I am completely new to this developng game following the gift of an enlarger from some friends. I have set up a darkroom but am concerned about the effect of throwing out the used chemicals. I understand that I can keep the fixer and use it again but the developed goes off and should be disposed of. I never know what to do with it and have been pouring it down the sink with plenty of water. What environmental pollution am I causing by doing this?

-- Catherine Pugsley (martinandcat@hotmail.com), November 27, 2000

Answers

Here is Kodak's response. http://www.kodak.com/cluster/global/en/service/faqs/faq5026.shtml

-- Chris Hawkins (peace@clover.net), November 27, 2000.

Kodak, of course, is a manufacturer, and as such, they are not neutral about this. I found there are considerable differences in the statements published by the manufacturers, and also in legislation of different countries. Here are some facts:

Developer is a reducing agent, which means it consumes oxygen dissolved in the waste water. That oxygen, however, is necessary for bacteria to be able to degrade the chemicals.

Many of the compunds in photographic chemistry are also toxic and/or carcinogenic. So in my eyes, it is not at all clear that they are easily degraded in waste-water plants, as manufacturers routinely claim.

Fixer contains silver. Silver has a so-called is a heavy metal and has an oligodynamic effect, which means that in its presence, bacteria will not survive. I have read a Kodak publication on silver in the environment, and they simply state that in the form in which silver is present in used fixing baths, it is not a big problem as most of it is precipitated. As the concentration at which silver kills bacteria is very low, I have my doubts about this statement, too. Also, silver resources are not infinite, and once silver has gone down the drain, it's lost, and we are one step closer to more expensive photo material.

Selenium is a natural TRACE element, and you need a certain amount of it, but it's also highly toxic, and the line between the good effects and the bad ones is extremely thin. I think even Kodak concede that selenium toner shall not be disposed of via the sewer.

So we are actually left to guess. In my country (and I think this applies to most of Europe), it is forbidden anyway to dispose of darkroom chemicals via the sewer. You have to collect them and bring them to a toxic-waste collection point for incineration. (They are available almost everywhere.)

For prints, there is an almost non-toxic developer. That is Agfa's Neutol Plus, where the developing agent is vitamin C. There are probably other less-toxic developers, but photo chemistry remains a pollutant, and if your conscience nags you to act responsibly, I think you won't get around collecting your waste for an ordered disposal.

As for silver: I would try to find someone who's willing to desilver your fixing agents, or use metallic replacement cartidges. (They were an issue from time to time in one of the forums.)

-- Thomas Wollstein (thomas_wollstein@web.de), November 27, 2000.

In the U.S. or at least my area, incineration is not used for disposal purposes, air pollution. Generally you are disposing your developer with your stop bath which has the effect of stopping the chemical action and balancing the ph. According to the people at my local waste water treatment plant, they have more trouble with ordinary laundry detergent. If you really don't want to pour it down the drain, you could buy a 5 gallon plastic tank like those made for water or gasoline and pour your developer into it at the end of your darkroom session. Leave the cap off so that the water will evaporate out. When the container is full of dry chemical, seal and find some place to dispose.

-- Jeff White (jeff@jeffsphotos.com), November 27, 2000.

I have been simply continuing to use the same selenium toner, but topping it up with freshly mixed toner at the same dilution when it drops too far below the top of the bottle. I am not sure if it builds up other chemicals that might cause a problem for my prints, but I do a thorough soak in hypo clearing agent and a long wash after toning.

For my fix I purchased a small silver recovery unit for about $35. Once I have removed the silver, I simply pour the remaining liquid down the drain.

Most developers oxidize rapidly and are not much of a threat to the environment--I neutralize them with the acid stop and pour them down the drain as well.

I have a septic system, and have been doing this for 15 years with no apparent deleterious effects.

Other solutions, such as gold toner, copper toner, and anything else with heavy metals should probably be disposed of as hazardous chemicals.

-- Ed Buffaloe (edbuffaloe@unblinkingeye.com), November 27, 2000.

As others have said, except for metal based toners, photo chemicals are biodegradeable. As Thomas points out, they do place a chemical oxygen demand on the waste treatment system. In the US, most waste treatment plants do continuous aeration of the waste to deal with this for ALL the stuff in the waste stream. But to help, pre- oxidizing is a good idea. For developer, just leave it in a pan for a day at the most.

The silver is fixer is not in a biologically active state, but silver recovery is a good idea. Porter's (www.porters.com) sells the silver recovery setup Ed talks about. The neat thing is when you fill it up, you ship it back to the manufacturer and they pay you for the silver.

There is a good site called TerraGreen (www.terragreencom) that talks about this, and since it is not a manufacturer of photo chemistry, the concerns Thomas has about the sourse are moot. BTW he is no longer in business, so don't try to order any of his products.

-- Terry Carraway (TCarraway@compuserve.com), November 27, 2000.

If you're worried about environmental effects of developers, I think Kodak developed XTOL to be somewhat more "friendly" than some other developing agents. It's based on ascorbic acid (vitamin C) though it does also contain smaller amounts of less desirable organics.

There are other similar formulations (e.g. Mytol - see http://www.jetcity.com/~mrjones/mytol.htm) which don't have the other organics, but Im not sure if they're commercially available or if you have to make them up yourself.

-- Bob Atkins (bobatkins@hotmail.com), November 27, 2000.

If you are really concerned about your extremely small amount of pollution then please visit your local wastewater treatment plant and talk to the people in the operations section. They will let you know all about the effects on the system. It is something you should be knowlegeable about anyway. I work as a supervisor in a large sewage facility and I can tell you that you addition is not even detectable at parts per billion. James

-- james (james_mickelson@hotmail.com), November 27, 2000.

James is right. It's not like millions of people are dumping these chemicals into the water supply all the time. If home photography was much much more popular then there would be a problem. Worrying about this under these circumstances is over reacting. If we really were causing harm then I'm sure environmentalists would bring it out in the open with scientific facts proving it...

I would be more worried about how your health may be getting affected if you are not being careful with these chemicals.

-- PJT (pjt_123@hotmail.com), November 27, 2000.