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Ecotoxicological information

Toxicity to microorganisms

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Link to relevant study record(s)

Description of key information

Klimisch 1 study (Egeler P, Goth A (2010): activated sludge respiration inhibition test for GaAs according to OECD 209: EC50(3h) = 317.0 mg GaAs/L and EC10 = 4.6 mg GaAs/L (nominal values). Test was conducted with GaAs-powder; this physical form, however, is not relevant for the industrial production/use of GaAs where this substance is only present as a massive or as wafers. No toxicity data based on massive/wafer GaAs are available. Reported effects based on GaAs powder should therefore be considered as a worst case, predominantly reflecting the powder GaAs toxicity . 

Key value for chemical safety assessment

EC50 or LC50 for microorganisms:
317 mg/L
EC10, LC10 or NOEC for microorganisms:
4.6 mg/L

Additional information

A clear concentration-response relationship was observed and the following nominal ECx were determined for GaAs powder:

- EC50= 317.0 mg GaAs/L

- EC10= 4.6 mg GaAs/L

- EC20= 19.6 mg GaAs/L