This is the blog for IAB

The mission of the International Association of Bryologists (IAB), as a society, is to strengthen bryology by encouraging interactions among all persons interested in byophytes.

Monday, November 9, 2009

RE: BRYONET: Hoyer's Solution & chloral hydrate

BRYONET

Dear Des et al. The recipe for Hoyer's Solution and notes on its use
were presented by LE Anderson in Bryologist 57: 242-244 (1954).

I still use it and do not know of anything else that works as well. I
think Richard Zander has published some notes on alternative mounting
media. There are also some notes on alternatives (but one of which also
contains Chloral Hydate) in the introduction to DG Catcheside's Mosses
of South Australia.

As Cynthia Galloway correctly points out the danger with Hoyers (or
making Hoyers) is that it contains chloral hydrate. You can google a
MSDS (Material Safety Data Sheet) for chloral hydate. The Oxford Univ
MSDS gives the ORL-RAT LD50 480 mg kg-1. (ORL=Oral, RAT=rat, LD50=the
dosage that killed 50% of the rats)

So, if my arithmetic is correct, if you weigh 70 kg, you would need to
ingest 33.6 grams of choral hydrate to have a 50% probability of death
(assuming you were a rat).

According to Anderson's recipe there are 0.2 grams of chloral hydrate
per ml of Hoyer's Solution. Therefore it you imbibed c. 160 mls of
Hoyer's Soln you would have a high likelihood of not seeing the next
sunrise.

The Oxford MSDS recommends safety glasses and ventilation when handling
CH. It is listed as a skin, eye, and respiratory irritant. I would also
wear gloves.

I always take care when using Hoyer's, and make a point of rinsing my
hands if I contact it. But I do still use it.

Hope this helps.

Allan Fife
------------------------------------------------------------------------
Bryonet is a service of the International Association of Bryologists (IAB)
and is administered by Janice Glime <jmglime@mtu.edu>
through Michigan Technological University
IAB Officers:
President Jeff Duckett <j.g.duckett@qmul.ac.uk>
Secretary-Treasurer Jim Shevock <JShevock@calacademy.org>
First VP: Masanobu Higuchi, Second VP: Jiri Vana
To join IAB ($11 per year), contact Jim Shevock <JShevock@calacademy.org>
IAB website: http://www.bryology.org/
------------------------------------------------------------------------

3 comments:

  1. Is there an MSDS available for Hoyer's Solution?

    ReplyDelete
    Replies
    1. The danger of Hoyer's Solution is jail time if you don't have a narcotics permit (in U.S.A.). It's harmless in tiny quantities.

      R. Zander

      Delete
  2. Those who avoid glycerin jelley, the best alternative to Hoyer's Solution, should try Water Glass Glycerin mountant.
    See
    http://www.mobot.org/plantscience/resbot/Meth/GlycerinJellyB.htm

    ReplyDelete

Recent Literature on Bryophytes

BryoSphere

Bryology in the cybersphere.

Follow BryoSphere on

Follow BryoSphere on FriendFeed

Followers