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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Administrative data

Hazard for aquatic organisms

Hazard for air

Hazard for terrestrial organisms

Hazard for predators

Additional information

Conclusion on classification

Two studies are available on 4-acetoxystyrene: an acute daphnia study in accordance with OECD 202 and an algae study in accordance with OECD 201. These tests yielded the following results:

- daphnia 48h EC50 = 1.66 mg/L (nominal concentration)

- algae 72h EC50 (growth rate) = 2.45 mg/L (measured, geometric mean)

- algae EC10 = 0.715 mg/L (measured, geometric mean)

Based on the criteria described in CLP section 4.1.2, classification for acute aquatic hazard is not required as the available EC50 values are > 1 mg/L.

With regard to long-term aquatic hazard, the classification needs to be determined in two ways, and the most stringent outcome to be retained:

i) based on the available chronic data for algae. As the EC10 is in the range of 0.1 - 1 mg/L, and taking into account that the substance is readily biodegradable, classification as Chronic Cat. 3 is warranted.

ii) based on the available acute data. The EC50 values are in the range of 1-10 mg/L. However, taking into account that the substance is readily biodegradable and has a log Kow < 4, classification for long-term aquatic hazard is not warranted.

Adopting the most stringent classification determined by methods i) and ii), it can be concluded that 4-acetoxystyrene is to be classified as Chronic Cat. 3.