lead-contamination.in.soil

To: london@sunsite.unc.edu
Subject: lead-contamination.in.soil
From: Larry London <london@calypso>
Date: Wed, 26 Jan 1994 16:40:30 -0500
Article 22027 of rec.gardens:
Newsgroups: rec.gardens
Subject: Lead from Paint
From: jim.mcnelly@gcbb.granite.mn.org (Jim Mcnelly)
Path: samba.oit.unc.edu!concert!news-feed-1.peachnet.edu!umn.edu!uum1!gcbbgw!gcbb!jim.mcnelly
Distribution: world
Message-ID: <36.470.2552.0N41B8F9@gcbb.granite.mn.org>
Date: Tue, 31 Aug 93 00:00:00 +0600
Organization: Granite City BBS 612-654-8372 hst 656-0678 v.32bis
Lines: 72

Ebf@Cbnewst.Cb.Att.Com to All - Sunday, August 29th:

on August 29, 19 92 Discussing: Lead from Paint

E>Message-ID: <CCHH1u.9tz@cbnewst.cb.att.com>
 >Newsgroup: rec.gardens
 >Organization: AT&T

E>My VERY old house was power washed 2 years ago,
 >and lead paint made its way into the soil

E>Tomatoes are growing within 6 feet of the house --
 >is it possible for the plants to take up the lead
 >from the soil and  deposit the lead in the tomato fruits?

E>Is there a way to cheaply test for lead concentration
 >in the soil or in the tomatoes themselves?

There is no inexpensive test for lead concentration in soil that I know
of. Water is a different matter, but soil no. The cost is in the setting
up and preparation of the sample. Once set up, it is easy to test for
additional heavy metals such as mercury, cadmium, chromium, etc. I would
expect the test to run upwards of $200.

There are two levels of lead of concern, Parts Per Million (PPM) and
extractable, or leachable lead. The EPA hazardous level for lead is 5000
PPM, the leachable level is 5. There is virtually no chance that your
lead is in a leachable form since it is from paint, so there is no point
even running the leach test.

Background lead levels will run from 50 PPM up to 250 PPM. Soils near
traffic areas will typically be high around 500 PPM from lead from
gasoline. Even with the lead removed, it is still in the soil from years
ago. Lead does not typically migrate and it certainly does not decay
into something else. Once it is there, it is always there.

Lead limits in sludges and compost are set at either 500 PPM or 1000 PPM
before the sludge must be landfilled rather than used beneficially. Even
more of concern is the total pounds of lead added to the soil per acre,
since compost and sludge are diluted with the topsoil, but accumulate
over years.

There is little to do with lead contaminated soil other than to remove
it and bury it somewhere where it will not erode or grow crops, such as
a landfill. From paint sources, the lead will typically be in the
surface few inches as it is a large element and does not migrate
through the soil quickly. If you scraped off the old soil a few inches
deep, where the paint was or accumulated, you will have removed most of
it. Send it to a conventional sanitary landfill, possibly a demolition
fill. Do not spade or till it into the soil, as that only makes for more
topsoil that must be removed.

Lead does not readily accumulate in plants. Its problem comes in root
vegetables where it is adhered to the root as a part of the topsoil. The
more serious problem is children eating lead paint chips or the soil
itself, a phenomenon known as the "pica" syndrome. Lead can also be
breathed as a dust, and surprisingly, the skin absorbs lead quickly.
Much has been made of lead in drinking water. So the pathway to the body
is direct, rather than secondary through plants.

I hope this information helps.

Mr Compost~~~


Jim~~~

Granite Cities BBS 612-654-8372-HST 654-0678 v.32bis

e-mail jim.mcnelly@granite.mn.org
---
 * August 30th - Sure, when... OINK FLAP OINK FLAP... Well I'll be damned!