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Both effect and exposure assessment should be performed on an equal basis. It is therefore considered unreasonable to use a high organic matter content (sorption) in exposure assessment where on the effect side an extreme low (< 0.2%) organic matter content (sorption) is used. The most sensitive species tested in sand was T. pratense, with an EC50 (growth) of 19 mg/kg wwt. The sand used, consisted of >99.8% SiO2 and a particle size 150-210 µm. With loam soil (48.2% sand, 42.8% silt and 9% clay, 1.41% OC) alsoT. pratensewas the most sensitive species but with an EC50 (growth) of 309 mg/kg wwt. In the current assessment the PEC is calculated using an average Koc of 282624.3 L/kg based on soils with an average organic carbon content of 4.3% where on the effect side a test result is used with an organic carbon is used of <0.2%. This is considered extremely unrealistic. It was therefore justified to use the EC50 (growth) of 537 mg/kg dw which was tested on a soil with 1.41% organic carbon as a realistic worst-case lowest endpoint for the toxicity of the read-across substance C12-16 ADBAC to terrestrial plants.