There is also some research in the States that in areas where there is a lot of wildfowling that iron salts in the water are starting to cause problems! Iron is much, much more soluble in cold water than lead! Still I suppose we mustn't let facts get in the way of a "good" policy!
David.
Makes me laugh all this talk of non toxic saving the environment. Everything that is being pushed as an alternative is just as toxic to the environment , if not more toxic than lead. I worked for the EA as an enforcement officer for a while, specifically with fisheries, we knew of streams in our catchment that were devoid of life because of high levels of naturally occurring metals plus watercourses devoid of life because of iron contaminated water from mines etc.
Yes we know lead is toxic (at certain levels) to humans and the environment, but so is iron, copper, aluminium and a host of other naturally occurring metals.
From what I've read, no game shot with lead has failed World Health Organisation recommendations on lead content, there is no actual evidence of people being harmed by consuming game shot with lead.
In fact if you test anything made using grain such as wheat, barely etc, all will contain traces of metals simply because the plants naturally absorb heavy metals whilst growing and concentrate them in the seed. People who have been poisoned by lead have usually been exposed to it or consumed it via other mechanisms.
The main argument seems to be the damage caused to the environment by having areas where densities of spent shot are high, this contamination will continue, even if we loose lead, it will just be with another substance. Personally I think that where there may be high concentrations of lead shot, the simple answer is to limit the amount that may be deposited over an area per year, wouldn't be hard as we know the weight of a cartridges shot load and shoots could stipulate the required cartridge, hence knowing how many shots may be fired over a particular drive per year and which drives to "rest" on a rotor.
It could also be argued that since most Drives take place through woodland, the threat to contaminated crops and water courses is limited and so could be permitted to have heavier levels of spent shot.
This style of management is nothing new, farmers are restricted on how many kgs of nitrogen they can spread (natural and artificial fertilizer), factories have to limit levels of harmful substances discharged into rivers, where they use abstracted water for manufacturing.
Rough shooting / walked up / pigeon decoying, the spent shot densities are low compared to large commercial shoots, so would be outside the scope of the management system.
In regards to energy levels / range /effective killing, unless another substance that is a soft as lead and the same density is found, nothing will be as effective as lead when used in a shotgun (plus I hate copper bullets in rifles, having used them for contracts) you can not alter the laws of physics!!!!!!
End of rant, tin hat on.