Investigation of the potential of several plants for phytoremediation of nickel contaminated soils and for nickel phytoextraction

A. Cullaj1, A. Hasko2, F. Kongoli3,*

1 Department of Chemistry, University of Tirana, Tirana, Albania
2 Department of Agronomy, Agricultural University of Tirana, Tirana, Albania
3 FLOGEN Technologies Inc., 5757 Decelles Ave., Suite 511, Montreal, Quebec, H3V 1G5 Canada

Received 15 May 2003; accepted 15 March 2004


Several industrial sites suffer from the contamination of soils from heavy metals, which are emitted among others by anthropogenic mining and metallurgical activities. Effective and economic physicochemical technologies for remediation of these sites remain complicated and costly. A new alternative remediation technique is the so-called phytoremediation. This is based on the ability of some plants to accumulate very high concentrations of metals from soils and thus providing the basis for a remediation of the contaminated sites. This technique as an emerging branch of natural biotechnology, has several advantages compared to the sophisticated physicochemical techniques of soil remediation. It is not only environmentally friendly but also its costs are quite low since it is solar driven. Furthermore plants can accumulate metals to such levels that the mineral recovery maybe feasible even in conventional Ni refinery or smelting operations.

In this work, the potential of many plants to accumulate nickel has been investigated in order to identify the species which offer the best phytoremedial potential for nickel contaminated soils in Albania. Field surveys have been made in five nickel-containing sites in order to identify the nickel tolerant species that have spontaneously grown in contaminated soils. Atomic Absorption Spectrometry measurements were carried out on 145 different plants collected. 16 of them were identified as having an hyper ability to accumulate nickel since they contained more than 10 000mg Ni per kg (DW). Seven taxa are of Alyssum genus and one of Bornmuellera genus of Cruciferae. The highest accumulation of nickel was present in aerial parts of Alyssum murale var. chlorocarpum Hausskn (25 500mg/kg or 2.5%) and Alyssum markgrafii O.E. Schulz (23 700mg/kg or 2.37%). The seeds germinated are more evidenced at A.m. var. chlorocarpum, about 63%. These plants are suggested as the most promising species to be used for phytoremediation purposes in nickel contaminated soils and phytoextraction of nickel.

Keywords: Contaminated soils; Phytoremediation; Phytoextraction; Nickel; Alyssum

* Corresponding author
   E-mail : fkongoli@flogen.com