Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

Data availability

For n-BMA acute studies of sufficient reliability are available for all three trophic levels, as well as reliable microbial toxicity data. Regarding the long-term toxicity of n-BMA test data are available for algae and invertebrates, but no long-term fish test. Based on a QSAR for the lower alkyl methacrylate category and the results of the exposure assessment the chronic fish test is not necessary to perform the CSA. A peer-reviewed analysis of the long-term test data of the lower alkyl methacrylates by Staples (2009) indicates the absence of a consistent pattern of one particular trophic level being more sensitive than others. The availability of chronic fish data for two category members is regarded as sufficient for the assessment. Data on a series of 12 different marine organisms with the common metabolite of the category, methacrylic acid, indicate that marine species are not expected to be more sensitive to methacrylates than freshwater species (Sverdrup, 2001).


The test results for the aquatic toxicity of n-butyl methacrylate indicate that the test substance is toxic to fish (LC50 5.6-11 mg/L) and harmful to aquatic invertebrates (EC50 = 25 - 32 mg/L) and algae (31 - >100 mg/L). In the long-term toxicity tests, the relevant NOECs were in a range of 1.1 – 24.8 mg/L. In the QSAR the relevant NOEC was identified as 1.69 mg/L). In the most relevant microbial toxicity study an 18 h - EC10 of 253.6 mg/L was found based on the growth of Pseudomonas putida.