Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

Short-term ecotoxicological testing data for dimethyl cyclohexyl bisphenol (CAS# 2362-14-3) are available for all three primary trophic levels (i.e., fish, aquatic invertebrates and algae/aquatic plants) and also for microorganisms.

For fish, exposure of rainbow trout (Oncorhynchus mykiss) to DMBPC resulted in a 96-h LC50 of 528 µg a.i./L with a 95% confidence interval of 410 to 681 µg a.i./L. The 96-h No-Effect Concentration (NOEC) was 143 µg a.i./L.

Exposure of the aquatic invertebrate Daphnia magna to DMBPC resulted in 24- and 48- h EC50 values greater than 1084 µg a.i./L, the highest tested concentration and the approximate test substance water solubility limit. The 48- h NOEC is 1084 µg a.i./L.

For the green algae Selenastrum capricornutum, exposure to DMBPC for 96 h resulted in an EC50 that was greater than 1165 µg/L (the highest tested concentration and reported water solubility limit) when calculated using the number of cells/mL or the average specific growth rate, and 1141 µg/L when calculated using the area under the growth curve. The 96-h NOEC is 595 µg/L DMBPC when determined using the number of cells/mL, and 161 µg/L when determined using the area under the growth curve.

 

Exposure of activated sludge microorganisms to DMBPC for 20 to 30 d failed to reduce oxygen consumption in either municipal or industrial sludge, indicating a lack of toxic effects of DMBPC, resulting in a 30-day NOEC of 100 mg/L.

 

In accordance with Column 2 of Annex IX, long term studies are only needed if indicated based on the result of Chemical Safety Assessment. For this registration, the Chemical Safety Assessment does not indicate a need for such further studies. The substance is not manufactured or imported as such on the EEA market, but it is only available as a reacted monomer in an imported polymer with residual levels below 0.1 %; consequently the exposure and emissions to the environment are considered to be negligible. Therefore, no long term toxicity studies are necessary.