Coping with formalin banning in pathology: under vacuum long-term tissue storage with no added formalin
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Formalin is toxic and has recently been classified as carcinogenic leading to a proposed European formalin ban. But, the pathology use of formalin has however been completely overlooked, and this is proving to be a relevant issue, as no alternative, reliable, tissue fixative is available. Various systems have been proposed to reduce formalin use and exposure; long-term storage and disposal of formalin is also a problem. With this in mind, under vacuum sealing (UVS) systems have been proposed for transportation/storage, however, for how long tissue retains its characteristics (morphological and molecular) is unknown. This study aims to compare histology specimens stored by formalin immersion (FI) and specimens stored after fixation with UVS technique with no additional formalin, at different time periods. Twenty tissue samples (10FI; 10UVS) were stored for different time periods (15 days, 1–2–3–6–12 months) for a total of 120 samples, compared with regard to their morphology, histochemistry, immunoreactivity (24 specific antibodies) and DNA status. All samples showed well-preserved morphology and overlapping staining quality. A significant reduction in immunoreactivity was however identified in the various time periods, particularly for heat pre-treated nuclear antigens, and this commenced earlier (1 month) for FI. UVS storage showed higher DNA content than FI but slightly poorer DNA integrity. These results add important knowledge to the use of UVS in daily practice, as long-term storage of pre-fixed tissue in UVS is not detrimental to the quality of tissue while having the boon of using very little formalin with less operator exposure and lower disposal costs.
KeywordsFormalin ban Vacuum storage Safety Pathology
We wish to thank all of the technical staff at the Anatomic Pathology laboratory, IRCCS Policlinico San Martino, Genoa, Italy and Mrs Sonia Massa for her contribution to the Quality Assurance Program.
Compliance with ethical standards
Conflict of interest
No conflict to disclose.
- Baan R, Grosse Y, Straif K, Secretan B, El Ghissassi F, Bouvard V, Benbrahim-Tallaa L, Guha N, Freeman C, Galichet L, Cogliano V, WHO International Agency for Research on Cancer Monograph Working Group (2009) A review of human carcinogens—part F: chemical agents and related occupations. Lancet Oncol 10:1143–1144. https://doi.org/10.1016/S1470-2045(09)70358-4 CrossRefPubMedGoogle Scholar
- European Parliament and Council of European Union (2008) Regulation (EC) No 1272/2008 on classification, labelling and packaging of substances and mixtures, amending and repealing Directives 67/548/EEC and 1999/45/EC, and amending Regulation (EC) No 1907/2006. Off J Eur Union L 353:1–1355Google Scholar
- IARC Working Group on the Evaluation of Carcinogenic Risk to Humans (2006) Formaldehyde, 2-butoxyethanol and 1-tert-butoxypropan-2-ol IARC monographs on the evaluation of carcinogenic risks to humans, vol 88. International Agency for Research on Cancer, LyonGoogle Scholar
- Kiernan JA (2008) Theory and practice. Histological and histochemical methods. Scion Publishing, Bloxham, pp 12–44, 431–437Google Scholar
- Richter KN, Revelo NH, Seitz KJ, Helm MS, Sarkar D, Saleeb RS, D’Este E, Eberle J, Wagner E, Vogl C, Lazaro DF, Richter F, Coy-Vergara J, Coceano G, Boyden ES, Duncan RR, Hell SW, Lauterbach MA, Lehnart SE, Moser T, Outeiro TF, Rehling P, Schwappach B, Testa I, Zapiec B, Rizzoli SO (2018) Glyoxal as an alternative fixative to formaldehyde in immunostaining and super-resolution microscopy. EMBO J 37(1):139–159. https://doi.org/10.15252/embj.201695709 CrossRefPubMedGoogle Scholar
- Shi SR, Liu C, Taylor CR (2007) Standardization of immunohistochemistry for formalin-fixed, paraffin-embedded tissue sections based on the antigen-retrieval technique: from experiments to hypothesis. J Histochem Cytochem 55:105–109. https://doi.org/10.1369/jhc.6P7080.2006 CrossRefPubMedGoogle Scholar
- Veneroni S, Dugo M, Daidone MG, Iorio E, Valeri B, Pinciroli P, De Bortoli M, Marchesi E, Miodini P, Taverna E, Ricci A, Canevari S, Pelosi G, Bongarzone I (2016) Applicability of under vacuum fresh tissue sealing and cooling to omics analysis of tumor tissues. Biopreserv Biobank 14:480–490. https://doi.org/10.1089/bio.2015.0093 CrossRefPubMedGoogle Scholar
- Vincek V, Nassiri M, Nadji M, Morales AR (2003) A tissue fixative that protects macromolecules (DNA, RNA, and protein) and histomorphology in clinical samples. Lab Investig 83:1427–1435. https://doi.org/10.1097/01.LAB.0000090154.55436.D1 CrossRefPubMedGoogle Scholar
- Zanini C, Gerbaudo E, Ercole E, Vendramin A, Forni M (2012) Evaluation of two commercial and three home-made fixatives for the substitution of formalin: a formaldehyde–free laboratory is possible. Environ Health 11:59. https://doi.org/10.1186/1476-069X-11-59 CrossRefPubMedPubMedCentralGoogle Scholar