Eat pheasant? You are probably consuming toxic lead shot, warn University of Cambridge researchers

Consumers who eat pheasant may have elevated levels of toxic lead in their diet, University of Cambridge researchers warn.

Their study found pheasants killed by lead shot retain many fragments of lead too small to detect by eye or touch, and too far from the shot to be removed without throwing away much of the meat.

Fragments of lead become lodged deeply within meat of gamebirds when they are killed by lead shotgun pellets.

“While lead gunshot continues to be used for hunting, people who eat pheasants and other similar gamebirds are very likely to be also consuming a lot of tiny lead fragments,” said Professor Rhys Green in the University of Cambridge’s Department of Zoology, and first author of the study published in PLOS ONE.

“It seems to have been widely assumed in the past that a lead shot embedded in a pheasant carcass remained intact, and could be removed cleanly before the pheasant was eaten – removing any health risk. Our study has shown the extent to which this is really not the case.

“By eating pheasant, people are also unwittingly eating lead, which is toxic.”

Researchers examined the carcasses of eight wild-shot common pheasants that were killed on a farmland shoot using lead shotgun ammunition and put on sale in a UK butcher’s shop. Small lead fragments were embedded in every pheasant, along with lead shotgun pellets in seven of them.

Up to 10mg of tiny lead shards were present per pheasant - all of them too small to be detected by eye or by touch.

But there is no known safe level of exposure to lead for humans.

It accumulates in the body over time and can cause long-term harm, including increased risk of cardiovascular disease and kidney damage in adults.

Lead is known to lower IQ in young children and affect the neurological development of unborn babies.

In an earlier study in rats, it was shown that more lead is absorbed into the body from smaller fragments than from larger ones.

Prof Green said: “One pheasant is a reasonable meal for two or three people. Consuming this much lead occasionally wouldn’t be a great cause for concern – but we know that there are thousands of people in the UK who eat game meat, often pheasant, every week.”

Every year in the UK, around 11,000 tonnes of meat from wild-shot gamebirds, mostly pheasant, are eaten - and virtually all pheasants shot in the UK for human consumption are killed using lead shot.

High-resolution CT (computerised tomography) scanning was used to locate the lead fragments in the pheasant meat in three dimensions for the study. The size and weight of the fragments was measured before the meat was dissolved, allowing larger fragments to be extracted and analysed to confirm they were lead.

They found an average of 3.5 lead pellets and 39 lead fragments of less than 1mm wide per pheasant. The smallest fragments were 0.07mm wide – at the limit of resolution for the CT scanner for specimens of this size.

The researchers say it is likely that even smaller fragments were also present.

They also found that the lead pieces were widely distributed within the birds’ tissues and some of the small fragments were more than 50mm from the nearest lead shot pellet.

Prof Green added: “It’s rare for people eating game meat to accidentally eat a whole lead shot, because they’re cautious about damaging their teeth and know to check for lead shotgun pellets in the meat. But the lead fragments we found in pheasant carcasses were so tiny and widely distributed that it’s very unlikely they would be detected and removed.”

Neither the UK or EU has regulations about the maximum allowable levels of lead in human food from wild-shot game animals.

But there are strict maximum levels for lead in many other foods including meat from cattle, sheep, pigs and poultry, and shellfish harvested from the wild.

Steel shotgun pellets offer an alternative to lead, but despite being recommended by UK shooting organisations there is very little evidence of a voluntary switch away from lead.

The UK Health & Safety Executive is, however, preparing a case for banning the use of lead ammunition for hunting in the UK, and the European Chemicals Agency is following suit in Europe.

Other game - including partridge, grouse and rabbit - is primarily shot using lead shotgun pellets, and wild deer are shot using lead bullets.

While hunters often remove the guts of deer carcasses to make them lighter to carry, the discarded guts, typically containing many bullet fragments, are eaten by wildlife, which suffer the harmful effects of consuming lead.

This research was funded by the RSPB.