摘要：A comparative pot experiment was conducted in 2014 to study heavy metal contamination in soil andbioaccumulation in leaves and roots of Spinacia oleracea (spinach) on irrigation with paper mill effluent(PME). Study revealed that there was significant increase in the content of copper (Cu, +81.62 %) at (P<1%),iron (Fe, +79.62 %), zinc (Zn, +90.73 %), cadmium (Cd, +98.99 %), lead (Pb, +95.91 %), nickel (Ni, +98.40%), chromium (Cr, +97.54 %) at (P<0.1%) in the soil irrigated with PME as compared to soil irrigated withpond water (PW) (control). Increasing PME doses from 10 % (10 % PME + 90 % PW) up to 80 % (80 %PME + 20 % PW) caused a progressive increase in the accumulation of metals, i.e. Fe, Zn, Cd, Cu, Pb, Niand Cr in the roots and leaves of S. oleracea. The metals accumulated in the plant parts (root and leaves) ofS. oleracea showed significant (p<5%) and a positive correlation with different concentrations of PME.Among various metallic concentrations high values of heavy metals such as Fe (10.97±0.02 mg/kg), Zn(8.45±0.10 mg/kg), Cd (7.63±0.08 mg/kg), Cu (12.12±0.09 mg/kg), Pb (6.47±0.04 mg/kg), Ni (8.48±0.10mg/kg), and Cr (5.81±0.02 mg/kg) were found in roots compared to Fe (9.58±0.06 mg/kg), Zn (6.68±0.06mg/kg), Cd (5.67±0.01 mg/kg), Cu (10.30±0.11 mg/kg), Pb (4.83±0.03 mg/kg), Ni (6.84±0.02 mg/kg) and Cr(4.50±0.09 mg/kg) in leaves of S. oleracea irrigated with 80 % (80 % PME + 20 % PW) dose. Thus, thepractice of using undiluted PME as agro-based organic fertilizer for irrigation increased the concentration ofheavy metals which were accumulated in S. oleracea, posing a potential threat to human health from thispractice of irrigation. Therefore, proper dilution of PME appears to be necessary for irrigation purpose for theminimum accumulation of heavy metals in soil and plants.
