PHYTOREMEDIATION OF PERCHLORATE AND N-NITROSODIMETHYLAMINE AS SINGLE AND CO-CONTAMINANTS
Impact/Purpose:
Specific objectives of the project are to: 1) determine
the fate of perchlorate taken up into plants and after senescence; 2) evaluate
the feasibility
of using plants to degrade NDMA; 3) identify the transformation pathways and
mechanisms of phytoremediation of NDMA; 4) establish whether woody plants selectively
take up perchlorate or NDMA when they occur as co-contaminants; and 5) determine
the role of nitrate during phytoremediation of NDMA.
Description:
Although potential plant species suitable for phytoremediation
of perchlorate and the phytoprocesses involved (rhizodegradation and phytodegradation)
have been identified in previous research, regulators and some critics argue
that plants recycle the perchlorate fraction taken up into the plant. There
is no published work to date on phytoremediation of N-nitrosodimethylamine
(NDMA). The proposed studies will include laboratory, greenhouse and field
components. Test plants for the phytoremediation of perchlorate and NDMA will
be willow (Salix nigra) and eastern cottonwood (Populus deltoides).
Record Details:
Record Type:PROJECT(
ABSTRACT
)
Start Date:10/01/2003
Completion Date:09/30/2005
Record ID:
75741
Keywords:
BIOSTIMULATION, COTTONWOOD, PHYTODEGRADATION, PHYTOACCUMULATION, BIOREACTORS, RHIZODEGRADATION, RADIOLABELED, WILLOWS.,
Related Organizations:
Role
:OWNER
Organization Name
:FLORIDA AGRICULTURAL AND MECHANICAL UNIVERSITY
Citation
:Tallahassee
State
:FL
Zip Code
:32307
Project Information:
Approach
:Willow (Salix nigra) and eastern cottonwood (Populus deltoides)
will be used in this study. Experiments on uptake and transformation rates
of NDMA will be conducted in hydroponic reactors. The uptake and transformation
rate will be measured by extracting 5 mL of solution for analysis once every
24 hours. The withdrawn samples will be filtered with a 0.45 micron filter
before analysis by HPLC, GC/MS and LC/MS/MS. Sand and soil bioreactor experiments
will be conducted in 5 gallon buckets filled with either acid washed silica
play sand or soil from a perchlorate and NDMA contaminated site. Each sand
bioreactor will contain the same mass of sand, volume of water, concentration
of nutrient, and dosed to the same initial NDMA concentration as in the contaminated
soil. Test plants of approximately the same biomass will be transplanted in
each bioreactor. The level of water in each bioreactor will be kept constant
by replenishing evapotranspired water multiple times daily. Different types
of controls will be prepared and handled in parallel to quantify losses due
to sorption and biodegradation. The bioreactors will be maintained at ambient
temperature under natural light in a greenhouse. Similar experiments will be
conducted using radiolabeled perchlorate and NDMA as co-contaminants. Phyto-transformation
products and mass balance of NDMA using willow and cottonwood will be determined
in specially designed experiments to obtain quantitative data on the distribution
of metabolites and the parent compound between the solution phase and the plant
matter. Liquid scintillation procedures will be used to quantify the amount
of polar fraction of metabolites in comparison to the total 14C-NDMA activity.
A biological tissue oxidizer will be used to quantify the irreversibly bound
fraction. GC/MS and LC/MS/MS analytical techniques will be used to identify
metaboli
Cost
:$399,875.00
Research Component
:Hazardous Waste/Remediation
Project IDs:
ID Code
:R831090
Project type
:EPA Grant