HiUmut
The metol should come in a resealable plastic tub with a harmful Hazchm warning.
It should stay dry in tub for years.
I have bad skin problems so im very careful, but you should use rubber gloves when handling metol or D23.
The risk is of dermatitis or worse.
You need a balance to 0.1 gm easy nowadays mine is silly cheap and good to 0.01 gm.
Have fun Tom A on RFF uses D23 some times. Think he filters it don't recall exactly life he gets.
Ansell used a post borax bath sometimes...
Noel
Coming again to the risc of dermatologic deseases by using photo chemicals.
If you are strongly sensible with your scin you will soon may have additional problems from darkroom work.
Or let me say you will just find out if you get additional problems from this.
Most people don't care about and have
no problems at all.
But this is depending on individual (personal) conditions and on the kind of
chemicals.
In general some photo chemicals are much more harmfull than other typical used photo chems.
If you are still suffering on dermatitis from other reasons I would like to say : "
Handy off from any chemical darkroom expositions - safety first."
What is with the risc to normal people who haven't has any skin problems up to now - and they would like to experiment with some different developer agents ?
You have to notice first : There is indeed a serious risc but this main problem is to comercial use of photo chemicals.
It is depending to the dosis of exposition and most importance to the time of use.
So one could state it is only a question of the time - and you may have serious scinn deseases to over 90%

....
But this is from 8 hours work a day in a comercial facility after a period of 2 -4 years to people with allergenic pre disposition, sometimes after month of work. (The best is in this case after 3 days - therefore people are warned to let it be totaly and chance there profession)
In other cases you should become problems after 9 years?....15 years? 22 years? 31 years? The best case is you are
retired before but there is also a risc to get suddenly scin desease years after retirement

...... to an age of 78...

.
And this is mostly caused from exposition with chemicals over decades during a job in a comercial lab.
AND THEREFORE THERE IS A RISC OF USING PHOTO CHEMICALS.
In a non proffessional use in private darkroom the same risc is on the hand less 98% in comparison.
But you have to notice at least it is never
at 0 %.
For me it is absolute enough to obtain some fundamentariely safety issues to all
chemicals.
And there is no reason to have panic in general.
EXEPTION : YOU ARE A PERSON OF AN
ALLERGENIC TYPE - but this you will normaly find out within some days.
Mostly on the first day

.....
with regards