title: Pb and Zn imaging and in situ speciation at the geogenic/biogenic interface in sentinel earthworms using electron microprobe and synchrotron micro-focus X-ray spectroscopy.
abstract: Using synchrotron- and electron microscope-based X-ray microanalyses, the distribution and speciation of Zn and Pb were examined in situ in two earthworm species (Dendrodrilus rubidus and Lumbricus rubellus) living in heavily-polluted soils.
  
  
  RESULTS
  (i) Zn spectra in ingested soil and in tissues more closely resembled Zn(3)(PO(4))(2) than ZnS; (ii) Zn speciation in tissues gave a best fit for Zn to the inner shell of 4 oxygens at 1.94 Å (or nitrogens at 1.96 Å); (iii) the best fit for Pb in tissue was with a shell of oxygens at 2.18 Å and a shell of sulphurs at 2.67 Å; (iv) a component of the Zn and much of the Pb detectable in gut contents was co-distributed with S; (v) Zn and Pb display 'soft' acid affinities in soil, but 'hard' acid affinities in tissue. This is the first metal characterisation study conducted on an invertebrate quench-frozen in the field.
authors.affiliation: Cardiff School of Biosciences, Cardiff University, Park Place, Cardiff CF10 3US, Wales, UK. morganaj1@cardiff.ac.uk
authors.forename: A J
authors.initials: AJ
authors.lastname: Morgan
authors.forename: P
authors.initials: P
authors.lastname: Kille
authors.forename: A
authors.initials: A
authors.lastname: Bennett
authors.forename: M
authors.initials: M
authors.lastname: O'Reilly
authors.forename: P
authors.initials: P
authors.lastname: Fisher
authors.forename: J M
authors.initials: JM
authors.lastname: Charnock
mesh_terms: D000818:Animals; D004577:Electron Probe Microanalysis; D004784:Environmental Monitoring / Q000379:methods*; D007854:Lead / Q000032:analysis* / Q000737:chemistry; D009835:Oligochaeta / Q000737:chemistry*; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis* / Q000737:chemistry; D017356:Synchrotrons; D015032:Zinc / Q000032:analysis* / Q000737:chemistry
chemical_list: D012987:Soil; D012989:Soil Pollutants; D007854:Lead; D015032:Zinc