Marine Tar Residues: a Review

Abstract

Marine tar residues originate from natural and anthropogenic oil releases into the ocean environment and are formed after liquid petroleum is transformed by weathering, sedimentation, and other processes. Tar balls, tar mats, and tar patties are common examples of marine tar residues and can range in size from millimeters in diameter (tar balls) to several meters in length and width (tar mats). These residues can remain in the ocean environment indefinitely, decomposing or becoming buried in the sea floor. However, in many cases, they are transported ashore via currents and waves where they pose a concern to coastal recreation activities, the seafood industry and may have negative effects on wildlife. This review summarizes the current state of knowledge on marine tar residue formation, transport, degradation, and distribution. Methods of detection and removal of marine tar residues and their possible ecological effects are discussed, in addition to topics of marine tar research that warrant further investigation. Emphasis is placed on benthic tar residues, with a focus on the remnants of the Deepwater Horizon oil spill in particular, which are still affecting the northern Gulf of Mexico shores years after the leaking submarine well was capped.

Roles of Thermophiles and Fungi in Bitumen Degradation in Mostly Cold Oil Sands Outcrops

“…Other ecosystems that contain comparable highly diverse HMW hydrocarbons are marine tar balls (61) and asphalt lakes (62). Although the chemical and physical aspects of HMW hydrocarbon degradation in marine tar balls have been well described and biodegradation is suspected, no microbial community compositions have been reported (61). Asphalt lakes harbor small droplets of water, which were shown to have a subsurface origin and which contained a microbial community of 17 identified orders (62), of which all but 3 were also found to be major orders in the present study.…”

Solvent effects in the extraction and detection of polycyclic aromatic hydrocarbons from complex oils in complex environments

“…The chemical profile of oil spill oil collected directly from a Gulf of Mexico site has been well characterized in a number of references [26,27] and been shown to contain a diverse mixture of organic compounds including polycyclic aromatic hydrocarbons and a variety of more polar oxygenated metabolites [28]. Tar ball components have been similarly well-characterized using a variety of spectroscopic techniques [29][30][31].…”

Environmental stress in the Gulf of Mexico and its potential impact on public health

“…The use of unprecedented amounts of dispersants at the origin of the DWH oil spill is controversial because the natural behavior of deep oil spills is to remain deep below the surface, however, dispersants have already disrupted this natural process (Kleindienst et al, 2015; Lubchenco et al, 2012). Recent studies also indicate that the oil from DWH spill continues to resurface (Warnock et al, 2015). These oil deposits are suspected to be released continously to the surface due to chemical modifications (weathering) of the oil/dispersant complexes and/or by high pressure-induced emulsification of the oil (Gong et al, 2014; Lubchenco et al, 2012).…”