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Title: Assessing the Impact of Agricultural Pesticides in the Aquatic Environment: Phase II
Author: Colin Brown
Author: Sabine Beulke
Author: Jeremy Biggs
Author: Chris Holmes
Author: Lorraine Maltby
Author: Wendy van Beinum
Author: Ryan Williams
Author: Marian Yallop
Author: Environment Agency
Document Type: Monograph
Annotation: Environment Agency Project ID:EAPRJOUT_1557, Representation ID: 546, Object ID: 2701; EAPRJOUT_1328, Representation ID: 437, Object ID: 2505; EAPRJOUT_1090, Representation ID: 341, Object ID: 2359
The overall aim of this project was to establish whether the normal use of agricultural pesticides leads to measurable adverse effects on aquatic invertebrates and plants. From this, the Environment Agency could develop a risk-based monitoring strategy for surface waters and provide field-based evidence to the Pesticides Safety Directorate (PSD) on whether the way that products are currently approved and used is precautionary. The project was broken into smaller tasks, the first of which, reported here, underpins the later monitoring phase of this work, by identifying sites vulnerable to pesticide contamination and designing a sampling programme. National-level risk mapping showed that crop type is the major driver for potential risk to the aquatic environment from agricultural use of pesticides. Orchards were identified as the crop type associated with the greatest potential risk. Crops more widely grown in England and Wales, such as cereals, oilseeds, potatoes and vegetables were found to be an order of magnitude smaller in risk than orchards. Landscape analysis using Geographical Information System (GIS) datasets and aerial imagery investigated the local characteristics of orchard cultivation for almost 1,500 individual stream segments adjacent to orchards in Herefordshire, Kent and East Anglia. Coupled with site visits, the analysis showed that conditions associated with the greatest pesticide exposure occurred very infrequently. Statistical analysis suggested that only relatively large effects of pesticides on aquatic communities would be detected using the empirical monitoring-based design. In locations where the greatest exposure to pesticides was anticipated, aquatic ecosystems generally lacked pesticide-sensitive organisms. Large, detectable changes in aquatic populations were therefore unlikely to occur. In addition, independent tests of passive sampling devices, the proposed chemical monitoring methodology for the project, showed that there were some gaps in the suite of chemicals that could be monitored and that some exposures would pass undetected because of their transient nature. The decision was therefore taken to terminate the project at the end of this design phase. Despite this, the question to be addressed - namely, establishing the significance of effects of pesticide use on aquatic life - remains extremely important from both a policy and scientific perspective. This report makes recommendations for an experimental study that might be considered for future research activities by the Environment Agency and PSD.
Publisher: Environment Agency
Subject Keywords: Geographical information systemsRisk assessmentPesticidesMonitoringAgricultureMapsCatchment basinsAquatic environment
Extent: 93
Total file downloads: 307

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