Nickel and chromium concentrations in Italian ryegrass exposed to ambient air in urban, suburban and rural areas

Nickel and chromium accumulation from the air in Italian ryegrass (Lolium multiflorum L.) is presented in this paper. Plants were exposed at five sites varying in environmental characteristics. Four one-month series were performed during the 2011 and 2012 growing seasons. Chromium and nickel concentrations in leaves were analysed after every series and compared to control plants. The lowest levels of both trace elements were found in samples collected from control sites. Canonical variate analysis revealed differences among sites and the control, and on this basis we found the lowest values in the suburban area. The lowest trace element concentrations of Cr in leaves were observed at the beginning of the growing season and the highest from mid-June to mid-August, while Ni concentrations varied among series and years. Accumulation of both trace elements in Italian ryegrass was at a comparable level or lower than results obtained in similar investigations in other countries. Moreover, the higher concentrations of both elements were probably connected with increased traffic and elevated small industry activities in urban and rural areas.