Using the polychaete Arenicola marina to determine toxicity and bioaccumulation of PAHS bound to sediments

Abstract

The present study was conducted to evaluate a sediment toxicity and bioavailability test with the polychaete Arenicola marina as a potential tool to assess sediments contaminated by oil spills. A bioassay using the lugworm Arenicola marina was carried out in order to determine toxicity and bioaccumulation associated with the contaminants present in the fuel oil extracted from a sank tanker. After 10 and 21 days of exposure to sediments with different proportions of fuel oil (0.5, 1, 2, 4 and 8%) polychaetes were sampled to determine the mortality and the levels of individual PAHs in the organisms. During the experiment, mortality was recorded and the concentration (percentage of fuel oil) that provokes the mortality of the 50% of the Arenicola marina population exposed was calculated for both sampling dates (LC50(10) = 6.4%; LC50(21) = 2.4%). Bioaccumulation was mainly produced for fluoranthene, pyrene, benzo(b)fluoranthene and benzo(k)fluoranthene, whereas phenantrene and anthracene where initially accumulated and then metabolized. The results obtained in the present study suggest Arenicola marina can be a suitable species for assessing PAHs toxicity and bioaccumulation as part of oil spill management.