Non-targeted, high resolution mass spectrometry strategy for simultaneous monitoring of xenobiotics and endogenous compounds in green sea turtles on the Great Barrier Reef Amy L. Heffernan a,b, ⁎ ,1 , Maria M. Gómez-Ramos c,1 , Caroline Gaus a , Soumini Vijayasarathy a , Ian Bell d , Christine Hof a,e , Jochen F. Mueller a , Maria J. Gómez-Ramos a,c a Queensland Alliance for Environmental Health Sciences, Faculty of Health and Behavioural Sciences, The University of Queensland, Brisbane, Australia b The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Melbourne, Australia c Agrifood Campus of International Excellence (CeiA3), Department of Chemistry and Physics, University of Almeria, European Union Reference Laboratory for Pesticide Residues in Fruit and Vegetables, Almería, Spain d Aquatic Species Program, Department of Environment and Heritage Protection, Townsville, Australia e Species Conservation and Indigenous Partnerships Unit, World Wildlife Fund for Nature-Australia, Brisbane, Australia HIGHLIGHTS •“Case-control” sampling of green sea turtles in three sites on Great Barrier Reef • Simultaneous detection of xenobiotics and biomarkers of effect • Anthropogenic influence, neuroinflam- mation and oxidative stress in ‘case’ an- imals • Demonstrated utility of green sea turtles as biomonitoring tool GRAPHICAL ABSTRACT abstract article info Article history: Received 19 January 2017 Received in revised form 12 April 2017 Accepted 2 May 2017 Available online xxxx Editor: D. Barcelo Chemical contamination poses a threat to ecosystem, biota and human health, and identifying these hazards is a complex challenge. Traditional hazard identification relies on a priori-defined targets of limited chemical scope, and is generally inappropriate for exploratory studies such as explaining toxicological effects in environmental systems. Here we present a non-target high resolution mass spectrometry environmental monitoring study with multivariate statistical analysis to simultaneously detect biomarkers of exposure (e.g. xenobiotics) and bio- markers of effect in whole turtle blood. Borrowing the concept from clinical chemistry, a case-control sampling approach was used to investigate the potential influence of xenobiotics of anthropogenic origin on free- ranging green sea turtles (Chelonia mydas) from a remote, offshore ‘control’ site; and two coastal ‘case’ sites in- fluenced by urban/industrial and agricultural activities, respectively, on the Great Barrier Reef in North Queens- land, Australia. Multiple biomarkers of exposure, including sulfonic acids (n = 9), a carbamate insecticide metabolite, and other industrial chemicals; and five biomarkers of effect (lipid peroxidation products), were de- tected in case sites. Additionally, two endogenous biomarkers of neuroinflammation and oxidative stress were identified, and showed moderate-to-strong correlations with clinical measures of inflammation and liver dys- function. Our data filtering strategy overcomes limitations of traditional a priori selection of target compounds, Keywords: Time-of-flight mass spectrometry Chemical exposure Non-target screening Marine wildlife Exposome Metabolomics Science of the Total Environment 599–600 (2017) 1251–1262 ⁎ Corresponding author at: Queensland Alliance for Environmental Health Sciences, 39 Kessels Rd, Coopers Plains, Queensland 4108, Australia. E-mail address: amy.heffernan@uqconnect.edu.au (A.L. Heffernan). 1 Co-first authors. http://dx.doi.org/10.1016/j.scitotenv.2017.05.016 0048-9697/© 2017 Elsevier B.V. All rights reserved. Contents lists available at ScienceDirect Science of the Total Environment journal homepage: www.elsevier.com/locate/scitotenv