2-(2-butoxyethoxy)ethyl methacrylate

Endpoint summary

Description of key information

LC50 fish (96h): 22.36 mg/l

EC50 daphnia magna (48h): 94.7 mg/l

EC10 daphnia magna (21 d): 7.51 mg/l (based on read across with 1,4 -Butanediol dimethacrylate)

ErC50 algae (72h). 95 mg/l

ErC10 algae (72h): 32 mg/l

Additional information

Freshwater aquatic toxicity studies with BDGMA were conducted in fish, invertebrates, algal and microbial species.

 

Short-term toxicity to fish

One acute freshwater study in fish is available for BDGMA, which is considered reliable without restriction (Klimisch score 1).

In a 96-h acute toxicity study according to OECD 203, rainbow troute (onchorynchus mykiss) were exposed to BDGMA at nominal concentrations of 0 (control), 80, 36, 17, 7.5 and 3.4 mg test item/L corresponding to geometric mean measured concentrations of 79.20, 33.48, 15.47, 6.53 and 2.79 mg test item/L under semistatic conditions.  

The 96-h LC50 was 22.36 mg/L (based on geometric mean measured concentration).

 

Short-term toxicity to aquatic invertebrates

One short term study to aquatic invertebrates with BDGMA is available acc. OECD 202 under static conditions which is considered reliable without restriction (Klimisch score 1). Daphnids were exposed at nominal concentration of 1; 2; 4; 8; 16; 32; 64; and 128 mg /L for 48 hr. 

The 48– hour EC50was 94.7 mg /L. 

 

Toxicity to aquatic algae

One study in freshwater algae is available for BDGMA, which is considered reliable without restriction (Klimisch score 1).

In a 72 hour acute toxicity study, the cultures of Desmodesmus subspicatus (Strain 86.81) were exposed to BDGMA to nominal concentration of 1; 2; 4; 8; 16; 32; 64; and 128 mg /L for 72 hrs.

ErC50 (72h) = 95 mg/l, ErC10 (72h)=34 mg/l, NOEC (72h)=32 mg/l.

 

Long-term toxicity to fish

Long-term testing in fish has been started in Feb. 2022 and results will be available in May 2022. This standard information requirement was waived for BDGMA since the substance is readily biodegradable and the risk characterisation shows that the PEC/PNECaqua ratio for the aquatic environment is <1, indicating no need for further information or testing. The information will be updated as soon as they are available.

 

Long-term toxicity to aquatic invertebrates

The long term toxicity to aquatic invertebrates was covered by read across to structurally related methacrylates to BDGMA. Currently, the OECD 211 with BDGMA is being conducted. The read across to other substances to cover this standard information requirement will be deleted and the dossier updated as soon as the data for long-term toxicity to aquatic invertebrates with BDGMA are available.

Current information used:

EC10 21 d to daphnia magna (reproduction) of the structurally related substance Ethyltriglycol methacrylate was 77.1 mg/l. Aquatic toxicity of the most methacrylates is known to be based on narcosis which correlates with log Pow.

There are data on 21d daphnia magna reproduction available for two methacrylates with the same log Pow of 3.1 as for Butyldiglycol methacrylates.

EC10 daphnia magna (21d) for Benzyl methacrylates is 3.34 mg/l (Ibacon 2012) and EC10 daphnia magna (21d) for 1,4 Butanediol dimethacrylates is 7.51 mg/l (Noack 2012). As 1,4 -Butanediol dimethacrylate has structurally higher correlation with Butyldiglycol methacrylate than Benzyl methacrylate, 7.51 mg/l will be used for PNEC derivation.

 

Toxicity to microorganisms

In accordance with column 2 of REACH Annex VIII, the activated sludge respiration inhibition test does not need to be conducted as this substance was found to be readily biodegradable and the applied test concentrations are in the range of concentrations that can be expected in the influent of a sewage treatment plant.