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International Conference on

Recent Trends in Environmental Sustainability

ESCON22/ETERM/05
A review of metal hyper-accumulator plant species for reducing environmental toxicity
and improving environmental cleanup

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Imran Hashmi , Javeria Iqbal Malik , Syeda Hira Noor
1 Institute of Environmental Sciences and Engineering (IESE), School of Civil and
Environmental Engineering (SCEE), National University of Sciences and Technology
(NUST), H-12 Islamabad, Pakistan
Correspondence: imranhashmi@iese.nust.edu.pk
Abstract
Toxic heavy metal pollution is a universal environmental concern. It can lead to contamination
of soil thus can pose a serious threat to the whole biosphere. When a site is contaminated by
chemical, physical and biological alterations of soil, surface water and ground water that it
becomes alarming for public health and environment. Using plants for pollutant removal i.e.
phytoremediation is a globally renowned technique that has an ultimate lower cost.
Contamination of soils has been on rise due to intense agronomic and industrial activities.
Heavy metals accumulated in the soil are toxic and cannot be biodegraded, hence, soils need
to be remediated (Leung, 2013). The high costs and inefficiency render the traditional
methods, like excavation, for soil treatment ineffective. Phytoremediation has a great potential
in terms of cleaning contaminants that are covering a large area and are near the surface. It is
also very environment friendly (Bini, 2010). Hyper accumulation is referred as uptake of
metals from the soil at 50 to 100 times higher rates than in non-accumulating plants (Maestri,
Marmiroli, Visioli, & Marmiroli, 2010). Hyper-accumulation can be estimated using
translocation factor, bioaccumulation coefficient and bio-concentration factor. This review
gives a complete data base of about 100 metal hyper-accumulating plant species.
Acanthaceae, Asteraceae, Balsaminaceae, Poaceae, Fabaceae, Brassicaceae, Cruciferae,
Convolvulaceae, Amaranthaceae, Turneraceae, Verbenaceae are some plant families which
are better at hyper-accumulaters of various heavy metals dominantly zinc, cadmium, cobalt,
nickel, copper and lead (van der Ent et al., 2019, Chaney & Baklanov, 2017, Malaisse et al.,
2015, and Phaenark et al., 2009).

Keywords: Heavy metal; Hyper accumulation; Phyto-remediation; Toxicity

Department of Environmental Sciences, COMSATS University Islamabad, Vehari Campus

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