Evaluating metal accumulation in lichens.The Romanian experience

A.-M. RUSU, O.W. PURVIS

Natural History Museum, Cromwell Rd., London SW7 5BD, UK

(a.rusu@nhm.ac.uk; w.purvis@nhm.ac.uk)

Multi-element composition of lichens and other environmentalsamples are being evaluated. Rare earth elements (REE) andother rare elements are increasingly involved in industrial process-es and released into the environment. Their fate and impact onecosystems are largely unknown. Understanding metal fixationand release by lichens and the origin of elements is important torefine biomonitoring protocols and to understand the influenceof metals (from both natural and anthropogenic sources) on bio-diversity. The aim of the present investigation is to compare mul-ti-element including rare earth element composition of lichenswith those of bark, soil, waste and ore materials.

Point sources, nowadays very rare in many formerly industria-lised regions are natural laboratories to investigate the effects ofpollutants and geology on vegetation. One such is Zlatna town,one of the top 10 pollution hotspots in Romania. Followingsmelter closure in May 2004, extensive mine tailings, slag dumpsand waste heaps remain. Lichens were transplanted across a tran-sect established in May 2004 centred on a large metallurgicalwaste dump in Zlatna.

Lichen and bark multi-element compositions were most similarreflecting fixation of elements of environmental concern and theability for tree canopies to concentrate substances leading toenhanced deposition to both lichens and bark. Multi-elementanalysis supports the view that epiphytic lichens, unlike trees,are not influenced by lower groundwater, and are excellent indica-tors for REE and other rare elements entering the surface envi-ronment, difficult to detect by conventional means.

ReferencesRusu, A.-M., Jones, G.C., Chimonides, P.D.J., Purvis, O.W., 2006.

Environ. Pollut. 143, 81–88. doi:10.1016/j.envpol.2005.11.002.Rusu, A.-M., Chimonides, P.D.J., Jones, G.C., Garcia-Sanchez, R.,

Purvis, O.W., Environ. Sci. Technol., submitted for publication.

doi:10.1016/j.gca.2006.06.1013

SEM-EDX analysis of particulate matteron sticky pads and lichens immediately

following closure of a Cu smelterin Romania

A.-M. RUSU, B.J. WILLIAMSON, O.W. PURVIS

Natural History Museum, Cromwell Rd., London SW7 5BD, UK

(a.rusu@nhm.ac.uk; b.williamson@nhm.ac.uk; w.purvis@

nhm.ac.uk)

Particulate matter deposition is being compared on sticky padsand Hypogymnia physodes lichen transplants exposed over a3-month period along a 40 km transect centred on Zlatna, inthe Romanian Apuseni Mountains (Rusu et al., 2006; Rusuet al., submitted). The extent to which lichen metal concentrationsreflect quantifiable deposition levels for different elements andphysicochemical forms is controversial. This research is anecessary first step towards refining lichen biomonitoringprotocols.This study aims (1) to identify the mineralogy andorigin of particles on the surfaces of sticky pads and on Hypogym-

nia thalli (2) to examine the relationship between particulatecapture on sticky pad surfaces and on H. thalli.

As far as we are aware this is the first study investigating par-ticles on sticky pads in relation to those on lichens and other envi-ronmental samples using advanced SEM/microsocopicalanalytical techniques immediately following the closure of amajor pollution source. This ‘natural experiment’ is centred ona large mine waste tailing close to Zlatna town centre two weeksfollowing closure of an ore-processing plant and smelter and isdeveloped from a study carried out in the Russian Urals duringoperation of a major copper smelter (Williamson et al., 2004).

Particle chemical composition, size and shape are being quan-tified using automatic imaging software and compared with multi-element composition data obtained by ICP-AES and ICP-MS.

ReferencesRusu, A.-M., Jones, G.C., Chimonides, P.D.J., Purvis, O.W., 2006.

Environ. Pollut. 143, 81–88. doi:10.1016/j.envpol.2005.11.002.Rusu, A.-M., Chimonides, P.D.J., Jones, G.C., Garcia-Sanchez, R.,

Purvis, O.W., Environ. Sci. Technol., submitted for publication.Williamson, B.J., Mikhailova, I., Purvis, O.W., Udachin, V., 2004. Sci.

Total Environ. 322, 139–154.

doi:10.1016/j.gca.2006.06.1014

Goldschmidt Conference Abstracts 2006 A549