Advancing green chemistry in histopathology: A comparative study of coconut oil and turpentine oil as deparaffinizing agents.

INTRODUCTION: Precise microscopic examination is highly dependent on the quality of tissue processing. A number of chemicals such as formaldehyde, xylene, ethanol, and various stains are utilized in diverse stages of routine tissue processing. Of these, xylene causes potential health hazards. Studies on biosafe substitutes for xylene were experimentally evaluated to be effective only at temperatures well above the temperatures used in routine histopathology, which renders brittleness and loss of antigenicity to tissue specimens. The present study aimed to compare the efficacy of coconut oil and turpentine oil as deparaffinizing agents at temperatures used in routine histopathology procedures.

MATERIALS AND METHODS: Three hundred sections from 100 paraffin-embedded tissue blocks were obtained from the archives of the department. One section from each tissue block was deparaffinized in xylene, coconut oil, and turpentine oil and stained using the conventional hematoxylin and eosin staining method. The stained sections were coded and randomly analyzed using a scoring system to enable the comparison between the different deparaffinizing methods.

RESULTS: Results showed that the sections deparaffinized using turpentine oil showed adequate staining for diagnosis, and the quality of staining was at par with that of xylene. Coconut oil showed 79% adequacy of staining when used for deparaffinization. Sections deparaffinized in turpentine oil and coconut oil were adequate for diagnosis.

CONCLUSION: Coconut oil and turpentine oil are effective alternatives to xylene in deparaffinization at temperatures used in routine histopathology, thus providing a fresh scope for green chemistry in histopathology laboratory.