DOI : 10. 1051/jp4 : 20030272 Ultrastructural changes, phenolics localization and heavy metals distribution in the leaf of Vaccinium myrtillus L. exposed to chromium in environment-preliminary observations D. Bialonska, K. Sawicka-Kapusta, A. Obel', M. Kuras2, T. Tykarska2 and P. Banas Department of Environmental Monitoring, Institute of Environmental Sciences, Jagiellonian University, 6 Ingardena St., 30-060 Cracow, Poland 1 Department of Chemistry, Spectroscopy Institute, Trent University, Peterborough, ON, K9J 7B8, Canada 2 Depaffment of Plant Morphogenesis, Warsaw University, 1 Miecznikowa St., 02-096 Warsaw, Poland Abstract. Leaves of laccinium mvrtillus L. were collected from the forest site illfluenccd bv emission. containing chromium compounds in lùgli amounts. from the chemical industry " Alwemia ", located 20 km west of Krakow (land). As the control area the forest 10 km west of studied site was chosen. Three compartments of the leaf were distinguished : e surface, when wax together with embedded elements were removcd by procedure of dipping in almost boiling water Ll l inside the tissue but free ions, by extraction in 20% ethanol + 1% acetic acid [2]. ~ bound ions, which could bc removed only by analysis of'leftover tissues'. Oiromium and other élément (Cu, Zn. Fe) levels were analysed by atomic absorption spectrometry. in cach of studied ieaf compartments-to estabtish their possible interactions and localisation. Transmission Electron Microscopy revealed disturbances in cell organelle structures. Additionally with the histochemical method we localised phenolic compounds in the celL considering their involvement in heavy metals detoxification l. INTRODUCTION Due to some kind of chemical industry processes large quantities, of chromium compounds are emitted into the environment and can have significant biological and ecological effects [3]. Chromium plays essential role in biological life, but when accumulated above the critical level it induces toxic effects in plants (e. g. DNA breakage, enzyme inhibition, cellular reduction), resulting in reduced root and shoot growth, chlorosis, stunting and finally plant death [4]. Chromium like other heavy metals (Cd, Zn, Ni, Mn) in toxic doses may cause ultrastructural changes in the cell [5]. However, not many papers referred to this subject consider plants growing in natural environment contaminated with chromium. Plant phenolics (organic substances which are aromatic compounds with hydroxyl substituents), constitute a group of natural products of structural diversity and wide phylogenetic distribution, of which the precise physiological function is unknown [6]. However, their synthesis was observed to increase due to stress of abiotic factors, such as e. g. heavy metals [7]. The aim of presented study was to assess the influence of high amounts of chromium in the forest ecosystem on the leaf ultrastructure, heavy metals distribution and phenolic localisation in Vaccínium myrtillus L-an important species in the forest undergrowth. 2. MATERIALS AND METHODS The study area (1 ha) was located in the neighbourhood of the chemical industry " Alwernia " (20 km west of Krakow, Poland) characterised by high emission of chromium compounds. As the control area the forest 10 km west of Alwemia was chosen. Leaves of t'occMMm m'rKA'L. were coiiected from 6 randomly chosen points in each of the two investigated on the June 2002. Regarding that om studies refer to the ieaf surfaces, the important was the lack of the rain for at least 3 previous days. Three compartments of the leaf were distinguished :