Reprint of: Overview of avian toxicity studies for the Deepwater Horizon Natural Resource Damage Assessment

Abstract

The Oil Pollution Act of 1990 establishes liability for injuries to natural resources because of the release or threat of release of oil. Assessment of injury to natural resources resulting from an oil spill and development and implementation of a plan for the restoration, rehabilitation, replacement or acquisition of natural resources to compensate for those injuries is accomplished through the Natural Resource Damage Assessment (NRDA) process. The NRDA process began within a week of the Deepwater Horizon oil spill, which occurred on April 20, 2010. During the spill, more than 8500 dead and impaired birds representing at least 93 avian species were collected. In addition, there were more than 3500 birds observed to be visibly oiled. While information in the literature at the time helped to identify some of the effects of oil on birds, it was not sufficient to fully characterize the nature and extent of the injuries to the thousands of live oiled birds, or to quantify those injuries in terms of effects on bird viability. As a result, the US Fish and Wildlife Service proposed various assessment activities to inform NRDA injury determination and quantification analyses associated with the Deepwater Horizon oil spill, including avian toxicity studies. The goal of these studies was to evaluate the effects of oral exposure to 1-20ml of artificially weathered Mississippi Canyon 252 oil kg bw day from one to 28 days or one to five applications of oil to 20% of the bird's surface area. It was thought that these exposure levels would not result in immediate or short-term mortality but might result in physiological effects that ultimately could affect avian survival, reproduction and health. These studies included oral dosing studies, an external dosing study, metabolic and flight performance studies and field-based flight studies. Results of these studies indicated changes in hematologic endpoints including formation of Heinz bodies and changes in cell counts. There were also effects on multiple organ systems, cardiac function and oxidative status. External oiling affected flight patterns and time spent during flight tasks indicating that migration may be affected by short-term repeated exposure to oil. Feather damage also resulted in increased heat loss and energetic demands. The papers in this special issue indicate that the combined effects of oil toxicity and feather effects in avian species, even in the case of relatively light oiling, can significantly affect the overall health of birds.

Dermal exposure to weathered MC252 crude oil results in echocardiographically identifiable systolic myocardial dysfunction in double-crested cormorants ( Phalacrocorax auritus )

“…The Deepwater Horizon (DWH) oil spill in 2010 released 3.2 million barrels of crude oil into the northern Gulf of Mexico, exposing numerous species of animals to the toxic components of oil. A comprehensive assessment of morbidity and mortality caused by DWH oil exposure was undertaken by the DWH Natural Resource Damage Assessment (NRDA) Trustees to characterize ecosystem damages that encompasses damage to animal health (Bursian et al, 2017; DWH Trustees -Deepwater Horizon Natural Resource Damage), 2015). While the cardiotoxic effects of oil are well documented in fish, especially during embryonic development, there is minimal information of the cardiotoxic effects of crude oil in other vertebrates (Collier et al, 2014;Incardona et al, 2014).…”

Estimation of native and alkylated polycyclic aromatic hydrocarbons (PAHs) in seabirds from the south coast of the Baltic Sea

“…Contact with sufficient concentrations of PAHs may cause a broad spectrum of health effects in seabirds, from altering molecular and physiological processes to modifying hepatic and immune function, increasing physical deformities, reducing reproductive success and growth, and causing acute toxicity in birds covered with oil as an effect of oil spillage or even can lead to death (Albers 2006;Briggs et al 1997;Bursian et al 2017;Paruk et al 2016). Although the acutely lethal effects of oil exposure in birds following catastrophic oil spills are well known (Balseiro et al 2005;Newman et al 2000), the PAH chronic exposure among marine birds occupying industrialized coastlines is undocumented.…”

Effects of Repeated Sublethal External Exposure to Deep Water Horizon Oil on the Avian Metabolome

“…The Deepwater Horizon (DWH) oil spill in April 2010 brought forth many of these differences in deep-water drilling and its environmental effects. The DWH oil spill was the largest offshore marine oil spill in the world and unprecedented in terms of loss of human life and economic and environmental impacts 1,3 . Key among these differences is that the oil travelled hundreds of meters through the water column, from 66 km offshore, and the active spill continued for several months, ultimately covering 112,100 km 2 and exposing 2,100 km of shoreline off the coasts of Louisiana, Mississippi, Alabama and western Florida, USA 1,3 .…”

“…Large numbers of mortalities of wildlife including avian species have been documented in oil spills 4–6 and the DWH oil spill was no exception 3 . However, the DWH oil spill was unique for a number of reasons.…”