2-Propenoic acid, 2-propylheptyl ester

Long-term toxicity to aquatic invertebrates

Description of key information

To assess the long term effects on aquatic invertebrates two studies with ethyl acrylate and n-butyl acrylate were conducted. The most sensitive NOEC of 0.14 mg/L (reproduction) was obtained for Daphnia magna after 21 days of exposure to n-butyl acrylate. 

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

0.14 mg/L

Additional information

No experimental data on 2-propylheptyl acrylate are available. Therefore, the long term effects on aquatic invertebrates were assessed by experimental data on the structural analogue ethyl acrylate (CAS 140-88-5) and n-butyl acrylate (CAS 141-32-2).

The 21-day chronic study with ethyl acrylate in Daphnia magna was conducted under flow-through conditions according to EPA OTS 797.1330 (BAMM, 1997). Four replicate test chambers per control and each test concentration were grouped and assigned to the mean measured treatment concentrations 0.19, 0.45, 0.73, 1.7, and 3.2 mg/L. Initially, there were 10 daphnids per replicate chamber. Daphnids in all concentrations were observed once daily for immobility and other abnormal effects such as surfacing, trialing extraneous material quiescence, and /or tending to the bottom of the test chamber. Survival of Daphnia Magna was shown to be significantly affected in the 0.73, 1.7 and 3.2 mg/L mean measured test concentrations as compared to the control. At 21 days three categories of response variables were analyzed: survival, reproduction and growth. Effect concentrations based on measured values were as follows:

EC50 (immobility/mortality) = 0.5 mg/L

NOEC (reproduction) = 0.19 mg/L

LOEC (reproduction) = 0.45 mg/L

MATC (reproduction) = 0.29 mg/L

For n-butyl acrylate a 21 -day Daphnia magna Reproduction Test was performed under semi-static conditions in accordance with OECD TG 211 and GLP regulations (BASF SE, 2009). 0, 0.1, 0.22, 0.46 and 2.2 mg/L were tested as nominal concentrations based on test substance mass. For each concentration 10 animals were examined in replicates. Significant effects on reproduction and /or growth were observed for test groups > 1.0 mg/L. The effect on reproduction was the most sensitive end point. The data was not sufficient to calculate ECx values for reproduction or growth. No mortality was observed among parent animals over the 21d exposure period (21 d EC0 > 2.2 mg/L). No additional adverse effects or abnormal behaviour were observed in any of the test treatments. Since the measured concentrations deviated markedly from the nominal concentrations, the effect concentration, which is based on the time weighted mean analytically detected concentrations should be preferably used for the evaluation of the test substance. The most sensitive effect values were concerning reproduction:

NOEC (measured, TWA) = 0.136 mg/L

LOEC (measured, TWA) = 0.457 mg/L.

Survival of the parent or young daphnia was not effected, but the growth (body length) of the parent animals:

NOEC (measured, TWA) = 0.457 mg/L

LOEC (measured, TWA) = 1.226 mg/L.

The results in this study are consistent with all validity criteria and the test is valid according to the guidelines of this study. No deviations from test guidelines or other incidents occurred during the course of the reported test which may have influenced the results.