United States
Environmental Protection
Agency
Solid Waste and
Emergency Response
(5102G)
EPA 542-B-99-003
June 1999
www.epa.gov/tio
clu-in.org
4ปEPA
Phytoremediation Resource
Guide
Transpiration
Degradation
Fixation
Uptake
-------
-------
EPA 542-B-99-003
June 1999
Phytoremediation Resource Guide
U.S. Environmental Protection Agency
Office of Solid Waste and Emergency Response
Technology Innovation Office
Washington, DC 20460
-------
Notice
This resource guide was prepared by: Environmental Management Support, Inc., 8601 Georgia
Avenue, Suite 500, Silver Spring, MD 20910 under contract 68-W6-0014, work assignments 73 and
94, with the U.S. Environmental Protection Agency. Mention of trade names or commercial products
does not constitute endorsement or recommendation for use. For more information about this project
contact: Dawn Carroll, U.S. Environmental Protection Agency (5102G), Technology Innovation Office,
401 M Street, SW, Washington, DC 20460, 703-603-1234, e-mail: carroll.dawn@epa.gov.
-------
FOREWORD
Identifying and accessing pertinent information resources that will help site cleanup managers evaluate
innovative technologies is key to the broader use of these technologies. This Guide is intended to
increase awareness about technical information and specialized resources related to phytoremediation
technologies.
Specifically, this document identifies a cross section of information intended to aid users in remedial
decision-making, including abstracts of field demonstrations, research documents, and information to
assist in the ordering of publications. In addition, the look-up format of this document allows the user
to quickly scan available resources and access more detailed abstracts.
Please let us know about additional information that could make this Guide (and others in the series)
more useful to you. This and the other reports listed below are available to the public from the
Technology Innovation Office Home Page: http://www.epa.gov/tio.
Bioremediation Resource Guide
Groundwater Treatment Technology Resource Guide
Physical/Chemical Treatment Technology Resource Guide
Soil Vapor Extraction (SVE) Enhancement Technology Resource Guide
Soil Vapor Extraction Treatment Technology Resource Guide
-------
TABLE OF CONTENTS
INTRODUCTION iii
HOW TO USE THIS GUIDE v
HOW TO ORDER DOCUMENTS LISTED IN THIS GUIDE vi
TECHNOLOGY SUMMARY AND MATRIX vii
ABSTRACTS OF PHYTOREMEDIATION RESOURCES 1
General Information 1
Publications Containing Multiple Papers 6
Organic Contaminants 7
Overviews 7
Field Studies and Demonstrations 8
Research 11
Publications Containing Multiple Papers 18
Inorganic Contaminants 18
Overviews 18
Field Studies and Demonstrations 20
Research 20
Publications Containing Multiple Papers 27
Internet Resources 27
-------
INTRODUCTION
EPA is committed to identifying the most effective and efficient means of addressing the thousands of
hazardous waste sites in the United States. Therefore, the Office of Solid Waste and Emergency
Response's (OSWER's) Technology Innovation Office (TIO) is working in conjunction with the EPA
Regions and research centers and with industry to identify and encourage the further development and
implementation of innovative treatment technologies.
One way to encourage the use of these technologies is to ensure that decision-makers are aware of the
most current information on technologies, policies, and other sources of assistance. This Guide was
prepared to help identify documents that can directly assist Federal and State site managers,
contractors, and others responsible for the evaluation of technologies. Specifically, this Guide is
designed to help those responsible for the remediation of RCRA, UST, and CERCLA sites that may
employ phytoremediation technologies.
This Guide provides abstracts of over 100 phytoremediation overviews, field studies and
demonstrations, research articles, and Internet resources. It also provides a brief summary of
phytoremediation. Finally, a matrix is also provided to allow easy screening of the abstracted
references.
To develop this Guide, a literature search using relevant terms was conducted on a variety of
commercial and Federal databases including:
National Technical Information Service (NTIS)
Energy Science and Technology
Enviroline
Water Resources Abstracts
Pollution Abstracts.
In addition, Internet resources yielded numerous citations. These Internet resources include:
U.S. Environmental Protection Agency
http://www. epa. gov
U.S. Army Corps of Engineers Phytoremediation Research
http://www. wes. army. mil/EL/phyto
U.S. Army Environmental Center
http://aec-www. apgea. army, mil: 8080
Air Force Center for Environmental Excellence
http://www. afcee. brooks, af.mil
U. S. Department of Energy
http://www. doe. gov
U. S. Department of Agriculture
http://www. usda.gov
The Hazardous Waste Clean-Up Information Home Page
http: //clu-in. org
The Ground Water Remediation Technologies Analysis Center
http://www. gwrtac. org
in
-------
The Remediation Technologies Development Forum
http://www. rtdf.org
The Great Plains/Rocky Mountain Hazardous Substance Research Center
http://www. engg. ksu. edu/HSRC
The Phytoremediation Electronic Newsgroup Network
http://www. dsa. unipr. it/phytonet
The Interstate Technology and Regulatory Cooperation Working Group
http://www. sso. org/ecos/itrc
Battelle
http://www. battelle. org
The selected references are not an exhaustive list of all available literature, but rather a representative
sample of available print and Internet resources. For a more extensive list of phytoremediation
resources, visit the Remediation Technologies Development Forum, Phytoremediation of Organics
Action Team's Home Page at http://www.rtdf.org/public/phyto. The Remediation Technologies
Development Forum is a public-private partnership operated by the U.S. Environmental Protection
Agency. The Phytoremediation of Organics Action Team includes representatives from industry and
government who share an interest in further developing and evaluating the use of plants and trees to
remediate contaminated soil and water. The Action Team has compiled a bibliography containing over
1,400 citations of peer-reviewed journal articles, presentations and posters from conferences, book
chapters, and articles from newspapers and magazines. The bibliography may be viewed or searched
online.
Due to the inherent lag time between document publication and subsequent listing in electronic
databases, there may be more recent references available than those included in the Guide. Most of the
references in the Guide are of documents published between 1994 and 1998. The documents selected
are available from suppliers such as EPA's National Service Center for Environmental Publications, the
National Technical Information Service, document delivery services, and a variety of libraries.
Descriptions of specific technologies and methodologies in this Guide does not represent an
endorsement by EPA.
IV
-------
How TO USE THIS GUIDE
When using this Guide to identify resource information on phytoremediation technologies, you may
wish to take the following steps:
1. Turn to the Phytoremediation Resource Matrix located on pages ix through xxii of this Guide.
This matrix lists all abstracted resources alphabetically by document type, identifies the type of
information provided by each document, and provides a document ordering number when
available. Documents in the matrix are divided into the following topical categories: general
information, organic contaminants, inorganic contaminants, and Internet resources.
2. Select the documents that appear to fit your needs based on the information in the matrix.
3. Check the page number provided in the matrix. This refers to the page number of the document
abstract in the Guide.
4. Review the abstract that corresponds to the document in which you are interested to confirm that
the document will fit your needs.
5. If the document appears to be appropriate, note the document number highlighted under the
abstract. For example:
EPA Document Number: EPA 542-R-97-004
[Note: Some documents do not have ordering numbers. These documents can be obtained through
local, technical, or university libraries.]
6. Turn to the section entitled "How to Order Documents Listed in this Guide" on page vi of this
Guide and order your document using the directions provided.
-------
How TO ORDER DOCUMENTS LISTED IN THIS GUIDE
Documents listed in this Guide are available through a variety of sources. When ordering documents
listed in the Abstracts section of this Guide, use the number listed in the bar below the document title,
or refer to the source indicated as part of the citation. If using the Phytoremediation Resource
Matrix, use the page number listed with the document title to refer to the complete citation and
abstract. EPA 542 documents may be obtained through the National Service Center for Environmental
Publications (NSCEP), and EPA 530 documents may be obtained from the RCRA Information Center
(RIC). These document repositories provide in-stock documents free of charge, but document supplies
may be limited. Documents obtained through the National Technical Information Service (NTIS) are
available for a fee; therefore, prior to purchasing a document through NTIS, you may wish to review a
copy at a technical or university library, or a public library that houses government documents.
Document Type
Publication numbers with the following prefixes:
AD
DE
PB
Document Source
National Technical Information Service (NTIS)
5285 Port Royal Road
Springfield, VA 22161
Tel: 1-800-553-NTIS
Fax: (703) 605-6900
Internet: http://www.ntis.gov/
NTIS provides documents for a fee.
Publications numbers beginning with:
EPA 542
National Service Center for Environmental
Publications (NSCEP)
P.O. Box 42419
Cincinnati, OH 45242-2419
Tel: 1-800-490-9198
Fax:(513)489-8695
Internet: http://www.epa.gov/ncepihom/
A document title or number is needed to place an order with NSCEP.
Some out-of-stock documents may be purchased from NTIS.
Publications numbers beginning with:
EPA 530
RCRA Information Center (RIC)
401 M St., SW Mailcode: 5305
Washington, DC 20460
Tel: (703) 603-9230
Fax: (703) 603-9234
Internet: http://www.epa.gov/epaoswer/general/
ricorder.htm
VI
-------
TECHNOLOGY SUMMARY
Phytoremediation is the direct use of living plants for in situ remediation of contaminated soil, sludges,
sediments, and ground water through contaminant removal, degradation, or containment. Growing and,
in some cases, harvesting plants on a contaminated site as a remediation method is an aesthetically
pleasing, solar-energy driven, passive technique that can be used to clean up sites with shallow, low to
moderate levels of contamination. This technique can be used along with or, in some cases, in place of
mechanical cleanup methods. Phytoremediation can be used to clean up metals, pesticides, solvents,
explosives, crude oil, polycyclic aromatic hydrocarbons, and landfill leachates.
Phytoremediation has been studied extensively in research and small-scale demonstrations, but full-
scale applications are currently limited in number. Further development and research of the
mechanisms described below likely will lead to wider acceptance and use of phytoremediation.
Phytoremediation is a general term for several ways in which plants are used to remediate sites by
removing pollutants from soil and water. Plants can degrade organic pollutants or contain and stabilize
metal contaminants by acting as filters or traps. Some of the methods that are being tested are described
below.
Phytoextraction
Rhizofiltration
Phytostabilization
Phytoextraction, also called phytoaccumulation, refers to the uptake and
translocation of metal contaminants in the soil by plant roots into the
aboveground portions of the plants. Certain plants called hyperaccumulators
absorb unusually large amounts of metals in comparison to other plants. One or
a combination of these plants is selected and planted at a site based on the type
of metals present and other site conditions. After the plants have been allowed
to grow for several weeks or months, they are harvested and either incinerated
or composted to recycle the metals. This procedure may be repeated as
necessary to bring soil contaminant levels down to allowable limits. If plants
are incinerated, the ash must be disposed of in a hazardous waste landfill, but
the volume of ash will be less than 10% of the volume that would be created if
the contaminated soil itself were dug up for treatment.
Rhizofiltration is the adsorption or precipitation onto plant roots or absorption
into the roots of contaminants that are in solution surrounding the root zone.
The plants to be used for cleanup are raised in greenhouses with their roots in
water rather than in soil. To acclimate the plants once a large root system has
been developed, contaminated water is collected from a waste site and brought
to the plants where it is substituted for their water source. The plants are then
planted in the contaminated area where the roots take up the water and the
contaminants along with it. As the roots become saturated with contaminants,
they are harvested and either incinerated or composted to recycle the
contaminants.
Phytostabilization is the use of certain plant species to immobilize contaminants
in the soil and ground water through absorption and accumulation by roots,
vn
-------
Phytodegradation
adsorption onto roots, or precipitation within the root zone. This process
reduces the mobility of the contaminant and prevents migration to the ground
water or air, and it reduces bioavailability for entry into the food chain. This
technique can be used to reestablish a vegetative cover at sites where natural
vegetation is lacking due to high metal concentrations in surface soils or
physical disturbances to surficial materials. Metal-tolerant species can be used
to restore vegetation to the sites, thereby decreasing the potential migration of
contamination through wind erosion, transport of exposed surface soils, and
leaching of soil contamination to ground water.
Phytodegradation, also called phytotransformation, is the breakdown of
contaminants taken up by plants through metabolic processes within the plant,
or the breakdown of contaminants external to the plant through the effect of
compounds (such as enzymes) produced by the plants. Pollutants are degraded,
incorporated into the plant tissues, and used as nutrients.
Rhizodegradation
Rhizodegradation, also called enhanced rhizosphere biodegradation,
phytostimulation, or plant-assisted bioremediation/degradation, is the
breakdown of contaminants in the soil through microbial activity that is
enhanced by the presence of the rhizosphere and is a much slower process than
phytodegradation. Microorganisms (yeast, fungi, or bacteria) consume and
digest organic substances for nutrition and energy. Certain microorganisms can
digest organic substances such as fuels or solvents that are hazardous to
humans and break them down into harmless products through biodegradation.
Natural substances released by the plant rootssugars, alcohols, and
acidscontain organic carbon that provides food for soil microorganisms, and
the additional nutrients enhance their activity. Biodegradation is also aided by
the way plants loosen the soil and transport water to the area.
Phytovolatilization
Phytovolatilization is the uptake and transpiration of a contaminant by a plant,
with release of the contaminant or a modified form of the contaminant to the
atmosphere from the plant. Phytovolatilization occurs as growing trees and
other plants take up water and the organic contaminants. Some of these
contaminants can pass through the plants to the leaves and volatilize into the
atmosphere at comparatively low concentrations.
Vlll
-------
PHYTOREMEDIATION RESOURCE MATRIX
The Phytoremediation Resource Matrix displays summary information on references listed in the Abstracts section of the Guide with the
exception of publications containing multiple papers. Both the Matrix and Abstracts sections are organized using the same contaminant-based
categories. Internet Resources are listed in a separate matrix following printed references. The first column of the Matrix displays the
document title, ordering number (when applicable), and page number of the full abstract in the Abstracts section. The second column
(Technology Type) lists the technologies that the article addresses. Definitions for these technologies can be found in the Technology Summary
on page vii. Column three denotes the media treated, and column four denotes the contaminants treated.
Document Title
Document Ordering Number
[Abstract Page Number in Guide]
Technology
Type
Media
'o
CO
1
Ground W
Contaminants
w
^0
*ฃH
cd
60
6
Pesticides/
Herbicides
w
13
tu
s
w
8
Radionucli
Explosives
GENERAL INFORMATION
The 1998 United States Market for Phytoremediation [1]
The Advancement of Phytoremediation as an Innovative
Environmental Technology for Stabilization, Remediation, or
Restoration of Contaminated Sites in Canada: A Discussion Paper
[2]
Bioremediation and Phytoremediation Glossary [2]
A Citizen's Guide to Phytoremediation [2]
EPA542-F-98-011
Compost-Enhanced Phytoremediation of Contaminated Soil [2]
EPA 530-R-98-008
Introduction to Phytoremediation [2]
Unspecified
Unspecified
Unspecified
Unspecified
Unspecified
Unspecified
IX
-------
Document Title
Document Ordering Number
[Abstract Page Number in Guide]
Legal and Social Concerns to the Development of Bioremediation
Technologies [3]
DE96015254
Phytoremediation [3]
EPA625-K-96-001
Phytoremediation [3]
Phytoremediation: A Clean Transition from Laboratory to
Marketplace? [3]
Phytoremediation: A New Technology Gets Ready to Bloom [3]
Phytoremediation Bibliography [4]
Phytoremediation Field Demonstrations in the U.S. EPA SITE
Program [4]
Phytoremediation: It Grows on You [4]
Phytoremediation on the Brink of Commercialization [4]
Phytoremediation: Technology Overview Report [5]
Phytoremediation: Using Green Plants to Clean Up Contaminated
Soil, Groundwater, and Wastewater [5]
Remediation Technologies Screening Matrix and Reference Guide
[5]
Technology
Type
Unspecified
Unspecified
Unspecified
Unspecified
Unspecified
Phytoextraction
Unspecified
Unspecified
Unspecified
Phytostabilization
Unspecified
Media
'o
CO
Ground Water
Contaminants
w
^0
C3
ฃ?
o
Pesticides/
Herbicides
w
3
1
Radionuclides
Explosives
-------
Document Title
Document Ordering Number
[Abstract Page Number in Guide]
Stemming the Toxic Tide [5]
Technology Evaluation Report: Phytoremediation [6]
Using Phytoremediation to Clean Up Contamination at Military
Installations [6]
DE97007971
Technology
Type
Phytoextraction
Unspecified
Unspecified
Media
'o
CO
Ground Water
Contaminants
w
^0
C3
ฃ?
o
Pesticides/
Herbicides
w
3
1
Radionuclides
Explosives
XI
-------
Document Title
Document Ordering Number
[Abstract Page Number in Guide]
Technology
Type
Media
_
0
CO
(3
>
^
1
O
Contaminants
0
a
60
O
^ U3
$3
11
3
1
w
3
o
0
3
w
>
ISl
"ft
X
w
ORGANIC CONTAMINANTS
Overviews
Mechanisms of Phytoremediation: Biochemical and Ecological
Interactions Between Plants and Bacteria [7]
Phytoremediation of TCE in Groundwater Using Populus [8]
Rhizodegradation
Phytodegradation
Phytovolatilization
Field Studies and Demonstrations
Demonstration Plan for Phytoremediation of Explosive-Contamina-
ted Groundwater in Constructed Wetlands at Milan Army
Ammunition Plant, Milan, Tennessee. Volumes 1 and 2. Final
Report [8]
ADAS 1112 1/8/XAB, ADAS 1 1 122/6/XAB
Evaluation of Various Organic Fertilizer Substrates and Hydraulic
Retention Times for Enhancing Anaerobic Degradation of
Explosives-Contaminated Groundwater While Using Constructed
Wetlands at the Milan Army Ammunition Plant, Milan, Tennessee
[8]
ADA349293
Field Scale Evaluation of Grass-Enhanced Bioremediation of PAH
Contaminated Soils [8]
Friendly Forests [9]
Phytodegradation
Phytodegradation
Rhizodegradation
Phytostabilization
Phytodegradation
Rhizodegradation
Xll
-------
Document Title
Document Ordering Number
[Abstract Page Number in Guide]
Groundwater Phytoremediation Test Facility, University of
Washington [9]
Phreatophyte Influence on Reductive Dechlorination in a Shallow
Aquifer Containing TCE [9]
Phytoremediation of Dissolved-Phase Trichloroethylene Using
Mature Vegetation [10]
Phytoremediation of Groundwater at Avesta Sheffield Pipe [10]
Phytoremediation of Organic and Nutrient Contaminants [10]
Pilot-Scale Use of Trees to Address VOC Contamination [10]
Screening of Aquatic and Wetland Plant Species for Phytoremedia-
tion of Explosives-Contaminated Groundwater from the Iowa Army
Ammunition Plant. Final Report [10]
ADA322455/7/XAB
Screening Submersed Plant Species for Phytoremediation of
Explosives-Contaminated Groundwater from the Milan Army
Ammunition Plant, Milan, Tennessee. Final Report [11]
Technology
Type
Rhizofiltration
Rhizodegradation
Phytovolatilization
Unspecified
Phytodegradation
Phytodegradation
Phytodegradation
Phytodegradation
Media
'o
CO
Ground Water
Contaminants
w
^0
C3
ฃ?
o
Pesticides/
Herbicides
W
3
1
Radionuclides
Explosives
Research
Adsorption of Naphthalene onto Plant Roots [11]
Aromatic Nitroreduction of Acifluorfen in Soils Rhizospheres and
Pure Cultures of Rhizobacteria [11]
Phytostabilization
Rhizodegradation
Xlll
-------
Document Title
Document Ordering Number
[Abstract Page Number in Guide]
Bacterial Inoculants of Forage Grasses that Enhance Degradation of
2-Chlorobenzoic Acid in Soil [11]
Bioremediation Bacteria to Protect Plants in Pentachlorophenol-
Contaminated Soil [12]
Decreased Transpiration in Popular Trees Exposed to 2,4,6-
Trinitrotoluene [12]
Degradation of Polychlorinated Biphenyls by Hairy Root Culture of
Solarium nigrum [12]
Detoxification of Phenol by the Aquatic Angiosperm, Lemna gibba
[12]
Effect of Hybrid Poplar Trees on Microbial Populations Important
to Hazardous Waste Bioremediation [13]
Effects of Ryegrass on Biodegradation of Hydrocarbons in Soil [13]
A Field Facility for Phytoremediation Research [13]
Greenhouse Evaluation of Agronomic and Crude Oil-
Phytoremediation Potential Among Alfalfa Genotypes [13]
The Influence of Planting and Soil Characteristics on
Mineralization of 2,4,5-T in Rhizosphere Soil [14]
Mineralization of 2,4-Dichlorophenol by Ectomycorrhizal Fungi in
Axenic Culture and in Symbiosis with Pine [14]
Technology
Type
Rhizodegradation
Rhizodegradation
Phytovolatilization
Phytodegradation
Phytodegradation
Rhizodegradation
Rhizodegradation
Phytodegradation
Phytodegradation
Rhizodegradation
Rhizodegradation
Media
'o
CO
Ground Water
Contaminants
w
^0
C3
ฃ?
o
Pesticides/
Herbicides
W
3
1
Radionuclides
Explosives
XIV
-------
Document Title
Document Ordering Number
[Abstract Page Number in Guide]
Phytoremediation Experimentation with the Herbicide Bentazon
[14]
Phytoremediation: Modeling Removal of TNT and Its Breakdown
Products [14]
Phytoremediation of 1,4-dioxane by Hybrid Poplars [14]
Phytoremediation of Hazardous Wastes [15]
Phytoremediation of Organic Contaminants: A Review of
Phytoremediation Research at the University of Washington [15]
Phytoremediation of Pesticide-Contaminated Soils [15]
Phytoremediation of Trichloroethylene with Hybrid Poplars [16]
Phytoremediation, Plant Uptake of Atrazine and Role of Root
Exudates [16]
Phytotreatment of TNT-Contaminated Groundwater [16]
Plant Cell Biodegradation of a Xenobiotic Nitrate Ester,
Nitroglycerin I [16]
Plant-Enhanced Remediation of Petroleum Contaminated Soil [17]
Plant-Enhanced Subsurface Bioremediation of Nonvolatile
Hydrocarbons [17]
Technology
Type
Phytodegradation
Phytodegradation
Phytovolatilization
Rhizodegradation
Phytodegradation
Phytodegradation
Rhizodegradation
Rhizofiltration
Rhizodegradation
Phytodegradation
Phytodegradation
Phytodegradation
Rhizodegradation
Rhizodegradation
Media
'o
C/3
Ground Water
Contaminants
w
o
C3
ฃ?
0
Pesticides/
Herbicides
w
"B
tu
S
Radionuclides
w
-------
Document Title
Document Ordering Number
[Abstract Page Number in Guide]
Potential of Phytoremediation as a Means for Habitat Restoration
and Cleanup of Petroleum Contaminated Wetlands [17]
Rhizosphere Microbial Populations in Contaminated Soils [17]
Transformation of TNT by Aquatic Plants and Plant Tissue
Cultures [18]
Uptake and Fate of Organohalogens from Contaminated
Groundwater in Wood Plants [18]
Technology
Type
Phytodegradation
Rhizodegradation
Phytodegradation
Phytodegradation
Phytovolatilization
Media
'o
CO
Ground Water
Contaminants
w
^0
C3
ฃ?
o
Pesticides/
Herbicides
w
3
1
Radionuclides
Explosives
XVI
-------
Document Title
Document Ordering Number
[Abstract Page Number in Guide]
Technology
Type
Media
'o
CO
Ground Water
Contaminants
w
^0
C3
ฃ?
o
Pesticides/
Herbicides
w
IS
1
Radionuclides
Explosives
INORGANIC CONTAMINANTS
Overviews
Emerging Technologies for the Remediation of Metals in Soils:
Phytoremediation [18]
Literature Review: Phytoaccumulation of Chromium, Uranium,
Plutonium in Plant Systems [19]
Remediation of Metal-Contaminated Sites Using Plants [19]
Restoration of Mined Lands Using Natural Processes [19]
Status of In Situ Phytoremediation Technology [19]
EPA 542-R-97-004
Unspecified
Phytoextraction
Phytoextraction
Unspecified
Phytoextraction
Phytostabilization
Rhizofiltration
Field Studies and Demonstrations
Phytoaccumulation of Trace Elements by Wetlands Plants: /.
Duckweed [20]
Relationship Between Sulfur Speciation in Soils and Plant
Availability [20]
Removal of Uranium from Water Using Terrestrial Plants [20]
Phytoextraction
Phytoextraction
Rhizofiltration
Research
Differences in Root Uptake of Radiocesium by 30 Plant Taxa [20]
Phytoextraction
1
XVll
-------
Document Title
Document Ordering Number
[Abstract Page Number in Guide]
Enhanced Accumulation of Pb in Indian Mustard by Soil-Applied
Chelating Agents [21]
Evaluation of Tamarisk and Eucalyptus Transpiration for the
Application of Phytoremediation [21]
Feasibility of Using Plants to Assist in the Remediation of Heavy
Metal Contamination at J-Field, Aberdeen Proving Ground,
Maryland. Final Report [21]
Lead-Contaminated Sediments Prove Susceptible to
Phytoremediation [21]
Lead Uptake and Effects on Seed Germination and Plant Growth in
a Pb Hyperaccumulator Brassica pekinensis Rupr. [22]
Metal Accumulation by Aquacultured Seedlings of Indian Mustard
[22]
Phytoextraction of Cadmium and Zinc from a Contaminated Soil
[22]
Phytoextraction of Zinc by Oat (Avena sativa), Barley (Hordeum
vulgare), and Indian Mustard (Brassica juncea) [23]
Phytoextraction: the Use of Plants to Remove Heavy Metals from
Soils [23]
Phytofiltration of Hazardous Cadmium, Chromium, Lead and Zinc
Ions by Biomass ofMedicago sativa (Alfalfa) [23]
Technology
Type
Phytoextraction
Phytoextraction
Phytoextraction
Phytoextraction
Phytoextraction
Phytoextraction
Phytoextraction
Phytoextraction
Phytoextraction
Rhizofiltration
Media
'o
CO
Ground Water
Contaminants
w
^0
C3
ฃ?
o
Pesticides/
Herbicides
w
3
1
Radionuclides
Explosives
XVlll
-------
Document Title
Document Ordering Number
[Abstract Page Number in Guide]
Phytoremediation of a Radiocesium-Contaminated Soil: Evaluation
of Cesium137 Bioaccumulation in the Shoots of Three Plant Species
[23]
Phytoremediation of Lead-Contaminated Soils: Role of Synthetic
Chelates in Lead Phytoextraction [24]
Phytoremediation of Selenium Laden Soils: A New Technology
[24]
Phytoremediation of Uranium-Contaminated Soils: Role of Organic
Acids in Triggering Uranium Hyperaccumulation in Plants [24]
Potential for Phytoextraction of 137Cs from a Contaminated Soil [25]
Potential Remediation of 137Cs and 90Sr Contaminated Soil by
Accumulation in Alamo Switchgrass [25]
Rhizofiltration: the Use of Plants to Remove Heavy Metals from
Aqueous Streams [25]
The Role of EDTA in Pb Transport and Accumulation by Indian
Mustard [25]
A Search for Lead Hyperaccumulating Plants in the Laboratory [26]
Selenium Accumulation by Brassica Napus Grown in Se-laden Soil
from Different Depths of Kersterson Reservoir [26]
Technology
Type
Phytoextraction
Phytoextraction
Phytoextraction
Phytoextraction
Phytoextraction
Phytoextraction
Rhizofiltration
Phytoextraction
Rhizofiltration
Phytoextraction
Phytoextraction
Media
'o
CO
Ground Water
Contaminants
w
^0
C3
ฃ?
o
Pesticides/
Herbicides
w
3
1
Radionuclides
Explosives
XIX
-------
Document Title
Document Ordering Number
[Abstract Page Number in Guide]
Test Plan for the Phytoremediation Studies of Lead-Contaminated
Soil from the Sunflower Army Ammunition Plant, Desoto, Kansas.
Vol. 1 and Vol. 2 [26]
ADA342667, ADA342668
Toxicity of Zinc and Copper to Brassica Species: Implications for
Phytoremediation [26]
Toxic Mercury Reduction and Remediation Using Transgenic
Plants with a Modified Bacterial Gene [27]
Zinc and Cadmium Accumulation in the Hyperaccumulator Thlaspi
Caerulescens in Response to Limestone and Compost Applications
to a Heavy Metal Contaminated Site in Palmerton, Pennsylvania
[27]
Technology
Type
Phytoextraction
Phytoextraction
Phytostabilization
Phytoextraction
Phytostabilization
Phytoextraction
Media
'o
CO
Ground Water
Contaminants
0
'8
I
O
Pesticides/
Herbicides
1
Radionuclides
Explosives
XX
-------
Web Site Title
URL
[Abstract Page Number in Guide]
Media
'o
CO
Ground Water
Contaminants
w
^0
C3
ฃ?
o
w
^0
C3
ฃ?
O
KH
INTERNET RESOURCES
Advanced Applied Technology Demonstration Facility (AATDF)
http://www.ruf.rice.edu/~aatdf [27]
Air Force Center for Environmental Excellence (AFCEE)
http://www.afcee.brooks.af.mil [27]
Alternative Treatment Technology Information Center (ATTIC)
http://www.epa.gov/attic [28]
CLU-IN: Hazardous Waste Clean-Up Information
http://clu-in.org [28]
Environmental Security Technology Certification Program (ESTCP)
http://www.estcp.org [28]
Federal Remediation Technologies Roundtable
http://www.frtr.gov [28]
GNET: The Global Network of Environment and Technology
http://www.gnet.org [28]
Great Plains/Rocky Mountain Hazardous Substance Research Center
http://www.ecc.ksu.edu/HSRC [28]
Ground Water Remediation Technologies Analysis Center (GWRTAC)
http://www.gwrtac.org [29]
XXI
-------
Web Site Title
URL
[Abstract Page Number in Guide]
Innovative Treatment Remediation Demonstration (ITRD)
http://www.em.doe.gov/itrd [29]
Interstate Technology and Regulatory Cooperation Working Group (ITRC)
http://www.sso.org/ecos/itrc [29]
PHYTONET - Phytoremediation Electronic Newsgroup Network
http://www.dsa.unipr.it/phytonet [29]
Remediation Technologies Development Forum (RTDF)
Phytoremediation of Organics Action Team
http://www.rtdf.org/public/phyto [29]
Strategic Environmental Research and Development Program (SERDP)
http://www.serdp.gov [30]
U.S. Army Corps of Engineers Phytoremediation Research
http://www.wes.army.mil/EL/phyto [30]
U.S. Army Environmental Center (USAEC)
http ://aec-www. apgea. army. mil : 8080 [30]
U.S. Department of Agriculture (USD A)
http://www.usda.gov [29]
Media
'o
CO
Ground Water
Contaminants
w
^0
*ฃH
cd
60
6
w
0
'8
CS
60
^H
O
KH
XX11
-------
ABSTRACTS OF PHYTOREMEDIATION RESOURCES
The resources below describe the contents of pertinent phytoremediation documents and Internet resources. The
references and resources are organized alphabetically within each of the following categories:
General Information 1
Publications Containing Multiple Papers 6
Organic Contaminants 7
Overviews 7
Field Studies and Demonstrations 8
Research 11
Publications Containing Multiple Papers 18
Inorganic Contaminants 18
Overviews 18
Field Studies and Demonstrations 20
Research 20
Publications Containing Multiple Papers 27
Internet Resources 27
To quickly identify documents and resources pertinent to your interest area, see the Phytoremediation Resource
Matrix on pages ix-xxii of this Guide. The documents and resources in the matrix are organized alphabetically
within the categories identified above. Listings in the matrix can be cross-referenced with the abstracts by referring
to the page number provided in the matrix. In an effort to limit the number of resources listed here, documents
published prior to 1990 are not included. These abstracts were obtained from several databases, including the
National Technical Information Service, Energy Science and Technology, Enviroline, Water Resources Abstracts,
and Pollution Abstracts as well as several Internet resources.
General Information
The 1998 United States Market for
Phytoremediation
Glass, D.J.
D. Glass Associates, Inc., Needham, MA 140 pp April
1998
Phytoremediation, the use of plants, trees, and other
vegetation to remove, sequester, or degrade
environmental contaminants, has attracted a great deal
of interest in recent years. Drawing on the abilities of
plants to accumulate metals and other substances or
take up and transpire large amounts of water,
phytoremediation is an effective, low-cost treatment
technology that is beginning to gain the attention of
private and industrial site owners, regulators, and the
environmental engineering community. This report
includes a technology summary, commercial company
profiles, research group profiles, an industry analysis
and market forecast, summaries of several completed
and ongoing phytoremediation projects, a review of the
advantages and disadvantages of the technology, and a
glossary.
-------
The Advancement of Phytoremediation as an
Innovative Environmental Technology for
Stabilization, Remediation, or Restoration of
Contaminated Sites in Canada: A Discussion Paper
Mclntyre, T. and Lewis, G.M.
Journal of Soil Contamination v 6:3 p 227(15) May
1997
Environment Canada's Environmental Technologies
Advancement Division is exploring the potential of
phytoremediation as a major, long-term technology
approach. The benefits and limitations of
phytoremediation and its potential for bioremediation
of soil and ground water in Canada are discussed.
Research issues that will need to be addressed to further
phytoremediation technology are examined. Other
regulatory, legal, commercial, and social issues are
considered briefly.
Bioremediation and Phytoremediation Glossary
Bentjen, S.
Available at
http://members.tripod.com/~bioremediation
This glossary lists terms related to bioremediation
(microbial degradation) and phytoremediation
(remediation using green plants) of environmental
pollutants. Links to other environmental glossaries
appear at the bottom of the page.
A Citizen's Guide to Phytoremediation
U.S. EPA, Office of Solid Waste and Emergency
Response
6 pp August 1998
Available at http://clu-in.org
| EPA Document Number: EPA 542-F-98-011
EPA's Technology Innovation Office has published a
Technology Fact Sheet that describes what
phytoremediation is, how it works, what its limitations
are, and where to find additional information.
Compost-Enhanced Phytoremediation of
Contaminated Soil
U.S. EPA, Office of Solid Waste and Emergency
Response
Published w. Analysis of Composting as an
Environmental Remediation Technology p 87(12)
April 1998
|EPA Document Number: EPA 530-R-98-008 |
Phytoremediation is a developing technology in which
higher plants and microorganisms associated with plant
roots are the active agents for uptake and/or
degradation of toxic inorganic and organic compounds
in soil and water. Plants can also provide containment
by reducing the erosional transport of contaminated
soil. Numerous reports indicate that plants can take up
and degrade toxic organic compounds in soil, while
other work indicates microorganisms in the rhizosphere
are very competent degraders of soil-borne organics.
This process might be suitable for soil remediation
and/or inexpensive confinement of shallow
contaminated water. Phytoremediation of
metal-contaminated soil relies on the ability of plants to
accumulate metals at concentrations substantially above
those found in the soil in which they grow.
Phytoremediation has very large economic advantages
over mechanically intensive technologies.
Introduction to Phytoremediation
U.S. EPA, National Risk Management Research
Laboratory
To be issued in 1999
To be available at http://www.rtdf.org
This handbook is the work of the EPA
Phytoremediation Handbook Team in conjunction with
the Remediation Technologies Development Forum
(RTDF) Phytoremediation Action Team. It was
developed to provide a tool for site regulators, owners,
neighbors, and managers to evaluate the applicability of
phytoremediation to a site. Phytoremediation projects
have been proposed or applied to ecosystem restoration
and soil, surface water, ground water, and sediment
remediation. This document identifies, defines, and
provides a framework to evaluate these
phytoremediation applications, although it is not a
design guide. It also presents case studies illustrating
field applications of phytoremediation.
-------
Abstracts of Phytoremediation Resources
General Information
Legal and Social Concerns to the Development of
Bioremediation Technologies
Bilyard, G.R.;etal.
150 pp Sep 1996
Document Number: DE960 15254
The social and legal framework within which
bioremediation technologies must be researched,
developed, and deployed in the U.S. are discussed in
this report. Discussions focus on policies, laws and
regulations, intellectual property, technology transfer,
and stakeholder concerns. These discussions are
intended to help program managers, scientists and
engineers understand the social and legal framework
within which they work, and be cognizant of relevant
issues that must be navigated during bioremediation
technology research, development, and deployment
activities. While this report focuses on the legal and
social environment within which the DOE operates, the
laws, regulations and social processes could apply to
other sites nationwide. This report identifies specific
issues related to bioremediation technologies, including
those involving the use of plants; native, naturally
occurring microbes; non-native, naturally occurring
microbes; genetically engineered organisms; and
microbial products (e.g., enzymes, surfactants,
chelating compounds).
Phytoremediation
Rock, S. and Pope, D.
Published in Seminars: Bioremediation of Hazardous
Waste Sites: Practical Approaches to Implementation p
8.1(9) 1996
|EPA Document Number: EPA625-K-96-001 |
Chapter eight of the seminar publication contains a
description of the different aspects of phytoremediation,
applications and examples, a bibliography, and
illustrations from the poster session.
Phytoremediation
Salt, D.E.; Smith, R.D.; and Raskin, I.
Annual Review of Plant Physiology and Plant
Molecular Biology v 49 p 643(26) 1998
Phytoremediation, a cost-effective plant-based approach
to remediation, takes advantage of the ability of plants
to concentrate elements and compounds from the
environment and to metabolize various molecules in
their tissues. Several field trials have confirmed the
feasibility of using plants for environmental cleanup.
This review concentrates on the most developed subsets
of phytoremediation technology and on the biological
mechanisms that make phytoremediation work.
Phytoremediation: A Clean Transition from
Laboratory to Marketplace?
Boyajian, G.E. and Carreira, L.H.
Natural Biotechnology v 15:2 p 127(2) 1997
In recent years, the potential of plants for
environmental cleanupphytoremediationhas been
recognized, and U.S. government agencies and private
corporations have responded by increasingly supporting
research in this area. The report in this issue by Goel et
al. both advances our basic knowledge of plant
biochemistry and demonstrates that plants are indeed
capable of tackling such exotic xenobiotic contaminants
as nitroglycerin.
Phytoremediation: A New Technology Gets Ready to
Bloom
Bishop, J.
Environmental Solutions v 10:4 p 29(6) May-June 1997
Phytoremediation is the use of selected crop plants or
trees to extract or promote degradation of toxic
substances in soils, ground water, surface water,
wastewater and sediments. It may be possible in some
cases to harvest such contaminants as heavy metals that
have been taken up by plants and recover them for
recycling. In other variations, plants stimulate the
growth of naturally occurring microbial populations,
which then degrade organic contaminants, such as
petroleum hydrocarbons, in soils. At appropriate sites,
the cost of applying phytoremediation techniques may
range from half to less than 20% of the cost of using
physical, chemical, or thermal techniques.
-------
Abstracts of Phytoremediation Resources
General Information
Phytoremediation Bibliography
Available at http://www.rtdf.org
This searchable bibliography of over 1,400 citations is
the work of the EPA Phytoremediation Handbook Team
in conjunction with the Remediation Technologies
Development Forum (RTDF) Phytoremediation Action
Team. The bibliography is updated frequently.
Phytoremediation Field Demonstrations in the U.S.
EPA SITE Program
Rock, S. and Beckman, S.
In Situ and On-Site Bioremediation: Volume 3
Battelle Press, Columbus, OH p 323 [abstract only]
1998
U.S. EPA National Risk Management Research
Laboratory's SITE program is evaluating
Phytoremediation's efficacy and cost at field scale
demonstrations on sites in Oregon, Utah, Texas, and
Ohio. The Superfund Innovative Technology
Evaluation (SITE) Program is a part of EPA's research
into alternative cleanup methods for hazardous waste
sites. The EPA teamed with USAF, USGS, Ohio EPA,
Chevron USA, Phytotech, Inc., and Phytokinetics, Inc.
to accomplish these demonstrations. At a wood treater
in Portland, Oregon, shallow soil contaminated with
PCP and PAHs is being treated with a perennial
ryegrass. In Ogden, Utah, a combination of poplar
trees, juniper trees, alfalfa, and fescue has been planted
to remediate a petroleum spill which has polluted both
the soil and the ground water. On an Air Force facility
near Fort Worth, Texas, cottonwood trees are being
used to intercept a part of a large TCE ground water
plume. In Ohio, the shallow soil of a former metal
plating facility is the site for a demonstration of
phytoextraction of lead, cadmium, and hexavalent
chromium using Indian mustard. Each demonstration
includes monitoring the soil, ground water, and plant
material. The sites were planted in 1996, and will be
monitored until at least 1999. [Abstract only.
Additional information is available at http://clu-in.org
under the SITE Demonstration Program page.]
Phytoremediation: It Grows on You
Boyajian, G. E. and Devedjian, D.L.
Soil & Groundwater Cleanup p 22(5) February-March
1997
Phytoremediation is a small but growing subset of in
situ remediation technologies for contaminated soil.
Plants can be effective remediators by reaching
contaminants through their root systems, their ability to
accumulate metals and degrade organic compounds,
and their reduced cost compared with other approaches.
However, only those plants having the appropriate
biochemical pathways are effective for soil cleanup.
Identification of appropriate plants for remediation of
organic compounds and heavy metals is discussed.
Phytoremediation on the Brink of
Commercialization
Watanabe, M.E.
Environmental Science & Technology v 31:4 p 182A(4)
1997
Academic, government, and corporate researchers have
a body of data on the ability of certain plants to either
remove pollutants from the environment or render them
harmless, and they are looking for ways to improve
these traits through plant breeding and molecular
techniques. In the past three years, at least three new
companies have formed to use plants to clean sites
contaminated with heavy metals or organics.
Phytoremediation is a natural process carried out by
plants, especially those that are able to survive in
contaminated soil and water. Hyperaccumulators are
plants that can absorb high levels of contaminants with
their roots and concentrate them either there or in
shoots and leaves. Researchers have found
hyperaccumulator species by collecting plants in areas
where soil contains greater than usual amounts of
metals or other potentially toxic compounds because of
geological factors or pollution. Among the plants that
have been collected and used in field trials are species
from the genus Thlaspi, or Alpine pennycress, which
accumulate zinc, cadmium, or lead, w&Alyssum
species, which accumulate nickel. Both genera belong
to the mustard family Brassicaceae. Plants from other
families also have been shown to remove cobalt,
copper, chromium, manganese, or selenium from
contaminated soils.
-------
Abstracts of Phytoremediation Resources
General Information
Phytoremediation: Technology Overview Report
Miller, R.
Groundwater Remediation Technologies Analysis
Center, Pittsburgh, PA 26 pp 1996
Available at http://www.gwrtac.org
Phytoremediation uses plants to cleanup contaminated
soil and ground water, taking advantage of plants'
natural abilities to take up, accumulate, and/or degrade
constituents of their soil and water environments.
Research results report it to be applicable to a broad
range of contaminants including numerous metals,
radionuclides, and various organic compounds (such as
chlorinated solvents, BTEX, PCBs, PAHs,
pesticides/insecticides, explosives, nutrients, and
surfactants). According to information reviewed,
general site conditions best suited for use of
Phytoremediation include large areas of low to
moderate surface soil (0 to 3 feet) contamination or
large volumes of water with low-level contamination
subject to low (stringent) treatment standards. Major
advantages reported for phytoremediation as compared
to traditional remediation technologies include the
possibility of generating less secondary wastes, minimal
associated environmental disturbance, and the ability to
leave soils in place and in a usable condition following
treatment. Cited disadvantages include the long lengths
of time required (usually several growing seasons),
depth limitations (3 feet for soil and 10 feet for ground
water), and the possibility of contaminant entrance into
the food chain through animal consumption of plant
material.
Phytoremediation: Using Green Plants to Clean Up
Contaminated Soil, Groundwater, and Wastewater
Negri, M. C. and Hinchman, R.R.
9 pp 1996
Phytoremediation, an emerging cleanup technology for
contaminated soils, ground water, and wastewater that
is both low-tech and low-cost, is defined as the
engineered use of green plants to remove, contain, or
render harmless such environmental contaminants as
heavy metals, trace elements, organic compounds, and
radioactive compounds in soil or water. Current
research at Argonne National Laboratory includes a
successful field demonstration of a plant bioreactor for
processing the salty wastewater from petroleum wells
and a greenhouse experiment on zinc uptake in hybrid
poplar (Populus sp.). Because the roots sequester most
of the contaminant taken up in most plants, a major
objective of this program is to determine the feasibility
of root harvesting as a method to maximize the removal
of contaminants from soils. Available techniques and
equipment for harvesting plant roots, including young
tree roots, are being evaluated and modified as
necessary for use.
Remediation Technologies Screening Matrix and
Reference Guide
Federal Remediation Technologies Roundtable
Available at http://www.frtr.gov
This reference guide provides a "yellow pages" of
remediation technologies. It is intended to be used to
screen and evaluate candidate cleanup technologies for
contaminated installations and waste sites in order to
assist remedial project managers (RPMs) in selecting a
remedial alternative. It incorporates cost and
performance data to the maximum extent available and
focuses primarily on demonstrated technologies. All
levels of remediation technologies are included in this
guide. These technologies are applicable at all types of
site cleanups: Superfund, DoD, DOE, RCRA, state,
private, etc.
Stemming the Toxic Tide
Dutton, G.
Compressed Air v 101:4 p 38(5) June 1996
Phytoremediation, the use of plants to clean up toxic
substances in soil and water, has been proposed as an
effective treatment for contaminated soil and sludge at
industrial locations, including Superfund sites. The
approach represents a cost-effective alternative to
conventional remediation methods. Elements being
considered as targets of phytoextraction include nickel,
zinc, copper, selenium, cadmium, chromium, lead,
cobalt, manganese, and several radionuclides. Specific
plants and processes being used to clean soil and water
are identified. Problems with the approach include
disposal issues and time and depth limitations.
-------
Abstracts of Phytoremediation Resources
General Information
Technology Evaluation Report: Phytoremediation
Schnoor, J.L.
Ground-Water Remediation Technologies Analysis
Center
43 pp October 1997
Available at http://www.gwrtac.org
Phytoremediation is best applied at sites with shallow
contamination by organic, nutrient, or metal pollutants.
Phytoremediation is well-suited for use at very large
field sites where other methods of remediation are not
cost-effective or practicable; at sites with low
concentrations of contaminants where only "polishing
treatment" is required over long periods of time; and in
conjunction with other technologies where vegetation is
used as a final cap and closure of the site. There are
limitations to the technology that need to be considered
carefully before it is selected for site remediation. These
include: limited regulatory acceptance, long duration of
time sometimes required for clean-up to below action
levels, potential contamination of the vegetation and
food chain, and difficulty establishing and maintaining
vegetation at some toxic waste sites. This detailed
report discusses the current status of phytoremediation
to treat soils and ground water. Several field
demonstration summaries are presented, with such
information as: participants, compounds treated, site
characteristics, results, and contacts.
Using Phytoremediation to Clean Up Contamination
at Military Installations
Zellmer, S.D.; Hinchman, R.R.; Negri, M.C.;
Schneider, J.F.; and Gatliff, E.G.
19 pp July 1997
|NTIS Document Number: DE97007971
An emerging technology for cleaning contaminated
soils and shallow ground water is phytoremediation, an
environmentally friendly, low-cost, and low-tech
process. Phytoremediation encompasses all
plant-influenced biological, chemical, and physical
processes that aid in the uptake, degradation, and
metabolism of contaminants by either plants or
free-living organisms in the plant's rhizosphere. A
phytoremediation system can be viewed as a biological,
solar-driven, pump-and-treat system with an extensive,
self-extending uptake network (the root system) that
enhances the soil and below-ground ecosystem for
subsequent productive use. Argonne National
Laboratory has been conducting basic and applied
research in phytoremediation since 1990.
Publications Containing Multiple Papers
Phytoremediation of Soil and Water Contaminants
Kruger, E.L.; Anderson, T.A.; and Coats, J.R. (eds.)
Developed from a symposium sponsored by the
Division ofAgrochemicals and the Division of
Environmental Chemistry at the 212th National
Meeting of the American Chemical Society, August
25-29, 1996, Orlando, Florida.
American Chemical Society, Washington, DC 318 pp
1997
Emerging Technologies in Hazardous Waste
Management VII: The 7th ACS Special Symposium,
17-20 September 1995, Atlanta, Georgia
Tedder, D.W. (ed.)
American Chemical Society, Washington, DC 1352 pp
1995
Bioremediation Through Rhizosphere Technology
Anderson, T.A. and Coats, J.R. (eds.)
American Chemical Society, Washington, DC 249 pp
1994
Bioremediation of Surface and Subsurface
Contamination (Annals of the New York Academy
of Sciences, Vol. 829)
Bajpai, R. and Zappi, M. (eds.)
1997
In Situ and On-Site Bioremediation, Vol. 3
Alleman, B.C. andLeeson, A. (eds.)
Battelle Press, Columbus, OH 570 pp 1997
-------
Abstracts of Phytoremediation Resources
Organic Contaminants
Proceedings of the Annual Conference on Hazardous
Waste Research
Great Plains/Rocky Mountain Hazardous Substance
Research Center, Kansas State University, Manhattan,
KS
Tables of contents, abstracts, and selected papers from
the 1994 Ninth Annual Conference onward are
available at http://www.engg.ksu.edu/HSRC
Proceedings of the International Seminar on Use of
Plants for Environmental Remediation (ISUPER)
Council for Promotion of Utilization of Organic
Materials (CPOUM), Kosaikan, Tokyo, Japan 1997
Annual International Conference on
Phytoremediation
International Business Communications,
Southborough, MA (1st: 1996, 2nd: 1997, 3rd: 1998)
Proceedings of the 12th Annual Conference on
Contaminated Soils: Analysis, Site Assessment, Fate,
Environmental and Human Risk Assessment,
Remediation and Regulation, 20-23 October 1997,
Amherst, MA
Kostecki, P. T. and Calabrese, E.J. (eds.)
Environmental Health Sciences Program, School of
Public Health, University of Massachusetts, Amherst,
MA, 1997
Journal of Soil Contamination
v 7:4 July 1998
Soil & Groundwater Cleanup
February-March 1999
Soil & Groundwater Cleanup
February-March 1998
International Journal of Phytoremediation
First Issue (v 1:1) to be published by CRC Press in
March 1999.
Phytoremediation
Terry, N. andBanuelos, G.S. (eds.)
Ann Arbor Press, (In press. Release expected Summer
1999).
Superfund Innovative Technology Evaluation
Program: Technology Profiles, 9th Edition
I EPA Document Number: EPA 540-R-97-502
Organic Contaminants
Overviews
Mechanisms of Phytoremediation: Biochemical and
Ecological Interactions Between Plants and Bacteria
Siciliano, S.D. and Germida, J.J.
Environmental Reviews v 6:1 p 65(15) 1998
This review concentrates on plant-bacteria interactions
that increase the degradation of hazardous organic
compounds in soil. Plants and bacteria can form
specific associations in which the plant provides the
bacteria with a specific carbon source that induces the
bacteria to reduce the toxicity of the contaminated soil.
Alternatively, plants and bacteria can form nonspecific
associations in which normal plant processes stimulate
the microbial community, which in the course of
normal metabolic activity degrades contaminants in
soil. Plants can provide carbon substrates and nutrients,
as well as increase contaminant solubility. These
biochemical mechanisms increase the degradative
activity of bacteria associated with plant roots. In
return, bacteria can augment the degradative capacity
of plants or reduce the toxicity of the contaminated soil.
-------
Abstracts of Phytoremediation Resources
Organic Contaminants
Phytoremediation of TCE in Groundwater using
Populus
Chappell, J.
Status Report Prepared for the U.S. EPA Technology
Innovation Office, 1997
Available at http://clu-in.org
This report is intended to provide a basic orientation to
Phytoremediation and a review of its use for shallow
ground water remediation. It contains information
gathered from a range of currently available sources,
including project documents, reports, periodicals,
Internet searches, and personal communication with
involved parties. No attempts were made to
independently confirm the resources used.
Field Studies and Demonstrations
Demonstration Plan for Phytoremediation of
Explosive-contaminated Groundwater in
Constructed Wetlands at Milan Army Ammunition
Plant, Milan, Tennessee. Volumes 1 and 2. Final
Report
Behrends, L.; Sikora, F.; Kelly, D.; Coonrod, S.; and
Rogers, B.
209 pp (Vol. 1), 496 pp (Vol. 2) Jan 1996
NTIS Document Number: ADA311121/8/XAB (Vol. 1)
ADA311122/6/XAB (Vol. 2)
This plan demonstrates the technical and economic
feasibility of using phytoremediation in an artificial,
constructed wetlands for treatment of
explosives-contaminated ground water at Milan Army
Ammunition Plant. Validated data on cost and
effectiveness of this demonstration will be used to
transfer this technology to the user community.
Evaluation of Various Organic Fertilizer Substrates
and Hydraulic Retention Times for Enhancing
Anaerobic Degradation of Explosives-Contaminated
Groundwater While Using Constructed Wetlands at
the Milan Army Ammunition Plant, Milan,
Tennessee
Behrends, L.L.; Almond, R.A.; Kelly, D.A.; Phillips,
W.D.; and Rogers, W.J.
383 pp May 1998
|NTIS Document Number: ADA349293 |
This document describes studies conducted at the Milan
Army Ammunition Plant (MAAP) to improve the
design, operation, and cost of gravel-based anaerobic
cells when phytoremediating explosives-contaminated
ground water. A typical gravel-based wetland consists
of an anaerobic cell for removing the bulk of the
explosive-contaminates, and an aerobic cell for
removing CBOD-5, nutrients, total suspended solids,
and small quantities of explosive by- products. The
cells are connected in series with the anaerobic cell
being the first cell. Small-scale anaerobic test cells were
used to determine: (1) If the hydraulic retention time of
a large demonstration-scale anaerobic cell at MAAP
could be reduced, and (2) if other carbon sources could
be used as an anaerobic feedstock. The study results
indicate that: (1) The existing anaerobic cell's 7.5-day
retention time should not be reduced since residual
explosive by-products were present in the effluent of
treatments with a 3.5-day retention time. (2) Daily
application of a relatively soluble substrate, such as
molasses syrup, will provide better explosives removal
than periodic application of less soluble substrates such
as milk replacement starter and sewage sludge.
Field Scale Evaluation of Grass-Enhanced
Bioremediation of PAH Contaminated Soils
Sorensen, D.L.; Sims, R.C.; and Qiu, X.
EPA Risk Reduction Engineering Laboratory's 20th
Annual Research Symposium, 15-17 March 1994,
Cincinnati, OH p 92(3)
A field pilot-scale study was launched to assess the
potential of prairie grasses to enhance bioremediation
of PAH-contaminated soils. The ongoing research is
designed to test the hypothesis that the deep, fibrous
root system of the grasses improves aeration in soil and
degradative capability in the rhizosphere. Average
phenanthrene levels declined dramatically in both
vegetated and unvegetated plots. Acenaphthylene also
declined in both sites with time and was detected in
higher concentrations in unvegetated shallow soil
relative to vegetated shallow soil. Preliminary data
indicate slow degradation in test plots and provide
some evidence that Buffalo grass sod planting
enhanced degradation in the near surface.
-------
Abstracts of Phytoremediation Resources
Organic Contaminants
Friendly Forests
Miller, J. A.
Third International Conference on Health, Safety,
Environment in Oil and Gas Exploration and
Production, 9 June-12 Sep 1996, New Orleans,
Louisiana
Society of Petroleum Engineers (SPE), Inc.,
Richardson, TX p 717(6) 1996
Trees can be used to extract ground water from aquifers
and serve as a natural pumping system for
contaminated ground water plume control.
Simultaneously, the trees create a rhizosphere
biodegradation zone and extract hydrocarbons through
uptake in the transpiration stream. Phytoremediation
has been proposed for
cleanup of historical petroleum hydrocarbon and
chlorinated hydrocarbon contamination as an in situ
treatment method of reasonable cost that requires little
maintenance. The initiative of one major oilfield
service company at a Louisiana site is described. The
demonstration began in June 1995 with the planting of
92 hybrid poplar trees for the purposes of (1)
controlling ground water movement; (2) taking up
constituents from soil and ground water; and (3)
enhancing bioremediation of soil and ground water in
the rhizosphere. Results to date are reported.
Groundwater Phytoremediation Test Facility,
University of Washington
Contact: Stuart E. Strand, Research Associate Professor
Box 352100, College of Forest Resources, University of
Washington, Seattle, WA 98195
Tel/Fax: 206-543-5350 E-mail:
sstrand@u. washington.edu
The Ground water Phytoremediation Test Facility
(GWPTF) was constructed in 1994 in Fife,
Washington. The facility covers about one-quarter acre
and is equipped with 12 double-lined test beds, each 12
ft x 18 ft x 4.5 ft deep. The site has equipment for
handling, mixing, and delivering synthetically
contaminated water and for decontaminating the
effluent water using carbon adsorption units. The test
facility has been used to provide the first near-full-scale
testing of phytoremediation of chlorinated
hydrocarbons in ground water. Results indicate nearly
complete uptake of TCE and carbon tetrachloride by
poplar trees with no detectable TCE or CT emissions.
The GWPTF test beds allow easy monitoring of
influent and effluent mass fluxes of chlorinated
solvents. A permit is required to conduct
demonstrations. Technology developers and the site
manager work together to file the permit. It takes about
six months to obtain a permit. State and local
regulations apply. Permission to add injectants for
remediation may be granted on a case-by-case basis.
Phreatophyte Influence on Reductive Dechlorination
in a Shallow Aquifer Containing TCE
Lee, R.W.; Jones, S.A.; Kuniansky, E.L.; Harvey, G.J.;
and Eberts, S.M.
Bioremediation and Phytoremediation: Chlorinated
and Recalcitrant Compounds
Battelle Press, Columbus, OH p 263(6) 1998
At Carswell Field, Fort Worth Naval Air Station Joint
Reserve Base in Texas, a phytoremediation
demonstration project is being conducted to determine
if eastern cottonwood trees are effective in remediating
shallow trichloroethylene-contaminated ground water.
Two tree plots were prepared and planted in April
1996, and baseline sampling began shortly thereafter.
A stand of whips (cuttings) and a stand of 1- to
2-year-old trees are included in the study. After 18
months, the root systems were not sufficiently
established to alter the chemistry and microbiology of
the ground water. However, a nearby mature
cottonwood tree was found to have changed ground
water chemistry, causing oxygen consumption, iron
reduction, methane production, and reductive
dechlorination of TCE in the vicinity of the root
system. Ground water levels and TCE concentrations in
the aquifer will be monitored to establish baseline
conditions and to map changes within the aquifer
throughout the life of the demonstration. Costs
associated with the planting and cultivation of each tree
stand will be compared to help assess the practicability
of phytoremediation as a cleanup technology.
Demonstration sampling will continue until the year
2000.
-------
Abstracts of Phytoremediation Resources
Organic Contaminants
Phytoremediation of Dissolved-Phase
Trichloroethylene Using Mature Vegetation
Doucette, W.J.; Bugbee, B.; Hayhurst, S.; Plaehn,
W.A.; Downey, D.C.; Taffinder, S.A.; and Edwards, R.
Bioremediation and Phytoremediation: Chlorinated
and Recalcitrant Compounds
Battelle Press, Columbus, OH p 251(6) 1998
At a study site at Cape Canaveral Air Station, FL,
transpiration gas and tissues of live oak, castor bean,
and saw palmetto growing above a trichloroethylene
(TCE)-contaminated ground water plume were
collected and analyzed for TCE and its metabolites.
Results showed that measurable levels of TCE were
detected in seven of 15 transpiration-gas samples.
Trichloroethylene, 2,2,2-trichloroethanol,
2,2,2-trichloroacetic acid, and 2,2-dichloroacetic acid
were detected in all plant tissue types from all three
species. Generally, metabolite concentrations were
higher than TCE concentrations. Highest TCE
concentrations were found in the roots, while highest
metabolite concentrations were detected in leaf and
stem samples.
Phytoremediation of Groundwater at Avesta
Sheffield Pipe
Glanders, G.A. and Lundquist, J.B.
Iron and Steel Engineer v 75:5 p 39(3) May 1998
Ground water contaminated with volatile organic
compounds and nitrate from spent pickle liquor is
being remediated by a phytoremediation process using
limpograss. Limpograss is a high protein,
nitrate-loving grass that also serves as a valuable source
of animal feed.
Phytoremediation of Organic and Nutrient
Contaminants
Schnoor, J.L.; Licht, L.A.; McCutcheon, S.C.; Wolfe,
N.L.; and Carreira, L.H.
Environmental Science & Technology v 29:7 p 318A(6)
1995
Phytoremediation, the use of vegetation for the in situ
treatment of contaminated soils and sediments, is an
emerging technology that promises effective and
inexpensive cleanup of certain hazardous waste sites.
Remediation using plants is best suited to sites with
shallow contamination (<15 ft depth); moderately
hydrophobic pollutants (BTEX compounds, chlorinated
solvents, nitrotoluene ammunition wastes), or excess
nutrients (nitrate, ammonium, and phosphate). The
technology has been used effectively in a number of
full-scale and pilot studies that are mentioned in the
article.
Pilot-Scale Use of Trees to Address VOC
Contamination
Compton, H.R.; Haroski, D.M.; Hirsh, S.R.; and
Wrobel, J.G.
Bioremediation and Phytoremediation: Chlorinated
and Recalcitrant Compounds
Battelle Press, Columbus, OH p 245(6) 1998
At the Aberdeen Proving Ground, MD, significant
levels of VOCs have been detected in the ground water,
primarily in the surficial aquifer, at depths to
approximately 12 m. A study was conducted to assess
phytoremediation as a viable alternative for
remediating the shallow ground water contamination.
Over a 4000-m2 plot, 183 hybrid poplar trees were
planted, and seasonal transpiration gas and water
samples were analyzed. The data revealed that the trees
were removing or degrading VOCs at the site as
indicated by the presence of VOCs and their
degradation products in transpiration gas, condensate,
and leaf tissue. A gradient of ground water flow has
formed toward the phytoremediation test plot, with a
ground water depression of approximately 0.1 m.
Analysis of nematode samples suggested that the soil
habitat is improving due to the presence of the trees.
Screening of Aquatic and Wetland Plant Species for
Phytoremediation of Explosives-Contaminated
Groundwater from the Iowa Army Ammunition
Plant. Final Report
Best, E.P.; Zappi, M.E.; Fredrickson, H.L.; Sprecher,
S.L.; and Larson, S.L.
74 pp January 1997
Document Number: ADA322455/7/XAB
10
-------
Abstracts of Phytoremediation Resources
Organic Contaminants
Munitions material such as 2,4,6-trinitrotoluene (TNT)
and hexahydro-1,3,5- trinitro-l,3,5-triazine (RDX) and
their combustion and decomposition products can enter
the environment from production activities, field usage,
and disposal. The capabilities of plants to absorb,
accumulate, and metabolize, directly or indirectly,
various organic substances suggest their use in the
phytoremediation of contaminated environments.
Screening Submersed Plant Species for
Phytoremediation of Explosives-Contaminated
Groundwater from the Milan Army Ammunition
Plant, Milan, Tennessee. Final Report
Best, E.P.; Sprecher, S.L.; Fredrickson, H.L.; Zappi,
M.E.; and Larson, S.L.
89 pp November 1997
Phytoremediation systems are being considered as an
alternative to other ground water extraction and surface
treatment techniques due to their ability to enhance
removal of potentially toxic or mutagenic munitions
material such as 2,4,6-trinitrotoluene (TNT),
hexahydro-1,3,5- trinitro-l,3,5-triazine (RDX), and
their degradation products. This study evaluated the
relative ability often species to decrease levels of TNT
and RDX explosives and related contaminants in
ground water at the Milan Army Ammunition Plant,
Milan, Tennessee.
Research
Adsorption of Naphthalene onto Plant Roots
Schwab, A. P.; Al-Assi, A. A.; and Banks, M. K.
Journal of Environmental Quality v 27:1 p 220(5)
January-February 1998
During phytoremediation, PAHs that are resistant to
degradation may adsorb to the surfaces of plant roots,
making the roots an important sink for specific PAHs.
Tall fescue and alfalfa were grown in a greenhouse
under controlled conditions, and roots were harvested
at three growth stages: vegetative, flowering, and
mature. Naphthalene adsorption to the various plant
roots was then evaluated. Results show that the mass of
naphthalene volatilized was the largest component of
the mass balance (32-45%). The mass in solution was
usually greater than that adsorbed to the roots. The
affinity of naphthalene for alfalfa roots was greater than
that for tall fescue roots, but fescue roots were present
in much greater quantities in the soil compared with
alfalfa. Naphthalene adsorption on the roots of both
plant species increased with plant age.
Aromatic Nitroreduction of Acifluorfen in Soils
Rhizospheres and Pure Cultures of Rhizobacteria
Zablotowicz, R.M.; Locke, M.A.; and Hoagland, R.E.
Agricultural Research Service September 1996
Reduction of the nitro group in acifluorfen (a
nitrodiphenyl ether herbicide) to aminoacifluorfen is a
major catabolic transformation of this herbicide in
soils, rhizospheres, and pure cultures of certain
bacteria. Aromatic nitroreduction occurs more rapidly
in rhizosphere soils compared to root-free soil, with a
rapid incorporation into unextractable humic soil
components. Factors affecting acifluorfen-
nitroreductase activity in cell suspensions and cell-free
extracts of these bacteria were studied. Microbial
aromatic nitroreductase activity in soils and
rhizospheres can be an important biotransformation in
the degradation of acifluorfen and other nitroaromatic
herbicides.
Bacterial Inoculants of Forage Grasses That
Enhance Degradation of 2-Chlorobenzoic Acid in
Soil
Siciliano, S.D. and Germida, J.J.
Environmental Toxicology and Chemistry v!6:6 p
1098(7) June 1997
A study was conducted to examine the potential of
rhizosphere inoculants to enhance the degradation of
contaminants in soil. 2-Chlorobenzoic acid was used as
the model contaminant, along with 11 bacterial strains
and 16 forage grass species. Results showed that three
of the forage speciesBromus biebersteinii, Elymus
dauricus, and Agropyron riparumgrew well in the
2-chlorobenzoic acid-contaminated soil and also
enhanced the disappearance of the compound. The best
bacterial inoculants proved to be Pseudomonas
aeruginosa strain R75 and P. savastoanoi strain CBS 5.
The inoculation of the forage grasses with either
bacterial strain increased significantly the
11
-------
Abstracts of Phytoremediation Resources
Organic Contaminants
disappearance of 2-chlorobenzoic acid over that of
unplanted controls.
Bioremediation Bacteria to Protect Plants in
Pentachlorophenol-Contaminated Soil
Pfender, W.F.
Journal of Environmental Quality v 25:6 p 1256(5)
November-December 1996
Pseudomonas strain SR3, a known pentachlorophenol-
degrader, was added to a pentachlorophenol-
contaminated soil, and the ability of the bacteria to
protect Proso millet sown in the soil was
assessed. Plants were removed from the soil 28 days
after planting with roots, shoots, and soil analyzed for
pentachlorophenol. Seedling emergence was found to
be 50 and 62% for bacteria-treated and control seeds,
respectively, in pentachlorophenol-contaminated soil.
In uncontaminated soil, emergence rates were 100 and
87%, respectively. Bacterial treatment greatly increased
final plant biomass in contaminated soil, bringing root
and total plant weights to nearly the same as those
observed for plants grown in uncontaminated soil. In
contaminated soil planted with bacteria-treated seeds,
the final pentachlorophenol level was only 3 mg/kg, as
compared to 5 and 157 mg/kg for the millet-only and
nonplanted contaminated soils, respectively.
Decreased Transpiration in Poplar Trees Exposed to
2,4,6-Trinitrotoluene
Thompson, P.L.; Ramer, L.A.; Guffey, A.P.; and
Schnoor, J.L.
Environmental Toxicology & Chemistry v 17:5 p
902(5) May 1998
Poplar trees were exposed to 2,4,6-trinitrotoluene
(TNT), and the effects on transpiration were examined.
The TNT concentrations used were 0, 1, 3, 5, 10, and
15 mg/1. Levels of TNT uptake reached the detection
limit of 4 ppm after only 1 hour of exposure, with TNT
removed at a relatively rapid rate. TNT concentrations
of greater than 5 mg/1 were toxic to the trees, with the
decrease in biomass attributed to the inhibition of leaf
growth. This level decreased transpiration significantly
after 11 days of exposure. Overall, the hybrid poplar
exhibited a tolerance for TNT that was higher than that
of duckweed and similar to that of yellow nutsedge.
Degradation of Polychlorinated Biphenyls by Hairy
Root Culture of Solatium nigrum
Mackova, M; Macek, T.; Kucerova, P.; Burkhard, I;
Pazlarova, I; and Demnerova, K.
Biotechnology Letters v 19:8 p 787(4) August 1997
Hairy root cultures ofSolanum nigrum proved capable
of transforming PCBs under controlled conditions. The
impact of several different plant growth regulators on
cell growth and transformation of PCBs are analyzed.
Plant cells proved capable of transforming PCBs even
after growth had stopped. A 20% reduction in PCB
conversion efficiency was observed in young inoculum
(16 days), as compared against older inocula (37 and
68 days). The PCB transformation rate was stimulated
with increasing size of inoculum.
Detoxification of Phenol by the Aquatic Angiosperm,
Lemna gibba
Barber, J.T.; Sharma, H.A.; Ensley, H.E.; Polito, M.A.;
and Thomas, D.A.
Chemosphere v 31:6 p 3567(8) September 1995
In many cases, plants have the ability to metabolize
organic pollutants by transformation and conjugation
reactions followed by compartmentalizing products in
their tissues. The toxicity and fate of phenol in the
angiosperm Lemna gibba were investigated. Over a 16
day growth period, almost 90% of the applied phenol
disappeared from solution. While the disappearance of
phenol was attributed to plant uptake, the appearance of
additional compounds in the media indicated that
metabolism occurred, with the release of the
metabolites back to the media. The primary metabolite
was identified as phenyl-(gr)b-D-glucoside, which was
found to be approximately half as toxic as the parent
compound.
12
-------
Abstracts of Phytoremediation Resources
Organic Contaminants
Effect of Hybrid Poplar Trees on Microbial
Populations Important to Hazardous Waste
Bioremediation
Jordahl, J.L.; Foster, L.; Schnoor, J.L.; and Alvarez,
P.J.J.
Environmental Toxicology and Chemistry v 16:6 p
1318(4) June 1997
Microbial populations from the rhizosphere of
seven-year-old hybrid poplar trees were characterized
in terms of five specific phenotypes: total heterotrophs;
denitrifiers; pseudomonads; degraders of benzene,
toluene, and xylenes (BTX); and atrazine degraders.
The concentrations of these phenotypes were measured
in three rhizosphere samples and in three control soil
samples taken from an adjacent corn field. All types of
microbial populations were higher in the poplar
rhizosphere than in the surrounding soil. Highest
concentrations were found for total heterotrophs,
followed by denitrifiers, pseudomonads, BTX
degraders, and atrazine degraders. These findings are
discussed in relation to bioremediation potential.
Effects of Ryegrass on Biodegradation of
Hydrocarbons in Soil
Gunther, T.; Friedrich-Schiller-Universitat I;
Dornberger, U.; and Fritsche, W.
Chemosphere v 33:2 p 203(13) July 1996
The influence of ryegrass on the biodegradation of
applied aliphatics and PAHs was investigated using a
series of laboratory soil-column experiments. A defined
mixture of saturated, unsaturated, and branched-chain
aliphatics and PAHs was added to the soil columns.
Results show that the artificially applied aliphatic
hydrocarbons disappeared faster and to a greater extent
in ryegrass-planted columns than in the non-root
systems. The enhanced disappearance of the pollutants
in the rhizosphere was accompanied by higher values
for microbial plate counts and soil respiration rates for
the vegetated systems, which indicated the primary role
of microbial degradation. In contrast to the aliphatics,
the amount of PAHs decreased rapidly in both systems,
and the differences between planted and unplanted soil
were insignificant.
A Field Facility for Phytoremediation Research
Rhykerd, R.L.; Hallmark, M.T.; and Munster, C.L.
The 1998 ASAE Annual International Meeting, 11-16
July 1998, Orlando, Florida
American Society of Agricultural Engineers, St.
Joseph, MI 1998
A recently developed phytoremediation computer
model may be extremely useful in predicting the fate of
recalcitrant hydrocarbons in soil. A field facility for
phytoremediation research has been constructed to
provide empirical data to validate and calibrate the
model. Trinitrotoluene (TNT);
2,2',5,5'-tetrabromobiphenyl (PBB); and chrysene have
been tested. Due to the hazardous nature of these
hydrocarbons, the soil-contaminant mixture was
isolated from the field environment using two lysimeter
designs. Soil in both the box and column lysimeters
were contaminated with 10 mg of each contaminant per
kg of soil. Vegetation treatments consisted of fallow,
warm season grass (Johnsongrass), cool season grass
(Canadian wild-rye grass), and a warm/cool season
grass rotation (Johnsongrass/Canadian wild-rye grass).
Both the box and column lysimeters functioned well in
collecting parameters necessary to validate and
calibrate the computer model.
Greenhouse Evaluation of Agronomic and Crude
Oil-Phytoremediation Potential Among Alfalfa
Genotypes
Wiltse, C. C.; Rooney, W. L.; Chen, Z.; Schwab, A. P.;
and Banks, M. K.
Journal of Environmental Quality v 27:1 p 169(5)
January-February 1998
Twenty alfalfa plants were evaluated in terms of their
agronomic performance and phytoremediation potential
for crude oil-contaminated soil. Among the genotypes,
differences were observed in total forage yield,
maturity, plant height, and leaf-burn rating. Total
petroleum hydrocarbon concentrations in soil after 12
months ranged 3799-5754 mg/kg for soils with the
alfalfa plants and averaged 4610 mg/kg in the
unvegetated control. When each genotype was
considered separately, two genotypes had total
petroleum hydrocarbon concentrations that were
significantly lower than that of the unvegetated control.
Plants growing in contaminated soil, however,
13
-------
Abstracts of Phytoremediation Resources
Organic Contaminants
exhibited later maturation and shorter heights than
those growing in uncontaminated soil.
The Influence of Planting and Soil Characteristics
on Mineralization of 2,4,5-T in Rhizosphere Soil
Boyle, J.J. and Shann, J.R.
Journal of Environmental Quality v 27:3 p 704(6)
May-June 1998
Soils from an abandoned pasture, a forest, and a
floodplain near Cincinnati, OH, were used as substrate
for timothy grass, red clover, and sunflower, and
evaluated in terms of their mineralization of
2,4,5-trichlorophenoxyacetic acid (2,4,5-T). Microbial
activity, biomass, and mineralization of 2,4,5-T in
rhizosphere soil were determined before and after
planting. Results showed that microbial activity and
biomass were dependent upon soil type in the unplanted
plots. In soils with lower values, planting significantly
increased biomass and/or activity, independent of plant
species. Overall, soil type was the most significant
determinant of microbial biomass, activity, and
xenobiotic degradation.
Mineralization of 2,4-Dichlorophenol by
Ectomycorrhizal Fungi in Axenic Culture and in
Symbiosis with Pine
Meharg, A.A.; Cairney, J.W.G.; and Maguire, N.
Chemosphere v 34:12 p 2495(10) June 1997
The fungal mycelium associated with mycorrhizal
plants provides a means of enhancing the volume of
rhizospheric soil compared to bulk soil, which can
enhance soil remediation. Two ectomycorrhizal fungal
speciesSuillus variegatus and Paxillus
involutuswere evaluated in terms of their ability to
degrade 2,4-dichlorophenol in batch culture and in
association with Pinus sylvestris. Results indicate that
2,4-dichlorophenol was readily degraded by both
species, but P. involutus proved to be much more
efficient than S. variegatus. In the presence of pine
seedlings, mycorrhizal symbiosis increased
mineralization by both species, but the increase was
much more dramatic for S. variegatus, which under
these conditions became the more efficient degrader of
2,4-dichlorophenol.
Phytoremediation Experimentation with the
Herbicide Bentazon
Conger, R.M. and Portier, R.J.
Remediation v 7:2 p 19(19) 1997
An experiment was performed on six species of trees to
determine the feasibility of remediating ground water
contaminated with an agricultural herbicide, bentazon,
at a site in southern Louisiana. Fate studies on
bentazon support that it is translocated to the plant
leaves where it is degraded to lower-order derivative
compounds within short periods of time. Both
transpiration observations and dosing tests suggest that
both the most favorable phreatophyte and species
tolerant of bentazone exposure was the black willow
(Salix nigra).
Phytoremediation: Modeling Removal of TNT and
Its Breakdown Products
Medina, V.F. and McCutcheon, S.C.
Remediation v 7:1 p 31(15) Winter 1996
The success of phytoremediation techniques for the
treatment of TNT-contaminated ground water and
wastewater is evaluated. Two different
phytoremediation techniques are examined: controlled
reactors and constructed wetlands. The benefits offered
by controlled reactors include: greater control over
operating parameters, reduced chances of contaminant
migration, and reduced chances that animals will feed
on the plants. Constructed wetlands are generally less
expensive and often provide aesthetic and ecological
benefits. A first-order, nonreversible reaction,
plug-flow, finite-difference model was used to predict
the disappearance of TNT from a constructed wetland.
Phytoremediation of 1,4-dioxane by Hybrid Poplars
Aitchison, E.W.; Schnoor, J.L.; Kelley, S.L.; and
Alvarez, P.J.J.
Proceedings of the 12th Annual Conference on
Hazardous Waste Research, 20-22 May 1997, Kansas
City, Missouri
The suspected carcinogen 1,4-dioxane has a half-life in
soils and ground water of several years, while its
half-life in the atmosphere in the presence of NO and
14
-------
Abstracts of Phytoremediation Resources
Organic Contaminants
hydroxyl radicals is several hours. The researchers
examine 1,4-dioxane volatilization into the atmosphere
via plant transpiration, evaluating the capacity of
rooted cuttings of hybrid poplar trees to take up and
translocate 1,4-dioxane. Study results indicate that
poplar uptake of 1,4-dioxane far exceeds its
degradation by indigenous root-zone microorganisms.
The majority of 1,4-dioxane taken up into the plant was
volatilized, with the remaining mass concentrated
primarily in the stem. Rapid uptake of 1,4-dioxane by
hybrid poplar trees makes phytoremediation an
attractive treatment alternative at
dioxane-contaminated sites, and research into this
treatment methodology will continue.
Phytoremediation of Hazardous Wastes
McCutcheon, S.C.; Wolfe, N.L.; Carreria, L.H.; and
Ou, T.Y.
Innovative Technologies for Site Remediation and
Hazardous Waste Management: Proceedings of the
National Conference, 23-26 July 1995, Pittsburgh,
Pennsylvania
American Society of Civil Engineers, New York, NY p
597(8) 1995
Analyzing the effectiveness of phytoremediation
involves rigorous pathway analyses, mass balance
determinations, and identification of specific enzymes
that break down trinitrotoluene (TNT), other explosives
(RDX and HMX), nitrobenzene, and chlorinated
solvents (such as TCE and PCE). For example, TNT is
completely and rapidly degraded by nitroreductase and
laccase enzymes. As part of the natural lignification
process, the aromatic ring is broken and the carbon in
the ring fragments is incorporated into new plant fiber.
The use of created wetlands and other
phytoremediation applications guided by rigorous field
biochemistry and ecology promises to be a vital part of
a newly evolving field, ecological engineering.
Phytoremediation of Organic Contaminants: A
Review of Phytoremediation Research at the
University of Washington
Newman, L.A.; Doty, S.L.; Gery, K.L.; Heilman, P.E.;
etal.
Journal of Soil Contamination, v 7:4, p 531(12), 1998
Studies to determine the potential for phytoremediation
of fully chlorinated compounds, brominated
compounds, and nonhalogenated compounds are
underway. When using phytoremediation, it is
important to select not only a plant that is capable of
degrading the pollutant in question, but also one that
will grow well in that specific environment. One way to
supplement the arsenal of plants available for remedial
actions is to utilize genetic engineering tools to insert
into plants those genes that will enable the plant to
metabolize a particular pollutant. Hybrid technologies,
such as using plants in pumping and irrigation systems,
also enable plants to be used as a remedial method
when the source of the pollutant is beyond the reach of
plant roots, or when planting space directly over the
pollutant is unavailable or restricted. Thus, the
potential uses of phytoremediation are expanding as the
technology continues to offer new, low-cost remediation
options.
Phytoremediation of Pesticide-Contaminated Soils
Kruger, E.L.; Anderson, T.A.; and Coats, J.R.
Air & Waste Management Association's 89th Annual
Meeting, 1996, Nashville, Tennessee
Available at http://www.awma.org
Screening tests of rhizosphere soils from 15 plant
species were conducted to determine their ability to
mineralize two common herbicide contaminants:
atrazine and metolachlor. Mineralization of
14C-atrazine or 14C-metolachlor, applied at 50 ppm
each, was monitored. Kochia rhizosphere soil exhibited
the greatest mineralization of 14C-atrazine. Other
rhizosphere soils that exhibited the ability to mineralize
high concentrations of atrazine included musk thistle,
catnip, foxtail barley, witchgrass, and lambsquarters.
None of the rhizosphere soils tested exhibited a positive
response for 14C-metolachlor mineralization.
Mineralization of atrazine was considerable after 36
days, while mineralization of metolachlor was minimal.
The percentage of extractable atrazine for kochia
vegetated soils was significantly less than from
nonvegetated soil. Combustion of plants revealed that
11% of the applied 14C was taken up by kochia. This
research indicates that the use of plants in remediating
soils looks promising.
15
-------
Abstracts of Phytoremediation Resources
Organic Contaminants
Phytoremediation of Trichloroethylene with Hybrid
Poplars
Gordon, M; Choe, N.; Duffy, I; Ekuan, G.; Heilman,
P.; Muiznieks, I.; Newman, L.; Ruszaj, M.; Shurtleff,
B.B.; Strand, S.; and Wilmoth, J.
Phytoremediation of Soil and Water Contaminants
American Chemical Society, Washington, DC p 177(9)
1997
The ability of hybrid plants to absorb trichloroethylene
(TCE) from ground water was examined. Initial studies
used axenic tumor cultures of HI 1-11 grown in the
presence of 14C-TCE. These cells metabolized the TCE
to produce trichloroethanol, di- and trichloroacetic
acid. Some of the TCE was incorporated into insoluble,
non-extractable cell residue, and small amounts were
mineralized to 14C-CO2. Rooted poplar cuttings grown
in PVC pipes produced the same metabolites when
exposed to TCE. Mass balance studies indicate that the
poplars also transpire TCE. In addition one of the first
controlled field trials for this technology is being
conducted. Trees were planted in cells lined with high
density polyethylene and exposed to TCE via an
underground water stream during the growing season.
Cells containing trees had significantly reduced TCE
levels in the effluent water stream compared to control
cells containing only soil. These results show that
significant TCE uptake and degradation occur in
poplars.
Phytoremediation, Plant Uptake of Atrazine and
Role of Root Exudates
Burken, J.G. and Schnoor, J.L.
Journal of Environmental Engineering v 122:11 p
958(6) 1996
The potential of phytoremediation in the cleanup of
contaminated sites and prevention of non-point-source
pollution was examined with the pesticide atrazine in
two experimental systems. Uptake was determined in
batch experiments with 14C ring-labeled atrazine and
hybrid poplar trees grown in two soil types.
Mineralization was studied utilizing soil microcosms
with the addition of root exudates. Results indicate that
poplar cuttings were able to uptake the majority of
applied atrazine that was not tightly sorbed to the
organic fraction of the soil, with no detectable adverse
effects to the trees. The addition of root exudate to
microcosms showed slight stimulation and the addition
of ground-up root biomass revealed large stimulation of
mineralization to 14CO2. This research indicates that
vegetative uptake and degradation in the rhizosphere
can play a major role in remediation at hazardous waste
sites.
Phytotreatment of TNT-Contaminated Groundwater
Rivera, R.; Medina, V.F.; Larson, S.L.; and
McCutcheon, S.C.
Journal of Soil Contamination, v 7:4, p 511(20), 1998
Phytoremediation is a viable technique for treating
munitions-contaminated ground water and wastewater.
Continuous flow reactor studies were conducted at three
different influent concentrations of 2,4,6-trinitrotoluene
(TNT): 1,5, and 10 ppm. Retention times varied from
12 to 76 days. Batch experiments were conducted to
confirm the phytodegradation of amino-derivatives of
TNT. Plant tissue was analyzed for TNT and
breakdown products. Preliminary batch studies were
also conducted on the degradation of RDX. Initially,
the control removed TNT as efficiently as the plant
reactors. However, as time continued, the efficiency of
the control dipped below that of the plant reactors,
suggesting that adsorption was initially the mechanism
of removal. Up to 100% of the TNT was removed.
Batch studies found that ADNT and
diaminonitrotoluene (DANT) were phytodegraded. The
batch studies indicated that the degradation of RDX
was slower than that for TNT. Different plants were
more efficient at removing RDX than those for
removing TNT, suggesting that there are differences in
the removal mechanisms.
Plant Cell Biodegradation of a Xenobiotic Nitrate
Ester, Nitroglycerin
Goel, A.; Kumar, G.; Payne, G.F.; and Dube, S.K.
Natural Biotechnology v 15:2 p 174(4) 1997
The ability of plants to metabolize glycerol trinitrate
(GTN, nitroglycerin), was examined using cultured
plant cells and plant cell extracts. Intact cells rapidly
degrade GTN with the initial formation of glycerol
dinitrate (GDN) and the later formation of glycerol
mononitrate (GMN). Cell extracts were shown to be
16
-------
Abstracts of Phytoremediation Resources
Organic Contaminants
capable of degrading GTN with the simultaneous
formation of GDN in stoichiometric amounts. The
degradative activities of plant cells are only ten times
less than those reported for bacterial GTN degradation.
These results suggest that plants may serve a direct
degradative function for the phytoremediation of sites
contaminated by organic nitrate esters.
Plant-Enhanced Remediation of Petroleum
Contaminated Soil
Novak, J.T. and Al-Ghazzawi, Z.
Proceedings of the 1997 29th Mid-Atlantic Industrial
and Hazardous Waste Conference
Technomic Publishing Co., Lancaster, PA p 605(9)
1997
Phytoremediation is an easy and inexpensive method
for treating petroleum-contaminated soils. The
phytoremediation mechanism is related to direct
contaminant uptake or indirect plant mechanisms
which catalyze pollutant-microbe interaction in the
rhizosphere. These mechanisms and their importance
are studied.
Plant-Enhanced Subsurface Bioremediation of
Nonvolatile Hydrocarbons
Chang, Y.Y. and Corapcioglu, M.Y.
Journal of Environmental Engineering v 124:2 p
162(8) February 1998
Phytoremediation has become a promising new area of
research for in situ cleanup of large volumes of slightly
contaminated soils. A model that can be used as a
predictive tool in phytoremediation operations was
developed to simulate the transport and fate of a
residual hydrocarbon contaminant interacting with
plant roots in a partially saturated soil. Time-specific
distribution of root quantity through soil, as well as root
uptake of soil water and hydrocarbon, was incorporated
into the model. In addition, the microbial activity in the
soil rhizosphere was modeled with a biofilm theory.
The simulation results showed enhanced
biodegradation of a hydrocarbon contaminant mostly
because of increased biofilm metabolism of organic
contaminants in a growing root system of cotton.
Simulations also show that a high mean daily
root-water uptake rate increases the contaminant
retardation factors because of the resulting low water
content. The ability to simulate the fate of a
hydrocarbon contaminant is essential in designing
technically efficient and cost-effective, plant-aided
remedial strategies and in evaluating the effectiveness
of a proposed phytoremediation scheme.
Potential of Phytoremediation as a Means for
Habitat Restoration and Cleanup of Petroleum
Contaminated Wetlands
Lin, Q. and Mendelssohn, A.
Phytoremediation of Soil and Water Contaminants
American Chemical Society, Washington, DC 1997
Oil spills in coastal wetlands often kill vegetation and
contaminate wetland sediment for many years. The
potential of phytoremediation for habitat restoration
and cleanup of contaminated marshes was studied with
marsh mesocosms. Soil sods of Spartina alterniflora
and Spartina patens (common coastal marsh grasses)
were dosed with crude oil. Two years after application
of the oil to the soil sods, these two Spartina species
were transplanted into oiled and unoiled sods to
determine the potential for habitat restoration and oil
phytoremediation. The regrowth biomass was not
significantly affected by oil for combined biomass of
the two species and significantly higher with oil for
Spartina alterniflora, suggesting the potential for
habitat restoration by transplanting after oil spills. Oil
degradation was enhanced by phytoremediation in
combination with fertilization. The oil degradation rate
was negligible in the absence of vegetation, but it was
significantly higher in the presence of transplanted
vegetation and fertilizer. Whether increased
degradation of residual oil was due to the enhancement
of soil microbial activity by the fertilizer or by
phytoremediation is presently being investigated.
Rhizosphere Microbial Populations in Contaminated
Soils
Nichols, T.D.; Wolf, D.C.; Rogers, H.B.; Beyrouty,
C.A.; and Reynolds, C.M.
Water, Air, and Soil Pollution v 95:1-4 p 165(14) 1997
17
-------
Abstracts of Phytoremediation Resources
Inorganic Contaminants
Rhizosphere microbial populations may enhance
bioremediation of soil contaminated with organic
chemicals. A growth chamber study was conducted to
evaluate rhizosphere microbial populations in
contaminated and non-contaminated soil. Alfalfa
(Medicago sativa L.) and alpine bluegrass (Poa alpina
L.) were grown in soil containing a mixture of organic
chemicals for 14 weeks. The equal mixture of
hexadecane, (2,2-dimethylpropyl)benzene,
cis-decahydronaphthalene (decalin), benzoic acid,
phenanthrene, and pyrene was added at levels of 0 and
2000 mg/kg. At nine weeks, the organic chemical
degrader (OCD) populations were significantly higher
in rhizosphere and contaminated soils than in bulk and
non-contaminated soils. Selective enrichment of OCD
populations was observed in contaminated rhizosphere
soil. Higher numbers of OCD in contaminated
rhizospheres suggest potential stimulation of
bioremediation around plant roots.
Transformation of TNT by Aquatic Plants and Plant
Tissue Cultures
Hughes, J. B.; Shanks, I; Vanderford, M; Lauritzen,
I; andBhadra, R.
Environmental Science & Technology v 31:1 p 266(6)
1997
The ability of plants to uptake and transform
2,4,6-trinitrotoluene (TNT) was investigated using the
aquatic plants Myriophyllum spicatum, axenic
Myriophyllum aquaticum, and Catharanthus roseus
hairy root cultures. Studies demonstrate that both
Myriophyllum and C. roseus transform TNT. Primary
products of transformation were not identified, and
mineralization was not observed. Mass balances
demonstrate that a large percentage of the unknown
TNT transformation products were associated with the
plant. This fraction could be at least partially recovered
from the plant tissue with methanol extraction. A
soluble fraction was also present in the medium. The
formation of soluble, uncharacterized transformation
products is a concern for potential phytoremediation
applications.
Uptake and Fate of Organohalogens from
Contaminated Groundwater in Woody Plants
Sytsma, L.; Mulder, J.; Schneider, J.; et al.
Proceedings of the 213th National Meeting of the
American Chemical Society, 13-17 April 1997, San
Francisco, California
American Chemical Society, Washington, DC p 89
1997
Phytoremediation uses green plants for low-cost,
low-tech remediation processes in which selected plants
and natural or engineered microorganisms work
together to metabolize, convert, absorb, accumulate,
sequester, or otherwise render harmless multiple
environmental contaminants. There is evidence that
plants can degrade a portion of many organic
contaminants and form less volatile compounds which
are sequestered in the plant tissue. The remainder of
the contaminant is passed out of the leaf tissue with the
transpiration stream. Hybrid poplar plants fed by TCE-
and PCE-spiked nutrient solutions in a greenhouse
showed elevated degradation product levels in the
leaves within a week, as well as evidence for
evapotranspiration of the TCE and PCE.
Publications Containing Multiple Papers
Bioremediation and Phytoremediation: Chlorinated
and Recalcitrant Compounds: the First
International Conference on Remediation of
Chlorinated and Recalcitrant Compounds,
Monterey, California, May 18-21,1998
Wickramanayake, G.B. and Hinchee, R.E. (eds.)
Battelle Press, Columbus, OH 301 pp 1998
Inorganic Contaminants
Overviews
Emerging Technologies for the Remediation of
Metals in Soils: Phytoremediation
Interstate Technology and Regulatory Cooperation
Work Group (ITRC), Metals in Soils Work Team 15 pp
1998
Available at http://www.sso.org/ecos/itrc
Phytoremediation is a means of removing organic or
inorganic contaminants from soils, sediments, and
ground water using plants. This document focuses on
18
-------
Abstracts of Phytoremediation Resources
Inorganic Contaminants
issues related to the remediation of metals in soils. The
technology, its applicability to sites and contaminants,
and associated costs are outlined. Several approaches to
phytoremediation are explored. The document also
presents regulatory and stakeholder concerns and
discusses research needs.
Literature Review: Phytoaccumulation of
Chromium, Uranium, and Plutonium in Plant
Systems
Hossner, L.R.; Loeppert, R.H.; Newton, R.J.; and
Szaniszlo, P.J.
Amarillo National Resource Center for Plutonium, TX
53 pp May 1998
Phytoremediation is an integrated approach to the
cleanup of contaminated soils that combines the
disciplines of plant physiology, soil chemistry, and soil
microbiology. Removal of metals from contaminated
soils using accumulator plants is the goal of
phytoremediation. The emphasis of this review has
been placed on chromium (Cr), plutonium (Pu), and
uranium (U). With the exception of Cr, these metals
and their decay products exhibit two problems:
radiation dose hazards and their chemical toxicity.
Radiation dose hazards introduce the need for special
precautions in reclamation beyond that associated with
non-radioactive metals. The uptake of metals by plants
occurs predominantly by way of channels, pores, and
transporters in the root plasma membrane. Most
vascular plants absorb toxic and heavy metals through
their roots to varying degrees.
Remediation of Metal-Contaminated Sites Using
Plants
Azadpour, A. and Matthews, J.E.
Remediation v 6:3 p 1(18) 1996
The current technologies employed for removal of
heavy metals from soils often involve expensive ex situ
processes requiring sophisticated equipment for
removal, transportation, and purification of the soil. In
situ bioremediation is receiving increasing attention
because of its relative effectiveness and low cost.
Phytoremediation, a new type of bioremediation, uses
metal-tolerant hyperaccumulator plants to take up
metal ions from soils and store them in the plant itself.
To select the appropriate phytoremediation technology,
the technical feasibility, cost effectiveness, and
availability of the suitable plant species must be
examined. Before phytoremediation can be exploited on
a contaminated site, greenhouse-scale confirmatory
testing is necessary to measure plant uptake and
correlate shoot metal concentrations to available soil
metals. These tests also validate that the harvesting and
subsequent disposal of metal-containing plant tissues
are environmentally safe and manageable.
Restoration of Mined LandsUsing Natural
Processes
Bradshaw, A.
Ecological Engineering v 8:4 p 255(15) August 1997
In many countries legislation now requires that surface
soils disturbed by mining activities be conserved and
replaced, but there is a vast heritage of contaminated
land left by past mining. The processes of natural
succession demonstrate that unaided restoration can be
achieved along with the development of fully
functioning soils. Plants can readily provide organic
matter, lower soil bulk density, bring mineral nutrients
to the surface, and accumulate them in an available
form. Most importantly, some species can fix and
accumulate nitrogen rapidly in quantities more than
adequate for normal ecosystem functioning. Certain
extreme soil conditions may occur that prevent plant
growth, particularly physical conditions, gross lack of
certain nutrients, and toxicity. However, ecosystem
restoration can be achieved at low cost, and the product
be self-sustaining in the long term.
Status of In Situ Phytoremediation Technology
U. S. EPA, Office of Solid Waste and Emergency
Response
Published in Recent Developments for In Situ
Treatment of Metal Contaminated Soils p 31(12)
| EPA Document Number: EPA 542-R-97-004
This chapter offers an overview of different
phytoremediation approaches: phytoextraction,
19
-------
Abstracts of Phytoremediation Resources
Inorganic Contaminants
phytostabilization, and rhizofiltration, as well as a
performance and cost summary, applications and future
development analyses, and a list of metal
hyperaccumulating plants.
Field Studies and Demonstrations
Phytoaccumulation of Trace Elements by Wetland
Plants: /. Duckweed
Zayed, A.; Gowthaman, S.; and Terry, N.
Journal of Environmental Quality v 27:3 p 715(7)
May-June 1998
The removal of trace elements by wetland vegetation is
enhanced by the use of appropriate plant species.
Results are presented from the first in a series of
wetland-plant evaluations in terms of the removal of
trace elements from contaminated water. Duckweed
was considered for its phytoaccumulation of cadmium
(Cd), chromium (Cr), copper (Cu), lead (Pb), nickel
(Ni), and selenium (Se). The data show that Cd was
accumulated to the greatest levels, followed by Se, Cu,
and Cr, and then Pb and Ni.
Relationship Between Sulfur Speciation in Soils and
Plant Availability
Shan, X.-Q.; Chen, B.; Zhang, T.-H.; Li, F.-L.; Wen,
B.; andQian, J.
Science of the Total Environment v 199:3 p 237(10)
1997
Both bench-scale experiments and field surveys were
conducted to investigate the relationship between sulfur
speciation in soils and sulfur concentration in plants.
Soil sulfur was fractionated into water-soluble sulfate
(SO, adsorbed sulfate (S2), carbonate-occluded sulfate
(S3), ester sulfate (S4) and carbon-bonded sulfur (S5).
Water-soluble sulfate was the most easily available
form of soil sulfur, followed by adsorbed sulfate, ester
sulfate, carbon-bonded sulfur and carbonate-occluded
sulfate. Changes in concentrations of the different
forms of soil sulfur after bench-scale experiments gave
direct evidence to the order of availability. Sj and S2
decreased significantly, S4 also decreased, whereas S5
and S3 remained almost unchanged. These results
suggest that water-soluble and adsorbed sulfate are
directly available to plants, while the mineralization of
sulfate from organic sulfur, especially from ester
sulfate, also contributes to plant uptake of sulfur.
Removal of Uranium from Water Using Terrestrial
Plants
Dushenkov, S.; Vasudev, D.; Kapulnik, Y.; Gleba, D.;
Fleisher, D.; Ting, K.C.; and Ensley, B.
Environmental Science & Technology v 31:12 p
3468(6) December 1997
Uranium (U) contamination of ground water poses a
serious environmental problem in uranium mining
areas and in the vicinity of nuclear processing facilities.
Preliminary laboratory experiments and treatability
studies indicate that the roots of terrestrial plants can be
efficiently used to remove U from aqueous streams
(rhizofiltration). Almost all of the U removed from the
water in the laboratory using sunflower plants was
concentrated in the roots. Rhizofiltration technology
has been tested in the field with U-contaminated water
at concentrations of 21874 ^g/L at a former U
processing facility in Ashtabula, OH. The pilot-scale
rhizofiltration system provided final treatment to the
site source water and reduced U concentration to <20
/ug/L before discharge to the environment. System
performance was subsequently evaluated under
different flow rates permitting the development of
effectiveness estimates for the approach.
Research
Differences in Root Uptake of Radiocesium by 30
Plant Taxa
Broadley, M.R. and Willey, N.J.
Environmental Pollution v 97:1-2 p 11(5) 1997
The concentration of Cesium (Cs) was measured in the
shoots of 30 plant taxa after exposing the roots to 0.1
/-ig/g radiolabelled Cs soil for 6 hours. The maximum
accumulation differences were between Chenopodium
quinoa and Koeleria macrantha (20-fold in Cs
concentration and 100-fold in total Cs accumulated).
The lowest Cs concentrations occurred in slow growing
Gramineae and the highest in fast growing
Chenopodiaceae. If radiocesium uptake by the
Chenopodiaceae during chronic exposures shows
similar patterns to those reported here after acute
20
-------
Abstracts of Phytoremediation Resources
Inorganic Contaminants
exposure, then the food contamination implications and
the potential for phytoremediation of radiocesium
contaminated soils using plants in this family may be
worth investigating.
Enhanced Accumulation of Pb in Indian Mustard by
Soil-Applied Chelating Agents
Blaylock, M.J.; Salt, D.E.; Dushenkov, S.; Zakharova,
O.; Gussman, C.; Kapulnik, Y.; Ensley, B.D.; and
Raskin, I.
Environmental Science & Technology v 31 p 860(6)
1998
Phytoremediation is emerging as a potential cost-
effective solution for the remediation of contaminated
soils. Because contaminants such as lead (Pb) have
limited bioavailability in the soil, a means of
solubilizing Pb in the soil and facilitating its transport
to plant shoots is vital to the success of
phytoremediation. Indian mustard (Brassica juncea)
was used to demonstrate the capability of plants to
accumulate high tissue concentrations of Pb when
grown in Pb-contaminated soil. A concentration of
1.5% Pb in the shoots of B. juncea was obtained from
soils containing Pb (600 mg/kg) amended with
synthetic chelates such as EDTA. The accumulation of
Pb in the tissue
corresponded to the concentration of Pb in the soil and
the concentration of EDTA added to the soil. The
accumulation of Cadmium, Copper, Nickel, and Zinc
from contaminated soil amended with EDTA and other
synthetic chelators was also demonstrated. The research
indicates that the accumulation of metals in the shoots
of B. juncea can be enhanced through the application of
synthetic chelates to the soil, facilitating high biomass
accumulation as well as metal uptake.
Evaluation of Tamarisk and Eucalyptus
Transpiration for the Application of
Phytoremediation
Tossell, R.W.; Binard, K.; Sangines-Uriarte, L.;
Rafferty, M.T.; and Morris, N.P.
Bioremediation and Phytoremediation: Chlorinated
and Recalcitrant Compounds
Battelle Press, Columbus, OH p 257(6) 1998
A greenhouse study was conducted to evaluate
phytoremediation using tamarisk and eucalyptus at a
site in East Palo Alto, CA, where the ground water was
contaminated with arsenic. The initial study assessed
whether the trees could tolerate arsenic and sodium
found in the ground water and soil. Over the course of
the study, tamarisk used significantly more water than
eucalyptus, but eucalyptus water use was substantially
higher than tamarisk when normalized to shoot mass.
Water use by both species was substantially lower for
trees exposed to high sodium treatments, but tamarisk
was less affected than eucalyptus.
Feasibility of Using Plants to Assist in the
Remediation of Heavy Metal Contamination at
J-Field, Aberdeen Proving Ground, Maryland. Final
Report
Jastrow, J.D.
29 pp November 1995
Interest in the development of in situ bioremediation
technologies has grown substantially over the last
decade. The purpose of this project was to investigate
the potential for using plants to remediate soils
contaminated with heavy metals. Phragmites australis,
one of the dominant species in the Toxic Burning Pits
(TBP) area and other contaminated sites within J-Field,
appears to be both tolerant of heavy metal contaminated
soil conditions and capable of producing large amounts
of biomass. Consequently, this project has concentrated
on characterizing heavy metal accumulation by
Phragmites australis growing in the TBP area relative
to soil concentrations and availabilities. This type of
information is necessary to determine the feasibility of
using this species to assist in the remediation of metal
contaminated soils at J-Field.
Lead-Contaminated Sediments Prove Susceptible to
Phytoremediation
Goldsmith, W.
5*0/7 and Groundwater Cleanup p 15(3)
February/March 1998
[Also available at http://www.bioengineering.com
under the title Phytoremediation Potential for Lead-
Contaminated River Sediments]
21
-------
Abstracts of Phytoremediation Resources
Inorganic Contaminants
Most conventional technologies for removal or capping
of lead-contaminated river sediments are neither
technically nor economically practicable. Engineered
wetlands for removal of lead from riverine sediments
appear to offer a sound approach to cleanup via
phytoextraction followed by harvesting. Plants have
been identified that grow in this type of environment
and possess a documented ability to take up lead into
leaves, roots, and stems. Recent research suggests that
phytoremediation conducted over a period of years can
offer significant benefits in sediment cleanup.
Lead Uptake and Effects on Seed Germination and
Plant Growth in a Pb Hyperaccumulator Brassica
pekinensis Rupr.
Xiong, Z.-T.
Bulletin of Environmental Contamination Toxicology v
60:2 p 285(7) February 1998
The ability of Brassica pekinensis Rupr. to
hyperaccumulate lead could make it effective for the
phytoremediation of contaminated soils. The effect of
various concentrations of lead on the germination of
seeds and growth of plants was investigated. Generally
germination and growth of roots and shoots
demonstrated dose-related inhibition. Bioaccumulation
of lead in root, stem, and leaf was related to lead
concentration in the growth medium. Roots
bioconcentrated lead to between 27 and 34 times the
concentration in growth medium. Stem and leaf
bioconcentration ranged from four to seven times and
two to three times, respectively. The shoot to root ratio
of lead was 0.9 for this plant species, which compares
well with other hyperaccumulators. High ratios allow
lead concentrated in shoots to be easily removed by
harvesting.
Metal Accumulation by Aquacultured Seedlings of
Indian Mustard
Salt, D.E.; Pickering, I.J.; Prince, R.C.; Gleba, D.;
Dushenkov, S.; Smith, R.D.; and Raskin, I.
Environmental Science & Technology v 31 p 1636(9)
1997
Indian mustard (Brassica juncea (L.) Czern) seedlings
grown in aerated water were able to accumulate various
metals from contaminated water over a range of
environmentally relevant metal concentrations.
Seedlings concentrated the divalent cations Lead(II),
Strontium(II), Cadmium(II), and Nickel(II) 500-2000
times and concentrated monovalent Cesiumฎ and
hexavalent Chromium(IV) 100-250 times from
contaminated water containing the competing ions Ca,
Mg, K, SO4, and NO3. At the lowest Cadmium (Cd)
concentration studied, Cd levels were reduced to below
10 ppb (,wg/L). In the absence of competing ions, Cd
accumulation in seedlings increased 47-fold. This
suggests that a better understanding of the biological
processes governing uptake and accumulation of Cd by
seedlings should allow the application of modern
genetic engineering techniques to improve their
selectivity and capacity for Cd removal from waters
containing high levels of competing ions. As a first step
in this process, we have started to define the tissue and
cellular localization of Cd, its accumulation rates and
possible uptake mechanisms, and the role of
intracellular chelates in Cd detoxification. Intracellular
Cd accumulation in seedlings was mediated by
saturable transport system(s) and inhibited
competitively in shoots and non-competitively in roots
by Ca2+, Zn2+, and Mn2+. Phytochelatins, the Cd-binding
peptides known to be involved in Cd resistance in
mature plants, also accumulated in B. juncea seedlings
exposed to Cd. Our results suggest that the use of
aquacultured seedlings of B. juncea could provide a
novel approach to the treatment of various metal-
contaminated waste streams.
Phytoextraction of Cadmium and Zinc from a
Contaminated Soil
Ebbs, S.D.; Lasat, M.M.; Brady, D.J.; Cornish, I;
Gordon, R.; and Kochian, L.V.
Journal of Environmental Quality v 26:5 p 1424(7)
September-October 97
The phytoextraction ability of Brassica juncea, B.
napus, and B. rapa toward cadmium (Cd) and zinc
(Zn) in a contaminated soil was determined and
compared to that exhibited by Thlaspi caerulescens,
Agrostis capillaris, and Festuca rubra. Results showed
that T. caerulescens achieved shoot Cd concentrations
approximately ten times as great as those of the three
Brassica species, while shoot Zn concentrations in T.
caerulescens were approximately 2.5 times as great.
22
-------
Abstracts of Phytoremediation Resources
Inorganic Contaminants
However, due to the significantly greater biomass
produced by the Brassica species, this species was more
effective in removing Zn and equally effective in
removing Cd as T. caerulescens.
Phytoextraction of Zinc by Oat (Avena saliva),
Barley (Hordeum vulgare), and Indian Mustard
(Brassica juncea)
Ebbs, S.D.; andKochian, L.V.
Environmental Science & Technology v 32:6 802(5)
1998
The success of phytoremediation depends on the
selection of plant species and soil amendments that
maximize contaminant removal. Indian mustard
(Brassica juncea) has been shown to be effective in
phytoextracting Zn, particularly after the synthetic
chelate EDTA has been applied to the soil. However,
the effectiveness of grass species for phytoremediation
has not been addressed in great detail. A hydroponic
screening of 22 grass species indicated that oat (Avena
sativa) and barley (Hordeum vulgare) tolerated the
high copper, cadmium, and zinc concentrations present
in the solution and also accumulated elevated
concentrations of these metals in the plant shoots. A
hydroponic experiment comparing these two grasses to
Indian mustard indicated that, although shoot Zn
concentrations were greater for Indian mustard, the
grasses were considerably more tolerant. The results of
this experiment suggest that barley has a
phytoremediation potential equal to, if not greater than,
that for B. juncea.
Phytoextraction: the Use of Plants to Remove Heavy
Metals from Soils
Kumar, P. B. A. N.; Dushenkov, V.; Motto, H.; and
Raskin, I.
Environmental Science & Technology v 29:5 p 1232(7)
May 1995
The process of phytoextraction, the use of plants to
remove heavy metals from soils, generally requires the
translocation of heavy metals to the easily harvestable
shoots. Several cultivars of Indian mustard (Brassica
juncea) were investigated for their ability to efficiently
accumulate lead and other heavy metals. The Brassica
species included B. nigra, B. oleracea, B. campestris,
B. carinata, B. juncea, and B. napus. Results indicate
that B. juncea and B. nigra had the highest
metal-accumulating ability among the species tested.
Shoot growth was only slightly affected by exposure to
lead over the concentration range tested. For the other
metals examined, chromium had the highest
phytoextraction coefficient, followed by cadmium,
nickel, zinc, and copper.
Phytofiltration of Hazardous Cadmium, Chromium,
Lead and Zinc Ions by Biomass of Medicago sativa
(Alfalfa)
Gardea-Torresdey, J.L.; Gonzalez, J.H.; Tiemann, K.J.;
Rodriguez, O.; and Gamez, G.
Journal of Hazardous Materials v 57:1-3 p 29(11)
1998
Previous laboratory batch experiments of Medicago
sativa (Alfalfa) indicated that the African shoots
population had an appreciable ability to bind copper(II)
and nickel(II) ions from aqueous solution. Batch
laboratory pH profile, time dependency, and capacity
experiments were performed to determine the binding
ability of the African shoots for cadmium(II),
chromium(III), chromium(VI), lead(II), and zinc(II).
Batch pH profile experiments indicate that the optimum
pH for metal binding is approximately 5.0. Time
dependency experiments demonstrate that metal
binding to the African alfalfa shoots occurred within 5
minutes. Binding capacity experiments revealed the
following amounts of metal ions bound per gram of
biomass: 7.1 mg Cd(II), 7.7 mg Cr(III), 43 mg Pb(II),
4.9 mg Zn(II), and 0 mg Cr(VI). The results from these
studies will be useful in the use of phytofiltration to
remove and recover heavy metal ions from aqueous
solution.
Phytoremediation of a Radiocesium-Contaminated
Soil: Evaluation of Cesium137 Bioaccumulation in the
Shoots of Three Plant Species
Lasat, M.M.; Fuhrmann, M.; Ebbs, S.D.; Cornish, J.E.;
and Kochian, L.V.
Journal of Environmental Quality v 27:1 p 165(5)
January-February 1998
23
-------
Abstracts of Phytoremediation Resources
Inorganic Contaminants
At Brookhaven National Laboratory's Hazardous Waste
Management Facilities, the potential for cesium-137
(137Cs) extraction from contaminated soil by three plant
species was studied. In addition, the effect of applying
ammonium nitrate to contaminated soil on 137Cs
extraction was evaluated. The plants used were Indian
mustard, red root pigweed, and tepary bean. Results
show that red root pigweed concentrated the highest
level of 137Cs in shoots, followed by Indian mustard and
tepary bean. Red root pigweed also produced
significantly more shoot biomass than the other two
species. Ultimately, red root pigweed removed 30- to
60-fold more 137Cs from the soil than either of the other
two species. For red root pigweed and tepary bean, the
addition of ammonium nitrate produced only a slight
increase in the level of 137Cs in shoots.
Phytoremediation of Lead-Contaminated Soils: Role
of Synthetic Chelates in Lead Phytoextraction
Huang, J.W.; Chen, I; Berti, W.R.; and Cunningham,
S.D.
Environmental Science & Technology v 31:3 p 800(6)
March 1997
Studies have shown that lead (Pb) is accumulated in the
roots of plants if Pb is bioavailable in the growth
media. However, Pb bioavailability is limited. The
relative efficiencies of selected synthetic chelates in
enhancing Pb phytoextraction were compared. Corn,
pea, goldenrod, sunflower, and ragweed were used, in
combination with the chelates, EDTA, HEDTA, DTP A,
EOT A, and EDDHA. Results show that Pb in soil
solution increased linearly with increasing levels of
HEDTA added to a Pb-contaminated soil. In all plant
species tested, there was a surge in shoot Pb
concentrations in response to the application of
HEDTA, with the highest shoot Pb concentrations
found in pea, followed by corn and sunflower. When
experiments were continued with pea and corn plants,
Pb accumulation was highest in the presence of EDTA,
followed in decreasing order by HEDTA, DTP A,
EOT A, and EDDHA. The rank in the efficiency in
enhancing total Pb accumulation in shoots was the
same as that found in enhancing soil Pb desorption.
Phytoremediation of Selenium Laden Soils: A New
Technology
Banuelos, G.S.; Ajwa, H.A.; Terry, N.; and Zayed, A.
Journal of Soil and Water Conservation v 52:6 p
426(5) November-December 1997
Selenium (Se) is naturally present in many soils around
the U.S. High concentrations of Se may exert toxic
impacts on plants and animals. The performance of
several plant species (including canola, Indian mustard,
birdsfoot trefoil, tall fescue, and kenaf) in
Phytoremediation projects aimed at reducing soil Se
levels to below toxic concentrations are reviewed. The
best plants for these types of projects include Brassica
and. Astragalus species.
Phytoremediation of Uranium-Contaminated Soils:
Role of Organic Acids in Triggering Uranium
Hyperaccumulation in Plants
Huang, J.W.; Blaylock, M.J.; Kapulnik, Y.; and Ensley,
B.D.
Environmental Science & Technology v 32:7 p 2004(5)
1998
Uranium (U) phytoextraction, the use of plants to
extract U from contaminated soils, is an emerging
technology. In this research, the effects of various soil
amendments on U desorption from soil to soil solution
were investigated, physiological characteristics of U
uptake and accumulation in plants were studied, and
techniques to trigger U hyperaccumulation in plants
were developed. Of the organic acids (acetic acid, citric
acid, and malic acid) tested, citric acid was the most
effective in enhancing U desorption and subsequent
accumulation in plants. Shoot U concentrations of
Brassica juncea and Brassica chinensis grown in a U-
contaminated soil (total soil U, 750 mg/kg) increased
from less than 5 mg/kg to more than 5000 mg/kg in
citric acid-treated soils. These results suggest that U
phytoextraction may provide an environmentally
friendly alternative for the cleanup of U-contaminated
soils.
24
-------
Abstracts of Phytoremediation Resources
Inorganic Contaminants
Potential for Phytoextraction of 137CS from a
Contaminated Soil
Lasat, M.M.; Norvell, W.A.; and Kochian, L.V.
Agricultural Research Service, Beltsville, MD February
1998
Cesium-137 (137Cs) is a long-lived by-product of
nuclear fission. Phytoremediation of
radiocesium-contaminated sites is impeded by the
marked capacity of soils to tightly adsorb 137Cs and
limit its availability for plant uptake. Bioavailability
testing of a number of soil extractants from an aged
contaminated soil obtained from Brookhaven National
Laboratory demonstrated that ammonium salts released
a large portion of the radiocesium trapped in the soil.
This same amendment greatly stimulated the
bioaccumulation of 137Cs in plant shoots. Use of the best
performing plant species from a species selection trial
(cabbage), in conjunction with amending the soil with
ammonium nitrate, resulted in dramatic improvements
in the accumulation of 137Cs in plant shoots compared
with the results of many previous published studies (10
to 300-fold improvement). These findings indicate that
the phytoremediation of 137Cs contaminated soils is a
very promising cleanup technology.
Potential Remediation of 137Cs and 90Sr
Contaminated Soil by Accumulation in Alamo
Switchgrass
Entry, J.A. and Watrud, L.S.
Water, Air, and Soil Pollution v 104:3-4 p 339(14) June
1998
Alamo switchgrass was evaluated on its ability to
remove cesium-137 and strontium-90 from
contaminated soil. Results show that the above-ground
biomass of the plants accumulated 36% of the
cesium-137 and 44% of the strontium-90 in the growth
medium. However, the accumulated concentrations in
the plants declined after two harvests. For both
radionuclides, the duration of exposure correlated
curvilinearly with accumulation by the plants. As the
concentration of both radionuclides increased in the
growth medium, total seedling accumulation and
concentration of radioisotopes in plant tissue also
increased curvilinearly. The overall findings revealed
that Alamo switchgrass may be a good candidate
species for remediating radionuclide-contaminated
soils.
Rhizofiltration: the Use of Plants to Remove Heavy
Metals from Aqueous Streams
Dushenkov, V.; Kumar, P. B. A. N.; Motto, H.; and
Raskin, I.
Environmental Science & Technology v 29:5 p 1239(7)
May 1995
Rhizofiltration is the use of plants to remove heavy
metals from aqueous streams. Hydroponically grown
roots of Indian mustard (Brassica juncea) were
investigated for their ability to remove lead, cadmium,
copper, chromium, nickel, and zinc from solution. The
rate of lead removal depended on the initial
concentration in solution and showed a monotonic
decline with time. Since the magnitude of lead removal
was proportional to the root weight, much faster
removal rates were achieved when a larger root mass
was used. Significant removal rates were also seen for
the other metals. Only live roots were able to remove
metals from solution.
The Role of EDTA in Pb Transport and
Accumulation by Indian Mustard
Vassil, A.D.; Kapulnik, Y.; Raskin, I.; and Salt, D.
Plant Physiology v 117 p 447(7) 1998
Indian mustard (Brassica Juncea) plants exposed to
lead (Pb) and EDTA in hydroponic solution were able
to accumulate up to 55 mmol/kg Pb in dry shoot tissue
(l.l%[w/w]). This represents a 75-fold concentration of
Pb in shoot tissue over that in solution. A threshold
concentration of EDTA (0.25 mmol) was found to be
required to stimulate this dramatic accumulation of
both Pb and EDTA in shoots. The majority of Pb in
these plants is transported in coordination with EDTA.
Exposure of Indian mustard to high concentrations of
Pb and EDTA caused reductions in both the
transpiration rate and the shoot water content. The
onset of these symptoms was correlated with the
presence of free protonated EDTA (H-EDTA) in the
hydroponic solution, suggesting that free H-EDTA is
more phytotoxic than Pb-EDTA. These studies clearly
demonstrate that coordination of Pb transport by EDTA
25
-------
Abstracts of Phytoremediation Resources
Inorganic Contaminants
enhances the mobility within plants of this otherwise
insoluble metal ion, allowing plants to accumulate high
concentrations of Pb in shoots. The finding that both H-
EDTA and Pb-EDTA are mobile within plants also has
important implications for the use of metal chelates in
plant nutritional research.
A Search for Lead Hyperaccumulating Plants in the
Laboratory
Ghosh, S.;andRhyne, C.
Agriculture and Plant Science Meeting, Mississippi
State University, 1997
The research objective is to identify plant species
capable of sustained healthy growth in elevated lead
concentrations and to evaluate their effectiveness in
accumulating high levels of lead in various parts of the
plants. A modified hydroponic growing system was
used to suspend plants in aqueous solutions of either
Hoagland's nutrient medium or varying concentrations
of Pb(NO3)2 in the laboratory. Thirty-three different
plant species were tested and grouped into five
categories based on their growth potential and lead
uptake. Two plant species, Ipomoea lacunosa and
Sesbania exaltata, appear to have significant potential
as lead hyperaccumulators. After the desired exposure
period, plants were harvested and separated into leaves,
stems and roots to analyze and locate the accumulation
of lead in different plant parts. Morphological
characteristics (height and dry weight) of the plants
were also observed.
Selenium Accumulation by Brassica Napus Grown in
Se-laden Soil from Different Depths of Kesterson
Reservoir
Banuelos, G.S.; Ajwa, H.A.; Wu, L.; and Zambrzuski,
S.M.
Agricultural Research Service, Beltsville, MD August
1997
Elevated levels of selenium (Se) have been measured in
sediment at Kesterson Reservoir and contributed to the
death and deformities observed in waterfowl
frequenting this site. As part of a remediation strategy
to lower levels of soil Se, canola was planted in
Se-contaminated sediment collected from the Reservoir,
as well as on-site. Canola lowered Se concentrations
more effectively under greenhouse conditions than in
the field. The study clearly shows that extrapolating
results from greenhouse to field conditions should be
done with caution. Using canola to lower Se levels at
Kesterson Reservoir will be a long-term management
strategy under field conditions.
Test Plan for the Phytoremediation Studies of
Lead-Contaminated Soil from the Sunflower Army
Ammunition Plant, Desoto, Kansas. Vol. 1 and Vol. 2
Behel, D.; Kelly, D.; Pier, P.; Rogers, B.; and Sikora,
F.
233 pp (v 1), 291 pp (v 2) October 1996
NTIS Document Number: ADA342667 (vol. 1)
ADA342668 (vol. 2)
This document provides a test plan for studying and
improving techniques for remediating lead-
contaminated soils using phytoremediation. It also
discusses a study to examine the uptake of lead by
plants in contaminated soil.
Toxicity of Zinc and Copper to Brassica Species:
Implications for Phytoremediation
Ebbs, S.D. and Kochian, L.V.
Journal of Environmental Quality v 26:3 p 776(6) 1997
The toxicity of Zn and Cu in three species from the
genus Brassica was examined to determine if these
plants showed sufficient tolerance and metal
accumulation to phytoremediate a site contaminated
with these two heavy metals. Hydroponically grown 12
day-old plants of Brassica juncea, B. rapa, and B.
napus were grown for an additional 14 days in the
presence of either elevated Zn (6.5 mg/L), Cu (0.32
mg/L), or Zn plus Cu to quantify the toxic effects of
these metals on several different growth parameters.
With few exceptions, both root and shoot dry weight for
all three species decreased significantly in the presence
of heavy metals. In terms of heavy metal removal, the
Brassica species were more effective at removing Zn
from the nutrient solution than Cu. The extent of Zn
and Cu removal was reduced when both metals were
present as compared to the single heavy metal
26
-------
Abstracts of Phytoremediation Resources
Internet Resources
treatments. The implications of these results for
phytoremediation are discussed.
Toxic Mercury Reduction and Remediation Using
Transgenic Plants with a Modified Bacterial Gene
Rugh, C.L.; Gragson, G.M.; Meagher, R.B.; and
Merkle, S.A.
University of Georgia, Athens, GA
HortScience v 33:4 p 618(4) July 1998
The objective of this paper is to give a brief overview of
the concepts and progress of microbial- and plant-
assisted pollution remediation research. A summary of
efforts to genetically engineer plants for mercury
reduction and detoxification, as well as considerations
for future research toward this goal, will be presented.
Zinc and Cadmium Accumulation in the
Hyperaccumulator Thlaspi Caerulescens in Response
to Limestone and Compost Applications to a Heavy
Metal Contaminated Site in Palmerton,
Pennsylvania
Li, Y.M.; Chaney, R.L.; Kershner, B.A.; Chen, K.Y.;
Angle, J.S.; and Baker, A.J.
Agricultural Research Service, Beltsville, MD
September 1997
Research is being conducted to develop a new
technology using plants to remove Zn and Cd from
contaminated soils which require remediation. Thlaspi
caerulescens is a perennial herb which accumulates Zn
(>3%) from soils to much higher foliar levels than
economic crops. At the Palmerton, PA site, soil metal
concentrations are very high and the soils are
non-calcareous. It is likely that Thlaspi may suffer Zn
phytotoxicity. Studies were conducted to characterize
the long term effect of limestone and compost
applications on plant biomass and Zn and Cd
accumulation. In addition, the uptake of metals by
hyperaccumulator T. caerulescens was compared to
uptake by a local metal-tolerant species, Merlin red
fescue. In this paper, we report that compost treatment
reduced metal phytotoxicity. We have also determined
that higher soil pH and organic matter were the
important factors attributing to the large shoot biomass
accumulation for Thlaspi.
Publications Containing Multiple Papers
Metal-Contaminated Soils: In Situ Inactivation and
Phytorestoration
Vangronsveld, J. and Cunningham, S. (eds.)
R.G. Landes, Austin, TX
Bioremediation of Inorganics, Vol. 3
Hinchee, R.E.; Means, J.L.; and Burris, D.R. (eds.)
Battelle Press, Columbus, OH 184 pp 1995
Plants That Hyperaccumulate Metals: Their Role in
Phytoremediation, Microbiology, Archaeology,
Mineral Exploration, and Phytomining
Brooks, R. R. (ed.)
CAB International, New York
Internet Resources
Advanced Applied Technology Demonstration
Facility (AATDF)
http://www.ruf.rice.edu/~aatdf
AATDF is a research facility funded by the Department
of Defense, Army Corps of Engineers, Waterways
Experiment Station (WES) through the Energy and
Environmental Systems Institute at Rice University.
One of its long-term projects involves evaluating and
recommending innovative treatment technologies in
support of faster and cheaper remediation.
Air Force Center for Environmental Excellence
(AFCEE)
http://www.afcee.brooks.af.mil
The Air Force Center for Environmental Excellence
provides a complete range of environmental,
architectural, and landscape design, planning and
construction management services and products.
Environmental restoration is one of its several business
lines, and its services include: studies and
investigations, project design, cleanup, long-term
operation/monitoring, program support, and new
restoration technology research. It was formed in 1991.
27
-------
Abstracts of Phytoremediation Resources
Internet Resources
Alternative Treatment Technology Information
Center (ATTIC)
http ://www. epa. gov/attic
The EPA Office of Research and Development (ORD)
Alternative Treatment Technology Information Center
(ATTIC) is a comprehensive computer database system
providing up-to-date information on innovative
treatment technologies. ATTIC provides access to
several independent databases as well as a mechanism
for retrieving full-text documents of key literature. The
system provides information to make effective decisions
on hazardous waste clean-up alternatives.
CLU-IN: Hazardous Waste Clean-Up Information
http://clu-in.org
The Hazardous Waste Clean-Up Information (CLU-IN)
Web Site provides information about innovative
treatment technologies to the hazardous waste
remediation community. It describes programs,
organizations, publications, and other tools for federal
and state personnel, consulting engineers, technology
developers and vendors, remediation contractors,
researchers, community groups, and individual citizens.
The site was developed by the U.S. EPA but is intended
as a forum for all waste remediation stakeholders.
Environmental Security Technology Certification
Program (ESTCP)
http://www.estcp.org
ESTCP's goal is to demonstrate and validate promising,
innovative technologies that et the Department of
Defense's (DoD's) most urgent environmental needs.
These technologies provide a return on investment
through cost savings and improved efficiency. The
current cost of environmental remediation and
regulatory compliance in the Department is significant.
Innovative technology offers the opportunity to reduce
costs and environmental risks. ESTCP's strategy is to
select lab-proven technologies with broad DoD and
market application. These projects are aggressively
moved to the field for rigorous trials that document
their cost, performance, and market potential.
Successful demonstration leads to acceptance of
innovative technologies by DoD end-users and the
regulatory community.
Federal Remediation Technologies Roundtable
http://www.frtr.gov
The mission of the Roundtable is to exchange
information and provide a forum for joint activity
regarding the development and demonstration of
innovative technologies for hazardous waste site
remediation. The exchange synthesizes the technical
knowledge that Federal Agencies have compiled and
provides a more comprehensive record of performance
and cost. Members include major developers and users
of these technologies: Department of Defense (U.S.
Army, U.S. Army Corps of Engineers, U.S. Navy, U.S.
Air Force), U.S. Department of Energy, U.S.
Department of the Interior, and the U.S. Environmental
Protection Agency.
GNET: The Global Network of Environment and
Technology
http ://www. gnet. org
GNETฎ is an on-line global information center for
environmental technology. The site contains an
interactive environmental technology database
(TechKnow) that houses information on
phytoremediation and over 1,500 other technologies.
Great Plains/Rocky Mountain Hazardous Substance
Research Center
http://www.engg.ksu.edu/HSRC
Kansas State University leads a fourteen-institution
consortium for the Great Plains/ Rocky Mountain
Hazardous Substance Research Center. The other
member institutions are Lincoln, Haskell Indian
Nations, Colorado State, Montana State, South Dakota
State, and Utah State Universities, along with the
universities of Iowa, Northern Iowa, Missouri,
Montana, Nebraska, Utah, and Wyoming. The center
was established in 1989 to conduct research pertaining
to hazardous substances produced through agriculture,
forestry, mining, mineral processing, and other
28
-------
Abstracts of Phytoremediation Resources
Internet Resources
activities of local interest. It serves Federal Regions 7
and 8. Specific research projects focus on soil and water
contaminated by heavy metals from mining wastes and
other industrial activities, soil and ground water
contaminated by organic chemicals, wood preservatives
that contaminate ground water, pesticides identified as
hazardous substances, improved technologies and
methods for characterizing and analyzing contaminated
soil, and waste-minimization and pollution-prevention
methods and technologies. The tables of contents,
abstracts, and selected papers of the Proceedings of the
Annual Conference on Hazardous Waste Research
beginning with the Ninth Annual Conference (1994)
onward may also be viewed at the Web site.
Ground Water Remediation Technologies Analysis
Center (GWRTAC)
http://www.gwrtac.org
The Ground Water Remediation Technologies Analysis
Center (GWRTAC) is a focal point for the collection
and analysis of information on ground water
remediation. The members of GWRTAC compile,
analyze, and disseminate information on innovative
ground water remediation technologies. Technical
teams are selectively chosen from Concurrent
Technologies Corporation (CTC), the University of
Pittsburgh, and other supporting institutions.
Innovative Treatment Remediation Demonstration
(ITRD)
http://www.em.doe.gov/itrd
The Innovative Treatment Remediation Demonstration
(ITRD) Program is funded by the DOE Office of
Environmental Restoration (EM-40) to help accelerate
the adoption and implementation of new and innovative
remediation technologies. Developed as a
Public-Private Partnership program with Clean Sites,
Inc., and the Environmental Protection Agency's (EPA)
Technology Innovation Office (TIO) and coordinated
by Sandia National Laboratories, the ITRD Program
attempts to reduce many of the classic barriers to the
use of new technologies by involving government,
industry, and regulatory agencies in the assessment,
implementation, and validation of innovative
technologies.
Interstate Technology and Regulatory Cooperation
Working Group (ITRC)
http://www.sso.org/ecos/itrc
The Interstate Technology and Regulatory Cooperation
Working Group (ITRC) was established in December,
1994 by the Develop On-Site Innovative Technology
Committee, referred to as the DOIT Coordinating
Group of the Western Governors Association. The
Mission of the ITRC is to facilitate cooperation among
states in the common effort to test, demonstrate,
evaluate, verify and deploy innovative environmental
technology, particularly technology related to waste
management, site characterization and site cleanup.
Regulators from 24 states are collaborating with
representatives from federal agencies, industry, and
stakeholder groups to raise the comfort level of
environmental decision makers about using new
technologies. By pooling their experience and
knowledge in permitting innovative technologies and
by publishing and distributing their work products,
ITRC is making it easier for state regulatory agencies to
approve new technologies.
PHYTONET - Phytoremediation Electronic
Newsgroup Network
http ://www. dsa.unipr. it/phytonet
The Phytonet Newsgroup was developed to allow easy
worldwide communications between scientists who
work on problems related with Phytoremediation and
Application of Plant Systems to Environmental
Control. The Phytoremediation Electronic Network,
moderated by Nelson Marmiroli, is operated by the
Department of Environmental Sciences, University of
Parma, Italy.
Remediation Technologies Development Forum
(RTDF)
Phytoremediation of Organics Action Team
http: //www. rtdf. org/public/phyto
29
-------
Abstracts of Phytoremediation Resources
Internet Resources
The Phytoremediation of Organics Action Team was
established in 1997, as one of seven Action Teams
under the Remediation Technologies Development
Forum (RTDF). The Phytoremediation of Organics
Action Team includes representatives from industry
and government who share an interest in further
developing and evaluating the of use of plants and trees
to remediate contaminated soil and water.
Strategic Environmental Research and Development
Program (SERDP)
http://www.serdp.gov
The Strategic Environmental Research and
Development Program is the Department of Defense's
(DoD) corporate environmental R&D program, planned
and executed in full partnership with the Department of
Energy (DOE) and the Environmental Protection
Agency (EPA), with participation by numerous other
federal and non-federal organizations. Within its broad
areas of interest, the Program focuses on Cleanup,
Compliance, Conservation, and Pollution Prevention
technologies.
U.S. Army Corps of Engineers Phytoremediation
Research
http://www.wes.army.mil/EL/phyto
The U.S. Army Corps of Engineers Innovative
Technology Program mission is to inform, encourage,
promote, and support the development and use of
innovative technology for environmental investigation
and remediation. Its Phytoremediation Research site is
part of the Waterways Experiment Station
Environmental Laboratory Web site.
U.S. Army Environmental Center (USAEC)
http ://aec-www. apgea. army. mil: 8080
The USAEC Technology link provides access to
descriptions of innovative restoration technology
demonstrations conducted at numerous Army
installations.
U.S. Department of Agriculture (USDA)
http://www.usda.gov
In addition to supporting research to improve
agricultural production, the USDA also supports
research concerning remediation of soil and ground
water contaminated with pesticides, herbicides, and
fertilizers. The Current Research Information System
(CRIS) database is a documentation and reporting
system for ongoing and recently completed research
projects. The Technology Transfer Automated Retrieval
System (TEKTRAN) provides abstracts of research
results from the UDSA's Agricultural Research Service
that will be published as articles or documents.
CRIS:http://cristel.nal.usda.gov:8080
TEKTRAN: http://www.nal.usda.gov/ttic/tektran
30
------- |