The
Commission’s proposals to amend the Drinking Water Directive (80/778/EEC) are
now available — the standard for total pesticides in water is now under threat
— and this summary outlines the issues non-governmental organisations will be
concerned about.
The proposal for a new Directive is explicitly aimed at the
quality of water intended for human consumption. Member states have to ensure
that such water meets
No
resource protection
The proposal does not aim to protect water sources,
but only to protect the quality of water that the consumer receives - at the
tap, the point of supply. Although there may be more proposals in the pipeline
to protect ground and other surface waters, so far there are no other elements
that would make up a complete water protection strategy.
The herbicides atrazine and simazine
have been widely restricted throughout most of the EU. As a result users have
simply changed to replacement chemicals. Already, increasing levels of these
replacement herbicides diuron, chlortoluron and isoproturon are found in water
in the UK.
No
environmental protection
The EC’s Fifth Environmental Action plan seeks a
reduction in pesticide use, a reduction in pollution and the integration of
water management and protection. Apart from a vague reference in the preamble to
the desk-ability of preventing pollution at source, and the need to apply
pesticides in a conscientious manner, the proposal focuses solely on end-of-pipe
solution.
Very low levels indeed of pesticide
pollution can be sufficient to endanger aquatic and other wildlife. Such
ecotoxicological values for pesticides are often lower than 0.1 µg/l.
Even smaller amounts can have adverse effects. Concentrations of TBT at 2
nanograms per litre (2 parts per hundred billion) can make whelks sterile.
Some degradation products of pesticides
may be more toxic than the parent pesticide, and more dangerous to aquatic fauna
and flora.
What
criteria?
The proposal announces its intention for pesticides of
relying on scientific evidence if appropriate and sufficient evidence is
available. If insufficient scientific evidence is available ‘a purely
precautionary approach has been adopted.’
Although the advice of the
Commission’s Scientific and Advisory Committee to Examine the Toxicity and
Ecotoxicity of Chemical Compounds will be sought, together with WHO’s advice
on drinking water guidelines, the Advisory Committee meets infrequently and the
WHO guidelines are available for a very limited number of pesticides only, and
many of these are older
No
limit for total pesticides
The 0.5 pg/l limit for total pesticides has been
abandoned. This limit functioned as a crude protection against the potential
synergistic or ‘cocktail’ effect of pesticide mixtures in water.
Now in effect, there will be no bar to higher total levels of
pollution of many pesticides in water, provided they do not individually breach
the 0.1 µg/l
threshold.
Monitoring
and analysis
The Directive proposes a minimal regime for monitoring
pesticides in drinking water. There is no duty to monitor for pesticides that
are not expected to be present: however, it is only by a wide and precautionary
programme of monitoring that a proper alert against the presence of pesticides
in water can be maintained.
Analysing for pesticides in water is
difficult. For many pesticides and many of their toxic breakdown products,
suitable analytical techniques still have to be developed. The Commission’s
own scientific advisors have pointed this out.
Parliamentary
involvement
The Management Committee envisaged by the Directive
will have the power to advise on monitoring strategies, analytical methodology
and parametric values.
This raises the twin questions; how
open the Committee will be, and will it tender technical or political advice?
Will it publish agendas, minutes, or be open to representations? Although the
Commission should have access to expert advice, how far will the advice go on
issues such as acceptable risk, which is a political role and which usurps the
role of parliament?
Derogations
Member states are allowed to make derogations,
permitting the 0.1µg/l
parameter to be breached ‘in exceptional circumstances for geographically
defined population groups’ -but no guidance is given about what should be done
to bring the water supply into compliance. An action plan to remedy the
situation has to be approved by the Management Committee. Unlike the recent
Uniform Principles, no duty is laid on Member States to ensure that conditions
of use of pesticides are changed or authorisations are withdrawn if the
pesticide appears likely to continue to breach the parameter.
Next
steps
The Commission has now to adopt the proposal, which
will then be presented to Parliament for its approval together with that of the
Council and the Economic and Social Committee, which may take another year. (PB)
Commission
of the European Communities, COM(94) Brussels, Proposal for a Council Directive
concerning the quality of water intended for human consumption, 1994, 90pp.
[This article first appeared in Pesticides News No. 26, December 1994, page 17]