Registration Dossier

Ecotoxicological information

Long-term toxicity to aquatic invertebrates

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

21day-reproduction toxicity in Daphnia: ErC50(21d) - >40mg/L; NOECr(21d) - = 20mg/L; LOECr(21d) - = 40mg/L

Key value for chemical safety assessment

EC10, LC10 or NOEC for freshwater invertebrates:
20 mg/L

Additional information

The 21-day-chronic toxicity of tetrahydromethylphthalic anhydride (MTHPA), of which 3 -MTHPA D4 is an isomer, to Daphnia Magna was studied under semi-static conditions in two Daphnia magna reproduction tests conducted in accordance with OECD test methods.

In a new key study of 2010 (Report No. 556.826.2254), daphnids were exposed at nominal concentrations of 1.25, 2.5, 5, 10, 20 and 40 mg/L. The NOEC was 20 mg/L and the LOEC was 40 mg/L.

An older study of 1997 (Report No. EDR96007) is regarded as of lower quality as the available study report does not give enough experimental details and analytical measurements are equivocal. In this study daphnids were exposed at nominal concentrations of 1.3, 4.1, 13, 41 and 130 mg/L. The 21 day LC50 for parenteral animals was >110 mg/L and the EC50 based on mortality/sublethal effects was 9.2 mg/L.

Both studies revealed comparable LC50 values (> 110 mg/L and > 40 mg/L) and, at high concentrations, a reduced number of juveniles. The weight of evidence from these studies justifies a NOEC of 20 mg/L for chronic Daphnia toxicity.