Defra is not progressing any further investigative work into the presence of pyridine in the River Tees at this time. We are however finalising the development and validation of a detection method to reliably quantify the amounts of pyridine in crab tissues. Once completed, we will use this test to assess the levels of pyridine in environmental crab tissues associated with the impacted and non-impacted areas, to better understand the significance of pyridine in crustacea, including the potential for its endogenous production post-mortem. The Government Chief Scientific Adviser has conveyed an independent external expert panel to review all the scientific evidence relating to this issue and report published on Friday 20 January . Defra scientists continue to engage with the wider academic community with regard to ongoing research and development work into the ecological status of the Tees and the wider North Sea.