BW Chemistry and Disposal

Film Photography & Darkroom discussion

Moderator: Keith Tapscott.

Post Reply
brianentz
Posts: 3
Joined: Wed Mar 25, 2020 5:37 pm

BW Chemistry and Disposal

Post by brianentz »

This has probably been discussed before, but I am new here.

I just bought a full set up of Eco Pro BW Chemistry, including their XTOL developer, and am anxious to get going. I live in an area with septic tanks and the Haz Mat disposal site locally isn't darkroom chem friendly. Just wondering which, if any, of the chemicals could be responsibly disposed down the drain. I'm assuming Photo Flo would be safe. Just wondering if any of the other chemicals could be treated in such as way (diluted, exhausted, etc...) to make them safe for disposal. If I have to I will haul of it it a disposal site - a far drive away, but was wondering if anyone had any input on how to minimize this - especially since I am using more environmentally safe chemicals.

Digitaltruth
Site Admin
Posts: 292
Joined: Mon Aug 16, 2004 8:24 pm
Contact:

Re: BW Chemistry and Disposal

Post by Digitaltruth »

In most cases it is safe to pour ECO PRO chemicals down the drain as long as you run water to dilute them during disposal.

ECO PRO chemicals are free of Metol, hydroquinone, borates (except powder film developer), phosphates, acetic acid, perfume, dye and non-biodegradable organic compounds EDTA and DTPA, so are safer than any other commercially manufactured range of B&W photo chemicals.

The only way that you can determine what your legal requirements are for disposal is to contact your local environmental authority. There is no wide-ranging legal guideline as requirements are determined by local waste regulations.

The MSD sheets for ECO PRO are available here: https://www.digitaltruth.com/products/d ... and=ecopro
Digitaltruth Photo
https://www.digitaltruth.com

brianentz
Posts: 3
Joined: Wed Mar 25, 2020 5:37 pm

Re: BW Chemistry and Disposal

Post by brianentz »

Thanks. That is helpful. It states that the photo flow is non-hazardous, as I would’ve thought. So down the drain it goes. From what I understand the danger is that the silver collects in the waste. Unless I am mistaken, silver does not make it past the fixer? Does it also collect in the developer or stop bath?

Digitaltruth
Site Admin
Posts: 292
Joined: Mon Aug 16, 2004 8:24 pm
Contact:

Re: BW Chemistry and Disposal

Post by Digitaltruth »

Silver is inert and non-toxic and is not considered an environmental risk, although it could potentially pose a risk to marine life in large doses. There is a popular misconception that silver is dangerous because it is a heavy metal, but this is not true. However, there are guidelines for safe amounts of silver in drinking water and the potential risk to marine life should not be disregarded. For more information, there is a good article here:

https://sites.dartmouth.edu/toxmetal/mo ... on-silver/

Fixer removes the unexposed silver halides from the emulsion, so it should be safe to assume that the only significant amounts of silver in the solutions would be found in fixer, although some residual amounts could be in other solutions, particularly from carryover into the hypo clear or final wash.
Digitaltruth Photo
https://www.digitaltruth.com

Post Reply