# Gum bichromate, how toxic?



## Aimee Danger (Jun 23, 2019)

I’m a semi-beginning gum bichromate printer with a small, windowless studio. I was just laying on a layer of gum emulsion that is 1:2 pigment/arabic: potassium bichromate solution (10%) and I’m wondering whether I need more ventilation. How toxic is the pre-mixed 10% solution? The only MSDS I can find talks about the powder, or how heating it turns it into a toxic gas. But the same can be said of chlorine, so...
Can someone with more experience than me give me a heads up here before I print much more? I’m using rubber gloves and safety goggles, but I also have a respirator if I need it. Do I need it for room-temp, liquid potassium bichromate?


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## compur (Jun 23, 2019)

I haven't done a lot of gum printing but enough to know that potassium bichromate is nasty stuff. 

My opinion is it's better to be "too safe,"  especially in a windowless space.


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