Thanks to the Histonetters who responded to my question about
long-term storage QC of tape coverslippers. Many responded
off-line while others responded via Histonet.

I also went to the Histonet archives and looked around
about this problem before.

With all of this information, I was able to type up a
1 1/2 page report for the histology supervisor, who will
be sharing the information with the pathologist who
originally asked for this information.

The following is a brief summary for histonetters. 

AGE:

The first model seems to have been demonstrated at
NSH Symposium in about 1984 (16 years ago).

Several people reported that their machines were
9-12 years old. They reported no problems with their
tape coverslippers. Old slides are still fine.


PROBLEM:

Some people have reported problems. I seemed to
discern 3 trends.

A. Insufficient xylene flow during coverslipping.

Usually the tape starts peeling/popping off within
a few hours to days. This was easily corrected by
adjusting the xylene flow.

B. Poor Tape Quality

People commented on the quality of tapes sold by
different companies. Some brands worked for some 
labs, different brands worked better for other labs.

There have also been changes in the formulations
of the tapes within companies. Some people reported
problems with some formulations.

Once people found a brand and formulation that they
liked, they have not had any curling/peeling problems.

Usually problems were seen within a few days to
weeks, possibly up to a year.

C. Humidity

This seems to be the BIG problem and may be the cause of
many of the problems people have been reporting. In general, 
those labs from more humid regions (Texas, Florida, etc.)
seemed to report more peeling incidents than those
areas from drier regions. Not always, but there did
seem to be a trend.

According to some people, the companies send a
statement with the tapes, stating that the tape
and slides need to be stored in an area of low
humidity. Those labs with high humidity (or who
experienced a flood in the lab) had curling of
the tape coverslip.

This seemed to occur from 3-5 years after 
originally coverslipped. Some reported some slides
had curling, others reported 50% of the slides, 
some stated all slides.


RECOMMENDATIONS:

Make sure there is sufficient xylene flow during
coverslipping.

If having problems, try out different brands, since 
your humidity and storage conditions may require a 
different tape formulation.

Check on the humidity level of all your slide storage 
areas. Keep it low, at or below the percent recommended 
by the company that sells you the brand of tape you use.


Again, thanks to Histonetters for all your help.

Peggy A. Wenk, HTL(ASCP)
William Beaumont Hospital
Royal Oak, MI 48073