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Environmental Performance of Xylene, Hydrochloric Acid and Ammonia Solution During Pap Stain for Diagnosing Cervical
Jeel J Moya-Salazar1, Victor A Rojas-Zumaran1
1Hospital Nacional Docente Madre Niño San Bartolome, Lima, Lima Peru.
Background:
Little importance has been placed on sustainability of the Papanicolaou (Pap) stain, the gold standard for the diagnosis of cervical cancer, for global environmental health. The standard Pap stain uses environmentally toxic and carcinogenic reactants such as xylene, hydrochloric acid and ammonia solution.
Objectives:
To eradicate the use of environmentally toxic and carcinogenic reactants through the validation of the Ecologic Papanicolaou (Eco-Pap) test.
Methods:
Reagent handling strategies were divided in three phases: used Harris' progressive hematoxilin, polychromatic solution and direct mounting that were analyzed by PEED-Cytology, Staining Quality Index (ICT) and the Bethesda system 2014.
Results:
A total of 52,319 Pap smears stained with Eco-Pap were admitted (ICT=0.91). Validation of the Eco-Pap versus conventional staining was optimal (Kappa =0.89) and the sensitivity and specificity of the method were 57% and 98%, respectively. Eco-Pap reduced the environmental contamination produced by xylene (66 liters), hydrochloric acid and ammonia (5.5 liters each) over nine months, and all diagnoses coincided with the cytological details.
Conclusions:
The Eco-Pap is an innovative method that transforms Pap testing into a sustainable and supportable technology.
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