(3E)-1,7,7-trimethyl-3-(4-methylbenzylidene)bicyclo[2.2.1]heptan-2-one

Endpoint summary

Description of key information

A maximum BCF value of 801 L/kg was reported based on the peak concentration of test item in mussels during the uptake period.

Additional information

The bioaccumulation of 4-methylbenzylidene camphor was investigated in mussel (Mytilus galloprovincialis). Mussels were collected from the northwest Iberian coast and exposed to a single concentration of 1 µg/L test item in filtered seawater for 30 days (uptake period), followed by a 20 -day depuration period in untreated filtered seawater. A stock solution of the test item was prepared in dimethyl sulfoxide (DMSO), and the final concentration of DMSO in the test media was maintained below 0.1% (v/v). The experiment was conducted in 30 L glass tanks, each containing six mussels, under semi-static regime with test media renewal every 48 hours (except the first day, which was renewed at 24 hours). Samples of mussels and test media were taken for chemical analyses by LC-MS/MS after 0, 1, 2, 4, 8, 14, 22 and 30 days exposure, and after 2, 5, 9 and 20 days of depuration. The measured water concentrations were 0.87 µg/L at 30 mins, 0.61 µg/L at 24 hours and 0.42 µg/L at 48 hours. Measured test item concentrations in mussels were highly variable, therefore a bioaccumulation model could not be fit to the data. Taking the peak concentration of test item in mussels recorded at day 14, a maximum BCF value of 801 L/kg was obtained. This study is reliable with restrictions (Klimisch 2) as it was not conducted according to guideline, however the study is scientifically acceptable with minor limitations in experimental design and reporting (e.g. number of replicates).