N,N-dimethylbutylamine

Endpoint summary

Additional information

Short-term toxicity

Fish:

QSAR models were used to estimate LC50 values because no study with the free base was located. The ECOSAR estimate for acute toxicity to fish was LC_{50(96 hr)}= 35 mg/L for the free base and approx. 200 mg/L for the neutral molecule. The estimate obtained with TEST was 64.3 mg/L. The former was selected as key and the latter as supporting study (GUBDH, 2012).

 

A valid GLP guideline study with the neutralized is available. The LC_{50(96 hr)}  212 mg/L, with a very steep dose-mortality curve (10% mortality at 180 mg/L, 90% mortality at 250 mg/L). The experimental LC_{50(96 hr)}-value is in good agreement with the ECOSAR estimate. Comparison with the estimate for the free base indicates that the latter is much more toxic, most probably as a result of the high pH-value. An increase of the pH is not to be expected at very low doses in the range of the PNEC.

 

Aquatic invertebrates:

The 48-h EC₅₀for acute effects on aquatic invertebrates is 29.7 mg/L with the free base (EU method C2;Daphnia magna, BASF AG, 1992).

 

Algae:

The 72-h E_rC50based on growth rate was 9 mg/L (free baseScenedesmus subspicatus(EU method C3, BASF AG, 1991).

 

Microorganisms:

The key study was conducted with Pseudomonas putida using a national method DIN 38412 Part 8 with a duration of 16 hours. The EC50 (16 hrs) ,based on biomass, was 480 mg/L with the free base. No growth inhibition was seen with the neutralized substance at 125 and 1000 mg/L (BASF AG, 1991).

Further, the respiration of activated industrial sludge was not affected, i.e. the oxygen was 5 to 10% increased in the presence of 400 or 800 mg DMBA/L compared to the controls (BASF AG, 1986).

 

Endpoint	Organism group	Species	Value [mg/L]	Reliability	Remarks	Source
96-h LC50	Fish	n.a.	35.0	2 key study	QSAR ECOSAR	GUBDH (2012)
96-h LC50	Fish	Fathead minnow	64.3	2 supp. study	QSAR TEST	GUBDH (2012)
48-h EC50	Aquatic invertebrates	Daphnia magna	29.7	1 key study	analytically verified concentrations; semi-static	BASF AG (1992)
72-h ECr50	Aquatic algae	Desmodesmus subspicatus(reported asScenedesmus subspicatus)	9	2 Weight of Evidence	Free base; inhibition based on growth rate	BASF AG (1991)
16-h EC50	Microorganisms	Pseudomonas putida	480	2 key study	inhibition based on biomass	BASF AG (1991)
16-h NOEC	Microorganisms	Industrial activated sludge	1000	Supporting study	Parameter: respiration	BASF AG (1986)

 

N, N-dimethylbutylamine is acutely toxic to fish, aquatic invertebrates, and algae. The toxicity of the neutralize molecule is much less pronounced.

Disturbances of wastewater treatment processes are not to be expected when N, N-dimethylbutylamine is released in appropriate amounts.

 

Long-term toxicity

 

Fish:

No valid data are available for the assessment of long-term toxicity to fish.

Aquatic invertebrates:

No long-term result study is available.

 

Algae:

No long-term result is available.