title: Analysis of chain saw lubricating oils commonly used in Thailand's southern border provinces for forensic science purpose.
abstract: In recent years, Thailand's southern border provinces (Malay-Muslim-majority border provinces) have become the scene of violence and insurgency. One of the attack patterns is the blocking of roads with perennial plants followed by planned attacks using improvised explosive devices (IEDs) or weapons on first responders. Containers of viscous dark lubricating oil and traces of lubricants on the felled trees were usually found at the scene. These were suspected to be chain oil lubricant from the chainsaws used to cut down the trees used for the roadblock. This work aimed to differentiate the chromatographic patterns of used lubricating oils available in automobile repair shops from various locations across Thailand's southern border provinces. Lubricating oils were analyzed using gas chromatography/flame ionization detector (GC/FID) every two weeks to study their variation in chemical compositions over time. The results obtained from GC/FID were normalized for differentiation. This included four two-stroke, six four-stroke, and three recycled oils. Two lubricating oils found at an incident scene were also analyzed and the results compared with the chain oil from five seized chainsaws.
authors.affiliation: Department of Applied Science, Faculty of Science, Prince of Songkla University, Songkhla 90112, Thailand; Trace Analysis and Biosensor Research Center, Prince of Songkla University, Songkhla 90112, Thailand; Faculty of Technology and Environment, Prince of Songkla University, Phuket Campus, 80 Vichitsongkram Rd, Kathu, Phuket 83120, Thailand. Electronic address: aree.c@psu.ac.th.
authors.forename: Aree
authors.initials: A
authors.lastname: Choodum
authors.affiliation: Department of Applied Science, Faculty of Science, Prince of Songkla University, Songkhla 90112, Thailand; Central Institute of Forensic Science, Ministry of Justice, Bangkok 10210, Thailand.
authors.forename: Kijja
authors.initials: K
authors.lastname: Tripuwanard
authors.affiliation: Centre for Forensic Science, Department of Pure and Applied Chemistry, WestCHEM, University of Strathclyde, 204 George Street, Glasgow G1 1WX, UK.
authors.forename: Niamh Nic
authors.initials: NN
authors.lastname: Daeid
keywords: Chain saw oil; GC–FID; Thailand’s southern border provinces; Used lubricating oil