Lead in aquatic environments – understanding the science

There have been many studies on the impacts of lead on human health, but it is only in recent years that our understanding of its environmental impacts has increased significantly. Much of this new understanding has been developed by independent academic institutions that have undertaken research sponsored by the ILA. The different areas in which significant progress with targeted scientific and regulatory goals has been made include the development of methods and models needed by stakeholders for realistic and site-specific assessment of lead impacts in freshwaters and better understanding of dietary and marine lead.

Recently, the ILA sponsored environmental research programme reached a significant milestone with the development of the lead Biotic Ligand Model that will be used for many years as the gold standard tool for setting site-specific water quality standards for freshwater ecosystems. We now understand that the presence of organic matter in the water in the form of dissolved organic carbon (DOC) strongly reduces lead toxicity. In fact, DOC is more important than water hardness in freshwaters, despite the fact that some existing regulatory water quality standards around the world currently account for the effects of hardness and not DOC. The effects of lead from dietary sources are minor. The information generated has already been used in the risk assessment framework for European REACH and is under consideration for regulatory uses in Australia, Canada and the US.

A new factsheet is now available that summarises what is known about the fate and effects of lead in freshwater and marine environments. This factsheet provides information on the current state of science and regulation, and highlights that in most situations, lead does not appear to have a marked effect on aquatic ecosystems. To download click here: Lead in Aquatic Environments.

For further information please contact ILA Senior Scientist, Jasim Chowdhury at [email protected].