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fragments, small fragments or some combination of the three
types detectable by X-radiography.
Substantial fragmentation of lead gunshot occurs when
gamebirds and waterfowl are killed using gunshot.
X-radiographic studies show that gamebirds andmammals shot
either with lead gunshot or lead bullets often contained lead
fragments which were small, numerous and widely dispersed in
edible tissues away from the wound canals (e.g. Pain et al. 2007,
2010, Knott et al. 2010 for UK studies, and Dobrowolska and
Hunt et al. 2006, 2009, Melosik 2008, Krone et al. 2009, Grund et
al. 2010, for relevant studies elsewhere).
In addition to studies of lead ammunition and fragments
in dead animals and animal parts, numerous studies have
used X-radiography to investigate proportions of live birds,
predominantly wildfowl, carrying embedded gunshot in their
tissues. The proportion of animals, or parts thereof, shot using
lead ammunition which are potentially available to predators
and scavengers is unknown for some species, but may be high
for quarry species such as ducks and geese (see Table 1 for live
wildfowl), andmust represent hundreds of thousands of animals
potentially contaminated with ammunition-derived lead per
year entering the food supply of wild predators and scavengers.
Even in some protected species, such as swans, that cannot be
legally shot, a high proportion may contain embedded gunshot
(Newthet al. 2011, see Table 1).
Sales of non-lead ammunition in the UK are low. Use of lead
ammunition is permitted throughout the UK for the majority of
shooting. Restrictions on the use of lead gunshot apply to the
shooting of wildfowl and coot Fulica atra and moorhen Gallinula
chloropus anywhere in England and Wales, and also for any
species over certain listed wetland areas in these countries. In
Scotland and Northern Ireland restrictions apply to all shooting
with gunshot of any animal over wetlands, although all species
including wildfowl may be shot with lead ammunition away
from wetland areas in these countries. Wildfowl comprise a
small proportion of birds shot, and ammunition composed
primarily of lead is used for the vast majority of shooting of
game in non-wetland habitats. The use of lead ammunition to
shoot wildfowl has not been lawful in England since 1999, but
recent compliance studies (see Cromie et al. 2010, 2015) found
between 68 - 77% of wild duck carcasses bought from game
dealers in England had been shot using lead ammunition.
Hence, it is clear that the vast majority of game animals shot in
the UK are killed using lead ammunition.
AMMUNITION-DERIVED LEAD IN SOILS AND WATER
(HAVING ORIGINATED FROM INTACT GUNSHOT OR
BULLETS DEPOSITED IN THE ENVIRONMENT) (i.e. OF
RELEVANCE TO EXPOSURE ROUTE 3)
Wildlife may be exposed, primarily via ingestion, to lead
of ammunition origin that has moved from deposited lead
ammunition into the soil and water. While elemental lead
is very stable under neutral pH conditions, the surface
of ammunition will be chemically transformed in the
environment, and the lead compounds formed, which
will vary with soil conditions, will play an important part in
determining the mobility of lead. In water the solubility of
different compounds is related to pH, amount of calcium,
salinity and the presence of humic material.
Soils and sediments act as an environmental sink for lead. Lead in
soil may occur in a variety of chemical forms (e.g. as carbonates,
sulphides etc.) and fractions, e.g. including exchangeable,
adsorbed and organic complexes. Lead is strongly adsorbed
to soil organic matter, silicate clays, peat and iron oxides.
Consequently, under most conditions the majority of lead that
enters soils and is transformed into lead compounds is likely to
be retained in the upper layers and not leach to any great extent
into the subsoil and groundwater. However, although this is a
general rule, the mobility of lead in soils is nonetheless highly
variable in relation to environmental conditions and is thus
site specific. Research into the degradation/transformation of
metallic lead from gunshot or bullets, (e.g. see Cao et al. 2003,
McLaren et al. 2009, Sanderson et al. 2012, Sullivan et al. 2012)
illustrates the varied impacts temperature, moisture and soil
chemistry have on the rate of degeneration/transformation of
metallic lead gunshot or bullets, the transformation products,
and the rate of passage of lead and its transformation products
through the soil profile.
Under most environmental conditions gunshot degrades only
slowly and in addition to the chemical processes described
above, degradation may be influenced by physical erosion/
abrasion, which is accelerated in coarse and gritty soils and/
or those with considerable soil movement. Movement of lead
through the soil may also be influenced by other factors, such as
precipitation and snowmelt.
The National Sports Shooting Foundation (the trade association
for America’s firearms industry) has produced a report on ‘Lead
Mobility at Shooting Ranges’, a synthesis of which is given in its
Deborah J. Pain, Ruth Cromie & Rhys E. Green