α,α,α-trifluoro-p-toluidine

Endpoint summary

Additional information

Acute toxicity to invertebrates:

Two studies are available. One of them (RP Industrialisation, 1996), was quoted reliability 1 and was selected as key study. The 24 and 48 hours toxicity of p-TFMA to Daphnia magna was studied under static conditions (RP Industrialisation, 1996) and following the OECD 202 guideline.

Daphnids were exposed to control and test chemical at concentrations of 0 to 50% of the extracted solution.

Mortality and immobilization were observed.

The 48 hours EC 50 was 0.85 mg/L (mean measured concentration).

Based on the result of this study, p-TFMA should be classified very toxic for Daphnia magna in accordance with the EC classification criteria.

The other one (RP Industrialisation, 1992) was quoted reliability 2 and was selected as supporting study. the result reported was EC50 (24h): 8.1 mg/L and was similar to the value at 24 hours obtained in the previous study (9.1 mg/L).

Toxicity to algae:

One study with reliability 1 (Springbornsmithers, 2009) is available and was selected as key study.

In this 72 -hour toxicity study, the effects of p-TFMA on the growth of algae Pseudohirchneriella subcapitata were evaluated according to OECD 201 guideline.

The cultures of algae were exposed to p-TFMA (purity 98.2%) at concentrations of 0, 0.1, 0.32, 1, 3.2, 10, 32 and 100 mg test item/L, under static conditions.

At experimental completion (72 hours), cells exposed to all the treatment levels tested were observed to be normal. No change in the characteristics of the test solutions was observed throughout the duration of the test, apart from the highest test concentration, where at test termination a slight precipitation was observed on the edge of the test vessels.

The EC50 and EC10 based on growth rate after 72 hours were 8.48 and 2.28 mg/L respectively.

The NOEC based on growth rate and biomass after 72 hours was 0.61 mg/L.

Based on these results, p-TFMA could be considered as toxic for algae.

Toxicity to fish:

The strategy for acute toxicity tests with p-TFMA was adapted according to the European Chemicals Agency recommendations' (Guidance on information requirements, chapter R.7b) to limit tests on vertebrates. Hence the lowest LC50 result from the daphnia and algae tests was chosen as test concentration to perform a limit acute toxicity test with p- TFMA.

In this study (Springbornmithers, 2010), Oncorhynchus mykiss were exposed to paratrifluoromethylaniline at nominal and measured (geometric mean) concentrations of 1 and 0.93 mg/L respectively, under semi-static conditions.

No toxicity was observed after 96h at concentrations up to 0.93 mg/L.

The LC50 (96h) was then determined higher than 0.93 mg/L based on geometric mean measured concentration.

Validity criteria were fulfilled (≤ 10% mortality in the control(s); the dissolved oxygen air saturation values (ASV) > 60% throughout the study).

Then fish is confirmed to be much less sensitive than algae and invertebrates to p-TFMA.

This study is reliable without restrictions and satisfies the guideline requirements.

Long term toxicity:

As invertebrates were found to be the most sensitive species under acute toxicity tests, long term toxicity toward invertebrates was further investigated. The toxicity of p-TFMA to the reproduction of daphnids was studied under flow-through conditions. The test was performed under GLP and according to OECD 211 guideline (2008). The test concentrations were measured and were found to be within 80% of nominal concentrations. therefore nominal concentrations were used to determine the effect concentrations at the end of the test. The test had to be terminated after 20 days due to high mortality of adults in the control and the solvent control. Until the 19th day all parameters were still good and in line with the results in the range-finding test (performed during 21 days). Therefore even if the test cannot be considered as valid, the results give a good indication of the toxicity of the substance for the reproduction of daphnids. An EC10 -20d was determined at 0.36 mg/L (0.19 - 0.45 mg/L 95% confidence limit) based on the number of offspring per female. Other definitive tests have been conducted and are still ongoing to confirm this result. In the meantime this result is used to determine the PNECaquatic.