The efficacy of in-situ burning as a counter measure to oil spills in Arctic marine waters

点击翻译按钮获取中文摘要

As climate change brings reduced sea ice cover and longer ice-free summers in the Arctic, northern Canada is experiencing an increase in shipping and industrial activity in this sensitive region. Disappearing sea ice therefore makes the Arctic region susceptible to accidental releases of different types of oil and fuel pollution resulting in a pressing need for scientific knowledge to underlie regulatory policy formulation in this area. In situ burning (ISB) of spilled oil as an oil spill cleanup countermeasure is gaining acceptance because of its distinct advantages over other countermeasures. This technique can convert large quantities of oil into its primary combustion products, CO2 and H2O. It requires less equipment and labour and can be applied in areas such as the Arctic where many other methods cannot due to lack of response infrastructure and/or lack of alternatives. Burning of oil also produces dense black smoke primarily composed of black carbon (soot). These smoke particles can also contain (or be coated with) condensed organic compounds, sulphates. Burning also produces gaseous pollutants such as  CO, NOX, SO2, and a wide range of volatile organic compounds (VOCs). Of most concern are the more carcinogenic pyrogenically produced particle (submicron) bound multi-ring parent PAHs. This raises serious health concerns with respect to the potential for increasing concentrations of respirable particles and toxic gases from the burning of oil. Recent ISB studies conducted on oil sampled from the 2010 Deep Water Horizon Oil Spill, showed that the oil burning process doubled the concentrations of the polar aromatic compounds partitioning into the water phase. Using Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FTICR-MS) subsets of these compounds were identified as being highly condensed PAHs and the potentially more hazardous oxygenated compounds. While FTICR-MS is a powerful technique for the characterization of complex mixtures such as oil (and burned oil) the instrumental limitations constrain the structural predictions that can be made regarding the chemical composition. There is a strong need, therefore, to identify the structural characteristics of these water soluble polar organic pyrogenic compounds so as to better understand the pathways of their molecular production and unambiguous structural identifications and allowing for more comprehensive toxicological studies. This proposed research will identify and quantify water soluble pyrogenic transformation products and atmospheric emissions of various types of fuel oils when exposed to in-situ burning under varying Arctic marine environmental scenarios. It will provide vital information needed to conduct further environmental process and toxicological studies and contribute to ISB usage policies (alone or in combination with other mitigation technologies) needed by regulatory agencies, nongovernmental and Indigenous organizations, and the private sector.