Phil Nelson wrote:
PCBs are one of the most dangerous substances ever created. Oil-filled
capacitors containing PCB were made as early as the 1930s. The AR88 was a
wartime set, more likely than consumer radios to contain oil-filled
capacitors.

There is no "safe level" of exposure to PCBs, and they do not break down in
the environment. I would not risk cleaning out the old cans and putting new
capacitors into them. Why not contact your local hazardous waste agency and
find out how you can safely (and legally) dispose of the capacitors?

This web article -- I'm sure you can find many others -- gives some history
about PCBs and their health effects.

http://www.foxriverwatch.com/monsanto2a_pcb_pcbs.html

It's a very interesting paper, it appears to have been written mostly
to scare, and to hopefully encourage one to become an environmental activist.

However, every single point you mention above about the dangers is counter to
what is actually said in the article: it does biodegrade, it takes fairly
large exposure to cause chloroacne, or liver problems...

Did you actually read the article?

-Chuck

Chuck Harris wrote:
It's a very interesting paper, it appears to have been written mostly
to scare, and to hopefully encourage one to become an environmental activist.

However, every single point you mention above about the dangers is counter to
what is actually said in the article: it does biodegrade, it takes fairly
large exposure to cause chloroacne, or liver problems...

Did you actually read the article?

I am told that the real problem with PCBs is that they degrade into some
very hazardous things when burned. Although, of course, they don't burn
easily, which was the whole point of using them.

I used to wade knee-deep into tanks of the stuff, and slather it all over
transformer windings with bare hands. It turns out this is probably a bad
thing, but I haven't noticed any problems yet.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

I used to wade knee-deep into tanks of the stuff, and slather it all over
transformer windings with bare hands. It turns out this is probably a bad
thing, but I haven't noticed any problems yet.

I smoked cigarettes for over 20 years, then quit. It turns out this is
probably a bad thing, but I haven't noticed any problems yet . . . .

Best wishes,

Phil "famous last words" Nelson

Phil Nelson wrote:
I used to wade knee-deep into tanks of the stuff, and slather it all over
transformer windings with bare hands. It turns out this is probably a bad
thing, but I haven't noticed any problems yet.

I smoked cigarettes for over 20 years, then quit. It turns out this is
probably a bad thing, but I haven't noticed any problems yet . . . .

Yes, probably a good comparison, I think.

And I remember Lucky Strikes as being advertised as a health product, too,
just as PCB oil was advertised as a safety product. "Reach for a Lucky
instead of dessert" or something like that.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

(Scott Dorsey) writes:

I used to wade knee-deep into tanks of the stuff, and slather it all over
transformer windings with bare hands. It turns out this is probably a bad
thing, but I haven't noticed any problems yet.
--scott

That's okay, Scott -- We have

73s

-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
Lawrence Statton - m s/aba/c/g
Computer software consists of only two components: ones and
zeros, in roughly equal proportions. All that is required is to
sort them into the correct order.

I tackled PCB, Dioxin and Furan toxicity in some depth a while back
(bear in mind there are orders of magnitude difference of alleged
toxicity between these closely related and often co-present
compounds/contaminants, and again in the different sub-types of the
compounds, the levels of which can only be assessed with specialist
testing) and what I found was that industry will tell you they are
low-grade toxicity and cite a ton of scientific study and
environmentalists will tell you they are the ultimate toxin and cite an
equal amount of scientific study.

I certainly wouldn't disregard material just because its blatantly out
to scaremonger. What about all the anti-tobacco ads telling you smoking
gives you cancer - are they spinning BS just because they're out to
scare you?

Acute poisoning (enough to cause chloracne for example) means taking on
a *gargantuan* dose of these types of compounds compared with what is
reckoned to be a 'tolerable daily intake' (TDI), and the levels that
cause concern to professional health bodies like the World Health
Organisation are vanishingly small (single figure picograms) and it is
carcinogenic, teratogenic (birth defects) and immune disorders far down
the line (even in future generations who inherit damaged genes) that
they are worried about, not acute exposure toxicity.

Its difficult getting a decent professional opinion by looking at
industry or environmentalist sourced material, as in my experience they
are equally biased, but I think it is reasonable to accept the view of
a body like the W.H.O, that class Dioxin like PCB's as potentially very
dangerous substances (and known carcinogens) and impose such strict
limits on human exposure.

My area of experience was with dealing with teensy-weensy amounts of
this stuff. The difference in amounts from a waste incinerator (and
diffused) per year and what is *potentially* contained in a few
capacitors is like comparing a hand-grenade to a small nuke in terms of
concentration and yield. They could contain millions of maximum
permissible lifetime doses.

PCB's and the like do biodegrade but can take years to do so, all the
while hanging around in your fatty tissues, doing whatever it is they
are doing (or not doing, depending on your affiliations).

Even taking the middle ground between the industry view and
environmentalist view, the *possible* risks would put me off touching
the stuff or taking any risks with it at all, but thats my personal
opinion.

If it's such harmless stuff, why has it been banned in the US since 1977?
http://www.epa.gov/opptintr/pcb/

To return to his original point -- why would you want to take a risk, if you
can easily and cheaply avoid it?

If you're concerned about authentic appearance, there were postwar metal
bathtub style capacitors which are actually paper caps, not oil filled. I
found some in my Scott Labs 800B, for instance. Get a junker 800B chassis
and scavenge the bathtub cases to restuff, if they look right and that suits
you. You can also buy new or NOS style bathtub caps in a variety of values
and case styles.

Alternatively, you can puncture the old case and drink what's inside, for
all I care. It's a free country :-)

Go in peace,

Phil Nelson

Well, something of a hornet's nest here - pleased you are all enjoying the
debate.

My 'conclusion' thus far:

1) No one actually knows if the capacitors in question contain PCB's
2) If they do, they may or may not be hazardous even in small amounts

3) Therefo

i) I will test the fluid as described in posts
ii) I will treat them as hazardous material in the meantime


Now where did I put my rubber suit?

Bri





"Phil Nelson" wrote in message
...
If it's such harmless stuff, why has it been banned in the US since 1977?
http://www.epa.gov/opptintr/pcb/

To return to his original point -- why would you want to take a risk, if
you can easily and cheaply avoid it?

If you're concerned about authentic appearance, there were postwar metal
bathtub style capacitors which are actually paper caps, not oil filled. I
found some in my Scott Labs 800B, for instance. Get a junker 800B chassis
and scavenge the bathtub cases to restuff, if they look right and that
suits you. You can also buy new or NOS style bathtub caps in a variety of
values and case styles.

Alternatively, you can puncture the old case and drink what's inside, for
all I care. It's a free country :-)

Go in peace,

Phil Nelson

Bri wrote:
Well, something of a hornet's nest here - pleased you are all enjoying the
debate.

My 'conclusion' thus far:

1) No one actually knows if the capacitors in question contain PCB's
2) If they do, they may or may not be hazardous even in small amounts

3) Therefo

i) I will test the fluid as described in posts
ii) I will treat them as hazardous material in the meantime


Now where did I put my rubber suit?

Bri

Bri,

The one part of the discussion that you should note, is that in industry,
folks were literally bathing in the stuff, (occasionally) with no problem.
We have several of those folks here on the group, and they have related their
personal experience.

Every single person that handled carbon and mimeograph paper in the 1930's
through 1970 came into contact with more PCB on each sheet than you will find
in the leakage around your capacitors. PCB was used to keep the ink soft.
Same with stamp pads, TTY ribbons, and single use carbon ribbons. I can vividly
remember the smell of the stuff on those products. Did we have a rash (sic humour)
of secretarial folks with chloroacne, and liver disease?

Other factory folks were exposed to it daily, ate lunch with hands that had it on
them, smoked cigarettes from fingers covered with it, and drank from wells that
were contaminated with the stuff, surprise! some of them showed
some symptoms, such as chloroacne and liver difficulties.

Still other folks got exposed unintentionally, through food made in mills that
accidentally leaked the stuff into the food, and wells that were contaminated by
extreme factory dumping, or ate fish from rivers that were subject to millions
of gallons of factory dumping, and they too showed symptoms.

If you take reasonable precautions to keep the stuff off of your skin, and
out of your mouth, you will not be harmed. Even if you don't, at those small
amounts, it is very doubtful that you will ever show any symptoms.

Now as to disposal: The last time I brought that subject up with the hazardous
chemical group at our local landfill, they were quoting something like $100 for
a single motor run capacitor (that may, or may not have contained PCB).

Better to sell your old caps to the audio/guitar guys on ebay ;-)

-Chuck

Chuck Harris wrote:


The one part of the discussion that you should note, is that in industry,
folks were literally bathing in the stuff, (occasionally) with no problem.
We have several of those folks here on the group, and they have related
their
personal experience.


Thats a bit like the "My grandad smoked 80 a day all his life and lived
to a 101" chestnut. Is this proof that smoking doesn't give you cancer
or that the cancer statistics are wrong?

Personal experience or anecdotal evidence means very little when dealing
with long term toxicity (unless the illness is specifically associated
with a given exposure, like asbestos and mesothilioma). It is medical
statistics of a large, controled group that shed any truth to a matter
such as this. Unfortunately, these are hard to come by because of the
long term nature of PCB toxicity in a society literally bathed in
chemical contaminants and highly mobile.

Even closely monitored exposures, like the Seveso incident in Italy are
inconclusive (I once spoke to the head of toxicology for the UKs
Chemical Response Unit who reckoned that no-one found any ill effect
from that incident, but she was defending a hazardous waste site at the
time.)


If you take reasonable precautions to keep the stuff off of your
skin, and
out of your mouth, you will not be harmed. Even if you don't, at those
small
amounts, it is very doubtful that you will ever show any symptoms.


'Symptoms' are a sign of acute poisoning, obviously to be avoided, but
the health authorities of EVERY developed country would consider someone
with levels of PCBs in thier bodies millions of times less than that
needed to cause 'symptoms' as being over the limit of reccomended
exposure and at possible risk.

Having been exposed to whopping doses doesn't mean you will be
comparitively more ill than someone with a lot less inside them in the
long term - the mechanisims of toxicity of PCBs are not the same as
mercury or arsenic, where the more you have, the sicker you are. The
endocrine system of the body works with tiny amounts of hormones and
messenger chemicals, and its having these messed with that is the real
worry (especially in developing children), and we DO know that PCB's and
the like do just this.

For instance, there is a disorder of the womb that is rampant today
(can't remember the name right now) that was extremely rare before the
invention of PCB's. There can never be a 'smoking gun' leading to the
prescence of all pervasive PCB's in the environment as being the cause
of this (for a number of reasons), but it is EXACTLY the type of illness
predicted to be caused by long term PCB body burden and endocrine
disruption.

The World Health Organisation place a TDI of 1-4 picograms (a picogram
being a *trillionth* of a gram) on Dioxin-like PCB's. That is an
incredibly small amount Chuck, and when dealing with large amounts of
this stuff (meaning any visible amount) you could easily get
comparitively huge doses inside you without noticing, and you can't in
all honesty state with confidence that 'you will not be harmed' by these
amounts. Nobody knows for sure, but there is certainly enough evidence
and (non-hysterical) concern around to be more than cautious.

Andy

Get your free morse ringtone at http://www.planetofnoise.com