Photo-enhanced toxicity of dispersed and burned crude oil to Arctic mussels
Photo-enhanced toxicity of crude oil is real and mussels inhabit the photic zone. Photo-enhanced toxicity, (i.e. the increase in toxicity associated with the presence of sunlight), of oil and dispersed oil has been identified in many studies over the past 20 years to various marine species. determined that light enhanced the toxicity of crude oil 2 - 100 fold and the toxicity of anthracene, fluoranthene and pyrene (chemical compounds in oil) 12 - 50,000 fold. An oil spill in Arctic regions during the summer would expose oil to sunlight for 24 hours per day and may result in significant photo-enhanced toxicity. There is a lack of knowledge on the toxicity of burned oil to Arctic/Subarctic species. Bay mussels (Mytilus trossulus) are an integral component of coastal ecosystems and an important food source for both wildlife and humans.
This project studies the direct effects of oil, dispersants, and in-situ burning, along with photo-enhanced effects, on several physiological, biochemical, and metabolic aspects of a cold-water species of mussel (Mytilus trossulus). Previous research has demonstrated that these organisms, when directly exposed to chemically-dispersed oil during a simulated spill event, exhibit physiological stress. Over 20 years of scientific studies in Prince William Sound indicate that sunlight-exposed oil can be more toxic to aquatic organisms than non-weathered oil, yet there remains little information on what effects (if any) dispersants and in-situ burning have on bay mussels in the Arctic environment when exposed to sunlight, which in the summer months is continuous. This study will determine if dispersed oil or burned oil are more toxic to bay mussels than oil alone and if these effects are more pronounced during periods of long sun exposure.