**Yong Cai, FIU assistant professor of Chemistry and faculty member of
the Southeast Environmental Research Center, is leading the team that is
working with scientists at the University of Florida that recently
discovered that the Pteris Vittata (brake fern) is extremely efficient
in extracting arsenic from soils and relocating it to its fronds. Cai
co-authored an article on the discovery in the February issue of Nature.
The possible future use of the brake fern for "phytoremediation" - an
emerging, plant-based technology for the removal of toxic contaminants
from soil and water - has project members energized. Arsenic-tainted
soil is a major cause of arsenic-tainted drinking water and food
worldwide. Concerns over arsenic-tainted soil found at playgrounds
constructed of specially treated wood recently prompted Miami-Dade
County officials to shut down or restrict access to portions of several
county parks and playgrounds.
Cleanup is an even more difficult proposition: Current methods of soil
remediation are expensive, according to Cai, and would be far less
practical than use of the versatile, hardy, fast-growing brake fern.
Although many plants have been identified as those that accumulate
metals extremely quickly and efficiently -- "hyperaccumulators"-- no
hyperaccumulator for arsenic had been previously reported.
MORE AT: http://news.fiu.edu/releases/2001/5-21arsenic_ferns.htm
Betty wrote:
<<. . . I found a lab that sells ferns that will take up the arsenic.
Unfortunately, I don't recall the variety of fern. >>
I have heard before of many plants being used to
extract toxins from soil. I have wondered though -
what happens to the plants once they have absorbed the
toxin? If you composted them, wouldn't they simply
return the toxin to the soil? So does that mean that
they end up in landfill? Is there a way to extract
the toxin?
=====
Merry Luskin, Oakland CA
Reference librarian and handspinner
Weeder, Librarians' Index to the Internet
http://lii.org
MLuskin wrote:
I guess this IS something to be concerned about Merry. As you correctly
say the plants cannot be composted once they have done their job or you
simply put the problem element back in the soil. Adding them to a
landfill is not much better.
Tony says that if the stuff they have extracted is valuable enough to be
worth recovering the plants may be ashed to facilitate this.
Moira
--
Tony & Moira Ryan,
Wainuiomata, North Island, NZ. Pictures of our garden at:-
http://mywebpages.comcast.net/cherie1/Garden/TonyandMoira/index.htm
