Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

LC50 (96h) fish: 5.7 mg/L (Japanese Test Guideline,GLP)

Chronic Value (geometric mean of the LOEC and NOEC) for fish: 10.907 mg/L (Calculation with ECOSAR v1.11 (EPIWIN software by US-EPA)

EC50 (48h) daphnia: 15 mg/L measured (Japanese Test Guideline,GLP)

Chronic Value for daphnia: 6.235 mg/L (Calculation with ECOSAR v1.11 (EPIWIN software by US-EPA)

ErC50 (72h) algae: 0.553 mg/L measured,

NOECr (72h) algae: 0.202 mg/L measured (Japanese Test Guideline,GLP)

EC50(3h) microorganisms: 383 mg/L nominal (OECD 209)

Additional information

The acute toxicity of Benzalaceton towards fish was investigated under GLP according to relevant Japanese test guidelines (‘Testing Methods for New Chemical Substances’ of Pharmaceutical and Food Safety Bureau (PFSB), Ministry of Health, Labour and Welfare, as well as Environmental Policy Bureau-Ministry of the Environment (November 21, 2003 No. 1121002; November 13, 2003, No. 2; Manufacturing Industries Bureau, Ministry of Economy, Trade and Industry No. 031121002)) (Kureha, 2006). Himedaka (Oryzias latipes) was used as test organism and was exposed to the test substance for 96 hours. A LC50 (96h) of 5.7 mg/L was determined by the time-weighted mean measured concentrations of the test substance.

In addition, the acute toxicity to fish was investigated according to EU Method C.1 (which is equivalent to OECD Guideline 203) (Kanne, 1993). Danio rerio (Zebra fish) was used as test organism and was exposed for 96 hours to the test substance. A LC50 of 6.5 mg/L was determined by the geometric mean.

The environmental impact of wastewater, and thereby the acute toxicity of the test substance towards Danio rerio was investigated by Broroson et al. (1994). Based on the reported LC50(96h) value of 2100 mg/L (> 0.21 %), it is considered as disregarded study since the procedure is not described in detail.

The acute toxicity of Benzalaceton towards aquatic invertebrates was investigated under GLP according to relevant Japanese test guidelines also (‘ ‘Testing Methods for New Chemical Substances’ of Pharmaceutical and Food Safety Bureau (PFSB), Ministry of Health, Labour and Welfare, as well as Environmental Policy Bureau-Ministry of the Environment (November 21, 2003 No. 1121002; November 13, 2003, No. 2; Manufacturing Industries Bureau, Ministry of Economy, Trade and Industry No. 031121002)) (Kureha, 2006). Daphnia magna was used as test organism and was exposed to the test substance for 48 hours. An EC50 (48h) of 15 mg/L was determined by the geometric mean measured concentrations of the test substance.

The acute toxicity of methyl styryl keton (Benzalaceton) towards aquatic algae was investigated under GLP according to relevant Japanese test guidelines as well (‘Testing Methods for New Chemical Substances’ of Pharmaceutical and Food Safety Bureau (PFSB), Ministry of Health, Labour and Welfare, as well as Environmental Policy Bureau-Ministry of the Environment (November 21, 2003 No. 1121002; November 13, 2003, No. 2; Manufacturing Industries Bureau, Ministry of Economy, Trade and Industry No. 031121002)) (IDEA, 2010). The freshwater green algal species Pseudokirchneriella subcapitata was used as test organism and was exposed to test substance for 72 hours. An ErC50 (72h) of 0.553 mg/L and a NOECr (72h) of 0.202 mg/L was determined by the initial mean measured concentrations of the test substance.

The QSAR program ECOSAR v1.11 (EPIWIN v4.1 by US-EPA) was used to predict the acute and chronic toxicity towards fish, daphnids and algae using an extensive set of structure-activity relationships (SARs). An extensive set of structure – activity relationships (SARs) is utilized by the computer program, to predict the acute and chronic toxicity for three trophic levels for aquatic species. The mode of toxic action for most neutral organic chemicals is narcosis, and many chemical classes present toxicity to organisms via narcosis (i.e. ethers, alcohols, ketones). However, some organic chemical classes have been identified as having a more specific mode of toxicity. These are typically organics that are reactive and ionizable and that exhibit excess toxicity in addition to narcosis (i.e. acrylates, epoxides, anilines). The query substance belongs to the specific EOSAR class of Vinyl/Allyl Ketones. However, the SAR for neutral organics is more reliable due to the larger training set. In addition, the results with the neutral organic SAR is lower than with the specific Vinyl/Allyl Ketones SAR. This indicates that narcosis induced by the neutral organic is the primary toxic effect of benzalacetone. For short-term predictions L/EC50 values are predicted, whereas for long-term predictions only the so-called Chronic Value (ChV) is available. This value is defined as the geometric mean of the Lowest Observed Effect Concentration (LOEC) and the No Observed Effect Concentration (NOEC) and can classify the chemical only according to a low, moderate or high toxicity concern. Due to this, these values are not taken into account for the derivation of Predicted No Effect Concentrations (PNECs) for the aquatic compartment.

The following acute results were obtained for freshwater fish, daphnids and green algae: LC50(96h): 111.132 mg/L, LC50(48h): 63.32 mg/L and EC50(96h): 47.848 mg/L, respectively. The Chronic Values (ChVs) were predicted as 10.907 mg/L for fish, 6.235 mg/L for Daphnia and 12.627 mg/L for green algae, respectively, indicating a moderate toxicity for all three trophic levels.

Beside these supporting QSAR predictions, experimental data are also available for aquatic microorganisms in sewage treatment plants (STP). Following ISO 8192, which corresponds in most parts to OECD Guideline 209, an EC50 of 383 mg/L (nominal) was obtained concerning toxicity to microorganisms in waste water treatment plants (Kanne, 1993). A Microtox test with Photobacterium phosphoreum resulted in an EC50(15min) of 0.21 % (2100 mg/L), indicating a low toxicity.