Dibutylamine

Short-term toxicity to aquatic invertebrates

Description of key information

Dibutylamine is acutely harmful to aquatic invertebrates.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

58 mg/L

Additional information

To assess the short-term toxicity of dibutylamine (CAS 111 -92 -2) towards aquatic invertebrates, read-across was performed to the structurally similar substances diethylamine (CAS 109 -89 -7). Under supervision of the Japanese Ministry of the Environment a Daphnia magna immobilisation test according to OECD 202 was conducted under GLP and published in 2000. The daphnids were exposed for 48 hours under static conditions to nominal test concentrations of 0.79 to 15.0 mg/L diethylamine. In addition, in a supplemental test, test concentrations of 27.0 to 157.5 mg/L were tested. The test concentrations were analytically verified and deviated more than 20% from the nominal test concentrations. Therefore, measured geomean concentrations were used to assess the effect values. A 48 -h EC50 was determined to be 58 mg/L (95% CL: 49.9 - 68.1 mg/L, based on measured geomean concentrations; NITE 2000).

In addition, a study is available for dibutylamine (CAS 111 -92 -2) itself. The effects of dibutylamine on the acute toxicity to aquatic invertebrates, were investigated in a GLP-study according to ASTM guideline (1993), under semi-static conditions. As test organism, Ceriodaphnia dubia was used. The test concentrations were analytically verified and deviated less than 20% from the nominal test concentrations. The 48 -h EC50 value was determined to be 8.4 mg/L (based on mean measured concentrations), the 48 -h NOEC was 1.5 mg/L (Arkema, 1994. report no.: 94 -6 -5331).

In addition, a non-GLP study according to EEC Directive 79/831/EEC was conducted, using Daphnia magna as test organism. The test concentrations were not analytically verified. The test solutions showed initial pH values between 8.0 and 10.5. The recommended pH range for daphnids given in the OECD TG 202 was only kept in the control (0 mg/L) and in the treatments <= 12.5 mg/L, while the test solutions >= 25 mg/L showed initial pH values above 9. After 48 hours, the pH value shifted to acceptable levels in all treatments. However, an influence of the pH value on the toxicity of dibutylamine towards daphnids cannot be excluded.The 48 -h EC50 was determined to be 66.0 mg/L (95% CL: 55.1 - 79.0 mg/L; BASF AG, 1988, report no.: 1/0013/2/88 -0013/88). The results demonstrate that the aquatic invertebrate Ceriodaphnia dubia is considerably more sensitive to dibutylamine than Daphnia magna (factor 8). However, the study does not fulfill the requirements of the OECD 202 guideline, therefore it is not considered for the environmental risk assessment.

In conclusion, dibutylamine is acutely harmful to aquatic invertebrates.