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Better understanding of exposure levels came with the
pioneering research of Clair Patterson in the 1960s who
showed that contemporary lead body burdens were then
600 times higher than in pre-industrial humans (Patterson
1965, Settle and Patterson 1980) and that nearly all modern
environments were widely contaminated with lead – at levels
which were far from ‘normal’.
Through the late 1960s and into the 1970s, medical studies
were starting to focus in detail on the effects of chronic
exposure to low levels of lead, especially on children, although
the TEL industry were quick to dismiss early research owing
to methodological deficiencies (Wilson 1983). However,
the meticulous investigation of Needleman et al. (1979) was
undertaken to the highest methodological standards, and
convincingly demonstrated significant statistical correlations
between lead exposure (as measured by dentine lead levels)
and a range of educational and psychological deficits in
schoolchildren. Multiple further studies followed confirming
and elaborating these findings of low-level effects on human
development (e.g. Rutter and Jones 1983, Needleman and
Gatsonis 1990).
In response to this growing medical evidence, ‘safe’ levels
of lead in the USA (as determined by the Centers for Disease
Control and Prevention (CDC)) were lowered progressively
from a concentration in whole blood of 60 μg/dl in 1960, to 40
μg/dl and then 30 μg/dl in the 1970s, to 25 μg/dl in the 1980s,
10 μg/dl in the early 1990s, and most recently to 5 μg/dl in
2012 (CDC 2012).
The main political driver to address the issue of TEL in
petrol in the USA came, not primarily from health impacts,
but from the need to install catalytic converters to comply
with the 1970 Clean Air Act. Since lead ‘poisons’ the
platinum catalyst, there was a need to eliminate it from
petrol. However, health impacts had also been recognised
and the Environmental Protection Agency (EPA) feared that
technological developments might develop non-platinum
catalytic converters in the future. Accordingly, EPA released
Regulations requiring the phased reduction of lead in petrol
on health grounds also. Industrial interests challenged these
all the way to the Supreme Court, where ultimately they
lost, strengthening the EPA’s regulatory position. Issues of
risk, cumulative exposure and proportionality of regulatory
responses were central to these cases (Needleman 2000,
Needleman and Gee 2013).
REGULATION OF LEAD IN PETROL IN THE UK
Both research and regulation addressing lead in petrol in the
UK lagged behind that in the USA and Japan (the first country
to regulate against TEL) and is described by Millstone (2013).
In essence, governmental policy development was strongly
influenced by industrial pressure and justified on the basis of
scientific uncertainty, despite growing research evidence fromUK
studies as well as the significant body of research from the USA.
In the UK, progress towards lead-free petrol started to develop
momentum with the launch in January 1981 of the pressure
group, the Campaign for Lead-free Air (CLEAR). This influentially
brought together a very wide range of social interests
including mothers groups, five political parties, trade unions,
environmental health officers, schools, environmentalists
and many others (including 60% of General Practitioners and
90% of the public both determined by polls (Wilson 1983)) to
lobby for the elimination of lead from petrol. From the outset,
CLEAR’s position was to argue from the basis of best science,
both presenting syntheses of that knowledge to the public (e.g.
Wilson 1983) and bringing together key scientists to share new
data and information (Rutter and Jones 1983).
Althoughother national reviews (e.g.Jaworski 1978) had reached
quite different conclusions, up until then, UK Government
reviews had down-played the significance of the issue:
“Wehavenot beenable to come to clear conclusions concerning
the effects of small amounts of lead on the intelligence,
behaviour and performance of children.”
(Lawther 1980).
However, three years later, the substantial and independent
review of evidence by the Royal Commission on Environmental
Pollution came to quite different conclusions:
”We are not aware of any other toxin which is so widely
distributed in human and animal populations andwhich is also
so universally present at levels that exceed one tenth of that at
which clinical signs and symptoms occur.”
(RCEP 1983).
The Commission made 29 recommendations including the
need to urgently phase out lead in petrol, the need to change
European Directive 78/611/EEC (which set a minimum level of
lead in petrol), and the banning of lead shot and lead fishing
weights (below). Given the major pressure from civil society (as
documented byWilson 1983) the UK Government rapidly
David A. Stroud