Different embalming agents/formulations have been tried to reduce formaldehyde exposures with some reported promise but with some drawbacks in specimen preservation.  Post embalming re-profusion or injection with formaldehyde neutralizers and formaldehyde substitutes have reportedly had effects in reducing formaldehyde exposures.   Two such commercially available products are Perfect Solution® (Carolina Biological Supply, Burlington, NC.) and InfuTrace® (American Bio-Safety, Rocklin, CA).  Perfect Solution® is a proprietary tissue preservative containing alcohol and an unspecified but low formaldehyde concentration.  Infutrace is a product containing a proprietary formulation that, when applied to tissue after standard formaldehyde embalming, binds free formaldehyde by a chemical polymerization process that is undisclosed but involves as the active ingredient.  A study by Whitehead et. al. indicated that both Perfect Solution® substituted for standard formaldehyde embalming and InfuTrace® infused through the vasculature after formaldehyde embalming, resulted in  lower concentrations of formaldehyde in area, personal and tissue samples than embalming with 2% formaldehyde alone or in combination with body cavity injection of InfuTrace®.  However, Perfect Solution® reportedly yielded suboptimum fixation and a different texture, color and smell than the formaldehyde treatments .  Burkel et. al. compared  InfuTrace® to monoethanolamine and concluded that post embalming re-profusion with a monoethanolamine solution was just as effective as InfuTrace® in neutralizing formaldehyde (2.5%) and glutaraldehyde (1.08%) and cheaper, and unlike InfuTrace®, did not leave the reported  undesirable white precipitates on tissues and dissecting tables.   After monoethanolamine treatments, formaldehyde levels were reduced to below occupational exposure limits when combined with engineering controls.  Glutaraldehyde levels were not measured.  The recommended exposure limit for glutaraldehyde by ACGIH is 0.05 ppm, as a ceiling.  This is more than ten times lower than the recommended formaldehyde exposure limit by ACGIH (0.3 ppm as a ceiling).   Sleek et. al. showed significant decreases of between 42 to 84% in formaldehyde levels above InfuTrace® treated cadavers when compared with their untreated counterparts using 5% formaldehyde.   Arterial re-perfusion of formaldehyde-fixed cadavers (3.7% formaldehyde) with saturated ammonium carbonate solution by Kawamata, S., et. al. reduced formaldehyde levels both in air and in various tissue fluids.  The ammonia re-perfusion resulted in softer tissue consistency in the cadavers and greater mobility of the neck, shoulders and limbs.  However, the ammonium carbonate solution was distributed inhomogeneously in the cadaver and considerable formaldehyde remained in some tissues.  Also, after inactivation of formaldehyde, a method to suppress bacterial and fungal proliferation is necessary and this problem still needs to be resolved.  All of these studies used different formaldehyde concentrations in the embalming solutions.  Standardized embalming fluids with a lower concentration of formaldehyde has been proposed by Dixit, D. as a means of controlling exposures.  Coleman R., et. al. used a low formaldehyde (0.5- 0.75%), high salt (sodium chloride) embalming solution and long-term storage before dissection (3 months to a year), along with local exhaust to control formaldehyde exposures to below even the most stringent exposure limits.  The preservative was inexpensive and resulted in minimal structural distortion or shrinkage, supple tissue which was easy to dissect, tissues that retained much of their natural color with no "browning oxidation effects and no fungal growth.  The high salt content prevented any further significant desiccation but there was some minor salt deposits on the skin or internal organs.  So far, alternative embalming agents/formulations for formaldehyde exposure control is an approach which may have promise but it is still very experimental. 

We looked into the possibility of plasticizers, which leaves the cadaver's blood vessels nicely color-coded for teaching purposes, but the prep work is extremely dangerous and the prep room would have cost a fortune in controls. I believe Queen's University was and may be still using this technique.

We've been using Infutrace for over a decade, mostly in animal anatomy. We haven't had any problems to report but the users aren't crazy about it due to the fact it doubles up the preservation prep work.  This is because it is a formalin replacement solution, not a substitute, so you still have to do a formalin-based perfusion, but then after the specimen is fixed you have to repeat the process to purge out all the formalin-based embalming solution.  Despite our best efforts we haven't been able to find out the exact ingredients because they have all been in exempted quantities under our Hazardous Products Act. In other words there are no hazardous ingredients, at least not above the thresholds specified in the Act i.e. 1% if the ingredient is a carcinogen and 0.1% if it has other toxic effects.   

From our discussions with the supplier we believe the Infutrace is a blend of buffer solution(s) mixed with some sort of polymer resin. While this is clearly not enough info to do one's own risk assessment we were comfortable in concluding that it has to be safer than the phenol-methanol-formaldehyde triumvirate used in classic embalming fluid.

Monona cites some really good examples of situations where products like PCB's and Halons of known toxicity were replaced by compounds of unknown (untested) toxicity, with disastrous results.  Another classic one is the replacement of degreasers over the years, starting with carbon tetrachloride, then methylene chloride, then TCE, then PERC, but all of those substitutions had one thing in common - they were merely replacing the offending compound with their evil cousins (similar compounds).  Great lessons learned.  I don't think we're making the same mistake with our choice of Infutrace but Monona is right (as always!) to say that you should always conduct your risk assessment before choosing a substitute.

W.

From: DCHAS-L Discussion List [mailto:dchas-l**At_Symbol_Here**MED.CORNELL.EDU]On Behalf Of Monona Rossol
Sent: Monday, August 25, 2014 11:30 AM
To: DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU
Subject: Re: [DCHAS-L] Cadaver labs and formaldehyde

See replies to john Nail's questions below:

>A question for those of you who have cadaver labs -

>Does a 'formaldehyde-free' embalming method for lab cadavers exist?

Yes, but it is not a simple perfusion and involves the full immersion of the 

cadaver in a tank. 

Alternatively you can still embalm with formalin-based fluids but then you can 

replace them with Infutrace or plasticizer so that the cadavers have little or 

no HCHO in them when they are brought into the student lab.  

>If a university is building a cadaver lab, does the lab need to have 

specialized equipment that will remove airborne formaldehyde?

If you have cadavers preserved in formalin you need a local exhaust system (e.g. 

downdraft dissection tables) to protect the students and instructors from 

exposure.  The area where you prep the cadavers should have a top quality local 

exhaust system as the technicians who do this work are there for the long term 

and are at greatest risk of exposure.

>Can the air in the lab be vented to outside the building without treatment? 

It depends on the concentration coming out the stack and what your local 

authorizes will allow but in my experience there will be so much air flowing 

through your exhaust system that the resultant effluent concentration may very 

well be below regulated levels.  

>Is there a legal (compliance or civil) reason to be monitoring for 

formaldehyde?

In my jurisdiction we have to monitor annually, due to the fact HCHO has made 

its way onto the carcinogen list. As well, due diligence dictates that you need 

to have good monitoring data if ever you are challenged with any lawsuits.  True 

story: in our case the availability of reliable exposure data saved us millions 

of dollars. 

W. 

>Many thanks for your replies,

>John Nail

>Professor of Chemistry

>Oklahoma City University

Wayne Wood, CIH | Associate Director, University Safety (EHS), University 

Services - Directeur Adjoint, Direction de la pre´vention (SSE), Services 

universitaires | McGill University | 3610 rue McTavish Street, 4th floor | 

Montreal, Quebec, Canada, H3A 1Y2 | Tel: (514) 398-2391