Contamination of soil and plant by recycling of scrap plastics

The present study concerns a small factory engaged in the recycling of scrap plastics by removing metals from plated surfaces with acid. The rinsing water was discharged into an old fish pond, eventually cauding fish-kills in a number of nearby fish ponds and affecting vegetable cultivations in fields on the downhill side of the factory through runoff. Ten sites were chosen to sample both the vegetation and soil for metal determination by inductively coupled plasma emission spectrophotometry. Nine sites showed various degress of contamination and the remaining one was unaffected and used as a control. The most polluted site (F8) contained 385 mg/kg Ni and 194 mg/kg Cu (total contents in soil), compared with the control site (F101) which contained 12 and 9 mg/kg of Ni and Cu, respectively. It was also noted that the metal uptake by the water spinach, Ipomoea aquatica, was significantly correlated to the contents of exchangeable metals (extracted by 1M ammonium acetate in the soil). Several grass species thriving in the polluted areas also had high concentrations of Ni and Cu, as well as other metals such as Mn, Al and Pb in their tissues. Copyright © 1989 Published by Elsevier Ltd.