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Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

Short-term toxicity to fish

Reliable results obtained in studies conducted similar or according to guideline were available.

In a very well documented study, the acute toxicity to fish (Pimephales promelas) was investigated in a study conducted comparable to OECD guideline 203 'Fish, acute toxicity'under flow-through conditions and the actual concentrations were measured using GLC. In the duplicate tests 96 h LC50 and EC50 of 15.3 mg/L (test 1) and 14.2 mg/L (test 2) were obtained. Based on the similar results, a mean 96 h LC50 and EC50 value of 14.75 mg/L was calculated. These results were supported by a study conducted according to a national guideline which, however, showed minor deficiencies in documentation. In this 7 d toxicity study performed under flow through conditions with freshly hatched larvae from Pimephales promelas, a 96-h LC50=10.89 mg a.i./L (measured) was determined. In a peer-reviewed databank. the results of a further acute toxicity study conducted according to OECD Guideline 203 are reported (96 h LC50>10 mg test mat./L).

Long-term toxicity to fish

One reliable study is available dealing with the long-term toxicity of benzophenone to fish.

The 7– day chronic toxicity of benzophenone to early life stage of fathead minnows (Pimephales promelas) was investigated in a study conducted similar to OECD Guideline 212 (Fish, Short-term Toxicity Test on Embryo and Sac-Fry Stages) under flow through conditions. NOEC (7 d) values, based on mortality and sublethal effects (growth), were 5.86 mg a.i./L and 2.1mg a.i./L, respectively.

Short-term toxicity to aquatic invertebrates

A very well documented GLP study was perfomed on the acute toxicity to Daphnia magna acc. to OECD 202 and chosen to be the key study. Test duration was 48 h and immobilisation of the daphnids was assessed. The results obtained from this study reveal an EC50 of 6.784mg/L and a NOEC of 4.47mg/L.

Long-term toxicity to aquatic invertebrates

The documentation of the only available study is very limited, however, it is regarded as reliable as the information are taken from a peer-reviewed databank.

In a 21-d long-term reproduction study performed according to OECD Guideline 211 and using Daphnia magna as test organism, the 21-d EC50 and NOEC values were determined to be 1.1 and 0.20 mg mat./L, respectively.

Toxicity to aquatic algae and cyanobacteria

The documentation of the only available study is very limited, however, it is regarded as reliable as the information are taken from a peer-reviewed databank. In a 72 h toxicity study, the cultures of Pseudokirchenerella subcapitata were exposed to benzophenone in accordance with OECD Guideline 201. The 72 h EC50 and NOEC values based on growth rate were determined to be 3.5 and 1.0 mg/L, respectively.

Toxicity to microorganisms

A study acc. to OECD209 (2010) was performed to investigate the effects of Benzophenone on the respiration rate of activated sludge. The NOEC was set at 31.6 mg/L. The EC50 was determined to be at 787 mg/L.

Effects on gene expression (in vitro) and endocrine effects

In in vitro assays, benzophenone showed no or only minor effects.

Hayashi et al. (2006) found no estrogenic transcriptional activities of benzophenone using an in vitro assay with yeast cells expressing GAL4 fusion proteins with ER and its coactivator. Satoh et al. (2001) determined the binding affinities of some chemicals suspected of having endocrine disrupting effects for androgen and/or estrogen receptors (ADR, ERα) by a non-radioisotope receptor binding assay in vitro. The affinity of benzophenone was low for both receptors. Kerdivel et al. (2013) explored the differences between benzophenone and benzophenone derivates as well as their hydroxylated metabolites with respect to their effects on genes, tightly linked with estrogen-mediated proliferation (CXCL 12, amphiregulin genes and two classical estrogen-responsive genes) in vitro. While the authors reported significant differences in the efficiency to induce cell proliferation and endogenous target gene expressions, benzophenone was found to be completely inactive. Furthermore, the authors found some indications for the ED potency differences between the various benzophenones and their metabolites with respect to their mode of action.

Mussels

Canesi et al. (2007) investigated the effects of suspect endocrine disrupting compounds on several hemocyte parameters (lysosomal membrane stability (LMS), phagocytosis, lysozyme) of the marine bivalve Mytilus galloprovincialis Lam.. Lysosomal membrane stability which proved to be the most sensitive effect parameter was evaluated by the Neutral Red Retention time assay. The NOEC and LOEC (LMS) for benzophenone were determined to be 0.01 and 0.1 µM, respectively. The EC50 for benzophenone exposure was determined to be 8.535 µM (for comparison the results obtained for E2 (17ß-estradiol): NOEC, LOEC, EC50: 0.001, 0.005, 0.013 µM). The estradiol equivalency factor (EEF=EC50(E2)/EC50 (benzophenone) was calculated to 1.56 x 10E-3.

Invertebrates

Jubeaux et al. (2012) conducted laboratory tests to assess vitellogenin changes in male Gammarus fossarum after exposure to chemical stress. The males were exposed among others to benzophenone for 21 d. At the end of exposure and for each replicate 15 males (5 randomly collected in each replicate) were individually weighted, frozen in nitrogen liquid and stored at -80°C until vitellogenin measurement via HPLC/MS/MS. At the end of exposure, no mortality was observed, with survival rates >80%. Moreover, benzophenone did not induce vitellogenin production in males at concentrations ranging from 0.001 to 1000 µg/L.

Fish

In an in vivo bioassay, Brion et al. (2012) investigated the potential of natural or synthetic steroids or ubiquitous environmental contaminants to alter cyp19a1b-driven GFP (green fluorescent protein) expression in RGCs (radial glial cells) of developing zebrafish. Fertilized cyp19a1b-GFP transgenic zebrafish eggs were exposed to chemicals or to solvent control (DMSO; 0.01% v/v) under semi-static conditions from 0 to 5 days post-fertilization. At the end of exposure, the 5 days post-fertilization old zebrafish were processed for cyp19a1b GFP expression by polymerase chain reaction (PCR) or for fluorescence measurement by image analysis. For the test substance benzophenone, no induction of GFP expression was found in these experiments and thus indicating that benzophenone does not act as an estrogen mimic.

Shioda and Wakabayashi (2000) investigated the effects of endocrine disrupting chemicals (e.g. to benzophenone, nonylphenol and diethylhexyl phthalate) on the reproductivity of medaka. After two weeks of exposure of male medaka to e.g. benzophenone the male fish were moved to their original group and kept together with two females. The numbers of eggs spawned were counted every day for a week. Fertilization of eggs was examined and the numbers of hatchings were counted. In contrast to the results obtained with 17ß-estradiol, p-nonylphenol, 4 -t.-butylphenol and bisphenol A, benzophenone did not cause any decrease in the numbers of hatchings and eggs even in the highest concentration (10 µmol/L).