Trimethylenediamine

Long-term toxicity to fish

Description of key information

No experimental data available

ACR approach: NOEC > 1 mg/L

Relative species sensitivity: fish not most sensitive species, further testing on fish would not contribute to improve the current knowledge of the substance

Additional information

In Annex IX of Regulation (EC) No 1907/2006, it is laid down that long-term toxicity testing on fish shall be proposed by the registrant if the chemical safety assessment indicates the need to investigate further the effects on fish. According to Annex I of this regulation, the chemical safety assessment triggers further action when the substance or the preparation meets the criteria for classification as dangerous according to Directive 67/548/EEC or Directive 1999/45/EC or CLP Regulation (EC) No 1272/2008 or is assessed to be a PBT or vPvB.

The hazard assessment trimethylenediamine (TMEDA, CAS 109-76-2) reveals neither a need to classify the substance as dangerous to the environment, nor is it a PBT or vPvB substance, nor are there any further indications that the substance may be hazardous to the environment. Therefore, and for reasons of animal welfare, a long-term toxicity test in fish is not provided. 

The results from short-term toxicity tests on fish, aquatic invertebrates and algae demonstrate that aquatic invertebrates are the most sensitive trophic level tested. Therefore, it may be concluded that results from a long-term test in fish would not reveal a greater hazard than already determined by the available data. Therefore, and for reasons of animal welfare, a chronic test on fish is not provided. Long-term results are available for Daphnia magna (reproduction study, OECD 211) and algae (OECD 201) are available.

 

Relative species sensitivity:

According to the REACH guidance document R.7b chapter R.7.8.5.3, there are no further requirements for fish testing, if there is compelling evidence (e.g. using data generated with QSAR models) to suggest that the resulting fish value is likely to be at least a factor of about 10 less sensitive than invertebrates. In case of TMEDA (CAS 109-76-2) long-term data are available for aquatic invertebrates and algae (D. magna, 21-d NOEC ≥ 10 mg/L, nominal, analytically verified, BASF SE, 2014, report no. 51E0218/02E009;D. subspicatus, 72-h NOEC ≥ 500 mg/L, nominal, neutralized, BASF AG, 1990, report no. 2/w498/89). 

Regarding acute toxicity, aquatic invertebrates turned out to be the most sensitive aquatic trophic level with a 48-h EC50 of 27 mg/L (nominal,D. magna, EU method C.2; BASF AG, 1989, report no. 1/0498/2/89-0498/89). The short-term effect values for fish and algae are not definite. The 72-h ErC50 for algae was greater than 500 mg/L (nom., neutr.; BASF AG, 1990, report no. 2/w498/89). The LC50 for fish was determined to be > 464 mg/L (nom., neutr.; BASF AG, 1984, report no. 84/13). Therefore, the factor between aquatic invertebrates and fish is 17. This value is greater than the minimum requirement of the REACH guidance document R.7b, where fish should be at least a factor of about 10 less sensitive than aquatic invertebrates or algae.

To support the approach of relative species sensitivity, acute toxicity of TMEDA was calculated using the ECOSAR v1.11 model (EPI Suite v4.11). Both substances were within the applicability domain of the estimation model, applying to all calculations performed ECOSAR. The model defines TMEDA as an aliphatic amine within its aquatic toxicity scheme. Considering fish, the predicted LC50 for DMEA is a 96-h LC50 of 1437 mg/L. Considering daphnids, the model calculated a48-h LC50 of 120 mg/L. In case of algae, the model’s prediction for TMEDA is96-h EC50 = 200 mg/L. Summing up, the factor between the acute toxicity of fish and daphnids or algae is about 12 for TMEDA with fish being less sensitive.

Furthermore, chronic values (ChV) were estimated using ECOSAR v1.11. The calculated values indicate no concern for long-term toxicity to fish. The ChV for the target substance TMEDA was estimated to be 247 mg/L. Due to the limited number of chemicals in the training set (n ≤5), the uncertainty of the estimate has to be regarded as high, although the substances are within the model’s applicability domain. However, the chronic value of TMEDA is by a factor of 35 higher than the chronic value estimated for aquatic invertebrates (ChV = 7.0 mg/L).

Considering the possibility for the prediction of relative species sensitivities according to theREACH Guidance Document R.7b, chapter R.7.8.5.3,further testing on fish would not contribute to improve the current knowledge of the substance and/or its associated risk when released to the aquatic compartment.

This assessment is supported by the ACR approach of ECETOC (2003). Based on the 96 -h LC50 of > 464 mg/L for fish (nom., neutr.; BASF AG, 1984; report no. 84/13), the expected NOEC is > 1 mg/L. Therefore, chronic effects for fish are not to be expected.