26 May 2012, PDF |
68 pages |
Moermond CTA, van Vlaardingen PLA, Vos JH, Verbruggen EMJ
RIVM Report 601714001
This report documents the RIVM's derivation of environmental risk limits for dimethoate in water. Dimethoate is an organophosphorus compound that is used as an insecticide in agriculture. The International Commission for the Protection of the Rhine (ICPR) has selected this compound as a Rhine-relevant substance within the Water Framework Directive. The RIVM used the most recent ecotoxicological and environmental fate data for deriving the Maximum Permissible Concentration (MPC). This resulted in a reduction of the calculated MPC for fresh surface water from 23 to 0.07 mug/L. No risk limits were derived for the sediment compartment because binding of the substances to sediment is considered to be negligible. The derivation procedure followed the methodology for the derivation of environmental risk limits as required by the European Water Framework Directive. Environmental risk limits form the scientific basis on which the interdepartmental steering group 'substances' sets the environmental quality standards. The government uses these quality standards for carrying out the national policy concerning substances and the European Water Framework Directive. Four different levels are distinguished: negligible concentrations (NC); a level at which no harmful effects are to be expected (maximum permissible concentration: MPC); the maximum acceptable concentration for ecosystems specifically for short-term exposure (MACeco) and a level at which possible serious effects are to be expected (serious risk concentrations: SRCeco).