Registration Dossier

Diss Factsheets

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Short-term toxicity to fish

Isobutyl acrylate is considered to be acutely toxic both to freshwater and marine fish. The 96-hour LC50 of isobutyl acrylate for freshwater and marine water fish is 2.1 mg/L (measured).

Long-term toxicity to fish

In accordance with section 3 of REACH Annex XI (substance tailored exposure-driven testing), the study does not need to be conducted.

Short-term toxicity to aquatic invertebrates

Isobutyl acrylate is considered to be acutely toxic to freshwater invertebrates.The 48-hour EC50 was determined to be 8.2 mg/L (measured).

Long-term toxicity to aquatic invertebrates

Based on the read-across to n-butyl acrylate the 21-day NOEC of isobutyl acrylate was considered to be 0.136 mg/L.

Toxicity to aquatic algae

The 72-hour EC50, EC10 and NOEC (growth rate) of isobutyl acrylate was determined to be 5.28 mg/L, 2.09 mg/L and 0.82 mg/L (meas. arithm. mean), respectively.

Toxicity to microorganisms

The 30-minute EC50 of isobutyl acrylate was determined to be > 1000 mg/L (nominal).

Additional information

Short-term toxicity

Data concerning the acute toxicity in freshwater organisms are available for all three trophic levels (fish, aquatic invertebrates and algae). Effect values for short-term toxicity (LC/EC50) were all in the same range of concentrations, i.e. between 2.1 and 14.6 mg/L.

 

 

Freshwater fish

The LC50 value for Salmo gairdneri was 5.2 mg/L (measured) for the source substance n-butyl acrylate (BAMM 1990) and the LC50 value for Pimephalis promelas was approx. 2.1 mg/L (measured) for the target substance isobutyl acrylate (Russom et al. 1988). The structural analogue tert-butyl acrylate was tested in an acute toxicity study with Leuciscus idus under static test conditions without analytical monitoring and in an open system (BASF AG, 1978). Test concentrations were recalculated based on the nominal test concentrations at test start and the assumption that at test termination all concentrations were below the limit of detection (0.1 mg/L) as worst case. The 96-hour LC50 was recalculated to be 2.37 mg/L.

 

Thus, LC50 values for freshwater fish were between 2.1 and 5.2 mg/L.

 

 

Freshwater invertebrates

EC50 values for Daphnia magna were 8.2 mg/L (measured) for the source substance n-butyl acrylate (BAMM 1990), and 8.74 mg/L (measured) for the source substance tert-butyl acrylate (BASF AG, 2001), respectively. No acute toxicity studies in invertebrates involving analytical monitoring available for the target substance isobutyl acrylate.

 

Thus, EC50 values for freshwater invertebrates were between 8.2 and 8.74 mg/L.

 

 

Freshwater algae

For the target substance isobutyl acrylate the 72-hour EC50 values for growth rate and biomass were 5.28 and 3.18 mg/L (measured), respectively (BASF, 2002a). The NOEC was determined to be 1.65 mg/L. For the source substance n-butyl acrylate a 96-hour EC50 and NOEC (cell number) value of 2.65 mg/L and < 1.8 mg/L, respectively, was determined. The 72-hour EC50 and EC10 (growth rate) for the source substance tert-butyl acrylate were 14.6 mg/L and 5.61 mg/L mg/L, respectively (BASF AG, 2002b).

 

Thus, EC50 values for freshwater algae were between 2.65 and 14.6 mg/L. The NOEC values ranged from <1.8 to 1.65 mg/L.

Marine water fish

In a saltwater GLP study conducted with the source substance n-butyl acrylate in Cyprinodon variegatus (BAMM, 1996), the 96-hour LC50 was estimated to be 2.1 mg/L.

  

Long-term toxicity

A 21-day Daphnia magna Reproduction Test was performed with the source substance n-butyl acrylate under semi-static conditions in accordance with OECD TG 211 (BASF SE, 2009). The effect concentrations were based on the time-weighted mean analytically detected concentrations: NOEC (reproduction) = 0.136 mg/L; LOEC (reproduction) = 0.457 mg/L.

 

 

Aerobic microorganisms

The assessment of toxicity towards aerobic microorganisms was based solely on data acquired with the target substance isobutyl acrylate. The EC50 after 30 min exposure in a respiration inhibition test with domestic activated sludge according to OECD TG 209 was > 1000 mg/L (BASF AG 2001).

Categories Display