A Nelson researcher is warning hunters that eating game meat killed with lead bullets could make them sick.
Dr Eric Buenz from the Nelson Marlborough Institute of Technology is part of a group of researchers trying to find out whether traces of lead can be found in game meat.
He said most hunters use lead ammunition, which can leave hundreds of fragments scattered throughout the animal's carcass and could be unknowingly ingesting lead.
"That's one of the nefarious things about lead - if you eat a large dose of it, you might feel bad immediately," Buenz said.
"But the bigger problem is that it's sequestered and kept in your bones. And when it's kept in your bones and your other soft muscle tissue, it's able to slowly leach out, so your body has this elevated, level of lead for a long time.
"When you have that elevated level of lead, it hurts basically every internal organ," he said.
Buenz said he was involved in the case of a man who was suffering from "an odd case" of gout.
"Normally, you would have gout in your small joints, but he was having it in his larger joints.
"When we got him off using lead ammunition, his lead levels went down, the gout went away.
"It's not something that, if you went to your GP and said you were having gout in your larger joints, it's not the first thing that comes to mind - are you eating lead-shot meat?"
Buenz is asking hunters to send in a sample of frozen mincemeat from an animal they've shot with lead or lead-free ammunition, so researchers can analyze its lead levels.
The research, which is part of an international consortium researching the use of lead ammunition in hunting, has just received an $8000 funding boost from the Maurice and Phyllis Paykel Trust.
Buenz said overseas studies have detected lead in 10 per cent to 50 per cent of meat samples tested.
He said lead-free ammunition typically costs more than lead bullets, which often puts hunters off making the switch.
"The cost of non-toxic ammunition always comes up," Buenz said.
"And I always say the same thing, which is that you're quite happy to spend $200 in petrol to drive to the place that you're going to go hunting, but you won't spend an extra dollar or two for the one bullet you might need to harvest the animal.
"That doesn't make sense to me. The cost of the bullet in the entire process of going hunting is really, pretty insignificant."