Triethylamine

Endpoint summary

Additional information

Beside acute toxicity data for three trophic levels (fish, aquatic invertebrates, and algae), also long-term toxicity data for the same trophic levels are available.

The toxicity of triethylamine towards the freshwater fish Oryzias latipes was investigated in accordance with OECD Guideline 203 (Ministry of the Environment in Japan. 1999a). As final result of this key study, a LC50(96h) value of 24 mg/L is reported.

As supporting study, Machado (1994) determined the acute toxicity towards Oncorhynchus mykiss according to the Test Guideline 797.1400 (US EPA, 1985) and the Standard Guide for Conducting Acute Toxicity Tests with Fishes, Macroinvertebrates, and Amphibians (ASTM, 1993). A NOEC (96 h) of 16 mg/L and a LC50 (96h) of 36 mg/L were determined.

Regarding toxicity to invertebrates, different effect concentrations are reported for two different species.

The mortality rate of Ceriodaphnia dubia was investigated by Collins (1994) which is regarded as key study. The toxicity test was performed according to the Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms (US EPA, 1991) and to the Standard Guide for Conducting Acute Toxicity Tests with Fishes, Macroinvertebrates, and Amphibians (ASTM, 1993). LC50 (48h) of 17 mg/L and NOAEC (48h) of 12 mg/L were given as results.

Further supporting information are given as well. Daphnia magna was exposed to triethylamine for a time period of 48 hours (Bringmann and Kuhn, 1959), resulting in an EC50 of 200 mg/L (basis of effect: avoidance of behaviour stimulus). The test procedure was similar to the one described by OECD Guideline 202.

The Ministry of the Environment in Japan (1999b) also investigated the acute toxicity towards the freshwater invertebrate Daphnia magna. The experimental conditions were in accordance with OECD Guideline 202. As final result, an EC50 (48h) value of 36 mg/L is reported.

Aquatic toxicity to algae was investigated by the Ministry of the Environment (1999d) using Pseudokirchnerella subcapitata as test organism (key study). The experimental conditions were in accordance with OECD Guideline 201. Based on the growth rate, the ErC50(72h) was determined as 8.0 mg/L while the NOEC(72h) amounts to 1.1 mg/L.

As supporting information, a read-across approach to tripropylamine (CAS 102-69-2) was performed. The toxicity of tripropylamine towards Desmodesmus subspicatus was investigated according to German industrial standard test guideline DIN 38423, part L9 (BASF AG, 1989). EC50 values based on growth rate as well as on biomass were reported as 24.82 mg/L and 15.14 mg/L, respectively. The toxic effects of the substance are probably due to an increase in pH at high concentrations of the test substance.

Another effect concentration for the green algae Scenedesmus quadricauda was determined by Bringmann and Kuhn (1959b) which is reported as

1 mg/L. Nevertheless, no standard method is described here and the effect concentration is not further specified.

Regarding chronic toxicity of the test substance to fish, two valid experimental results are available.

As key information, fish embryos of Salmo gairdneri (new name:Oncorhynchus mykiss) were used to investigate the chronic toxicity of triethylamine in a semi-static freshwater experiment (van Leeuwen et al., 1990). Based on mortality the following nominal results are reported: LC50 (60d) = 137 mg/L, EC50 (60d) = 130 mg/L, and LOEC (60d) > 100 mg/L, respectively. Taking the body length into account a LOEC (60d) of 100 mg/L is given. A LOEC (60d) of 3.2 mg/L is the result concerning weight of the test organisms as basis for effect.

As supporting information, the long-term toxicity of the test substance was determined by evaluating fertilized eggs of Danio rerio, which were observed for 7 days (van Leeuwen et al., 1990). The LC50 (7d) was determined as 180 mg/L. Based on the total embryotoxicity, the EC50 (7d) amounts to 53 mg/L while the LOEC (7d) is reported as 100 mg/L. Based on mortality, the LOEC (7d) amounts to 320 mg/L.

However, both studies (key and supporting study) are not used for the CSA since a NOEC value is not clearly specified.

Regarding chronic toxicity of the test substance to aquatic invertebrates, two valid experimental results are available.

With regard to the key study, The Ministry of the Environment in Japan (1999c) determined the chronic aquatic toxicity towards Daphnia magna according to OECD Guideline 211 resulting in a NOEC (21d) of 11 mg/L (based on reproduction). Referring to supporting information, the chronic toxicity to aquatic invertebrates was investigated according to US EPA Method 1002 (US EPA, 1989) by using Ceriodaphnia dubia as test organism (Collins, 1994). After 7 days of exposure, the following results were obtained: LOEC = 14 mg/L, NOEC = 7.1 mg/L, and MATC (Maximum Acceptable Toxicant Concentration) = 10 mg/L. This information is regarded as supporting.

A valid study concerning toxicity to microorganisms is available (BASF AG, 1989).

The key study according to the German industrial standard DIN 38412 (Part 8) was performed with special respect to sewage treatment plant organisms. Pseudomonas putida was exposed for 17 hours to non-neutralized and neutralized triethylamine. EC50 was found to be greater than 1000 mg/L, if the test substance is neutralized before. Tests with non-neutralized triethylamine gave the following results: EC10 = 71 mg/L, EC50 = 95 mg/L, and EC90 = 120 mg/L.