Toxicity of hand processing photopolymer plates


Currently i’m hand washing photopolymer plates. From what I’ve researched online, water washout plates (eg. toyobo printight) are non toxic and not considered to produce hazardous waste.

However, when I do handprocessing, there is that distinct pungent smell of the unexposed photopolymer being washed out.

Is it really that non-toxic? For some reason there’s this nagging feeling that the pungent smell can’t be good for me.

Appreciate any advice.


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You should pose this question to your plate provider. If you are hand-washing the plates, your volume will not be such that it poses a threat to your city’s wastewater plant, but I do believe in some commercial operations steps must be taken to separate the unexposed polymer materials from the waste stream.

The MSDS indicates that some skin irritation and dermatitis can occur with contact with the skin, so recommends using impervious gloves when contacting the washout solution. There are chemicals and photo-initiator which can be disruptive if not removed from the wastewater.

It is my understanding that the exposed and washed-out plates are no longer a risk to the environment.

See MSDS at

John Henry

If you are concerned, wear gloves. The MSDS does indicate such barrier protection for your skin.
I’ve heard from people who insist it is benign and biodegradible (if also a plumbing problem), and others who believe it is carcinogenic.Never saw an independent, credible source for such assertions.
The truth is somewhere in between, and gloves are cheaper than The Truth. On the other hand, I’ve been doing bare-hand processing for 25 years and wil let you know of the first sign of dermatitis or cancer. So far, just insanity, but we can’t blame photopolymer above other potential causes.

Especially because you were probably insane to begin with, or you wouldn’t be in this field ….


The EPA was in my shop twice in the last year and they definitely did not like at all the bath in my photopolymer plate machine, and this was based only on fumes it was giving off (based on that morning’s use). It was the only thing in my entire print shop that caused their machine to go off. Note that they were not there to investigate photopolymer nor print shops, but rather possible seepage from a near by fifty year old dump site of PCPs.

While for many years it was said that photopolymer is non-toxic, one company, Toyobo, now indicates that care should be taken to protect skin during processing.

If you are processing plates by hand I would be doubly cautious in regard to the washing out process.


I’m with P. Imp on this one…. I used to do a lot of hand-processing a few years ago and don’t think it’s terribly toxic. However, the MSDS sheet does recommend wearing rubber gloves and avoiding prolonged skin contact….. so that’s what I do.

The other thing to be concerned about with PP is the environmental effects of dumping the washout water down the drain. Where I live, the Sewer and Water Board believes that PP chemicals disrupt the bacteria in their processing plants…. and thus strictly forbids washing-out into their system. A friend of mine got a nasty letter from them just a few months ago.

I don’t know if they are right in their assertion or not, but I do follow their guidelines to avoid having to pay fines or have my water service cut off. that would cause all sorts of problems, i think.

Never heard that photopolymer was a bacterial/sewage problem, but the silver that washes out of our negatives IS, without question. That’s why hypo/fix must be run through a silver recovery unit. Then the silver sludge can be sold.
The Printer’s Shopper used to sell a gel cubitainer that was supposed to encapsulate any photochemical waste for landfill disposal. More $$ for BS?