6. Fate behaviour in water NL part EM2.6

Revision of parameter for the (Dutch national) model TOXSWA v1.2.

Recently it was noted by user and model developers that for TOXSWA v 1.2 calculations a parameter needs correction.

The factor Cref, de “concentration pesticide at which Kom was observed” is default set to 0.001 mg/L in the TOXSWA model.  


This is not correct and should be replaced by the value 1 mg/L- to be inserted by the user. This value is in line with other exposure models and based on the OECD test guidelines for sorption studies.

Dependent on the substance properties this revision may have some effect on the predicted concentrations in water (will be lower) and sediment (will be higher).

The revised reference concentration for Koc can be used from now on in dossiers in (national) model calculations for the emission to surface water using the TOXSWA v 1.2. model. We request applicants to include this revision in -newly to be submitted- dossiers from April 1st, including resubmitted dossiers as a result of a request for additional information - when calculations of emission to surface water are involved.