A study of 738 UK harbour porpoises (1990–2021) shows mercury levels rising about 1% annually, nearly doubling since the 1990s. Higher mercury burdens increased the risk of death from infectious disease, revealing persistent ocean contamination despite the Minamata Convention
Mercury occurs naturally in the earth’s crust, but human activities, such as mining and fossil fuel combustion, have led to widespread global mercury pollution. Mercury emitted into the air eventually settles into water or onto land where it can be washed into water.
