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Re: [ARSCLIST] mold questions

Hi Trey:

The mold issue is an important one. Do take proper and safe care in handling the tapes. Your posting is missing some important information, which, if known, would help in a better response. If you list the make and model of tape, its age, how long in its present storage condition, etc., that information helps. Mold and fungus is a major biological/chemical deterioration mechanism which typically breaks down dead, or nearly dead, organic matter into its final phases of decomposition for eventual reprocessing in the larger biological life cycle. Almost any and all organic carbon based material in the presence of moisture can develop mold or fungus issues. Tapes and most all recording media is made using organic chemicals and plastics of various kinds. Thus the extreme importance for any organic media for proper storage conditions with relatively low humidity and normal moderate storage temperatures to either prevent mold and fungus from occurring in the first place, or to slow it down as much as possible. High humidity and/or high temperature of any type or kind makes everything worse by accelerating unwanted chemical activity. The biggest offender for tape mold and fungus issues are those tapes made with a carbon black back coating. The chemically weak carbon black back coating in poor storage environments quickly and badly deteriorates in a progressive fashion, usually within a few years of the tape's manufacture. It also chemically attacks the rest of the tape. However, the other tape chemicals of the base film and oxide coating do last a lot longer and they can be fairly, but not perfectly, resistant to these moisture problems for a long time provided the oxide is correctly cleaned up and the carbon black back coating is removed and disposed of. In its deteriorated condition, the degraded carbon black back coating provides a substantial seed bed for moisture attraction, retention, and the production of other chemicals resulting in the rapid growth of mold and fungus along with many other major tape problems. These chemical facts are readily apparent to anyone who does chemical and biological laboratory research studies of the tape's total chemistry and its various interrelated problems. I do have eye opening highly magnified pictures of these tape deterioration facts and activities. They are included in a paper I wrote in conjunction with many first rate forensic chemists who completely analyzed the tape's chemical issues and who then wrote up many superb scientific chemical reports on the tape deterioration matters. But there is a communication difficulty because the lab work is very technical. The lab reports go on for hundreds of pages written up in chemical jargon terminology. This cannot be readily or correctly boiled down to either sound bites or plain English without falsifying, by oversimplification, this high level detailed scientific information. Thus these definitive chemical reports are not easily communicated, known or correctly understood by lay persons who do not have a scientific and chemical background.

I discovered and proved in the chemical lab that by a new, proper, and sophisticated cleaning of both tape surfaces, one can get rid of the moisture seed bed, mold, fungus, and other tape problems, thereby restoring the tape in a highly effective and safe manner. Most important of all, when the tapes are properly handled, their overt behavioral response is highly positive with superb performance in every department. Unfortunately, it is too a long story for this short reply. Perhaps someday, your tapes can be restored with the new better methods, provided the mold and fungus has not advanced too far in their bacterial attack upon your tapes.

You mentioned a "water leak" but do not say if this water leak is from tap water, rain water, or ground water. Tap water usually has Chlorine in it which kills many kinds of bacterial and
other bad substances. Rain water (or distilled water) does not have Chlorine in it, so mold and fungus can thus grow more rapidly in it if a tape gets wet from rain or pure distilled water. Worse still is ground or waste water which does not have Chlorine and has even more debris and other unwanted chemical stuff in it. So the kind of water and what is in the water or not is very important.

I am very concerned about your personal safety in handling these tapes as some kinds of mold and fungus are a deadly poison. Be sure to wear a mask, rubber gloves, and take other precautions. Also if the mold or fungus gets loose in a state of spore reproduction, it can spread to other places, tapes , etc and infect them, causing major infestation problems. If you really want to know, go to a biologist, get him to take a sample, grow a culture, do tests, and find out exactly what it is. Maybe you are safe and OK, but maybe not. One should check things out in the lab rather than just make guesses. Also mold and fungus can go into a dormant state for a time and then have a spore explosion if it gets the water or moisture it needs for its reproduction purposes. The material you are dealing with may be harmless and actually dead or it could be just in a dormant state that is potentially dangerous.

The microscope needed for a good look at your tapes requires considerable magnification horsepower. When carefully used by a scientifically educated, trained, experienced, knowing mind with a sharp eye for details then one will fully and correctly understand all that is going on. As for magnification, special viewing techniques are needed along with a microscope of at least 800 power to start really seeing anything of importance. If you want to get down to the molecular, atomic, or cell level, use 10,000 times magnification. If you go higher to 20,000 times magnification, it really gets exciting by going way down to the nitty gritty. The extraordinary universe of extremely small chemical realities is most interesting and vitally important. The chemical consequences of very small things are huge for nearly everything. Its shocking as well as depressing that chemistry is largely ignored, misunderstood, or badly distorted these days, especially by self appointed "experts" with made up theories and blind beliefs in wrong dogmatic views that do not have a factual or scientific leg to stand on. Much of it is just mere words. If one wants chemical and scientific facts, truth, and genuine comprehension, one has to be both able and willing to dig deep for it over time. Carefully read the relevant chemical lab reports on tape issues with focused concentration and strict attention to all details. Use critical thinking skills and scientific methods to develop a full clear systematic scientific laboratory understanding of all that is there. It is extremely hard, slow, demanding and painstaking work to do this, but it is the only way to go if one wants knowledge instead of an endless parade of mere mistaken opinions that are not up to par.

Good luck in safely fixing your tapes.

Charlie Richardson

On Jan 29, 2009, at 12:58 PM, Trey Bunn wrote:

I'm currently going through several boxes of reel to reel tapes (some
acetate, some polyester) that may have been exposed to mold.  There
was a water leak where they were stored, and some of the boxes got
slightly wet, so we're checking them to see if they're okay or not.
So far, I've only seen mold on one of the boxes (the tape box, that
is, not the larger cardboard box holding all of the tapes), and some
of that got onto the outer layer of tape.  The other tapes appear to
be somewhat dirty and poorly packed in some cases, but as far as I can
tell, no mold.  I've been using a small brush to gently dust off what
I've been finding, and my assumption is that if it brushes off easily,
it's just dust, and mold would adhere more stubbornly.

Am I right about this?  It's been a couple of years since I've seen
truly moldy tapes, so I want to make sure I'm not overlooking
something.  If I look at these under a microscope, what magnification
do I need to use in order to see actual spores (if they're there)?
It's a little difficult going through these because it's apparent that
prior to two or three years ago, these tapes were not stored in ideal
conditions.  (Which of course means they might have mold on them from
years ago and not this recent water incident.)

--------- Trey Bunn Audiovisual Conservator Emory University Libraries Preservation Office Atlanta, GA 404-727-4894

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