Comparative Evaluation of Refined Palm Oil as a Non-Toxic Alternative to Xylene for Histological Tissue Processing: A Cross-Sectional Study

Abstract

Introduction: Xylene, commonly used as a clearing agent in histological tissue processing, poses toxic and environmental risks. This study explores refined palm oil as a safer, eco-friendly alternative, evaluating its performance in nuclear staining, cytoplasmic staining, clarity of staining, and tissue distortion.

Objectives: The objective of the study was to compare the clearing efficiency of refined palm oil with xylene in histological tissue processing.

Methods: A cross-sectional study was conducted with 20 archival human oral soft tissue specimens fixed in 10% neutral buffered formalin. Tissue specimens were processed using xylene (Group A) and refined palm oil (Group B), followed by haematoxylin and eosin staining. Two oral pathologists performed microscopic evaluations to assess nuclear staining, cytoplasmic staining, clarity of staining, and tissue distortion. Statistical analysis was conducted using the Chi-square test and Cohen’s Kappa for inter-observer agreement.

Results: Both xylene and refined palm oil yielded identical results for nuclear staining and no tissue distortion. For cytoplasmic staining, 80% of the refined palm oil group showed excellent results, compared to 70% in the xylene group. Clarity of staining was excellent in 80% of specimens for both groups. Statistical analysis showed no significant differences (p > 0.05) between the two clearing agents for any evaluated parameter.

Conclusions: Refined palm oil is as effective as xylene in histological tissue processing, offering comparable staining quality and tissue preservation. Its low cost, availability, non-toxicity, and eco-friendly characteristics make it a valuable alternative, especially in settings aiming to reduce occupational and environmental risks.