Phosphonic acid, monoethyl ester, sodium salt (1:1)

Toxicity to terrestrial arthropods

Link to relevant study record(s)

Reference

Endpoint:

toxicity to terrestrial arthropods: short-term

Data waiving:

other justification

Justification for data waiving:

other:

Description of key information

No effects in terrestrial arthropods are expected, thus further testing can be omitted.

Additional information

In accordance with Regulation (EC) No 1907/2006, Column 2 of Annex IX, section 9.4, toxicity tests on terrestrial organisms do not need to be investigated if the outcome of the chemical safety assessment shows no indication of risk on terrestrial organisms from exposure to the substance in question. The vapour pressure of the substance is below the limit of detection, thus the compound is unlikely to evaporate and air cannot be considered as route of exposure for this substance. Due to the high water solubility of Fosetyl-sodium (770 g/L at 20 °C and pH 5) and the low log Kow (log Kow= - 2.5 at 20 °C and a pH of 2.5 – 2.6) water is the main exposure route for this substance. Because the compound is inherently biodegradable (86.9% biodegradation after 28 days based on BOD and > 99.9% biodegradation after 28 days based on residue analysis), it is not considered to be persistent in the aquatic environment. However, the log Koc for Fosetyl-Sodium ranges from 2.79 – 3.96 (Koc = 613.9 – 9216 L/kg), therefore, the substance shows potential for adsorption to the soil compartment. For the terrestrial compartment one short-term toxicity test with the earthworm Eisenia fetida is available, which resulted in a 14-day LC50 of > 1000 mg/kg soil dry weight. Furthermore, a short-term study on the toxicity of Fosetyl-Sodium on the seed germination and root elongation of 10 plant species is available. The results of the study showed that the test substance had no effects on seed germination and root elongation in any of the 10 plant species up to the highest tested concentration of 1000 mg/L (nominal). In the aquatic environment, the lowest chronic effect value was observed for Daphnia magna with a NOEC (21 d) of≥10 mg/L (nominal). No acute aquatic effects were observed in any of the three trophic levels fish, daphnia, and algae (LC/EC50 > 100 mg/L, nominal). In conclusion, taking into account the physio-chemical parameters of the substance and the lack of acute terrestrial effects combined with the lack of acute and chronic aquatic effects, no effects on terrestrial arthropods are expected and further testing can be omitted.