Test for arsenic in old paint?
Anthony Hay
dark green mat paint. I don't think it is an oil based paint. It's on
lime plaster. A friend told me arsenic was used to colour paint in years
gone by. The house is late C18.
Does anyone know how I could test for arsenic?
Does anyone know how to get rid of arsenic paint?
(Wasn't it arsenic in the wallpaper that killed Napoleon?)
Worried of Wiltshire
Willy Eckerslyke
>
> While decorating I recently removed some wallpaper and revealed some
> dark green mat paint. I don't think it is an oil based paint. It's on
> lime plaster. A friend told me arsenic was used to colour paint in years
> gone by. The house is late C18.
Dunno about dark green, we found traces of a greeny-turquoise paint
that I took to be arsenic. A recent programme about the restoration
of Aberglasny House showed something very similar looking. They made
a big deal about it.
I just sealed mine in by replastering over it as advised at the time.
> Does anyone know how I could test for arsenic?
I can think of one...
> Does anyone know how to get rid of arsenic paint?
Do you really need to?
> (Wasn't it arsenic in the wallpaper that killed Napoleon?)
Allegedly.
> Worried of Wiltshire
Don't be. It never did me any ha
Tim Clement
<no.spa...@centennial.co.uk> wrote:
>While decorating I recently removed some wallpaper and revealed some
>dark green mat paint. I don't think it is an oil based paint. It's on
>lime plaster. A friend told me arsenic was used to colour paint in years
>gone by. The house is late C18.
>
>Does anyone know how I could test for arsenic?
>
>Does anyone know how to get rid of arsenic paint?
>
>(Wasn't it arsenic in the wallpaper that killed Napoleon?)
>
>Worried of Wiltshire
>
I seem to remember that in one of the Wimsey stories, Lord Peter (or
possibly Bunter) conducts a test for arsenic. I have an even vaguer
recollection that the trick is to produce the hydride, which is
volatile, and then get it to decompose, leaving a characteristic
silvery film.
A real chemist will be along in a minute . . .
Tim
john_h_schmitt
hu...@nospam.demon.co.uk (Huge) wrote:
[arsenic testing]
> Sounds like the Marsh test to me. Something along the
> lines of mixing
> the suspect compound with concentrated sulphuric acid,
> passing the gas
> evolved through a pyrex tube heated in a bunsen flame.
> As you rightly
> say, you get a characteristic silvery film of arsenic
> metal in the
> tube.
The Marsh test is the more commonly used. The suspect
substance is mixed with dilute sulphuric acid and zinc
granules. If Arsenic is present the hydride, arsine (AsH_3)
is produced. As it (and the hydrogen generated) pass
through the heated tube, the arsine decomposes to leave
arsenic as a dark discolouration in the tube. Antimony also
gives a similar result, but the discolouration is soluble
in sodium hypochlorite. There is also Gutzeit's test which
is similar, except for the detection of arsine is done with
filter paper treated with silver nitrate. I assume that the
nitrate is reduced to metallic silver, giving a dark stain
on the filter paper. Both these tests are sensitive to low
ppm levels, and were developed for testing beer, which is
quite another story. However, to get a good test, you will
have to ash some of the paint, and this is not a procedure
you should try at home. Try your local council's
environmental section.
John Schmitt
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Anthony Hay
> Dear Worried of Wiltshire,
>
> I advise you not to lick your wallpaper. It's probably not a good idea to
> lick your hands too much after touching the wallpaper either.
>
> Otherwise, don't be worried!
Thanks for that Adrian.
I can assure you I don't intend to lick the walls. However, I have asked a
decorator to prepare the walls for painting. He said he would sand the old
paint off as the green paint has been deliberately chipped away all over to
reveal light colour wall beneath. The walls are thus green with cream spots.
(I have no idea why this was done.) I told him my worries about arsenic but
he said it would be fine. But obviously I don't want to poison my wife and
children with arsenic dust.
I want to paint the walls with distemper.
Not Reassured of Wilts.
Andy Wade
> I want to paint the walls with distemper.
Can you still get distemper? I though it had been completely superceded by
emulsion paint.
--
Andy
Phil McCavity
and see if they keel over ;o)
Andy Wade
> Paint Magic sell distemper. Naturally.
But is it _real_ distemper (whiting and glue size) - and who are Paint
Magic anyway?
--
Andy
Douglas de Lacey
> if there's a way to make it look more distemper-y than the original
> stuff, she's probably found it. The shops specialize in "effects"
> paints -- crackle glaze, for instance, and that very thin paint that
> you smear on top of another colour of paint with a sponge. There's
> a name for this but I can't remember what it is.
Wash? If you roll the sponge it's Rolling (and if you use a rag instead
it's Rag Rolling:-) I didn't know she had a shop but she's written a
couple of quite good books on special paint effects of this kind. With
their help, and fairly ordinary paints, my teenage daughter transformed
her room with very little help from us, and it still looks great 3 years
on.
Douglas de Lacey.
Andy Wade
> Jocasta Innes.
Ah, thought I'd heard that phrase before. Didn't she write a book of the
same name?
--
Andy
Douglas de Lacey
> but it seems likely.
According to our Library catalogue (http://www.lib.cam.ac.uk/) she's
written over 30! Including:
Author: Innes, Jocasta
Title: Paint magic: the home decorator's guide to painted finishes/
Jocasta Innes
[London]: Windward, c1981 239p; 29cm
though I don't think that is one of the two my daughter used. I believe
the url above is publicly available and will give lots more info.
Douglas de Lacey.
Andy Wade
I was about to say that I thought she's written several - including that
classic 'Doing up a Dump' if I'm not much mistaken.
> I believe
> the url above is publicly available and will give lots more info.
I just tried it. As soon as you try to search the catalogue it asks for a
username and password. Guest & guest didn't work, alas...
--
Andy
Anthony Hay
Thank you John and Huge for the advice. I tried the local council (North Wilts)
environmental health dept. but they won't test any paint themselves. However,
they gave me the name of a co. in Bristol who will. They in turn put me on to
another co. called Waterfall & O'Brien Analytical Chemists (0117 9583448) who,
for £28 + VAT, will test a sample of paint for arsenic. So I've just sent some
off to them.
Waiting of Wilts.
Anthony Hay
Andy Wade wrote:
> Can you still get distemper? I though it had been completely superceded by
> emulsion paint.
I intend to get distemper from Rose of Jericho (01935 83676).
The house is old and the walls have no damp-proof course. They arn't too damp
and I don't want to screw them up by painting them with something that won't
allow them to "breath."
Ant
Andy Wade
> I just tried it. As soon as you try to search the catalogue it asks for
a
> username and password. Guest & guest didn't work, alas...
Having just dabbled further I find that the Telnet version does work
without a login. Useful.
--
Andy
Paul C. Dickie
<nospa...@mam.nospam> writes
>Anthony Hay wrote:
>> Does anyone know how I could test for arsenic?
>
Yes, but how *does* one get one's mother-in-law to lick the paint?
--
< Paul >
Paul C. Dickie
va...@tictac.demon.co.uk> writes
>paints -- crackle glaze, for instance, and that very thin paint that
>you smear on top of another colour of paint with a sponge. There's
>a name for this but I can't remember what it is.
Scum-bag glaze?
--
< Paul >
Anthony Hay
Anthony Hay wrote:
In case anyone is interested: The results of the test show that the paint contained
24 parts arsenic per million parts paint, not a significant amount apparently.
Ant.
John Schmitt
Anthony Hay <no.spa...@centennial.co.uk> writes:
>In case anyone is interested: The results of the test show that the paint contained
>24 parts arsenic per million parts paint, not a significant amount apparently.
My back-of-an-envelope calculation would suggest you would need to ingest
several kilograms of that paint to suffer ill-effects, so I would classify it
as safe.
John Schmitt
"Visitors are requested to keep to the paths and are strictly prohibited from
touching monumental erections, trees, flowers and plants."
Allegedly a sign in a New Jersey cemetery.
The usual disclaimers apply, naturally.
inclusus...@gmail.com
> While decorating I recently removed some wallpaper and revealed some
> dark green mat paint. I don't think it is an oil based paint. It's on
> lime plaster. A friend told me arsenic was used to colour paint in years
> gone by. The house is late C18.
>
>
>
> (Wasn't it arsenic in the wallpaper that killed Napoleon?)
>
> Worried of Wiltshire
Green paint from the 18th and 19th circa is likley to contain arsenical pigments such as copper arsenate and/or lead arsenate.
They are both highly toxic.
Because of this, I strongly advise you NOT to attempt to remove the paint as this would greatly increase your exposure risk not to mention how will you dispose of - legally - the old paint.
My advice is to over paint with several coats of good quality paint. You can also paper it over before painting. If the paint is present in damp areas subject to mould growth use an anti-mould paint undercoat. Its mouild that turns arsenical paints into potential killers. If you or your family are worried about arsenic exposure, your GP can arrange a blood or urine test for heavy metals.
You have done the right thing by sending a sample to an approved laboratory.
Try not to worry too much, the best course of action is not to disturb the old paint and cover it with fresh paint and/or paper the offending paint before painting.
I am a registered chemist specialising in toxicology so feel free to ask anytime you are concerned.
Best wishes
Simon
Scott M
> On Monday, September 27, 1999 at 8:00:00 AM UTC+1, Anthony Hay wrote:
> I am a registered chemist specialising in toxicology
--
Scott
Where are we going and why am I in this handbasket?
GB
> inclusus...@gmail.com wrote:
>
>> On Monday, September 27, 1999 at 8:00:00 AM UTC+1, Anthony Hay wrote:
>
>> I am a registered chemist specialising in toxicology
>
> But not very observant about dates.
>
Martin Bonner
Graham.
wrote:
substitute for a news server and news reader client.
When Google acquired it in 2001 they set about merging it into their
own "Google Groups" and tried blur the line as to what is Usenet and
what wasn't. I doubt if Scott has even heard of Usenet
--
Graham.
%Profound_observation%
Graham.
via GG, he's using aioe.org.
So how's that happened?
--
Graham.
%Profound_observation%
Graham.
Also the actual OP Anthony Hay had a sample analized and it came back
as 24 parts arsenic per million parts paint.
https://groups.google.com/d/msg/uk.d-i-y/WpAPEeYxX1E/LcXOKHEu1UIJ
--
Graham.
%Profound_observation%
Martin Bonner
> Apologies Scott, it's Simon who trawled up the old post not you!
>
> Also the actual OP Anthony Hay had a sample analized and it came back
> as 24 parts arsenic per million parts paint.
>
> https://groups.google.com/d/msg/uk.d-i-y/WpAPEeYxX1E/LcXOKHEu1UIJ
being worried about arsenic in soil: 32 mg/kg
https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/313869/scho0409bpvy-e-e.pdf
I think I'd still prefer to wet strip it though.
Rod Speed
>>> I am a registered chemist specialising in toxicology
>> But not very observant about dates.
> Does Google Groups just dredge up these old posts without any warnings?
newshound
some old green matt paint on a wall, also 18th century although I
suspect that this might be Victorian. I wondered about arsenic too,
since it's not quite the classic colour of verdigris or typical
corrosion of copper. I have a sample waiting to sneak into an SEM with
EDAX next time I have an opportunity.
But I also did some research on the net, and found that it's just the
shade of Malachite, another green pigment with long ancestry. This is
basic copper carbonate, so still a bit toxic but *not* as bad as arsenic.
Some of it came off easily dry with a stripping knife, but some is very
adherent. I deliberately didn't sand it, I tried to avoid inhaling dust
and vaccumed fairly carefully before sealing with PVA, and I am going to
put heavy duty lining paper over it.
Scott M
> Apologies Scott, it's Simon who trawled up the old post not you!
over 20 years ago (god I feel old!)
Martin Brown
latch onto particular keywords.
--
Regards,
Martin Brown