Toxicity of two representative petroleum hydrocarbons, toluene and phenanthrene, to five Atlantic coral species

Highlights: • Acute effects of phenanthrene and toluene tested via passive-dosing. • Sublethal and lethal endpoints were determined for five coral species. • Endpoints were used in Target Lipid Model to estimate body-burdens for comparison. • Corals tested showed resilience compared to other species previously evaluated. • Study provides model inputs for improved simulation of spill impacts to corals. Coral reefs are keystone coastal ecosystems that can be exposed to petroleum hydrocarbons from multiple sources, and when selecting spill response methods to limit environmental damages, corals represent one of the highest valued resources for protection. Because previous research to characterize the sensitivity of coral species to petroleum hydrocarbon exposures is limited, a continuous-flow passive dosing system and toxicity testing protocol was designed to evaluate the acute effects of two representative petroleum compounds, toluene and phenanthrene, on five coral species: Acropora cervicornis, Porites astreoides, Siderastera siderea, Stephanocoenia intersepta, and Solenastrea bournoni. Using analytically confirmed exposures, sublethal and lethal endpoints were calculated for each species, and used as model inputs to determine critical target lipid body burdens (CTLBBs) for characterizing species sensitivity. Further, quantification of the time-dependent toxicity of single hydrocarbon exposures is described to provide model inputs for improved simulation of spill impacts to corals in coastal tropical environments.