Format for Proposal for Changing Scenario Input Data of FOCUS Groundwater Scenarios

Test results for FOCUS_TOXSWA_2.2.1

Standard drainage and runoff input files are used for this test[1]. These are coupled to a less and a more persistent compound in water, respectively FOCUS Compound A_sw and H_sw.

1. Model output for 3 applications of 1 kg/ha of FOCUS Compound A_sw to winter cereals (maize for R2) with the first appln at the day around emergence

2. Model output for 3 applications of 1 kg/ha of FOCUS Compound H_sw to winter cereals (maize for R2) with the first appln at the day around emergence

For substance A_sw the results of v1.1.1 and v2.2.1 are exactly the same.

For substance H_sw the PECs calculated with v1.1.1 and v2.2.1 differ slightly for most runs. The largest differences in global max if found for the D1-Ditch scenario, which is 0.206 g/L lower than the corresponding global max of FOCUS_TOXSWA v1.1.1. The largest difference in TWAC 28 d is found for the D2-Ditch scenario, which is 0.253 g/L higher than the corresponding TWAC 28 d of FOCUS_TOXSWA v1.1.1. The differences in calculated PECs are due to the tighter selection of the calculation time steps in the water layer for substances with Koc values between 10 and 100 L/kg (Koc of H_sw is 100 L/kg) (See the ‘Differences between TOXSWA_2.2.1 and TOXSWA_1.1.1’ document, item m1). The differences in PECs between v1.1.1 and v2.2.1 are smaller than 0.2%, so considered not significant.

[1] Please note that these runs are intended as a test for the TOXSWA software only. They do not correspond to sensible, consistent step 3 FOCUS runs that can be used for risk assessment purposes. (E.g. because PRZM and MACRO do calculations for a pesticide with D-sw properties, while TOXSWA performs calculations for a pesticide with A-sw or H-sw properties.)