
Chinese brake fern (Pteris vittata )

Water Hyacinth (Eichhornia crassipes )
Eurasian Watermilfoil (Myriophyllum spicatum)
Fool's Watercress (Apium nodiflorum)
Duckweed (Lemna trisulca L.)

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Employs phytostabilization of
pollutants
Found to phytoremediate heavy
metals, i.e. Cd, Pb
Organic phyoremediation of
petroleum (TPH)
Cultural background and
influence (marketing, aesthetics)
Profitability to existing nursery,
fertilizer, and gardening
industries
Public acceptance




Advantages: Can be used in
urban environments without
changing existing landscape.
Relatively low costs
Non-food chain plants that can
be periodically phytoextracted
for pollutants.
Can be genetically modified to
not produce pollen or set seed
with minimal effect to ecology

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
Liu et. Al tested 3 ornamentals, Impatiens Balsamina, Althaea rosea and
Candulata officinalis for ability to tolerate and accumulate Cd and Pb.
Soil and hydro conditions tested
Cd levels ranged from 0, 10, 30, 50, 100 mg/Kg-1
Pb was added to Cd in the following concentrations:
0 + 0 (control), 1 + 50, 3 + 50, 5 + 50, 10 + 50, 1 + 100, 3 + 100, 5 + 100
and 10 + 100 mg L-1
Pb(NO3)2 form of bioavailable lead
CdCl2·2.5H2O form of bioavailable cadmium
Soil





Impatiens balsamina had leaves turn brown under >50 mg/Kg
C. officinalis height increased as Cd levels increased
A. rosea height slightly decreased for levels above 50 mg/Kg
(insignificant)
C. officinalis and I. balsamina accumulates more Cd in roots than the shoot
at every Cd level
A. rosea accumulates more Cd in shoots for 10, 30, and 50 mg/Kg, but
more Cd in the roots under 100 mg/Kg CdCl2·2.5H2O




A. rosea had the highest ability to accumulate Pb, the maximal
Pb concentration in the shoots and roots was 24 and 640 mg
kg−1
Phytotoxicity shown (Cd and Pb = 10 + 50 and 10 + 100 mg L−1)
C. officinalis had the highest ability to accumulate Cd, the Cd
concentration in the shoots and roots reached 825 and 1585 mg
kg−1 in TP4 treatment, 700 and 1492 mg kg−1 in TP8 treatment,
respectively
All three plants had a lower general affinity for Pb

Case study conclusions



C. offinalis is tolerant to Cd levels, but is not a
hyperaccumulator since more Cd was found in the roots than
in the shoots. Phytostabilization
A. rosea, tolerant to heavy metals and is a hyperaccumulater of
Cd when conc. < 100 mg kg-1
Efficacy of ornamentals was examined and has potential for use
in urban environments with moderate to high Cd/Pb
contamination levels


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

Classification: Marattiales, Ophioglossales, and
leptosporangiate ferns
Best used in areas of high humidity
Ability to uptake high levels of arsenic
Industrial applications in phytoremediation
Humidity requirements reduces water necessity
Fast growing species and varieties available (increased
biomass)
Ornamental use: Japanese painted fern





Ma et al. (2001) reported the first known arsenic
hyperaccumulator Chinese brake fern (Pteris vittata L.).
Tu et al. 2002 found that P. vittata grown in an As-contaminated
soil accumulated total dry biomass of 18 g plant-1 after 18 weeks of
growth
Chinese brake fern tolerant of high concentrations of arsenic, up to
1,500 mg As kg-1 soil
Ferns operate by phytoextracting Arsenic, As(V) or As(III), storing
As in the fronds
Ferns hyperaccumulate As through phosphate transporters and
do not have phosphate deficiency symptoms at high levels of As




Contains arsenate reductase (AR) genes to reduce
arsenate to arsenite
AR was not detectable in the fronds, suggests that
arsenate reduction, occurs in roots
Arsenite is then transported to shoots, where it may be
stored in the vacuoles (Lombi et al., 2002)
75-95% As in the fronds is present in the form of
arsenite (Ma et al. 2001, Zhang et al. 2002).





10 μg As/L-1 is the limit set by US EPA
Over 29 million people in Bangladesh may be exposed
to over 50 μg/L As.
Bangladesh, India, and Pakistan have problems with
ground water contamination from As
Up to 7500 mg As/kg on a contaminated site without
showing toxicity symptoms. (Ma et al, 2001)
Contamination comes from industrial and chemical
plants, dumping effluent into groundwaters (lack of
regulation)

Hyde Park neighborhood: Augusta, GA






Low-lying geographic area containing approximately 200 houses
and surrounded by industry, abandoned industry, railroad lines and
large highways.
Problems of high poverty levels (>70%)
Abandoned houses, overgrowth of weeds, snakes, etc.
Illegal dumping and drain contamination
Lack of community cohesiveness and/or solid leadership
Phytoremedation can be used as a part of a larger objective in
urban environmental renewal




Bob Safay. ATSDR Regional Representative. U.S. EPA, Region IV
released a report in 1994.
The most serious contamination found near the Goldberg site.
From ditch sediments: Highest lead detected was 1800 mg/kg,
and the highest level of PCBs was 13.2 mg/kg
From soil samples: lead (1100 mg/kg), arsenic (59 mg/kg), and
dioxin/furans (0.0001 mg/kg
Agency for Toxic Substances and Disease Registry report,
APPENDIX 3 - MARCH 1994 HEALTH CONSULTATION

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
Perennials
Alpine Pennygrass, Thlaspi caerulescens
Hairy Goldenrod, Solidago hispida
Yellow Tuft, Alyssum lesbiacum
Bladder Campion, Silene vulgaris
Horse bean, Vicia faba
Trees and Shrubs
Aspen, Populus tremula
Shrub violet, Hybanthus floribundus
Grasses
Indian grass, Sorghastrum nutans
Kleingrass, Panicum coloratum
Little bluestem, Schizachyrium scoparius
Bent grass, Agrostis castellana



Aquatic plants are those plants living in and adapted to
aquatic environments, which can only grow in water or
permanently saturated soil.
Bodies of aquatic plants can be either floating or
submerged.
Aquatic plants are often viewed as indicators of aquatic
environment pollution.
Rivers
Lakes
Where do
they live?
Constructed Wetlands
Hydroponic systems

Inorganic pollutants




Rhizofiltration
Phytostabilization
Phytoextraction
Organic pollutants
Phytodegradation
 Phytovolatilization
 Rhizodegradation






High substrate heterogeneity
Wide application for pollutants removal and
phytoremediation
Act as a cover above contaminated areas
Rhizofiltration techniques are the most
commonly used
Pollutant removal efficiencies are significantly
related to plant species present
Pollutant Removal Efficiencies of
Constructed Wetlands
(Otte and Jacob, 2006)

Benefits:





Aesthetical functions
Provide habitat for
wildlife animal species
Educational resources
Little maintenance
required
Increased Cost-efficiency

Drawbacks:



Limited by plant tolerance
and pollutant bioavailability
Limited plant life
expectancy
Susceptible to climate
change, pollution, and
disease



Heavy metal ions of Cd2+, Hg2+, and Pb2+ are nonessential
and toxic to plants
Cu2+, Zn2+, Mn2+, Fe2+, Ni2+, and Co2+ are essential
micronutrients for plants, but toxic when present in high
concentration
Hyperaccumulators: plant species tolerate, uptake, and
translocate high levels of certain heavy metals that is toxic to
other species.

Contain >100 mg/kg of Cd, >1000 mg/kg of Cu, or >10,000 mg/kg of
Zn and Mn(dry weight in leaves)

Mercury toxicity symptoms



concentration deficits
Impaired motor function
Lead toxicity symptoms



Hg
Learning disability
Mental retardation
Chromium toxicity symptoms


Damage DNA
Damage kidney
Pb
Water Hyacinth (Eichhornia crassipes )
Eurasian Watermilfoil (Myriophyllum spicatum)
Fool's Watercress (Apium nodiflorum)
Duckweed (Lemna trisulca L.)




Floating plant with broad ,thick, and
glossy leaves that the plant body can
grow as much as 1m high.
Able to phytoaccumulate metal
pollutants contain Ag, Pb, Cd and Zn
in municipal and agricultural
wastewater.
Known as one of the plants with
fastest growth rate that can double
population in 2 weeks.
High invasive potential.



The stock solution was prepared in distilled water with analytical grade
CdCl2. 2½ H2O and ZnSO4.7H2O which was later diluted as required. The
plants were maintained in tap water with concentrations of 0.5, 1, 2, 4
mg/L of Cd and 5, 10, 20, 40 mg/L of Zn.
The test durations were 0 (two hours), 4, 8 and 12 days.
Relative growth, metal accumulation, and bioconcentration factor (BCF)
are evaluated.
Relative growth (above) and BCF (below)
Relative plant growth
Cd
Cd
Zn
(Lu et al., 2004)
Metal Accumulation
BCF
Cd
Zn
Zn




Submerged aquatic perennial plant
which grows in still or slow-moving
water.
Slender stems up to 3 m long with
numerous leaflets thread-like, 413 mm long.
Introduced to North America
between the 1950s and 1980s where it
has become invasive species.
Able to uptake and remove lead, zinc,
and copper from wastewater.
Case Study: Removal of Lead, Zinc, and Copper by Eurasian
watermilfoil




Plant tissue was washed with 3% HCl solution previously.
Metal source were provided by CuSO4, ZnSO4, and Pb(NO3)2 to
prepare the stock solutions with concentration of 2, 4, 8, 16, 32 and
64 mg/L (doubling). Standard curves were made.
Absorption tests were conducted in 250 ml conical flasks placed
on orbital shaker and contact for 2 hours.
Filtrate was analyzed by atomic absorption spectrophotometer
(AAS) to determine sample metal concentrations.
(Keskinkan et al., 2003)
According to figure 1 (left), equilibrium were reached after
about 20 mins after beginning; after that the data was adhered
well to the Langmuir equation (see below) which means that
absorption was as a monolayer.
The value of metal concentration of
solution on time t over the beginning
concentration Ct/C0 is shown below:
Compare of the metal uptake
capacities (qmax, mg/g) of
Myriophyllum spicatum to other
plant species:
(Keskinkan et al., 2003)




Hollow stems rooting at base and
finely grooved. About 0.3-1m high.
Simply pinnate leaves in shiny bright
green in color with 2-4 pairs of lobes.
Usually find in grown ditches,
shallow ponds or very damp places.
Capable to uptake and remove
various heavy metals such as Hg, Cr,
Pb, Cu, and Zn.
(Vlyssides et al., 2005)
Case Study: Removal of Copper, Lead etc. by Fool’s Watercress




A mathematical model was established to evaluate the inherent
capacity of watercress to uptake heavy metals.
Plant uptake rate follows the first order kinetic model depending
on the heavy metal concentration in the plant biomass.
This model allowed to evaluate the specific uptake rate and the
maximum content within plant biomass.
The relationship between metal concentration in solution Es
(mg/L) and plant biomass Ep (mg/g) is:
(Vlyssides et al., 2005)
Change of heavy metal concentrations in
solution and plant biomass
(Vlyssides et al., 2005)
E∞ = the saturation heavy metal
concentrations in the plant biomass
km = maximum uptake rate of metal
KS = saturation constant
(Vlyssides et al., 2005)
The estimated absorption kinetic parameters for various heavy metals, by Apium
Nodiflorum using the data acquired



Has a very simple structure that lacks
obvious stems or leaves, with small
plate-shaped structure floating on
water surface.
Reproduction is mainly rely on asexual
budding.
High pollutant removal potential due
to small size, fast growth, and easy to
cluture.
(Kara and Kara, 2004)
Case Study: Removal of Cadmium by Duckweed



The duckweed obtained from
natural lake was acclimatized
to laboratory conditions for
one week before starting
research.
Solution of Cadmium was
prepared using Cd(NO3)2 and
contact with plant sample for
different length.
After absorption, water
samples were analyzed by
AAS at 228.8nm.
Cd removal efficiencies
(Kara and Kara, 2004)

Advantages of aquatic plants



GO AQUATIC!
Faster growth and larger biomass
production rate
Relative higher capability of
pollutant uptake
Better water purification effects due
to direct contact

Advantages of terrestrial plants



More plant-soil microbe
interactions to enhance pollutant
uptake
Higher tolerance against severe
weather and temperature change
More sophisticated root system
GO TERRESTRIAL!



Ornamental phytoremediation is beautiful, profitable
and effective: utilizing phytoextraction and
phytostabilization
Ferns hyperaccumulate As which can be useful in
contaminated groundwater regions, such as Bangladesh
Hyde Park, Augusta GA has a current and ongoing
contamination problem that ornamentals may help to
alleviate without affecting food chain or food supply


Most of the aquatic plants showed high heavy metal
phytoremediation potential are usually considered as
invasive species, which indicates that there are
numerous positive aspects of those species that is able
to take advantage of
To achieve better remediate effects, more effort is
required to accelerate the pace of phytoremediation
techniques from laboratory experiment to practical use.
1. Otte, ML and Jacob, DL (2006) Constructed Wetlands for Phytoremediation. Phytoremediation Rhizoremediation 5767.
2. Kamal, M, Ghaly, AE, Mahmoud, N, Côté, R (2004) Phytoaccumulation of heavy metals by aquatic plants.
Environment International 29: 1029-1039.
3. Skinner, K, Wright, N, Porter-Goff, E (2007) Mercury uptake and accumulation by four species of aquatic plants.
Environmental Pollution 145: 234-237.
4. Titus JE and Urban RA (2009) Aquatic Plants: A General Introduction. Encyclopedia of Inland Waters 43-51.
5. Keskinkan O, Goksu MZL, Yuceer A, Basibuyuk M, Forster CF (2003) Heavy metal adsorption characteristics of a
submerged aquatic plant (Myriophyllum spicatum). Process Biochemistry 39(2): 179-183.
6. Vlyssides A, Barampouti EM, Mai S (2005) Heavy Communications in Soil Science and Plant Analysis metal removal
from water resources using the aquatic plant Apium nodiflorum. 36: 1075-1081.
7. Lu X, Kruatrachue M, Pokethitiyook P, Homyok K (2004) Removal of Cadmium and Zinc by Water Hyacinth,
Eichhornia crassipes. Science Asia 30: 93-103.
8. Kara Y, Kara I (2004) Removal of Cadmium from water using Duckweed (Lemna trisulca L.). International Journal of
Agriculture & Biology 7: 660-662.
9. Duan G, Zhu Y, Tong Y, Cai C, Kneer R (2005) Characterization of arsenate reductase in the extract of roots and
fronds of Chinese brake fern, an arsenic hyperaccumulator. Plant Physiology 138, 461-469
10. Ma, L.Q., K.M. Komar, C. Tu, W. Zhang,and Y Cai. 2001. A fern that hyperaccumulates arsenic. Nature. 409:579.
11. Internet source, Banglopedia.org http://www.banglapedia.org/httpdocs/HT/A_0308.HTM
12.Internet source, Slide 15. http://www.hamitekllc.com/sites/mountainmovers.org/files/img/arsenicpoisoning.gif
13. Tu, C., L.Q. Ma, A.O. Fayiga and EJ Zillioux. (2004) Phytoremediation of Arsenic-Contaminated Groundwater by
the Arsenic Hyperaccumulating Fern Pteris vittata L . International Journal of Phytoremediation, 6(1):35–47.
14. Internet source, Slide 3(b). http://www.types-of-flowers.org/pictures/alcea_rosea.jpg
15. Internet source, Slide 3(a). http://pics.davesgarden.com/pics/2009/03/02/purplesun/ed602b.jpg
16. Hyde Park Charettte Report. October 2008. The University of Georgia College of Environment and Design Center
for Community Design and Preservation. www.ced.uga.edu/charrettes.html
17. Rathinasabapathi, Bali, L.Q. Ma and M Srivastava. (2006) Floriculture, Ornamental and Plant Biotechnology
Volume III. Global Science Books, UK.
18. Tu C, Ma LQ (2005) Effects of arsenic on concentration and distribution of nutrients in the fronds of the arsenic
hyperaccumulator Pteris vittata L. Environmental Pollution. 135, 333-340.
19. Internet source, slide 11(b). http://www.shadesofgreenusa.com/Priclist_files/painted_fern1.jpg
20. J. Liu, Q. Zhou, T. Sun, L.Q. Ma and S. Wang. (2008) Identification and Chemical Enhancement of Two
Ornamental Plants for Phytoremediation. Bull Environ Contam Toxicol 80:260–265.
21. J. Liu, Q. Zhou, T. Sun, L.Q. Ma and S. Wang. (2008) Journal of Hazardous Materials 151:261–267.
22. Fiegl, J., Bryan P. McDonnell, Jill A. Kostel, Mary E. Finster, and Dr. Kimberly Gray "A Resource Guide: The
Phytoremediation of Lead to Urban, Residential Soils".
http://www.civil.northwestern.edu/EHE/HTML_KAG/Kimweb/MEOP/INDEX.HTM
23. Lombi E., F. Zhao, M. Furhrmann, S.Q. Ma and S. McGrath. (2002) Arsenic distribution and speciation in the
fronds of the hyperaccumulator Pteris vittata. New Phytologist. 156: 195–203.
24. Zhang WH, Cai Y, Tu C, Ma LQ. (2002) Arsenic speciation and distribution in an arsenic hyper accumulating
plant. Sci Total Environ.; 300(1-3):167–177.
25. Zhao FJ, Dunham SJ, McGrath SP. Arsenic hyper accumulation by different fern species. New Phytologist.
2002;156(1):27–31.
26. I. Alkorta, J. Hernández-Allica, and C. Garbisu (2004) Environment International. 30: 7, 949-951.
27. Safey, Bob. Agency for Toxic Substances and Disease Registry. (1994)Appendix 3 – March 1994 Health
Consultation. http://www.atsdr.cdc.gov/HAC/pha/pha.asp?docid=1029&pg=6
Suggested reading material
Checker, Mellissa. (2005) From Friend to Foe and Back Again: Industry and environmental action in the urban south
http://www.augustaneeds.com/files/ASU_HydePark_MelissaChecker_2005.pdf
Checker, Mesllisa (2005) Polluted Promises: Environmental Racism and the Search for Justice in a Southern Town.
NYU Press, NewYork, NY.