PEARL and GeoPEARL are used to evaluate the leaching of pesticides to the groundwater, drainage of pesticides to surface waters and persistence of pesticides in topsoils. Primary aim is to support European and Dutch pesticide registration procedures. Metamodels of PEARL are used to evaluate policies, such as the EU Thematic Strategy on the Sustainable Use of Plant Protection Products.
Ton van der Linden
28 February 1957 - 25 January 2018
On January 25, Ton suddenly passed away at the age of 60. This was a shock for everybody who knew him. He was never ill and there were no signs whatsoever of a health problem.
In the morning he went to his office as usual. Nothing indicated that such a sad event was about to happen later that morning. With Ton the PEARL team has lost a fine and very loyal colleague.
Ton used to think in practical, but scientific sound solutions. No wonder perhaps, because he was born in a farmer's family. He had a lot of practical knowledge about farming practices.
In combination with his knowledge about pesticide fate and modelling this made him a unique person. In the Netherlands he was known as a "walking encyclopaedia".
Ton has achieved a long record in pesticide research. Together with Jos, he developed in 1989 one of the first pesticide leaching scenarios used for regulatory purposes. Around 1995, he stimulated Aaldrik to develop a spatially distributed pesticide leaching model. This development formed the basis for modern risk assessment in the exposure area, because this made the calculation of frequency distributions of the leaching concentration and the development of statistically sound exposure scenarios possible. Further, he has been member of EFSA's PPR-Panel for two terms and he has been working in several working groups, including many FOCUS working groups, EFSA working groups and national working groups, all with the aim to improve the quality of the regulatory pesticide risk assessment.
Our thoughts are first with his family. The PEARL team will never be the same without Ton, but we have a strong drive to continue all the good work that Ton has been doing in such a loyal and friendly manner.
Erik van den Berg
Daniel van Kraalingen
SOILPEARL_1_1_1_beta 6: New version of PEARL facilitates the use of EFSA tier 2A and tier 3B scenarios for exposure of soil organisms
EFSA developed six scenarios for exposure of soil organisms to plant protection products, which are implemented in a new version of PEARL. The practical use of these scenarios is described in the "EFSA Guidance Document for predicting environmental concentrations of active substances of plant protection products and transformation products of these active substances in soil", which has been published (
see EFSA). Please note that this version of PEARL is currently not intended for regulatory use. The new version uses SPIN (Substance PlugIN) to create, copy or modify substances for the use with the SOILPEARL application. SPIN should be installed prior to SOILPEARL. See ReadMe for more details.
Note that the new version uses SPIN (Substance PlugIN) to create, copy or modify substances for the use with the SOILPEARL application. SPIN should be installed prior to SOILPEARL. See ReadMe for more details.
Bug-fix version of Consensus-PEARL now available
Improved concepts for the description of volatilisation from soil and plants have been developed and implemented in a research version of PEARL. Hourly meteorological data can be input into the model to calculate hourly volatilisation fluxes. The fate of the pesticide on the plant surface is described as well, including transformation, penetration into the plant tissue and wash-off. In addition, the effect of increased sorption to the soil particles under dry soil conditions has been included. The first research version, Consensus_PEARL_1 has been developed and released in 2004 to support the work of the FOCUS Air workgroup. Since 2004, a few bugs have been eliminated and now a new version is available, ConsensusPEARL_3. This research version is not intended for standard authorisation calculations.
Linux version of FOCUS_PEARL_333 now available
Linux version of FOCUS_PEARL_333 now available (October 2009)
As Linux platforms have become more popular during the past years, A PEARL version based on the source code of FOCUS_PEARL_333 has been developed that can be run on Linux platforms.
GeoPEARL 3.3.3 suited for investigation of regional mitigation options
Version 3.3.3 of GeoPEARL is now available at our downloads page
. In the new version, the following options are added:
- an option to select soils with a property within a range specified by the user. Only soils for which the parameter values fall in the specified ranges are included in the assessment. This option is particularly suited for investigation of regional mitigation options, such as use restrictions.
- an option to calculate concentrations of compounds in the top layer of the soil for the purpose of future persistence asssessments.
GeoPEARL 3.3.3 is tested on Windows Vista.
The leaching concentration shifts to higher values if uncertainty is included in the risk assessment
Pesticide properties and in particular the half-life of the substance contribute most to the uncertainty in pesticide leaching concentrations. Furthermore, the 90th percentile leaching concentration shifts towards higher values if uncertainty is considered in the risk assessment. These are the most important findings of the uncertainty and sensitivity analysis of GeoPEARL.
MetaPEARL: An indicator to support the EU Thematic Strategy on the Sustainable Use of Pesticides
To monitor the progress of the EU Thematic Strategy on the Sustainable Use of Pesticides, the PEARL team has developed a simple pesticide leaching indicator. This indicator was developed using results from a pan-European, process-based, numerical pesticide leaching model (EuroPEARL).
FOCUS PEARL 3.3.3 is now available
FOCUS PEARL 3.3.3 is now available. FOCUS PEARL 3.3.3. is a so-called bug-fix release. We screened the sources and improved the speed of the model by almost 35% with no loss of functionality. This is good news for those doing a lot of calculations with the model. The new version is compatible with FOCUS PEARL 2.2.2. FOCUS PEARL 3.3.3 will be included in a new version of GeoPEARL, which will be launched soon as well.
The people behind the model
||These are the creators of the PEARL and GeoPEARL models (from left to right): Ton van der Linden, Erik van den Berg, Minze Leistra, Aaldrik Tiktak, Roel Kruijne, Jos Boesten, Joop Kroes and Daniel van Kraalingen.
Click on the photograph for a larger version.