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Generating data for oil spill models: Applications of passive dosing of polycyclic aromatic compounds with marine microalgae
DescriptionMathematical models predicting the toxicity of individual polycyclic aromatic compounds (PAC) play a pivotal role in providing stakeholders with essential insights for anticipating effects, assessing damage, and prioritizing vulnerable habitats in the event of an oil spill. Despite their importance, toxicity tests with PACs pose challenges, primarily due to compound loss through adsorption and volatilization during exposure. Passive dosing techniques emerge as a valuable solution for dosing exposure media and maintaining consistent exposure concentrations throughout the test duration. In this study, we investigated the toxicity of six selected PACs (9-fluorenone, 1-methylnaphthalene, dibenzothiophene, phenanthrene, pyrene, and fluoranthene) to the model marine flagellate Dunaliella tertiolecta (DT). DT, chosen for its ease of cultivation and wide temperature tolerance, proved ideal for temperature toxicity studies. Exposures were conducted at 15, 20, and 30°C to explore the influence of temperature on PAC-induced algal growth inhibition. Additionally, we assessed the impact of photomodification on algae growth by subjecting passively dosed dibenzothiophene, pyrene, 1-methylnaphthalene, and fluoranthene test solutions to UV light. The study revealed that growth inhibition occurred selectively with certain PACs, and warmer temperatures intensified the inhibitory effects of methylnaphthalene. EC50 values derived from the experiments were utilized to compute species- and temperature-specific critical target lipid body burdens (CTLBBs) for DT, a species not previously considered in the target lipid model (TLM) acute toxicity database. Surprisingly, photomodification of single PACs had no discernible effect on the observed toxicity of the three tested compounds. The data generated in this study contributes to refining oil spill models and enables comparisons of the sensitivity of different algal species to compounds recognized as primary contributors to crude oil toxicity. This research enhances our understanding of PAC toxicity dynamics and provides valuable insights for improving environmental risk assessments associated with oil spills.
Event Type
Paper
TimeTuesday, May 14th4:10pm - 4:30pm CDT
Location298-299
Tags
Preparedness