By Victoria Gill
Science reporter, BBC News
About 100,000 wetland birds are killed every year from poisoning by discarded lead ammunition, say scientists.
This is one of the conclusions of a report published on Thursday by the University of Oxford.
The report also suggests that the consumption of game shot with lead ammunition has a greater impact on human health than previously thought.
Scientists involved in the research say the evidence now supports a ban on the use of lead ammunition in the UK.
The report is a collection of research presented by experts who gathered at the Oxford Symposium on Lead ammunition last year. It includes findings from studies carried out by university academics and by conservation groups including the Wildfowl and Wetlands Trust (WWT) and the RSPB.
As well as the impacts of lead on the environment, researchers have investigated the effects on human health of consuming game containing traces of lead ammunition.
Lord Krebs, emeritus professor of zoology at the University of Oxford, and former chair of the UK Food Standards Agency, told BBC News that there was "an overwhelming body of evidence" that lead used in hunting was "a risk both to humans and to wildlife".
"On that basis," he told BBC News. "The advice would be that lead shot should be phased out."