It is officially estimated that 15,000 workers are killed in the U.S. in on-the-job accidents each year. An additional 100,000 die from chronic disease. While the job-related proportion of the chronic disease group is not precisely known, it has been determined that certain types of workers have higher rates of certain types of diseases. For example, while it is estimated that one out of three Americans will develop some form of cancer, chemical and lab workers will have a 25% greater rate. This should come as no great surprise since chemical and lab workers are more likely to be exposed to a greater number of hazardous substances over a greater length of time than any other group of workers. But other groups are also exposed to these chemicals unknowingly and inadvertently. In particular, photographic lab workers, darkroom hobbyists and the public are exposed to a variety of potentially harmful photographic chemicals on a regular basis.  In addition, cleaning service workers, maids and maintenance workers are exposed to these chemicals even if they don't work directly with them.


In terms of exposure to harmful chemicals, darkroom workers and hobbyists are often in a worse position than chemical workers. Darkroom workers, especially hobbyists, normally receive no training in the proper use of chemicals. Perhaps the main reason for this laxity is that photo chemicals are generally regarded as safe by the photographic community. Many photographers think that since most photo chemicals are diluted before use that the danger is low. But most photographers lack the knowledge necessary to make decisions about chemical exposure. This is shown in the lack of precautions that most photographers take; many immerse themselves, literally, in their solutions and advise their students to do the same.

Contact with high levels of some photo chemicals can lead to acute problems such as burns, dermatitis, dizziness, vomiting, asphyxiation and central nervous system failure. Long-term, low-level exposure can result in chronic problems such as allergic reactions, headaches, depression, lung ailments and cancer. Individuals vary in their responses to chemicals; some are more susceptible to adverse reactions than others. Reactions also depend on the concentrations of the chemicals and the conditions under which they are used.

The greatest danger to darkroom workers and hobbyists is through the inhalation of powders or vapors. Additionally, most chemicals in the darkroom are liquids in open trays or tanks which increases the chance for spills. Absorption through the skin is also easy if the photographer routinely handles chemical-covered films or prints. Chemicals can also be ingested from eating or drinking vapor-contaminated food inside the darkroom.

There are several factors that compound the problem. Many shutterbugs spend incredibly long hours in their darkrooms which are often cramped makeshift quarters at home -- in closets, bathrooms or kitchen counters. All too often these darkrooms provide no safety equipment such as ventilation systems, showers, eye washes or fire extinguishers. Air ventilation is typically non-existent, resulting in chemical levels well above acceptable standards. Any venting is normally blocked at the same time light leaks are checked. And where safety devices are used, there is no way to ensure that the devices are controlling the problem or that they will operate as needed in an emergency. Adequate measurement is expensive and time-consuming so it is often ignored.

Those seeking out information about safety issues in the darkroom will be disappointed. The lack of information is another reason why so many believe that the darkroom poses no danger. There are very few non-technical books that exist on the general health hazards of chemicals. And there are even fewer books that cover the safe use of chemicals in the darkroom. Currently available books on the darkroom barely discuss the matter. The problems are ignored completely or are dealt with by a blanket recommendation that "the manufacturers' precautions be followed". Unfortunately, these recommendations are usually vague, ill- defined warnings, such as "provide adequate ventilation" or "vapor hazardous." They are often ignored because definitions of the terms and hazards are unspecified. What is "adequate" ventilation? How damaging is "hazardous?" Most darkroom workers seem to rely on the rule of thumb "if I can tolerate the odor, the ventilation is adequate." But there are dangers from inoffensive chemicals that aren't offensive: what you can't smell CAN hurt you!

Another problem is that darkroom workers and hobbyists are very likely to deal with premixed packaged chemicals. Since the individual ingredients may not be listed -- particularly if they are proprietary chemicals -- packaged goods can give the appearance of safety. Careless handling results when there is insufficient information about chemicals contents listed on the box. For example, the developing agent commonly known as Metol is sometimes listed under its other trade names, such as Rhodol, Elon, and Pictol, and can also be listed under its chemical names of monomethyl para-aminophenyl sulfate or p-methylaminophenyl sulfate. Without all the possible listings for a chemical, decoding the manufacturer's information may prove fruitless. Perhaps most important of all is that photographers normally combine chemicals, sometimes unintentionally. Without proper training, this can produce unexpected and even hazardous reactions that are more dangerous than any of the individual ingredients alone. For example, mixing an acid with sodium sulfide, a common photographic chemical, releases deadly hydrogen sulfide gas, which is as toxic and acts as rapidly as hydrogen cyanide ("cyanide gas").

In addition, there are dangers that darkroom workers and hobbyists face that lab workers do not. For example, darkroom workers and hobbyists spend most of their time in the dark. This increases the risk of mistakes, accidents and acute exposure. Typically, home hobbyists work alone so that if problems arise they are on their own. And setting up shop on the kitchen counter or the bathroom sink assures that food and other household items will become contaminated.

Various governmental regulatory agencies and standards are designed to protect the public health, but many obstacles lie in the path of accomplishing this goal. Most labs are simply too small to be covered. Governmental standards are helpful for the unregulated lab to follow, but only if they can be measured. For most darkrooms, the additional time and expense of monitoring equipment are seen as prohibitive. Additionally, some of the standards for chemical exposure are set too high for some people to tolerate even though they may cause no actual physical harm. Other chemicals can be tolerated well above the standard level but can cause long-term exposure problems. For example, many people find relatively harmless levels of acetic acid to be very offensive, while they find toxic levels of hydroquinone completely acceptable. Another problem is that many ingredients, such as new or proprietary chemicals, do not have governmental standards. This results in many users assuming there are no dangers.


Chemical threats to the worker or hobbyist largely end when the chemicals are discarded; threats to the environment begin at that point. Photographic chemicals enter the environment through a variety of routes. The most frequent vehicle is the disposal of used chemicals into waste water. Intentional and unintentional venting of vapors into the atmosphere also occurs. Proper methods for disposal of chemicals are rarely covered in photo darkroom books, classes or chemical packages. When it is mentioned, it is typically suggested that the chemicals be dumped down the drain with plenty of water. This practice reduces damage to pipes and sewage systems, but the same total amount of chemical is disposed.

The amounts and types of chemicals that are disposed of by workers and hobbyists can only be roughly estimated. In the U.S., hobbyists and professionals are dumping thousands of tons of various chemicals into the public sewage system every year. This makes photographic chemicals a potentially major health risk for society. The chemicals include a wide variety of toxic substances, such as acids, bases and heavy metals, as well as suspected carcinogens, such as formaldehyde. Undoubtedly the majority of chemicals comes from professional labs -- only the largest of which are regulated by the government. Chemical treatment is often nothing more than dilution by adding water. In the end, just as in the home darkroom, the chemicals from most labs are dumped into the sewage system and are eventually "treated" at a sewage treatment facility, usually through sedimentation and bacterial action. Since the chemicals in the sewage limit its potential for beneficial use, such as for fertilizer, it tends to end up in landfills or dumped into the oceans.


The types of problems caused by photo chemicals are many and therefore require different solutions. Some problems do not yet have perfect answers. For more complete information, consult the resources listed at the end of this article.


  1. Although few books are currently available, some older books dealing with hazards in the darkroom are available through larger libraries and used book stores. Some of the periodicals that focus on the darkroom provide the latest information on new chemicals, equipment and techniques.
  2. Buy a copy of a non-technical book on general chemical safety. Keep it handy and refer to it often.
  3. Obtain the Material Safety Data Sheets from the manufacturers on the chemicals that they use in their products. Chemical companies are required to make these available to the user.
  4. Get government information on recommended exposure levels to various chemicals.

Outside the darkroom:

  1. Do not buy chemicals (or kits that contain chemicals) that you feel are unsafe. Check out the ingredients and their safety before you buy. For example, opt for a developing kit that offers safer formaldehyde substances, such as Fuji's S.A.F.E.R. or Kodak's E-6 Final Rinse over a kit that contains straight formaldehyde.
  2. Only buy kits that are willing to give a listing of their ingredients on the box -- if you don't know what's in it you can't decide if it's safe for you to use.
  3. Support manufacturers that go to the trouble and expense of providing safer chemicals. Write to them thanking them for the safe chemicals that they use. Tell your friends about their products.
  4. Consider mixing your own chemicals. It's fun, easier than you think, much less expensive than buying prepackaged ingredients and you can choose the formulas that contain only the chemicals that you want to use.

Physical safety:

  1. Use the brightest safelights possible for both black and white and color work. This will help prevent accidents. Carefully test your safelight to prevent fogging of the paper.
  2. Wear protective eye gear, gloves and an apron whenever working with chemicals.
  3. Have water available in the darkroom to wash away chemical spills as soon as they happen.
  4. Install ground fault circuit breakers on all electrical outlets. These help prevent shock and electrocution. Test them each time you plan to work in the darkroom. Place electrical cords away from the areas where you may trip on them.

Chemical safety:

  1. Chemical manufacturers usually provide instructions for the use of their product. In these, they specify a concentration that will provide the desired result. They rarely point out that a more dilute solution may provide the same result. You can get more out of your chemicals by using them longer or using more dilute solutions (sometimes longer processing times are needed). This results in less chemical exposure to you, and less chemical being thrown out. Select and use chemicals that offer replenishers; they'll keep your used chemicals in good condition.
  2. Use tubes instead of trays for all processing. Tubes have several advantages. They cut down on the amount of chemical that needs to be prepared, which in turn reduces the amount of chemical discarded. In tube processing, each piece of film or paper receives fresh chemicals, therefore recalculation of processing time or exposure to compensate for exhaustion of the chemicals is not necessary. Tubes also reduce the exposure to chemical fumes and forces you to keep your fingers out of the chemicals. Finally, tubes make disposal of chemicals safer and easier. Anyone who has tried to empty a 16X20 tray will find a 16X20 tube a pleasure to work with.


  1. Have a ventilation system that offers:
  2. Make sure that your fan(s) can exchange the darkroom air at least every five minutes. To determine the minimum fan size needed, divide the total cubic feet of the darkroom by five (minutes). Make sure your fan is rated at this level or higher. Depending on the chemicals that are used in the darkroom, a higher level of air exchange may be more appropriate.
  3. Here are some more ventilation details.

Replace, Reduce, Reuse, Recycle, Revise:

  1. First, REPLACE any hazardous substances with non-hazardous or less hazardous substances, if available.
  2. Next, use tube processing to REDUCE the amount of chemical that you use. Do not premix chemicals; mix only what you need for one session. This assures that only fresh chemicals are used and prevents waste from aging chemicals.
  3. REUSE any chemical to exhaustion. Run tests, if appropriate, to make sure you are not throwing away usable chemicals. Use replenishers to revitalize used chemicals.
  4. After use, RECYCLE your chemicals if possible. For example, you can easily remove silver from fixer or bleach/fix and sell it.
  5. Next, REVISE the chemicals that you are about to dispose. Neutralize acids and bases. Change chemicals into other less toxic substances through chemical actions.
  6. Finally, dispose of any leftovers by diluting the chemicals with water into the sewage system. Any solvents should be safely contained for later local hazardous waste disposal.


Doing your own photographic processing is essential to obtaining the best possible results in your photographic work. Sending processing out merely shifts the health and environmental problems to another location. The chemicals will still be used. If you do the processing yourself, you can assure the best quality results, as well as the safe use and disposal of the chemicals.


If you have any ideas, suggestions or comments about these pages, please contact the Sub Club at the FRONT DESK.

To return to the main index for the Sub Club click here.

COPYRIGHT @ 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004 by Joe McGloin. All Rights Reserved.