Wet Specimen Disposal in the Surgical Pathology Laboratory

This post is a continuation of the reply to a visitor’s letter (see the comment to the article Realm in the Perspectives in Grossing Technology section and my reply to the comment). For some reasons, the specimen and formalin disposal subject was limited to two sentences in my article A Pragmatic Approach to Formalin Safety in Anatomical Pathology. LabMedicine 2009 Vol. 40 (12):740-746. It is time to bring up this question at the Grossing Technology and Beyond blog.

Every institution has its own protocol for keeping wet specimens as well as a particular schedule and mode of disposal. Most laboratories keep it on the active shelf for a month, some for three month-the time period that is sufficient for diagnosis, however, in some cases, it is requested that the specimen be kept on a prolonged or permanent basis. Incidentally, in autopsies, the material is usually kept at least for a year, unless a longer term is specified. Shelves do not need special hood/fan ventilation. Specimens do not generate formaldehyde vapors if the container is properly closed. The exposure occurs only during manipulation

There are two options for disposal: in the laboratory or outside it (in the morgue, special room, etc.). Large laboratories prefer the latter option.

Safety concerns are evident in the following three aspects of wet specimen disposal: 1. Separation of the specimen from fixative, in most cases formalin; 2. Formalin neutralization with or without recycling; 3. Specimen storage and disposal. This post will discuss only the first aspect, as an extended response to the comment.  Both formalin handling and specimen storage will be presented in separate articles: first in the Safety section, the second in Perspectives in Grossing Technology section.

Separation of the specimen from formalin is a common practice because most disposal companies request this. Separating of the specimen from the fixative is potentially the most significant encounter with formalin as far as safety is concerned. Formaldehyde’s harmful effect occurs due to a high concentration of evaporating formalin, when formaldehyde saturates the laboratory environment and is in close proximity to the breathing area of the worker.

If formalin /formaldehyde’s carcinogenicity is not beyond a reasonable doubt, quite the opposite, and its harmfulness on general heath has also has not been proven (this issues require separate discussion), its local damaging effect is indisputable. Formalin works as local fixative, that eliminates the first line of defense in infection exposure, creates allergies, and generates chronic irritation of the upper respiratory tract, especially nasopharygeal area.   During specimen disposal the individual is vulnerable, but this often goes unnoticed and slips between OSHA regulations because nobody does any measurements at time except on rare occasions as by the author of the comment on my articles and the post on this subject.

Let me quote from his letter.

It’s interesting also that no other lab/hospital in the large metro area is worried about this “bolus” exposure. My belief is their IH monitoring has not been granular enough to monitor tasks … they might simply be putting on a passive dosimeter for 8-hrs and call that good

He is exactly right.

Unfortunately, the standard management approach to monitoring would not work either, even if the monitoring measurement were done. The ACGIH exposure limit is not achievable in most real- life situations, but an OSHA TWA STEL of 2 ppm is not appropriate because 15 minute test cannot be applied to prolonged work when the cumulative effect of formaldehyde exposure starts. Furthermore, the ACGIH’s irritation limit is also not useful because the accommodation is accomplished due to fixation (really) of the receptors of the upper respiratory tract, especially the nasopharyngeal area. Respirators are not a solution, but standard PPE accompanied by enhanced ventilation of a modified grossing station can make a difference.

Besides absolutely obligatory OSHA requirement of PPE (protective gown, apron, safety glasses , and a mask), the procedure requires a large table space, corrosion resistant metallic surface, easy availability of water/sink/drain, permanently running water to increase humidity, and more intensive than at the regular grossing station ventilation. A separate special room is definitely desirable. It’s not enough to make a ventilation hood for specimen disposal. There should be a comprehensive approach that, of course, includes local ventilation.

Similar requirements are involved in grossing bones such as large firm corrosive resistant table, enhanced ventilation, and a separate place in the grossing room.

Bone specimens arrive at the surgical pathology laboratory periodically; they are not “rush” specimens and can be combined together for processing, especially keeping in mind the more strict requirements of PPE.

The TBJ Inc. company manufactures a specialized Bone Grossing Table (BGT) www.tbjinc.com/Product.aspx?id=110401. For full disclosure, I participated in the development of the table.

Large and even middle size laboratories, in my view, should have a bone grossing/specimen disposal station, preferably located in a separate room. New build or remodeled laboratories should include such a complex in the project. Pathology departments of large hospitals, especially in academic institutions have autopsy divisions that need to disposal of postmortem materials. Brain washing (literally) should also be done after prolonged formalin fixation. The Bone Grossing/ Specimen Disposal stations can be a solution for an effective and safe work place, killing two, perhaps, three, birds with one stone.

Again, this post is only a part of the comprehensive approach to the specimen disposal. See also the article Specimen Storage in the Surgical Pathology Laboratory in the section Perspectives in Grossing Technology.

 

 

 

Bookmark the permalink.

Leave a Reply

Your email address will not be published. Required fields are marked *