title: Bio-Friendly Alternatives for Xylene - Carrot oil, Olive oil, Pine oil, Rose oil.
abstract: BACKGROUND
  Xylene is a flammable liquid with characteristic petroleum or aromatic odours, it is miscible with most of the organic solvents and paraffin wax. Xylene clears tissues rapidly and renders transparency, facilitating clearing endpoint determination, this made it to be used as a clearing agent in routine histopathological techniques. Even though it is a good clearing agent, it causes damage to the tissues by its hardening effect particularly those fixed in non-protein coagulant fixatives. Apart from these tissue effects, it has severe, long lasting ill effects on health of technicians and pathologists when exposed to longer duration. Hence in order to overcome these effects and replace xylene with a safe alternative agent, the present study was carried out to assess the clearing ability and bio-friendly nature of four different natural oils i.e., Carrot oil, Olive oil, Pine oil and Rose oil in comparison with that of Xylene. According to Bernoulli's principle of fluid dynamics, to decrease viscosity of these oils and increase penetration into tissues for rapid clearing hot-air oven technique was used.
  
  
  OBJECTIVE
  To assess:1) Clearing ability and bio-friendly nature of four different oils i.e., Carrot oil, Olive oil, Pine oil, Rose oil in comparison with that of xylene, 2) Application of Bernoulli's principle of fluid dynamics in rapid clearing of tissues by using hot-air oven.
  
  
  METHODS
  Forty different formalin fixed tissue samples were taken. Each sample of tissue was cut into 5 bits (40x5=200 total bits) which were subjected for dehydration in differential alcohol gradients. Later, each bit is kept in 4 different oils such as Carrot oil, Olive oil, Pine oil, Rose oil and xylene and transferred into hot-air oven. Further routine steps of processing, sectioning and staining were done. Individual sections cleared in four different oils were assessed for cellular architecture, staining quality and a comparison was done between them.
  
  
  RESULTS
  Results showed that all the four oils had ability to clear the tissues similar to that of xylene. Pine oil was superior in its physical and clearing properties, which also maintained good cellular architecture and distinct staining quality, when compared with other oils and xylene.
  
  
  CONCLUSIONS
  Carrot oil, Olive oil, Pine oil, Rose oil, are not only bio friendly and economical but can also be used as clearing agent instead of xylene. In this study stability and longetivity of haematoxyllin and eosin staining was evaluated for over a period of one year and no significant difference in staining quality were observed.
authors.affiliation: Post-Graduate Student, Department of Oral & Maxillofacial Pathology, Kamineni Institute of Dental Sciences , Nalgonda, Telangana, India .
authors.forename: Sugunakar Raju Godishala
authors.initials: SR
authors.lastname: Swamy
authors.affiliation: Professor and Head of the department, Department of Oral & Maxillofacial Pathology, Kamineni Institute of Dental Sciences , Nalgonda, Telangana, India .
authors.forename: Surapaneni Rateesh Kumar
authors.initials: SR
authors.lastname: Nandan
authors.affiliation: Reader, Department of Oral & Maxillofacial Pathology, Kamineni Institute of Dental Sciences , Nalgonda, Telangana, India .
authors.forename: Pavan G
authors.initials: PG
authors.lastname: Kulkarni
authors.affiliation: Reader, Department of Oral & Maxillofacial Pathology, Lenora Institute of Dental Sciences , Andhra Pradesh, India .
authors.forename: Thokala Madhusudan
authors.initials: TM
authors.lastname: Rao
authors.affiliation: Post-Graduate student, Department of Oral & Maxillofacial Pathology, Kamineni Institute of Dental Sciences , Nalgonda, Telangana, India .
authors.forename: Pavan
authors.initials: P
authors.lastname: Palakurthy
keywords: Bernoulli’s principle; Clearing agent; Histopathology; Hot-air oven