A GC-MS system for the analysis of biomarkers and petroleum-derived contaminants in natural systems

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An Agilent GC-MS is requested to replace a 16-y.o. instrument that is critical to our research and that stopped functioning 4 years ago. The instrument is the workhorse of the laboratory and is exploited in a range of studies making use of organic biomarkers to decipher organic matter sources, processing and sinks, as well as petroleum-derived contamination sources and fate. The main scientific questions that will be addressed using the requested instrument are: (1) What are the changes in organic matter dynamics in the water column and sediments of estuarine maximum turbidity and hypoxic zones since the beginning of the century, and to what extent physical and biochemical processes lead to the decoupling between bulk terrestrial OM and its molecular and isotopic signatures? (2) What is the molecular-level composition of organic matter specifically associated with iron oxides in marine and lacustrine sediments? (3) What are the molecular and isotopic fingerprints of the major petroleum-derived contaminants transiting in the St. Lawrence waterways, and how do they change during dispersion and transport? (4) What are the concentration and nature of the LMWHC found at trace levels in ground and sea water? In addition, as part of on-going work on the stability of carbon storage reservoirs in high-latitude soils and wetlands under a warming climate, we will (5) Trace molecular scale processes of carbon transport from terrestrial to aquatic ecosystems using the distribution and isotopic composition of molecular biomarkers; and (6) Develop isotopic analyses of archaeal and bacterial lipids as tracers of methane cycling. We estimate that the number of GC-MS analyses carried out as part of these projects will be >1000 per year, with significant outcomes both at the fundamental and societal (applied) levels.