37
Benchmark Responses occurring was considered to be of
particular concern if this ratio exceeded one.
The EFSA CONTAM Panel concluded that there was a potential
risk1 that some children in groups with average and high
base diets could incur reductions of one IQ point as a result
of exposure to dietary lead. Exposure to additional lead from
frequent consumption of game, while not specifically evaluated,
would further increase this risk in those exposed. The EFSA
CONTAM Panel concluded that risk of cardiovascular effects
as a result of exposure to lead was very low for adult average
consumers across European countries. However, if exposure to
dietary lead was closer to the upper end of the range in adult
high consumers, the potential exists for some consumers to
have increased systolic blood pressure as a result of exposure
to lead. For nephrotoxicity, the EFSA CONTAM Panel concluded
that it is possible some consumers at the high and lowend of the
exposure ranges could potentially incur chronic kidney disease
as a result of exposure to dietary lead.
For consumers of an average base-diet, but also with frequent
consumption of game meat, the CONTAM Panel concluded
that there was a potential risk that some people could incur
cardiovascular and nephrotoxic effects as a result of exposure to
lead. This risk is increased over people not frequently consuming
game due to the relatively high lead levels in game.
In their summary conclusions, the EFSA CONTAM Panel
considered that [for the population in general] at current levels
of lead exposure there is only a low to negligible risk of clinically
important effects on either the cardiovascular systemor kidneys
of adult consumers. However, in infants, children and pregnant
women, there is potential concern at current levels of exposure
to lead for effects on neurodevelopment.
Frequent consumption by these most vulnerable groups of
game shot with lead ammunition would obviously increase
exposure.
Effects of lead on human health
not assessed by EFSA
Green and Pain (2012) also assessed studies of effects of lead
on Standard Assessment Test (SAT) scores of UK schoolchildren
and in rates of spontaneous abortion in pregnant women in
Mexico, which were not evaluated by EFSA. The SAT score
1 Where we have described groups potentially at risk of incurring critical effects the specific terminology used by EFSA is generally that ‘the possibility of an effect
cannot be excluded’(EFSA 2010).
study (Chandramouli et al. 2009) was not published in time to
be evaluated by EFSA, whilst the spontaneous abortion study
by Borja-Aburto et al. (1999) was available but not mentioned
in EFSA (2010).
Chandramouli et al. (2009) reported a negative association of
academic test results of UK schoolchildren at Key Stage 1 (SATs)
with B-Pbmeasured at 30 months of age. Green and Pain (2012)
used the relationship between the mean outcome of the SATs
writing test and blood lead to estimate the reduction in the test
score expected from a specified increase in B-Pb. EFSA (2010)
did not calculate a BMR for SATs scores. However, EFSA (2010)
defined the BMR for IQ as 1 IQ point, which is one-fifteenth
of the population standard deviation for IQ. To calculate an
equivalent change in SATs KS1 writing score to that identified as
the BMR for IQ, we obtained the maximum-likelihood mean and
standard deviation of SATs scores for children in England in 2010
(Department for Education 2013). The calculated values were
1.90 SATs grade points for the mean and 0.60 SATs grade points
for the standard deviation, where the SATs grades run from 0
(working towards Level 1) to 4 (Level 4). Hence, we took the
equivalent BMR for the SATs KS1 writing grade score to that used
by EFSA (2010) for IQ to be 0.60/15 = 0.04 SATs grade points.
Green and Pain (2012) used a statistical model fitted by Borja-
Aburto et al. (1999) to describe the relationship between B-Pb
and the proportion of pregnant women in Mexico City who
incurred spontaneous abortion. The model adjusted for the
effect of a previous history of spontaneous abortion. EFSA (2010)
did not evaluate this study or calculate a Benchmark Response
(BMR) for spontaneous abortion.
Potential risks to humans in the
UK from ammunition-derived
lead
Green and Pain (2012) used data on lead concentrations in UK
gamebirds, from which gunshot had been removed following
cooking to simulate human exposure to lead (Pain et al. 2010).
They combined this with UK food consumption and lead
concentration data to evaluate the number of gamebird meals
(of 200 g for adults; 118 g for a 6.9 year old and 100 g for a 2.5
year old child) consumed weekly that would be expected, based
upon published studies, to result in specified changes, over
and above those resulting from exposure to lead in the base
UK human health risks from ammunition-derived lead