Is Metol toxic?

[miha]

There are some chems you should probably really avoid, like Selenium toner

Still, every time someone questioned the use of selenium toner their threads were met with disapproval.

 

[Doremus Scudder]

Still, every time someone questioned the use of selenium toner their threads were met with disapproval.

It's the proper handling of selenium toner (and every other darkroom chemical) that really matters; not whether to use it or not.

Selenium toner requires certain precautions, like gloves, tongs, etc. for the liquid concentrate and working solutions - respirators and ventilation hoods if mixing dry chemicals (not recommended for amateur users! - But manufacturers certainly take the needed safety measures).

Disposing of chemicals safely and properly (and in accordance with local regulations) is important too.

If you can be confident and comfortable fulfilling the necessary precautions and proper use of these chemicals, including selenium toner, then there isn't a real problem. It is misuse, carelessness and improper disposal of chemistry that causes the problems.

The "disapproval" you refer to is likely just people saying that selenium toner is just fine if you use it properly. I ascribe to this point of view. The same applies to Metol (see, I'm getting back on topic ).

Best,

Doremus

 

[ChrisK]

A friend/colleague/mentor developed a quite serious allergy to metol. He has said that when much younger he was careless in printing and often did not use gloves or tongs. Net result: I knew no one happier at the advent of digital than he. He never exclaimed "digital has so much control!", he was just happy to shoot and print again.

 

[MattKing]

As may be obvious now, a better question for the thread title might be "How toxic is Metol?"

 

[DREW WILEY]

The mutagenic effects of selenium, especially on wildlife, are well documented. The EPA monitored hospital usage of it mostly, and didn't have time to worry about relatively tiny home darkroom amounts.
I don't use selenium toner much anymore, preferring the look of gold chloride and brown sulfide toners instead.

I don't know how toxic metol is. I don't know how toxic poison oak is either. But I do know it's wise to avoid direct contact with either.

 

[miha]

The "disapproval" you refer to is likely just people saying that selenium toner is just fine if you use it properly. I ascribe to this point of view. The same applies to Metol (see, I'm getting back on topic ).

Best,

Doremus

I'm afraid the comments one can read on this is that KRST is fine when used as an anti dandruff shampoo or as a tomato fertilizer...

 

[Rudeofus]

If you can be confident and comfortable fulfilling the necessary precautions and proper use of these chemicals, including selenium toner, then there isn't a real problem. It is misuse, carelessness and improper disposal of chemistry that causes the problems.

The "disapproval" you refer to is likely just people saying that selenium toner is just fine if you use it properly. I ascribe to this point of view. The same applies to Metol (see, I'm getting back on topic ).

The original question revolved about an environmentally very conscious youngster, who would show more interest in analog photography, if such an endeavor did not create too much toxic waste. We're also not talking about large labs dumping multiple gallons at once.

In order to achieve this, that youngster can use Metol/HQ/AA/HQMS/Pyro/Catechol without any reservations (personal safety protections notwithstanding), but Selenium toner should be off the list. I don't think used fixer is much of a problem, there is enough sulfide in any septic system to take care of the few grams of silver you dump in there.

 

[grat]

I think this thread got sidetracked on "how toxic" is Metol, rather than "What's the environmental impact". A couple of posts suggest that it breaks down rapidly "outside", which is good. Some of the chemicals from film that have been banned have been banned not because they're toxic, but because once they get into the environment, they stay there, and the cumulative effect is very bad. With the exception of silver (which is "bad" because it's such an effective anti-bacterial), most photo chemicals seem to break down during use, or are easily neutralized.

Personally, I distrust these statements that "X" requires "Y" amount of water-- while true, it seems to ignore the fact that the water is typically not destroyed, and makes it's way back into the environment. If I cut open a smartphone, I'm not going to find several dozen gallons of water lurking inside. A datacenter may require thousands of gallons of water per day, but that water is not consumed, and it is not single use.

 

[koraks]

A datacenter may require thousands of gallons of water per day, but that water is not consumed, and it is not single use.

Around here, datacenters use either tap water or they pump up water from underground aquifers. Most home darkrooms I know of also use potable tap water. In many places, this supply is under pressure. Water that's used goes through wastewater treatment plants and is discharged into surface water bodies, generally rivers. From there, it flows into the ocean where it of course ceases to be potable water. Effectively, for many parts of the world, the drinking water system is an open-loop system that systematically drains aquifers in an unsustainable fashion. Places where the loop has actually been closed can be counted on one hand, are experimental in nature and very limited in size and scope. The notion that the water is returned to the environment is technically true, but by the same logic, burning coal and oil also just releases natural carbon back into the ecosystem - so no problem, right!?

 

[Vaughn]

If hydrogen-powered vehicles really catch on, there will be a lot of water 'destroyed' -- although some will reappear at the tailpipe.

It is removing water from a watershed and not returning it clean (or not at all) to the same 'height' of the same watershed that creates the most issues for that watershed. Other issues are that some water being pumped out of the ground is 'fossil' water that will not be replaced for tens of thousands of years -- water from the melting glaciers of the last ice age. Then there is the Central Valley in CA where the ground elevation has dropped 10s of feet due to the pumping of ground water for farms and towns...collasping the aquafer so that it can never be filled. Nothing is simple.

Like poison oak, metol is an allergen. The responsible chemical in posion oak is a toxin, metol is not a toxin (by definition). Both could be considered toxic. Fun word-stuff.

 

[DREW WILEY]

But poison oak is also one of the prettiest colors of late summer and autumn. There was an older couple up the hill back in the woods - really nice people, but who complained that nobody liked to visit them. They had moved into the area from Minnesota. I stood in front of their house. The man asked me, What is this lovely vine I found in the woods? He had made an intricate arbor of it all around his entry door and front windows. Not everyone is allergic to poison oak; some terribly are, and others are sensitized only by burning it, or if it breaks the skin.

 

[Vaughn]

I love the way poison oak climbs 30 feet up the redwood trunks down south (Humboldt Redwoods State Park, for example). This time of year the leaves turn that pretty color and gently rain down all around you when the wind picks up through the trees! Photographing down there in the winter is not much better -- one can get poison oak rashes from just the vines -- with no leaves-three to warn you!

The number one way I use to get poison oak is from petting dogs and working with mules -- they get into it then transfer the oil to me.

 

[DREW WILEY]

I'm one of those immune to it unless is breaks my skin. But my sister is so sensitive to it that she can get a rash just from a breeze across the road through poison oak. I knew someone whose career was removing it, suited up in Tyvek. You sure as heck don't want to burn it, however, and get the smoke in your lungs. Right now, it's the wild grape vines and leaves climbing way up the trees which are in color. I managed to get out one warm afternoon and do a little shooting, but am still trying to get over a cold - first one in 15 yrs - so am mainly staying indoors.

 

[DREW WILEY]

Domestic use salt contains additives, often including a little titanium oxide whitener as well as iodine. For darkroom use, specify pure sodium chloride instead.

 

[Vaughn]

Domestic use salt contains additives, often including a little titanium oxide whitener as well as iodine. For darkroom use, specify pure sodium chloride instead.

Or buy Kosher salt...

 

[Augustus Caesar]

Almost everything is toxic to some degree, depending on the amount. We need trace amounts of many metals and minerals.

 

[pentaxuser]

, but Selenium toner should be off the list.

Are you talking about selenium liquid toner that you can buy from Ilford or making it from raw chemicals? If it is the former case this Ilford video on its use didn't seem to indicate any reason why it should be off the list. Yes she suggests taking the precaution of gloves and safety glasses but is that a reason for it being "off the list"?

Yes it should be properly disposed of as should several chemicals in regular use There didn't seem to be any reason why a responsible adult who is a newcomer to photo chemicals used for processing should not be able to use it



pentaxuser

 

[DREW WILEY]

Take a look at many of the common chemical products under kitchen and bathroom sinks, or on garage shelves. Now that is spooky! And think about all the millions of gallons of Round-Up being mindlessly sprayed. A darkroom might be one of the safer places.

 

[Rudeofus]

Are you talking about selenium liquid toner that you can buy from Ilford or making it from raw chemicals? If it is the former case this Ilford video on its use didn't seem to indicate any reason why it should be off the list. Yes she suggests taking the precaution of gloves and safety glasses but is that a reason for it being "off the list"?

"Properly disposed" means in my home town "bring pH to neutral, then dump into the sewer". This works for developers, C-41 and E-6 bleaches and whatnot, but in case of Selenium toner toxic heavy metal gets ultimately dumped into the environment.

One can argue "how much Selenium will this be anyways over time?" and keep going, but the original question was quite specific and "don't use Selenium toner" answers this specific question IMHO.

 

[pentaxuser]

I was simply curious so thanks and should be "off the list" for everyone on the basis that it is a chemical that can be genuinely singled out from all the others as incapable of safe disposal or might it be that that in your area the disposal method as you described is not the best/safest method

pentaxuser

 

[alanrockwood]

Almost everything is toxic to some degree, depending on the amount. We need trace amounts of many metals and minerals.

That's almost an exact quote from Paracelsus, sometimes rendered as "Sola dosis facit venenum" ("The dose makes the poison").

By the way, even selenium is an essential nutrient, though only in very small quantities. In large quantities it is toxic.

 

[Rudeofus]

I was simply curious so thanks and should be "off the list" for everyone on the basis that it is a chemical that can be genuinely singled out from all the others as incapable of safe disposal or might it be that that in your area the disposal method as you described is not the best/safest method

"My area" is an affluent town with more than a million inhabitants in western Central Europe. If the municipal facilities in my town treat photographic waste like this, then I would expect that's as close as "top of the crowd world wide" as it gets. If you are an old cynic like me, you can probably resort to "the world can handle a few grams of Selenium every so often.".

The premise of this whole thread, however, was "Someone wants to be as environmentally conscious as possible", and in this case Selenium toner would be one of the first things off the list. Bichromate bleach and E-6 reexposure bath somewhere next.

 

[pentaxuser]

Yes the OP did use this phrase: "I am trying to get my black and white photography as green as possible. Yah, I know that sounds funny."

I suppose it all depends on how far you wish to take it and I agree it is impossible to know what the limit of "as green as possible" is from this statement In the case of Selenium toner and indeed other chemicals used in photography the "green as possible" route might be to ban the sale of it completely or indeed the sale of anything else whose use "purely for pleasure" can be shown to be harmful in even the slightest way

Or do we go the route of trying to weigh the extent of the harmful effects against the likely extent of that chemical's use and then deciding if those limits of use can reasonably to coped with by "the world as a whole"

I think we can agree that in its liquid form and with the use of gloves and safety glasses to prevent splashes in the eyes Selenium can be handled perfectly safely

pentaxuser

 

[Rudeofus]

Yes the OP did use this phrase: "I am trying to get my black and white photography as green as possible. Yah, I know that sounds funny."

I suppose it all depends on how far you wish to take it and I agree it is impossible to know what the limit of "as green as possible" is from this statement In the case of Selenium toner and indeed other chemicals used in photography the "green as possible" route might be to ban the sale of it completely or indeed the sale of anything else whose use "purely for pleasure" can be shown to be harmful in even the slightest way

Or do we go the route of trying to weigh the extent of the harmful effects against the likely extent of that chemical's use and then deciding if those limits of use can reasonably to coped with by "the world as a whole"

I don't judge people, who use Selenium toner, and have a bottle in my darkroom as well. All I did was answer the question "If analog photography had to go greener, which are the current chems you'd ban fist?", and the three I already mentioned would be top of my list. I regularly use Stannous Chloride in my E-6 reexposure bath, I rarely but do use Selenium toner, and I have an unused stash of bichromate somewhere. I also stated, that Metol is specifically not on that list, and neither are other development agents, which a regularly described as dangerous and toxic. These are toxic for us, if we are careless in our darkroom work, not not an environmental problem.

I think we can agree that in its liquid form and with the use of gloves and safety glasses to prevent splashes in the eyes Selenium can be handled perfectly safely

Selenium toning was part of the regular archival darkroom printing process, so obviously it can be done in a personally safe way. The original question revolved about environmental impact, which is a completely different story.

 

[john_s]

.......



Selenium toning was part of the regular archival darkroom printing process, so obviously it can be done in a personally safe way. The original question revolved about environmental impact, which is a completely different story.

And as Doremus has said, you can use the same batch with replenishment for a very long time, so that would be ecologically responsible. You don't even need to filter it if you have enough in a large bottle and allow the precipitate to settle.