The Impact of Pesticides - Academy Publish

When this result (Figure 6) is combined with the results on pollution load (Figure 5)it can be concluded that although substantially more compounds are now monitored,this has not led to an increase in AE. A second point to be noted is that compoundsfor which the measured value does not exceed the Limit of Report do not contributeto AE either (for these were assigned a zero value), but obviously do contribute tothe total number of compounds over which the calculation is performed.CONCLUSIONSIn the Netherlands surface water pesticide levels still frequently exceed statutorylimits. Over the years, the relative area (amount of monitoring locations) of thecountry where there are no MPC exceedances has remained fairly constant.However, the absolute number of monitoring sites has increased, and the same trendcan be observed with respect to the number of sites where limits were exceeded.Certain compounds that were no longer on the market were nonetheless still foundin surface waters.The percentage of monitored compounds found in concentrations exceeding theMPC decreased from 4% in 1997 to 1% in 2009. The remaining problems are thusdue to only a small number of pesticides.The months in which the greatest number of compounds as well as monitoring sitesexceed the standards are May and July. At the same time exceedances are alsoobserved in periods in which fewer crops are grown, including the winter months.Although the regional spread of MPC exceedance varies, the highest environmentalloads are often to be found in the south-west of the country. As explained above,this load is calculated as the so-called Accumulated Exceedance (AE), covering amajor portion of the pesticides monitored.It can be concluded that pesticide loads in Dutch surface waters have declined, butnot everywhere. From 1998 to 2009 it can be said that in this respect there has beena 70% improvement in general water quality.ACKNOWLEDGEMENTSWe thank Nigel Harle for his translation of the Dutch and Maarten van ’t Zelfde forpreparing the figures. Martina G. Vijver is funded by NWO-VENI, project no. 86308 023.REFERENCESEuropean Commission, 2000. Directive 2000/60/EC of the European Parliament andof the Council of 23 October 2000 establishing a framework for Community actionin the field of water policy. OJ L 327, 22.12.2000, p. 1–73.European Commission, 2009. Commission staff working document accompanyingthe report from the Commission to the European Parliament and the Council inaccordance with article 18.3 of the Water Framework Directive 2000/60/EC onprogrammes for monitoring of water status. [COM82009)156], pp86.European Commission, 2003. Technical Guidance Document (TGD) on RiskAssessment of Chemical Substances (2nd edition). European Commission,European Chemical Bureau, Joint Research Centre, EUR 20418 EN/2.AcademyPublish.org - The Impact of Pesticides201