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1. LapDigest News for Issue No. 30 Saturday 7/19/97
2. NEW: Dangers of Rock Dust

Subject: LapDigest News for Issue No. 30 Saturday 7/19/97

Instead of publishing the usual Digest, I am publishing a message from
Glen Kuban, a rockhound from the Cleveland vicinity. He talks about the
dangers of fresh-cut rock dust, an important item in lapidary. True, we
usually work under a spray of water, but the danger still exists, and I
hope all of you will read it and remember it.

And also please remember: Each author is requested to write the words
"-- non-commercial republish permission granted --" at the end of every
item submitted. This gives permission for others to use your item for
non-commercial purposes. Then clubs may legally pick up the items and
reprint them in club bulletins, and thus your words may have wider
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each item you submit.
Subject: Dangers of Rock Dust

By Glen Kuban

Keywords: Silicosis, pulmonary fibrosis, lung disease

Many collectors use a mechanical rock saw to cut, trim, or abrade rocks
and fossils in the field or lab. Dangers of this activity include flying
rock chips, wounds from the blade itself or broken blades, and rock dust,
which is extremely dangerous to inhale. Always read and understand the
proper operation of any mechanical tool before using it. Whenever cutting
or grinding rock, wear protective eye goggles. Also wear a good respirator,
or use a dust collection system, to avoid inhaling rock dust, which
accumulates in the lungs and can cause a variety of serious illnesses.

For those not convinced that rock dust is a serious danger, or that they
can get away with not wearing a respirator or working under a hood (if
working indoors), I encourage you to read the messages below. The original
message was posted on 7-14-97 in the Rocks and Fossils Newsgroups, and my
reply was sent to that list as well as the Dinosaur List, VrtPaleo, and
Fossil Nuts.

The original message I am responding to was posted in Rocks and Fossils,
but I am sending my response to other paleo-related lists as well, because
I feel this is an important safety issue. It affects anyone who even
occasionally cuts rocks or fossils, or does fossil preparation work. It
will be very worthwhile if it prevents even one person from suffering lung
problems or dying prematurely. With that deliberately ominous introduction,
let me quote the post that prompted my response:

Pete Richards wrote:

<< Last night I spent an hour cutting sandstone sidewalk >blocks with a
composition blade made of fiberglass and carborundum grit. This is a dry
saw and it was a still night and clouds of dust were all around. Some of
it hung in the air for minutes. I am not really concerned about a one-shot
exposure, but it did make me wonder if this is the size of silica which DOES
represent a health hazard. Of course, I do not know for sure that the fine
dust was silica, as opposed to calcium carbonate (the cement in the
sandstone) or material from the saw blade... >>

It's funny, or really not so funny, that you should write now. I'm
suffering a chronic lung irritation, and seeing doctors now, because of the
results of a similar incident. In short, yes, one or a few exposures to
significant amounts of freshly-cut rock dust can cause serious problems.
Silicosis is only one of many lung problems that can be caused by rock dust,
many of which (like fibrosis) can occur no matter what the composition of
the rock. Wearing a good respirator or hood with dust collector if working
indoors is a must. If you don't have the proper safety equipment, don't cut
the rock!

Unfortunately, I found out the hard way, I hope everyone learns from my
mistakes. About a year ago our fossil club went to Ontario to collect
trilobites, and we took along a diamond rock saw. I only sawed out a few
trilobites for fellow members (without wearing a mask; I forgot to bring
one) and I tried to not inhale the dust. However, large clouds of it were
kicked up each time, and it was impossible to avoid inhaling quite a bit
of it. My the next morning I had significant lung irritation, and have
had it ever since--some days worse than others. I have frequent coughing
and uncomfortable sensation in my upper chest. After this went on a few
weeks, I went to a doctor, not knowing if I had contracted a bacteria,
fungus, or other microbe at the quarry, or just had accumulated too much
dust in my lungs. An x-ray was clear, but that is not unusual in such
cases (it sometimes takes years for fibrosis, TB, cancer, and other
diseases to develop). Apparently the rock dust itself is the cause the
current lung irritation, and it may never get better. In fact, it may
worsen into other conditions, as explained below.

Many people assume years of exposure to rock dust is needed to cause
serious problems, and this is generally true when dealing with wind-blown,
low concentration dust, which usually has already been weathered to some
degree. But not so with freshly cut rock. After I started having my
problems, I began talking to doctors and doing lots of reading. I also
talked to an uncle who used to work in a quarry, and is now dying of
pulmonary fibrosis at the age of 55. I'm now going to his doctor.

It turns out that not only do rock particles of any composition tend to
stay and accumulate in the lungs, but _freshly cut_ rock is the worst,
and extremely pernicious. Even one or a few incidents of significant
inhalation of such dust can cause lung irritation and a start process of
increasingly serious lung damage. The microscopic particles are like
millions of razor-edged shards that damage lung tissue directly, as well
as create conditions promoting the development of TB, microplasms,
fibrosis, and cancer. Experiments with rats and other animals have shown
that inhalation of fresh cut rock dust is far more damaging than worn
rock dust of any composition, and leads to far greater rates of several
diseases, including pulmonary fibrosis and lung cancer. (But even
accumulations of worn rock dust in the lungs greatly increased chances of
lung diseases).

I've also made many fossil molds and casts over the years, and although I
often wore a mask while working with plaster, but sometimes did not. I may
well have accumulated plaster in my lungs as well, which may have
contributed to or aggravated my lung condition. Plaster hardens when in
contact with moisture, wherever it occurs, including one's lungs. But I
did not have the constant lung irritation until after the Ontario trip
using the rock saw (on hard shales and siltstones), and have had it ever

I have another appointment with a pulmonary doctor on Thursday, but from
what I have learned such damage is generally irreversible, the best I may
hope for is to have my condition not get worse. I may have to live with
lung irritation and chronic caugh for the rest of my life, plus increased
chances for the serious conditions I listed above.

So PLEASE, whenever you are cutting or grinding rock of any kind, ALWAYS
wear a respirator (not just a cheap dust mask). If working indoors, use a
dust collecting hood, or don't do it. Your health is not worth any rock or

There are serious inhalation dangers in the lab also, including solvents,
urethanes, glues, and other chemicals used on prep work. These too can
have accumulative effects, and lead to a variety of heath problems. Work
with such chemicals only with very good ventilation, or under a hood, or
don't do it. Again, a rock or fossil is not worth your health.

If I scared anyone, I can't feel too bad, because I wish someone had scared
me before I did what I did, and may have to pay the price the rest of my

Pete, in your case, I hope you do not have any problems, and can only urge
you not to do it again, at least not without wearing a respirator. The
dust you created by cutting sandstone probably included a mixture of
siliceous sand particles, calcium carbonate particles, (from the cement
between the sand grains), and fibers from the fibrous saw blade. All could
be dangerous to inhale.

Thank you.

Glen Kuban


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