b0.014
ClN.D.2.741 ± 1.1842.597 ±  ± 0.5320.124
KN.D.0.194 ± 0.1260.123 ± 0.0520.850
Ca22.137 ± 2.142a14.215 ± 3.466b15.324 ± 2.594b0.000
Ti0.045 ± 0.015a0.032 ± 0.007b0.031 ± 0.006b0.000
V0.018 ± 0.003a0.015 ± 0.003b0.016 ± 0.004a,b0.029
Cr0.009 ± 0.002a0.008 ± 0.002a,b0.008 ± 0.001b0.024
Mn0.008 ± 0.002a0.006 ± 0.001b0.007 ± 0.001b0.000
Fe0.039 ± 0.031a0.016 ± 0.003b0.017 ± 0.005b0.000
Ni0.002 ± 0.0000.003 ± 0.0070.002 ± 0.0000.338
Cu0.005 ± 0.0070.003 ± 0.0020.002 ± 0.0000.778
Zn0.037 ± 0.009a0.013 ± 0.003b0.014 ± 0.004c0.000
Zr0.013 ± 0.0020.013 ± 0.0020.014 ± 0.0040.601
Ag0.016 ± 0.002a0.014 ± 0.002b0.015 ± 0.001b0.004
Cd0.021 ± 0.003a0.019 ± 0.002b0.020 ± 0.002b0.001
Sn0.024 ± 0.004a0.023 ± 0.002b0.022 ± 0.002b0.008
Sb0.031 ± 0.005a0.030 ± 0.002a,b0.030 ± 0.003b0.037
W0.003 ± 0.000N.D.N.D.N.A.
Pb0.001 ± 0.001N.D.N.D.N.A.
LE67.857 ± 3.436a80.452 ± 3.726b79.217 ± 3.724b0.000
Ca/P3.051 ± 0.359a5.049 ± 1.931b5.049 ± 1.931b0.000
  1. Bold numbers indicate significantly higher values. N.D. = not detected, N.A. = not analyzed. Al = aluminum, Si = silicon, P = phosphorus, S = sulfur, Cl = chlorine, K = potassium, Ca = calcium, Ti = titanium, V = vanadium, Cr = chromium, Mn = manganese, Fe = iron, Ni = nickel, Cu = copper, Zn = zinc, Zr = zirconium, Ag = silver, Cd = cadmium, Sn = tin, Sb = antimony, W = tungsten, Pb = lead, LE = light elements. a,b,cIndicate a significant difference at p < 0.05 when compared in the different layers of dugong tusks