Dabrowski, James MBalderacchi, M2014-01-242014-01-242013-11Dabrowski, J.M and Balderacchi, M. 2013. Development and field validation of an indicator to assess the relative mobility and risk of pesticides in the Lourens River catchment, South Africa. Chemosphere, vol. 93(10), pp 2433-24430045-6535http://ac.els-cdn.com/S0045653513011867/1-s2.0-S0045653513011867-main.pdf?_tid=9180ac36-8438-11e3-80b8-00000aab0f6c&acdnat=1390486604_f9303337e9d48e925870388de6af36d6http://hdl.handle.net/10204/7173Copyright: 2013 Elsevier. This is the Pre-print version of the work. The definitive version is published in Chemosphere,vol. 93(10), pp 2433–2443A GIS based pesticide risk indicator that integrates exposure variables (i.e. pesticide application, geographic, physicochemical and crop data) and toxicity endpoints (using species sensitivity distributions) was developed to estimate the Predicted Relative Exposure (PREX) and Predicted Relative Risk (PRRI) of applied pesticides to aquatic ecosystem health in the Lourens River catchment, Western Cape, South Africa. Samples were collected weekly at five sites from the beginning of the spraying season (October) till the beginning of the rainy season (April) and were semi quantitatively analysed for relevant pesticides applied according to the local farmers spraying programme. Monitoring data indicate that physicochemical data obtained from international databases are reliable indicators of pesticide behaviour in the Western Cape of South Africa. Sensitivity analysis identified KOC as the most important parameter influencing predictions of pesticide loading derived from runoff. A comparison to monitoring data showed that the PREX successfully identified hotspot sites, gave a reasonable estimation of the relative contamination potential of different pesticides at a site and identified important routes of exposure (i.e. runoff or spray drift) of different pesticides at different sites. All pesticides detected during a monitored runoff event, were indicated as being more associated with runoff than spray drift by the PREX. The PRRI identified azinphos-methyl and chlorpyrifos as high risk pesticides towards the aquatic ecosystem. These results contribute to providing increased confidence in the use of risk indicator applications and, in particular, could lead to improved utilisation of limited resources for monitoring and management in resource constrained countries.enPesticidesToxicity endpointsLourens River catchmentRisk indicatorsArticleDabrowski, J. M., & Balderacchi, M. (2013). Development and field validation of an indicator to assess the relative mobility and risk of pesticides in the Lourens River catchment, South Africa. http://hdl.handle.net/10204/7173Dabrowski, James M, and M Balderacchi "Development and field validation of an indicator to assess the relative mobility and risk of pesticides in the Lourens River catchment, South Africa." (2013) http://hdl.handle.net/10204/7173Dabrowski JM, Balderacchi M. Development and field validation of an indicator to assess the relative mobility and risk of pesticides in the Lourens River catchment, South Africa. 2013; http://hdl.handle.net/10204/7173.TY - Article AU - Dabrowski, James M AU - Balderacchi, M AB - A GIS based pesticide risk indicator that integrates exposure variables (i.e. pesticide application, geographic, physicochemical and crop data) and toxicity endpoints (using species sensitivity distributions) was developed to estimate the Predicted Relative Exposure (PREX) and Predicted Relative Risk (PRRI) of applied pesticides to aquatic ecosystem health in the Lourens River catchment, Western Cape, South Africa. Samples were collected weekly at five sites from the beginning of the spraying season (October) till the beginning of the rainy season (April) and were semi quantitatively analysed for relevant pesticides applied according to the local farmers spraying programme. Monitoring data indicate that physicochemical data obtained from international databases are reliable indicators of pesticide behaviour in the Western Cape of South Africa. Sensitivity analysis identified KOC as the most important parameter influencing predictions of pesticide loading derived from runoff. A comparison to monitoring data showed that the PREX successfully identified hotspot sites, gave a reasonable estimation of the relative contamination potential of different pesticides at a site and identified important routes of exposure (i.e. runoff or spray drift) of different pesticides at different sites. All pesticides detected during a monitored runoff event, were indicated as being more associated with runoff than spray drift by the PREX. The PRRI identified azinphos-methyl and chlorpyrifos as high risk pesticides towards the aquatic ecosystem. These results contribute to providing increased confidence in the use of risk indicator applications and, in particular, could lead to improved utilisation of limited resources for monitoring and management in resource constrained countries. DA - 2013-11 DB - ResearchSpace DP - CSIR KW - Pesticides KW - Toxicity endpoints KW - Lourens River catchment KW - Risk indicators LK - https://researchspace.csir.co.za PY - 2013 SM - 0045-6535 T1 - Development and field validation of an indicator to assess the relative mobility and risk of pesticides in the Lourens River catchment, South Africa TI - Development and field validation of an indicator to assess the relative mobility and risk of pesticides in the Lourens River catchment, South Africa UR - http://hdl.handle.net/10204/7173 ER -