Neither the calcite nor aragonite forms of calcium carbonate are poisonous
but some animals assimilate high levels of various metals which are or can
be poisonous.  Since calcium carbonate readily dissolves in an acid
environment, those metals tend to become readily available.  Apparently,
some persons are alergic to the proteinaceous portion of the nacre and have
reactions to the dust - headache, nausea, etc.  Dust supression by using
water in all stages of the cutting and polishing processes will minimize
both of those problems and latex gloves will keep the worker "mud-free".
The water also keeps the material being cut from overheating and having
opaque white spots form during grinding and polishing phases.

  _____

From: Avril [mailto:[log in to unmask]]
Sent: Tuesday, November 22, 2005 12:20 PM
To: [log in to unmask]
Subject: Re: abalone dust toxicity


Hello Conchlers,

I had an interesting request for information today.  Judith is allowing me
to publish this to the list as I do not have a good answer for her and I do
not remember this ever being discussed on the list before.

I will forward any and all responses on to her:L

I recently read a comment  on the chat list of the jewellery makers'
website, ganoskin.com.,  stating that the abalone shell is a deadly one to
cut or grind, due to the fact that the body absorbs the dust through the
lungs or skin.  The body then interprets this substance as a sugar  and
sends it to all the organs.  There followed an anecdote about a group of
people dying just a few months after beginning a new efficient process of
cutting abalone shell.   Pustules in the lungs, death due to pneumonia.  It
was also stated that the dust can be absorbed  when suspended in a solution.

Do you know of any writings that go further into the subject of the toxicity
of abalone shell?

I'm going to have to cut some of these shells in my work, and I must find a
safe way to do it.

Thanks so much,
Judith

Judith's source of information can be located at:
http://www.ganoksin.com/search/search.cgi?nocpp=1
<http://www.ganoksin.com/search/search.cgi?nocpp=1&Realm=All&Match=1&submit2
=Search&Terms=abalone> &Realm=All&Match=1&submit2=Search&Terms=abalone

On Judith's behalf, I thank you for all help you may be able to offer,

Avril Bourquin