 The sediment records show a clear rise and fall of Hg pollution through history.Mercury concentrations in the River Thames decrease downstream from London to the outer Estuary with the total Hg levels ranging from 0.01 to 12.07 mg/kg, giving a mean of 2.10 mg/kg which is higher than many other UK and European river estuaries.The highest amount of sedimentary-hosted Hg pollution in the Thames estuary occurs in the central London area between Vauxhall Bridge and Woolwich.