Re: [gardeners] toxic marsh

Annetta Green (
Fri, 29 Jun 2001 20:46:39 -0400

Just curious: which Florida wetlands reclamation project are you discussing?

we are discussing the new marshlands being reclaimed at Lake Apopka.  There
was a large bird kill that has been blamed on toxic chemicals spilled on the
land between its time being a marsh.  It was farmland since the 20's and is
being reflooded in small increments since the first time didn't work.
Anne in FL
zone 9b, sunset 26
----- Original Message -----
From: "Dan Dixon" <>
To: <>
Sent: Friday, June 29, 2001 10:33 AM
Subject: Re: [gardeners] toxic marsh

> > From: "Annetta Green" <>
> >
> > what is the half life of DDT?  How long can it sit in the ground and be
> > viable poison?  The research, by state scientists, is showing that the
> > levels of the farm chemicals, most outlawed now, are what is/has been
> > killing the birds.  They found very high levels in the soil, water and
> > birds.  They have been trucking out the worst of the soil and are now
> > to let it flood again.  I think they are also hoping that the second
> > flooding will dissipate even more of the chemicals to acceptable levels
> > the water.
> The problem with DDT is that it is a "POP" chemical: it is subject to
> "Persistently Overstated Paranoia." :)
> Here is Extoxnet's DDT profile:
> Half life varies depending on where it is located, between 2-15 years.
> Breakdown chemicals (DDE and DDD) also persistent, however, so overall
> persistence can potentially be very long. My enviro-geologist friend tells
> me that the deeper DDT gets in the ground, the longer it lasts (don't know
> about 50 yrs, though). DDT is relatively immobile in soil, though, so only
> small amounts get carried down really deep. It was banned in the early
> so it's pushing 30 years since it was last used in the US. Not much DDT
> in the environment in this country, I'd guess.
> Toxicity to birds is slight to almost none. DDT isnt what's killing the
> birds in FL marsh reclamation, at least not directly. They would pretty
> have to eat it raw out of the package to die from it. Contrary to popular
> belief, the eggshell thinning research is not conclusive either, eg, many
> the raptor populations thought to be affected were in trouble before DDT
> used, no direct mechanism linked to DDT is known, etc.
> Just curious: which Florida wetlands reclamation project are you
> Dan Dixon