Report from the Sub-comittee on the environment and health

would enable identification of those substances that, with <strong>the</strong> current
use, have <strong>the</strong> lowest safety margin for humans. However, since <strong>the</strong>
effects of <strong>the</strong> individual substances are not comparable, ranking alone
would not be enough but would have to be supplemented by an expert
assessment.
8.2 Precautionary principle and risk
The reasons for using a precautionary principle are as follows:
• The uncertainty and variation that are always associated with <strong>the</strong> data
on which decisions are based – with respect to both <strong>the</strong> individual
measurement and <strong>the</strong> generalisation <strong>from</strong> limited studies to <strong>the</strong> entire
environment or ecosystem and all <strong>the</strong> species and populations that are
to be protected.
• Some systems (e.g. meteorological and ecological systems) can in
some circumstances exhibit indeterminable, e.g. chaotic, behaviour. In
such cases it is in principle impossible to predict <strong>the</strong> consequences of
an exposure.
• Incomplete knowledge about how ecosystems are affected by and
react to pesticides and about <strong>the</strong> extent to which <strong>the</strong> systems can
regenerate or be re-established after a harmful exposure.
• The risk associated with making a mistake – i.e. underestimating a
risk with lasting consequences for humans and <strong>the</strong> environment.
• The desire to protect specially exposed groups, e.g. children, even
better.
• The fact that mistakes could have a serious future effect, e.g. through
accumulation of pesticides in groundwater or <strong>the</strong> atmosphere.
The “precautionary principle” has gained a considerable following in <strong>the</strong>
environmental field (Danish Environmental Protection Agency 1998c)
but has not been precisely defined. The following framing of <strong>the</strong> concept
can be used:
• The purpose of <strong>the</strong> precautionary principle is to provide greater
certainty that damage will not occur.
• The desire for more extensive use of <strong>the</strong> precautionary principle is
based on <strong>the</strong> view that nei<strong>the</strong>r <strong>the</strong> environment nor human health
should suffer as a consequence of behaviour about which <strong>the</strong>re is
scientific doubt or uncertainty.
• The precautionary principle allows <strong>the</strong> authorities to require less
evidence of a polluting effect <strong>from</strong> a given form of behaviour and to
take action to regulate <strong>the</strong> behaviour if <strong>the</strong>re is just some possibility of
pollution.
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