Heavy metal accumulation in the bark and leaves of Juglans regia planted in Artvin City, Turkey

The aim of this study was to determine the level of heavy metals such as copper, iron, manganese, zinc, lead, nickel, cadmium and chromium concentrated in Juglans regia bark and leaf samples from different localities in Artvin, Turkey. Analysis of the heavy metals Cu, Fe, Mn, Zn, Pb, Ni, Cd and Cr in samples was carried out by inductively coupled plasma optical emission spectroscopy (ICP–OES; Perkin Elmer, Optima 8000 DV). Statistical significance was determined by analysis of variance (ANOVA). The comparisons were performed in order to determine whether there were any differences between J. regia bark and leaf samples in terms of average heavy metal accumulation levels. As a result of this study, the following mean concentrations were determined for J. regia bark samples: the contents of Cu, Fe, Mn, Zn, Pb, Ni, Cd and Cr (μg g(−1), dry weight) ranged from 72.46 to 88.14, 14.40 to 628.0, 0.896 to 67.71, 7.000 to 28.52, 0.040 to 0.905, 1.031 to 2.744, 0.011 to 0.158 and 1.192 to 3.134, respectively. On the other hand, for J. regia leaf samples, the contents of Cu, Fe, Mn, Zn, Pb, Ni, Cd and Cr (μg g(−1), dry weight) ranged from 0.339 to 13.80, 12.72 to 698.2, 1.001 to 204.6, 7.362 to 56.03, 0.158 to 0.665, 0.130 to 2.744, 0.041 to 0.114 and 0.508 to 2.767, respectively. In the statistical analysis, heavy metal accumulation values of J. regia bark and leaf samples for Cu, Ni and Cr were significantly different (P < 0.05).