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Re: question
There's another source:
Hg from chlorine production or use as a catalyst in VCM processes
such as the one used by Borden in Geismar, LA, which shipped mercuric
chloride to South Africa's Thor facility, which has contaminated the
area (so badly that even the US Justice Dept is involved in a
yet-to-be resolved case). PPG in Lake Charles also uses tremendous
amounts of mercury, which has shown up inlocal fish in the Calcasieu
Estuary.
Also, in ATSDR's report under "USE" of mercury, they say this:
Page 299: "The largest commercial use of mercury in the United States was
for electrolytic production of chlorine and caustic soda in mercury cells,
accounting for 35% of domestic consumption. (USGS 1997)."
Page 300: Chemical/mining applications: "Mercury is a catalyst in
reactions to form polymers, such as vinyl chloride and urethane foams. The
preparation of chlorine and caustic soda (NaOH) from brines also uses
mercury as a catalyst. In this process, mercury is used as a moving
cathode to separate sodium and chlorine."
Page 300: Other applications: "Phenylmercuric acetate has been used in
aqueous systems such as inks, adhesives, and caulking compounds, as a
catalyst for the manufacture of certain polyurethanes, and as a fungicide
in seed dressings and interior and exterior paints.)"
Page 300: Discontinued applications: "The use of phenylmercuric acetate
as a fungicide in interior latex paints was banned in 1990 and in exterior
paint was banned in 1991. Both of these bans were prompted because of
releases of mercury vapors as the paint degraded. Alkyl mercurial
compounds were used until the mid-1970s as a treatment to disinfect grain
seeds. Most other agricultural applications of mercury compounds in
bactericides and fungicides have been banned due to the toxicity of
mercury. Mercuric nitrate was used in the production of felt hats to
hydrolyze rabbit fur. The use of mercury as a wood preservative has ceased
due to the use of polyurethane."
They cite the following companies (some which we note
make VCM for PVC). "Facilities that Manufacture or Process Mercury":
(Table 4-1,Page 297)*
Range of maximum amounts on site in pounds
Occidental Petroleum Corp. Muscle Shoals, AL 100,000-999,999
Occidental Petroleum Corp Delaware City, DE 100,000-999,000
Occidental Petroleum Corp. Deer Park, TX 1,000,000-9,999,999
(VCM)
BF GOODRICH Calvert City, KY 100,000-999,000 (VCM)
PPG Ind. Inc. Lake Charles, LA 100,000-999,999 (VCM)
Dow Chemical Co. Plaquemine, LA 1,000-9,999 (VCM?)
(Borden) Geismar, LA 10,000-99,999 VCM
(The "activities and uses" of the above are "As a chemical processing aid."
Except for Dow, "As a reactant; As a manufacturing aid." And for (
Borden) "Import; For on-site use/processing; As a chemical processing
aid.")
*"These data should be used with caution, however, since only certain types
of facilities are required to report. Therefore, this is not an exhaustive
list." (Page 296)
Perhaps Dr. Bill will explain what Oxy uses so much mercury for?
Date: Fri, 19 Dec 1997 12:58:16 -0500 (EST)
Reply-to: scmcclintock@ipass.net
From: Sam McClintock <scmcclintock@ipass.net>
To: Multiple recipients of list <dioxin-l@essential.org>
Subject: Re: question
cc: Susan
Susan Snow wrote:
> Can anyone answer the following question for a friend of mine?
>
> Is there any possibility that mercury could be produced as a by-product
> of the PVC plastic production process, including incineration?
>
> Susan Snow
Short answer: Normally no, but it is slightly possible to have a problem.
You cannot produce mercury (Hg) in the sense that most people think of,
e.g. you have several compounds in a tank that are NOT Hg and Hg is formed
by their reaction. Hg is not formed by simple chemical reactions.
However, Hg can work its way into any manufacturing process as a trace
contaminant, e.g. something that was not intentionally made or placed their
but because it was impossible to remove all traces of Hg from the process.
You can find Hg as a trace contaminant in many things, more commonly
pigmentation that may go into PVC production (though not a lot). It might
help in understanding the process in that one of the white pigments, one of
the more common colors, comes from the processes of refining titanium ore,
rutile, just stuff you dig out of the ground. Have no idea if it is the
same pigment used in plastic production, but it is easy to see how very
small amounts of Hg can get caught up with everything to make a pigment of
any type.
A (sadly) more important source of trace contamination is our own
environment. Because we have used mercury for so many things, it can be
found almost anywhere in the environment. The term "mad as a hatter" come
from workers suffering nervous disorders because Hg was used in felt
production of hats, and most people know/remember of the Minamata (sp?)
disaster of 52 (Japan). So it can get picked up in a lot of things.
What does this mean for PVC production and incineration. 1) Incineration
of anything will generally emit trace contaminants of metals, though with
plastics those numbers are NORMALLY going to be quite low (not a
significant health risk). 2) The PVC facility may have elevated emission
levels of mercury because a) someone is burning something in the scrap
incinerator they are not supposed to, b) an additive or compound is coming
from a source with extremely high trace contamination (see previous
discussions of lead), or c) some new process or catalyst is having Hg
leached from production/surface. (a) and (b) above would be rare cases,
(c) I suspect would be very rare. But it COULD happen, just like any other
"simple" mistake when it comes to manufacturing anything in our society.
On the plus side, if Hg were found in air or water discharge from any
facility in detectable amounts, it should be relatively easy to figure out
where it was coming from.
Normally, you would not look for Hg discharges from a PVC facility.
Sam McClintock
mac@ensanity.com
Charlie Cray
Greenpeace US Toxics Campaign
847 W. Jackson Blvd., 7th floor
Chicago, IL 60607
Ph: (312) 563-6063
Fax: (312) 563-6099
Note new e-mail address: Charlie.Cray@dialb.greenpeace.org