6/5/97
>To: richard.lander
>From: Richard Easingwood
<richard.easingwood@stonebow.otago.ac.nz>
>Subject: Glutaraldehyde: safe limits
I originally posted this message to a safety listserver where
there is a
discussion running regarding safe limits for glutaraldehyde and
glutaraldehyde monitoring (so it starts in mid 'discussion').
Somebody
suggested I post this on this list as well, I think it is
probably
appropriate to anyone using GA, and I would certainly be
interested to hear
any feedback. From a personal point of view I'd be particularly
interested
to hear from anyone who thinks they've become sensitised to GA
and what
steps they take to minimise exposure.
>
>I too am very skeptical about the maximum 'safe' exposure limit
of 0.2ppm,
>I am also doubtful of the use of the Glutaraldemeter (mentioned
in one of
>the previous replies in this discussion) for measuring safe
limits as a
>result. I should mention at this point that I have developed a
sensitivity
>to glutaraldehyde (GA), probably as a result of a small number
of slight
>exposures to this chemical over the last 6 years in my field of
electron
>microscopy. I know that if I exposed myself to air contaminated
to 0.2ppm
>(as measured by the Glutaraldemeter) it would be dramatically
>debilitating for me - the 'steel band' goes around my chest, my
energy
>levels drop to nothing and I get depressed (common symptoms for
this
>ailment) The depression is so acute it is obviously something
chemically
>induced, as easy to pin point the cause as are jitters after too
much
>coffee. Takes about 12 hours before I feel normal again.
> Now, I realise that most people suffer no such symptoms upon
exposure but
>neither did I for the first 5 years and I was very careful.
Glutaraldehyde
>was known to be hazardous when I first started using it in 1990
and this
>was emphasized to me. In all the time I've used it I've actually
only
>smelt it a handful of times. Now I can only use our preparation
lab when a
>suitable mask, if I get a whiff of GA its too late for me.
>
>Yesterday we measured (using a Glutaraldemeter) the GA
concentrations in
>the air during various laboratory procedures (some very sloppy
on purpose)
>and the levels at no stage went higher than 0.15ppm. The smell
of GA was
>very strong during some of these as judged by two other
volunteers (not
>me, I wore my mask). Our OSH guidelines state that the odour
threshold for
>GA is about 0.04ppm which does not tally with our measurements
made with
>the meter, the smell was gauged as 'very strong' when the meter
read below
>this level. The meter was recalibrated before the tests and
checked again
>immediately afterwards. I can send a report to anyone
interested.
>I should say I have no desire to run down the Glutaraldemeter.
We were
>using it close to its limit of sensitivity afterall. I think
badges fall
>into the same category - they are probably fine if you want to
ensure you
>don't go over the official limit, the problem is that I think
the limit is
>too high.
>
>In conclusion I would say that the official safe maximum peak
exposure
>level of 0.2ppm is too high if you want to avoid the risk of
becoming
>sensitised to GA (and all the inconvenience that brings). I
would say that
>if you can smell it, the level of GA in the air is too high. I
know that
>this probably sounds hopelessly impractical for those working in
Hospitals
>where GA is in widespread use but I believe that we are only
starting to
>appreciate how dangerous GA is.
>
>Regards,
>Richard
>
>
Richard Easingwood
South Campus Electron Microscope Unit
School of Medical Sciences
University of Otago
PO Box 913
Dunedin
NEW ZEALAND
Telephone: 64-03-479 7301
Facsimile: 64-03-479 7254
e-mail: richard.easingwood@stonebow.otago.ac.nz
I agree with the previous posts regarding the supposed "safe
limits" as
being too high. I too have become sensitized from years of
exposure to low
levels. If I catch even a whiff of glut. my throat becomes
irritated and I
cough for a couple of days. I insist that it always be dealt
with in a
fume hood, no exceptions. Just my two cents worth.
cheers
ed
Edward J. Basgall, PhD
The Pennsylvania State University
Surface Chemistry Group
ejb11@psu.edu
Materials Research Institute Building Ph:
814-865-0493
University Park, PA 16802-7003 FAX:
814-863-0618
sensitive
to glut, not so bad I can't use it, but gloves and fume hoods are
a *must*.
Anyone not sensitized should demand them to prevent getting
sensitized.
Same for formaldehyde.
The problem doesn't end with these compounds, though--I've become
sensitized to cacodylate and MS-222 (an anesthetic), and others
have
remarked on becoming sensitized to embedding resins. I would
think the
chronic exposure limits are too high generally, but in all cases
gloves and
fume hoods should be used more than they are.
The question is, what is to be done with anatomy classes? I've
taken to
recommending that any women who are pregant or working on it to
seriously
consider dropping the course.
Phil
P.S. There was a thread awhile ago on what gloves to use with
what
chemicals--was there a definitive list that came out of that
discussion? I
know glut goes through latex like the glove isn't there. P
} Sic Hoc Legere Scis Nimium Eruditionis Habes {
Philip Oshel
Station A
PO Box 5037
Champaign, IL 61825-5037
(217) 355-1143
oshel@ux1.cso.uiuc.edu
I agree with what was said in this posting, except that in my
case I would have to substitute formaldehyde.
The sensitisation occurred one evening in 1972. I spent several
hours over a dissecting microscope working on a fish head/brain
preparation after
perfusion with 4% formalin + 5% glut. in a small room with no
ventilation.
About 3 am I woke up with really burning eyes. I was taken to the
(fortunately local) eye hospital immediatelt only to be flushed
out (not nice) and
given eye drops against infection. My eyes were covered for about
4 days. I couldn't go back to contact lenses for years
afterwards.
I am now overpowered by low concentrations of formaldehyde. Even
0.04 ppm(measured by a meter) seems far too much too me and my
eyes inflame, my
throat becomes sore and sometimes my sinuses will become
irritated if I stay there too long. In our lab, it is only used
in a fume cabinet/cupboard or
under a strong extractor fan in one place.
The funny thing is, I am not sensitised to glut.
Best wishes - Keith Ryan
After reading the Glutaraldehyde/formaldehyde safety discussion,
I've
decided to add my note of warning. After working with GAL and
formaldehyde and other chemicals of the TEM trade for 30 years
with
only slight reactions to them, I was exposed to a major
formaldehyde
spill. Not only did I suffer major respiratory tract irritation,
but
my lung collaped and I soon developed hypersensitivity to a
wide range of volatile organic chemicals, including formaldehyde,
GAL, liquid epoxy resins, solvents, 2-mercaptoethanol, pesticides
(including herbicides), auto exhaust, etc. When exposed to these
I
get headaches and "fuzzy" in the head almost instantly, and a
delayed
hypersensitivity reaction in my pleural cavity about 30' to 2 hr
later that is extremely painful. This lead to further
pneumothoraces
until I had lung surgury. Our hypothesis is that I have
developed an
immune response to formaldehyde-altered proteins of my lung or
pleural cavity, as well as the limbic system (neural) response
often seen in others with chemical hypersensitivity.
Needless to say, I recommend keeping your exposures to a minimum.
All use of aldehyde fixatives should be in a well-functioning
fume
hood. Anatomy classes should have individual fume hoods for each
dissection station and/or switch to non-aldehyde fixed cats for
example (we did both). Incidently, my unofficial survey of
former
occupations of persons with MCS indicates that histology
technicians
have the highest incidence and some formal surveys show similar
results.
It's definitely less fun trying to function (and very difficult
to
do research) in today's chemically-dependent society when you are
hypersensitive to nearly every volatile organic chemical around.
-BE CAREFUL WITH THE GAL AND FORMALDEHYDE!-
-Dennis
Dr. M. Dennis Goode Phone (301) 405-6917
Department of Zoology Fax (301) 314-9358
University of Maryland e-mail goode@zool.umd.edu
College Park MD 20742
Ozone sounds good in theory. I'd certainly prefer it to
formaldehyde, but is that a "Hobson's choice" (choosing between
the
lesser of two evils)? Can you comment on the effects of ozone on
lung tissue?
-Dennis
> Date: Mon, 16 Jun 1997 07:46:30 -0400 (EDT)
> From: BNguyen260@aol.com
> To: goode@zool.umd.edu,
Microscopy@sparc5.microscopy.com,
> richard.lander@stonebow.otago.ac.nz,
KPR@wpo.nerc.ac.uk
> Subject: Re: Glutaraldehyde: safe limits -Reply
> To all,
>
> After read all the posted messages about Glutaraldehyde and
Formaldehyde with
> their hazadous fumes, we Electron Microscopy Sciences want to
remind you all
> that we have been introducing in our catalog, in the Safety
Section, the
> LAB-AIR System - an Electronic Air Purifiers, which complied
with OSHA
> Regulations and minimizes Occupation Exposure To Toxic Vapors.
The System
> that destroys the odors and fumes, and doesn't just mask them.
> Electronic Air Purifiers produce a controlled level of Ozone
(O3)
> electrically by converting molecules of Oxygen (O2) into
molecules of Ozone
> (O3).. Ozone, sometimes called activated oxygen, as part of the
process of
> returning to oxygen, casts off its extra atom. That extra atom
combines with
> the molecule of the odor's source and thereby destroys the odor
by oxidation.
> Once Ozone's extra atom is consumed fresh air is leftbehind
which was created
> by a natural process.
> For instance:
> HCHO + O3 = HCOOH +
O2
> Formaldehyde Ozone Formic acid
Oxygen
> HCOOH + O3 = CO2 + H2O
+ O2
> Formic acid Ozone Carbon dioxide * Water*
Oxygen*
> * All Harmless Gases.
> We are not intended to introduce our product on the site, but
we thought this
> messages are helpfull to all of our Scientists and Technicians,
whose is
> dealing with chemicals daily in theirs enclosed labs.
> For more information, please contacting us at 1 800 523 5874
>
> Bang Nguyen
> Electron Microscopy Sciences
>
>
Dr. M. Dennis Goode Phone (301) 405-6917
Department of Zoology Fax (301) 314-9358
University of Maryland e-mail goode@zool.umd.edu
College Park MD 20742
My E-Mail system has crashed a couple of times lately, and I
believe that I
have lost some messages.
First, based on OHSS (Occupational Health and Safety Standards)
provides
that no employee should be in an environment where the ozone
level on average
is more than 0.1 parts-per-million for more than 40 hours per
week or more
than average of 0.3 parts-per-million for more than 15 minutes at
any one
time. ( Because of the limitation of the site, we can not display
a chart ,
which is shows the Human Tolerance for Ozone). The LAB AIR Units
are designed
to produce the ozone level less than the limitation, and to
operate within
the OHSS guidelines.
You should know that even with strong odor, the amount of ozone
required to
mask them out is only approximetely 0.04ppm, medium odor approx.
0.03ppm and
light odor approx. 0.02ppm.
Secondly, You are not breathing ozone air, you're breathing
normal air, the
Lab-Air turns on only when needed and ozone air is produced by
the lab air
just enough to mask (oxidizing) the odor sources. For instance,
you're
drinking water, not drinking chlorine, but in the water that you
are drinking
has some amount of chlorine, which is used to remove bacterias.
When you do an embedding mixture, for instance !00ml
Araldite-Epon mixture,
you are using only maximum 1.5% of DMP-30 (1.5ml) to make the
whole 100ml ot
that mixture turn into a solid plastic block.
Back to ozone air, you need just a small amount of O3 to
oxidize the
unwanted odor or unwanted chemicals which presence inside the
room. Each
Lab-Air has the timer to set the length of time which you want
the Lab-Air to
work, as well as setting for ozone to control the ozone air
output, but the
ozone output never exceeds the limit which is the Human Tolerance
for Ozone.
Thirdly, the O3 is unstable, which means it has a very short
life, by its
very nature Ozone will revert to oxygen within a short period of
time.
BNguyen260@aol.com
Richard, I was reading my wife's e-mail and noticed your
question. I am an
occupational hygiene chemist and have been measuring
glutaraldehyde levels
in hospitals and clinics throughout Queensland for about six
years, and I
agree that 0.2ppm is far too high. Following representations from
a number
of people, myself included, Worksafe Australia have reduced the
limit to
0.1ppm . I dont consider myself to be particularly sensitive to
glutaraldehyde, but I know that 30mins exposure to 0.09ppm will
guarantee a
headache. In my experience, to avoid complaints from staff, the
level should
be kept below 0.03ppm if possible, although I did come across
someone who
became sensitised at 0.02ppm while working in an X-ray dark room.
X-ray film
fixer contains a small amount of glutaraldehyde some of which
gets blown
around the room when the film is dried. I usually use a
Glutaraldemeter for
the measurements, and it is quite good unless there is alcohol in
the room.
However, it is so obvious when the meter starts to wind off
scale, that it
is not a problem.
The Glutaraldemeter is good in that it gives spot measurements,
other
methods I have used such as 2,4DNPH tubes give an average reading
over time,
but are not so good where glutaraldehyde is being used
sporadically.
Imust say that I havent come across an EM lab without a fume
hood, and so
they dont seem to have your problem.
Hope this helps.
George Lee
Chemist- Occupational Hygiene
Queensland Health Scientific Services
PO Box 594
Archerfield 4108
Brisbane Queensland
Fax +61-7-32749008