Exploring the effects of an EDC mixture on growth and lipid accumulation in the marine diatom Phaeodactylum tricornutum

Sammanfattning

The awareness we are gaining about how many chemicals have an endocrine disruption potential and how easily they end up in big water bodies and bioaccumulate, leads us to wonder if they can affect organisms other than animals in the ecosystem. Phytoplankton is relevant to this research because ecologically very important, for producing half of the oxygen on Earth and being the base of food chains, but currently threatened by global change in many ways. Therefore, human actions that might affect its stability should be monitored. During this project cultures of the model marine diatom P. tricornutum were exposed to a mixture (G) of EDC known to disrupt metabolism in vertebrates’ development. G mixture contains five phthalates, three PFAAs, and triclosan in concentrations based on serum values from a cohort of pregnant women, part of the EU project EDC-MixRisk. These values were correlated with low birth weight of the children, and further studies have associated the exposure to G mixture with increased adipogenesis during development. The endpoints chosen for this study were bulk growth and lipid accumulation. Both are relevant ecotoxicological parameters for maintaining the ecosystemic balance; lipid accumulation alteration is a well-known indicator of stress response. The results showed a significant growth inhibition at concentration 100 times higher than in human serum, and a decrease in lipid accumulation. Further studies are suggested to confirm the results obtained, investigate effects of environmental relevant concentrations, and assess whether the substances studied are bioaccumulated in diatoms.