Chris how old are your specimens? Are they "historic" or more recent? Historic specimens tend to be in a 10% formalin preservative you can purchase from many different suppliers or make your own. You can do a simple spot plate test for aldehydes but it won't tell you a %, there are some dip-sticks tests out there that do ppm or ppb (don't remember which).
Depending on the type of specimens you may want to actually move away from a 10% formalin into a 70-75% ethanol preservative since formalin has been shown to be a carcinogen in test animals as well as being flammable. A 75% solution of ethanol is still flammable, however, carcinogenicity is removed from the equation. Long term storage in ethanol is more recommended than formalin because there is less degradation to the bones and tissues due to acidity. However some specimens, such as larva or some soft-bodied invertebrates, don't fare as well in the alcohol . The majority of specimens seem to last longer, with fewer distortions (and without the carcinogenicity) in alcohol. I have a procedure for converting from formalin to alcohol if you are interested (you can't just dump out the formalin and drop them into 70% alcohol…you have to do it in stepwise increasing % increments). You also can't just get rid of the formalin (which I'm sure you know), you would have to arranged for waste pick-up.
I could be wrong here, so please anyone who knows better, speak up!
Hope this helps.
Chemical Hygiene Officer, Chemistry Lab Coordinator &
Lecturer CHS 319
West Virginia Wesleyan College
59 College Ave
Buckhannon, WV 26201
Seems like I heard of something like this years ago but cannot find any references today.
Does anyone know of any manuals or guidelines on how to refill biological specimens with preservatives especially if the preservative is unknown?
I'm interested in quick methods of determining what the preservative is without using odor of course (formalin, paraformaldehyde, ethanol, etc.) and techniques for refilling.
Christopher E. Kohler
Certified Chemical Hygiene Officer
Laboratory Safety Manager
Office of Environmental, Health, and Safety Management
1514 East Third Street
Bloomington, IN 47405
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