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Ecotoxicological information

Endpoint summary

Administrative data

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Additional information

The test item was investigated on aquatic organisms of different trophic levels (bacteria, invertebrates, fish, algae and aquatic plants). Acute toxicity tests (96 h) on two freshwater fish species, bluegill sunfish (Lepomis macrochirus) and rainbow trout (Oncorhynchus mykiss), resulted in LC50-values ranging from 0.22 mg/L to 0.34 mg/L (Based on analytically verified test concentrations in flow-through systems.). An acute toxicity test on freshwater invertebrates (Daphnia magna) revealed no toxic effect observable at 0.51 mg/L, the maximum solubility of the test substance. Thus, the LC50 value for invertebrates is greater than 0.51 mg/L (Based on analytically verified test concentrations in flow-through systems.).

For freshwater algae (Pseudokirchneriella subcapitata), no toxic effects occurred during a 96 h exposure up to the maximum solubility of the test item. Hence, the LC50 value for aquatic algae is greater than 1.26 mg/L. As an example for higher aquatic plants, duckweed (Lemna gibba) was exposed to the test substance at its maximum solubility of the substance in the teat medium. No toxic effects occurred under these conditions over a period of 7 days. However, it must be taken into account that the test substance fully degraded over the time span of the studies with Pseudokirchneriella and Lemna that were carried out under static conditions.

Focusing on environmental effects assessment, long term data obtained for chronic ecotoxicity of the formulation (fenoxaprop-P-ethyl + AE F122006) were used as read across. As the test compound consists of one active ingredient, a safener, and formulation additives, degradation or adsorption behavior of the active ingredient is not necessarily indicative of the behavior of the other ingredients. Since the toxicity cannot be unequivocally attributed to only the measured active ingredient or safener, no adjustment of results for measured concentrations was made. Therefore, all toxicity values were calculated based on the nominal concentrations of the fenoxaprop-P-ethyl + AE F122006 emulsifiable concentrate added to the test water.

Based on a prolonged toxicity test to the Rainbow Trout, Oncorhynchus mykiss, in a flow through system the NOEC is 0.42 mg/L. The NOEC of the chronic invertebrates test (In a static renewal exposure for 21 days) is 0.38 mg/L.

Using these values in the risk assessment represents a worst case situation for the risk assessment of the safener and is sufficiently adequate to cover the long term data.

Additionally, the effect of the test substance on microorganisms (activated sludge) was examined. In this test system, only a moderate inhibitory effect of 12.7% on microbial respiration was observed at nominal 1000 mg/mL which represents the highest concentration tested.