Report from the Sub-comittee on the environment and health

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Annex 2
The general rules for risk assessment of environmental impacts
and classification of health impacts
1 Environmental impacts
1.1 Risk of persistence, mobility and bioaccumulation
With respect to properties relating to persistence, mobility and
bioaccumulation, it is judged whe<strong>the</strong>r <strong>the</strong>re is a risk of <strong>the</strong> prescribed
values for whe<strong>the</strong>r an product can be directly accepted being exceeded in
<strong>the</strong> given conditions of use. Initially, <strong>the</strong> available laboratory tests are
assessed. If, on this basis, it is judged that <strong>the</strong>re is no risk of use of <strong>the</strong>
product resulting in <strong>the</strong> acceptance values being exceeded, <strong>the</strong> product is
regarded as acceptable without fur<strong>the</strong>r tests. If, on <strong>the</strong> o<strong>the</strong>r hand, <strong>the</strong>
acceptance values are exceeded, <strong>the</strong> product cannot be authorised
without lysimeter tests or field tests that – assessed on <strong>the</strong> basis of a
“realistic worst case” situation with respect to used dosages, conditions
of use, climate, etc. – prove that use of <strong>the</strong> product does not imply an
unacceptable risk of persistence, leaching to <strong>the</strong> groundwater and
bioaccumulation.
1.2 Risk of effects on aquatic and terrestrial organisms
For <strong>the</strong> impact area, <strong>the</strong> risk assessment is based on <strong>the</strong> so-called
quotient method, in which <strong>the</strong> relationship between toxicity and exposure
is calculated, cf. The Uniform Principles, EU’s Council Directive
97/57/EEC.
1.3 Toxicity
It is judged whe<strong>the</strong>r <strong>the</strong> exposure exceeds <strong>the</strong> toxic level with a ≥1 x
(un)certainty factor of between 5 and 1,000, depending on <strong>the</strong> organism
and on whe<strong>the</strong>r <strong>the</strong> toxicity is acute or chronic.
The higher <strong>the</strong> quotient, i.e. <strong>the</strong> lower <strong>the</strong> exposure and/or toxicity, <strong>the</strong>
lower <strong>the</strong> risk <strong>from</strong> use of <strong>the</strong> substance.
The exposure (PEC = Predicted Environmental Concentration) is
estimated on <strong>the</strong> basis of <strong>the</strong> intended use with respect to dosage, method
of application, time of use, plant cover, etc.
The (un)certainty factor is intended to cover <strong>the</strong> variation in sensitivity
between species, extrapolation <strong>from</strong> acute to chronic effects and <strong>from</strong>
laboratory to field, etc.
The risk assessment is performed in stages. The first stage is a rough
estimate of PEC. If this concentration lies much (corresponding to at
least <strong>the</strong> (un)certainty factor) below <strong>the</strong> effect concentrations achieved in
<strong>the</strong> laboratory, <strong>the</strong> pesticide is regarded as acceptable with respect to <strong>the</strong>
area investigated without fur<strong>the</strong>r analyses. If, on <strong>the</strong> o<strong>the</strong>r hand, <strong>the</strong>
effect concentration is close to PEC, one moves to <strong>the</strong> next step, in which
<strong>the</strong> PEC calculation is refined so that PEC again approaches a “realistic
worst case”. In cases in which a “realistic worst case” PEC and <strong>the</strong>