Author(s):
Marques, Ana P. G. C. 
; Rangel, António O.S.S. ; Castro, Paula M. L.
Date: 2003
Persistent ID: http://hdl.handle.net/10400.14/6970
Origin: Veritati - Repositório Institucional da Universidade Católica Portuguesa
Description
The off-site migration of contaminants, when not controlled, can cause serious damage on ecossistems
and affect public health. These and other reasons bring up the need for new solutions of remediation,
to stop the dissemination of the contaminants in the environmental compartments.
Phytoremediation is an emergent technology that uses plants to remove, degradate or imobilize the
contaminants. The selection of the plant species that should be used depends mainly on it’s biomass,
it’s capacity to tolerate and bioacumulate the contaminants and on the location and characteristics of
the contamination.
The region of Estarreja is known for its strong industrial complex, composed essentially by chemical
facilities. For many years, several of these industries have discharged its solid residues in an
improvised park in the surrounding area, and conducted its wastewaters into a stream nearby (“Esteiro
de Estarreja”). Therefore, the levels of Pb, Zn, As and Hg, in the sediments of this stream, to a depth
of 50 cm, are above the limits established by EC Directive 86/278/EC - Atkins (1999). Metals pose a
specific environmental problem: they can not be destroyed, so they have to be removed and recycled.
This environmental risk cenario is aggravated by the high permeability of the soils and the intensive
agriculture in the area. Nevertheless, in the banks of the stream, the vegetation remains proliferous.
The purpose of this study is to identify plant species endemic to the site and to determine their ability
to uptake heavy metals.
Three plant species, present in a larger amount, were collected from that area and were tested for the
content of the above metals.
