Acetophenone

Endpoint summary

Additional information

Reliable results of acute toxicity testing are available for fish, invertebrates (Daphnia), algae, and microorganisms. Studies dealing with long-term toxicity are not available. In one study the acute toxicity to fish was investigated under flow-through conditions and with analytical monitoring. The study was conducted comparable to OECD guideline 203 'Fish, acute toxicity'. Acetophenone shows a low toxicity towards Pimephales promelas: 96 h LC50 and EC50=162 mg/L. Another study was conducted according to the national standard method US EPA (1975) with analytical monitoring. Based on the results, acetophenone shows a low acute toxicity towards Pimephales promelas (96 h LC50=161 -162 mg/L). A further study was conducted according to 'Standard practice for conducting acute toxicity tests with fishes, macroinvertebraten, and amphibians (ASTM, 1980) . Test substance concentration were measured daily via GC/FID, GC/ECD and/or HPLC. Based on the results, acetophenone can be regarded as substance with a low acute toxicity towards Pimephales promelas (96 h LC50=236 mg/L). A futher study was conducted comparable to US EPA (1975). The concentrations were tested under static conditions and not measured but the test vessels were covered with glass to reduce evaportation. Based on the results, acetophenone shows a low toxicity towards Pimephales promelas (96 h LC50=155 mg/L nominal). No data from guideline studies on chronic fish toxicity are available. According to Annex IX of Regulation (EC) No 1907/2006 chronic fish toxicity tests should be proposed if the chemical safety assessment indicates the need to investigate further the effects on fish. However, overall information is sufficient for risk assessment. Therefore, testing of on chronic fish toxicity is not regarded necessary. Furthermore, the substance is proven to be ready biodegradable. In the frame of determing body burden, also the 48 h LC50 of Daphnia magna exposed to acetophenone was determined. The concentration of radiolabeled acetophenone was measured using scintillation counting. The test vials were closed with screw caps. In the static test, a 48 h LC50=528 mg/L (4.4 mmol/L, nominal) was determined. No data from guideline studies on chronic invertebrate toxicity are available. According to Annex IX of Regulation (EC) No 1907/2006 tests should be proposed if the chemical safety assessment indicates the need to investigate further the effects on invertebrates. However, overall information is sufficient for risk assessment. Therefore, testing of on chronic invertebrate toxicity is not regarded necessary. Furthermore, the substance is proven to be readily biodegradable. In a toxicity study with Raphidocelis subcapitata conducted according to OECD guideline 201 (static conditions; stoppered BOD bottles; analytical monitoring of test substance concentration), the NOEC, 72 h ECb50, and 72 h-ECr50 were determined to be 24.8 mg/L, 40 mg/L (95% C.I.: 22.9-57.1 mg/L), and 86.4 mg/L (95% C.I.: 74.6-96.2 mg/L; effective), respectively. In two slightly modified guideline studies (OECD Guideline 209) acetophenone shows no inhibition of activated sludge respiration up to concentrations of 1000 mg/L (3 h IC50>1000 mg/L).