PARENT SESSION
PM16 - Probabilistic Ecological Risk Assessment
Monday, 18 November 2002
8:00 AM to 6:30 PM
Exhibit Hall
(P367) The variability of pesticide drift exposure.
Koch, Heribert*,1, Weisser, Peter1, Landfried, Mark1, Strub, Oliver1, 1 State Agency for Agronomy and Plant Protection, Mainz, Germany
ABSTRACT- After visualising drift patterns in off-crop habitats drift deposition was quantified in order to assess the exposure to NTOs. Sampling of leaves and measuring the deposits was carried out after the application with standard and drift reducing nozzles. A tracer was used (sodium-fluorescein). Both atomiser types showed the expected deposition gradient. Samples were investigated at 1, 3, 5 and 10 m apart from the sprayed area in meadows. Due to fast changing wind conditions on a small scale level samples showed a wide variation of deposits (ng/cm2 plant surface) ranging over 2 magnitudes. With drift reducing nozzles no deposit was found at the 10m line to be above the limit of detection. In higher meadows (40 cm) even higher variation occurred. Investigations in hedges samples were taken in a three dimensional grid. Results showed lower exposure with higher variation.
Key words: pesticide drift, exposure, off-crop habitats, non-target plants