Water sources can be polluted by heavy metals, complex organic compounds such as petroleum by-products or pharmaceuticals, radioactive isotopes and trace elements ... rivers or the ocean and to better ...

The IAEA Environmental Laboratories produce certified reference materials for the measurement of radionuclides, trace elements and organic contaminants ... The labs also produce the Vienna Standard ...

Additionally, the mineral contains trace elements that ... not the overlying water column, although these are likely related. This is important for understanding past ocean chemistry from analyses ...