My main research interest is bioaccumulation and toxicity of pharmaceuticals in aquatic organisms. My research focus lies with ionic pharmaceuticals such as weak acids and bases. They will have different degrees of ion speciation depending on the surrounding pH and thereby also change their degree of organism partitioning. Ions, being charged, are less prone to enter across biomembranes then molecules, which should result in less bioaccumulation and reduced toxicity. If a shift in pH results in less ionization then, by default, bioaccumulation and toxicity may rise. So, why is a difference in pH so important to investigate? Well, aquatic environments, such as lakes, tend to have daily and seasonal pH fluctuations due to changes in lake metabolism. Changes in pH during an organisms more sensitive life stages can therefore result in higher toxicity and thereby a shift in population density, which ultimately can affect a lakes whole ecosystem. I will test the effect different water pHs have on partitioning, toxicity and bioaccumulation in aquatic organisms such as zooplankton and fish e.g. roach (Rutilus rutilus) and also in mesocosm experiments. My drugs of choice are NSAIDs, such as ibuprofen, naproxen, diclofenac and ketoprofen and SSRIs, such as fluoxetine and sertraline.