3.5. Effects of Phosphorus Fertilizers on Metal Element Release in Groundwater. The association of high levels of arsenic and multiple metal elements in groundwater has been described, although the relationship remains undefined.29−31 At the end of 4 months of anaerobic incubation, the aqueous phases of the microcosms from sampling site ASYL718 were analyzed for multiple metal elements by ICP-AES as the microcosm released a higher amount of As(III).