Internal elements of the millipede, Chamberlinius hualienensis Wang (Polydesmida: Paradoxosomatidae)

Abstract

The concentrations of 54 elements of the millipede Chamberlinius hualienensis and the soil including leaf litters were examined using inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS). In all the millipedes, the Ca concentration derived from the calcium carbonate in the exoskeleton was the highest, at an average of 76 μg/mg-weight, and the other major elements were the following: Mg, K, Na, Fe, Al, Cu, Zn, Sr, Ba, Mn and Ti (>1 ng/mg-weight), whereas Ni, Cr, V, Ga, Mo, Co, Cd, etc. were at trace levels. Interestingly, the contents of Ca, Mg, K, Na, Zn, Sr, V, Co, Ag, and Sc in larvae were higher than in adult millipedes. Although the heavy metal contents, in the order of Cu>Pb>Cd, were similar to those of other invertebrates such as chilopoda, collembola, and carabidae, there was a high concentration of Cu in the millipedes. The other internal metals, As and Ag, were dependent on the soil concentrations in the habitat. Zn concentrations at sampling sites were different, but a constant level was maintained in the millipede. The results suggest that millipedes may provide information on the accumulation or regulation mechanism in the body for certain hazardous heavy metals. The C1 chondrite normalization pattern for lanthanoid series elements in both the millipede and soil indicated that the environmental habitats were well protected from pollution. The characteristics of internal elements and metal accumulation in the millipede in terms of relation to the habitat would be useful information for environmental pollution studies.