University of Turin study in Italy shows under-vacuum sealing systems reduce exposure to formaldehyde by 75% among nurses handling tissue biopsy specimens during surgery
Histology technicians and anatomic pathology (AP) laboratories regularly handle dangerous chemicals such as formaldehyde. They understand the risks exposure brings and take precautions to minimize those risks. However, in operating suites worldwide, nurses assisting surgeons also are being exposed to this nasty chemical.
Nurses must place biopsies and other tissues into buckets of formaldehyde to preserve the tissue between the operating room (OR) and histology laboratory. Formaldehyde, along with toluene, and xylene, is used to process and preserve biopsy tissue, displace water, and to create glass slides. It is an important substance that has long been used to maintain the viability of tissue specimens. Thus, exposure to formaldehyde among nurses is well-documented.
According to a National Academy of Sciences report, formalin, a tissue preservative that is a form of formaldehyde, has been linked to:
· Nasopharyngeal cancer; and,
However, as Dark Daily previously reported, “One alternative to storing specimens in buckets with formalin is to vacuum-seal specimens … [so] that both the quality management of the patient specimen and worker safety for handling the specimens are greatly improved.” (See Dark Daily, “Anatomic Pathology Labs Adopt New Ways to Package, Transport, and Store Specimens to Reduce Formalin and Improve Staff Safety in Operating Theaters and Histology Laboratories,” October 13, 2014.)
Now, motivated by increasing formaldehyde regulations in Europe, as well as the need to increase awareness of exposure risks, the University of Turin (Unito), and other hospitals in Italy’s Piedmont region, conducted a cross-sectional study of 94 female nurses who were being potentially exposed to formaldehyde.
Researchers Aim for “Formalin-Free” Hospitals
The Unito study showed that nurses using an under-vacuum sealing (UVS) system in ORs are exposed to levels of formaldehyde 75% lower than those who did not use the system. This study differs from other similar tests because the level of exposure is not just potential, due to environmental contamination, but confirmed with analytic data from specific urine analyses.
The researchers divided the nurses into two groups:
· One group immersed samples in containers of formaldehyde following standard procedures;
· The other group worked in operating rooms equipped with a UVS system.
The researchers described a UVS system that called for the tissue removed during surgery to be sealed in a medical grade vacuum bag and refrigerated at four degrees centigrade before being transferred to the lab for fixation.
One example of a UVS system is TissueSAFE plus, developed by Milestone Medical, located in Bergamo, Italy, and Kalamazoo, Mich. According to the company’s website, the system, “Eliminates formalin in the operating theatre and allows a controlled formalin-free transfer of biospecimens to the laboratory.”
The image above is from a research paper by Richard J. Zarbo, MD, Pathology and Laboratory Medicine, Henry Ford Health System. It describes “five validation trials of new vacuum sealing technologies that change the approach to the preanalytic ‘front end’ of specimen transport, handling, and processing, and illustrate their adaptation and integration into existing Lean laboratory operations with reduction in formalin use and personnel exposure to this toxic and potentially carcinogenic fixative.” (Image copyright: Henry Ford Health System/Springer International Publishing.)
Increased Scrutiny Leads to New Pathology Guidelines
In a paper published in Toxicology Research, a journal of The Royal Society of Chemistry, the researchers noted a marked difference related to the adoption of the under-vacuum sealing procedure, as an alternative to formaldehyde for preserving tissues. “Nurses, operating in surgical theatres, are traditionally exposed to formaldehyde because of the common and traditional practice of immersing surgical samples, of a size ranging between two and 30 centimeters, in this preservative liquid (three to five liters at a time) to be later transferred to a [histopathology] lab,” the authors wrote. “We evaluated the conditions favoring the risk of exposure to this toxic reagent and the effect of measures to prevent it.”
Throughout Europe, increased scrutiny has forced medical pathology associations to write new guidelines that accept alternative methods to formaldehyde-based tissue preservation methods.
“In Europe, and in Italy in particular, the level of attention to formaldehyde exposure in the public health hospital system has become very high, forcing pathology associations to rewrite guidelines,” Marco Bellini, General Manager of the Medical Division at Milestone Medical, told Dark Daily. “What makes this study unique from many other similar tests is that the level of exposure has been confirmed with data from specific urine analyses,” he added.
The Italian Society of Pathological Anatomy and Diagnostic Cytology (SIAPEC), a division of the International Academy of Pathology, wrote general guidelines for AP labs that have been accepted and officially published by the Italian Ministry of Health.
The main topic of these guidelines is the preanalytical aspects of specimen collection, transportation, and preservation, where the vacuum method has been indicated as a valid alternative to improve the standardization of these crucial steps in pathology. By moving the starting point for specimen fixation from the OR to the histology labs, parameters can be controlled and documented, with the main advantage of reducing formaldehyde exposure by operators at the collection point.
These guidelines will be presented at the European Society of Pathology (ESP) with the intent to extending them throughout Europe.
Toluene’s and Xylene’s Effects Studied
Formaldehyde is not the only potentially harmful substance in the clinical laboratory. As previously noted, common solvents toluene and xylene also are potentially hazardous.
In fact, a study of pathologists, lab technicians, and scientists who work with toluene and xylene published in the Journal of Rheumatology found that the chance of acquiring Raynaud Syndrome (a vascular condition) doubled for those workers. (See Dark Daily, “Health of Pathology Laboratory Technicians at Risk from Common Solvents like Xylene and Toluene,” July 5, 2011.)
Medical laboratory leaders are reminded to initiate processes that ensure safe specimen handling, transport, and processing, as well as workflow changes that eliminate chemical odors in the lab. Studies, such as those cited above, may provide information necessary to affect change.
—Donna Marie Pocius
Related Information:
Histologic Validation of Vacuum Sealed, Formalin-Free Tissue Preservation, and Transport System
Notes Regarding the Use of Formalin, Reclassified as “Carcinogenic”
Health of Pathology and Laboratory Technicians at Risk from Common Solvents Like Xylene and Toluene
