2,2',2''-nitrilotriethanol

Long-term toxicity to fish

Description of key information

No experimental data available

Chronic effects are not expected (NOEC > 1 mg/L)

Additional information

In Annex IX of Regulation (EC) No 1907/2006, it is laid down that chronic tests 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 of the substance 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.
Considering the possibility for the prediction of relative species sensitivities according to the REACH 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 conclusion is based on a factor of greater than 10 for fish to algae.
Therefore, and for reasons of animal welfare, a chronic test in fish is not provided.

Detailed justification for data waiving:

Long-term toxicity testing on fish (Annex IX, Section 9.1.6.1.)

Description of available data

Short-term toxicity data are available for all three trophic levels (fish, aquatic invertebrates and algae; Table 1).

The key study by Geiger et al. (1990) was performed according to an APHA method (1980) usingPimephales promelasas test species. Exposure conditions were flow-through. Test concentrations were analytically verified. The 96-h LC50 was determined to be 11800 mg/L (nom.) using pH-adjusted test solutions.

It is reasonable to conclude that TEA is with high probability acutely not harmful to fish after pH-adjustment (96-h LC50 > 100 mg/L).

No long-term toxicity test is available for fish. Based on the acute-to-chronic ratio (ACR) approach by ECETOC (2003), the NOEC is expected to be > 1 mg/L.

Acute toxicity to aquatic invertebrates was published by Warne et al. (1999).Ceriodaphnia cf. dubiawas the test species. The test concentrations were not analytically verified. The study was conducted according to ASTM Designation E1192 (1988; New South Wales Government Environment Protection Authority). Warne et al. (1999) determined a 48‑h EC50 of 610 mg/L.

It can be concluded that TEA is with high probability acutely not harmful to aquatic invertebrates (48-h EC50 > 100 mg/L).

Long-term effects on aquatic invertebrates were investigated in a reproduction study withDaphnia magnaas test species according to a method of the German Federal Environmental Agency which is similar to OECD TG 211. The test was designed as a semi-static procedure with closed vessels and an exposure period of 21 days. Test concentrations were analytically verified and deviated less than 20% from nominal concentrations. Parental mortality, number of offspring per animal and first appearance of offspring were determined. The most sensitive endpoint was parental mortality. The 21-d NOEC for parental mortality was determined to be 16 mg/L. The 21-d NOEC for reproduction was 125 mg/L, the NOEC for appearance of first offspring was 250 mg/L (Kuehn et al./UBA 1989; Kuehn et al., 1988).

Experimental results are available for the inhibition of growth of green algae based on the growth rate (Amann, 1989). The toxicity was studied according to German Industrial Standard DIN 38412, part 9. The test species wasDesmodesmus subspicatus. The test concentrations were not analytically verified. Test solutions were run in parallel with and without pH-adjustment. The 72-h ErC50 was 512 mg/L (pH-adjusted). The long-term effect value ErC10 was clearly greater than 1 mg/L (72‑h ErC10 = 26 mg/L). Without pH-adjustment, the effect values were lower: 72-h ErC50 = 216 mg/L; 72-h ErC10 = 7.9 mg/L.

It can be concluded that TEA is with high probability acutely not harmful to aquatic algae (EC50 > 100 mg/L).

 

Table 1: Aquatic toxicity data for TEA (CAS 102-71-6; key studies are emphasized by bold type)

Value	Remarks and reference
Fish: Short-term toxicity
96-h LC50 = 11800 mg/L (nom., analytically verified, pH-adjusted)	ASTM (1980), Pimephales promelas; Geiger et al.(1990)
Fish: Long-term toxicity
chronic NOEC > 1 mg/L (based on 96-h LC50 = 11800 mg/L, pH-adj.)	Acute-to-Chronic Ratio (ACR approach); ECETOC, 2003
Aquatic invertebrates: Short-term toxicity
48-h EC50 = 610 mg/L(nom., not pH-adj.)	ASTM Designation E1192;Ceriodaphnia cf. dubia,semi-static, test conc. not analytically verified; Warne et al. (1999)
Aquatic invertebrates: Long-term toxicity
21-d NOEC = 16 mg/L(meas., not pH-adj.)	similar to OECD TG 211,Daphnia magna,semi-static, test conc. analytically verified; Kuehn et al. (1988/1989), UBA (1989)
Algae: Toxicity (Growth inhibition)
72-h ErC50 = 512 mg/L(pH-adj.) 72-h ErC10 = 16 mg/L(pH-adj.) 72-h ErC50 = 216 mg/L(not pH-adj.) 72-h ErC10 = 7.9 mg/L(not pH-adj.)	German Industrial Standard DIN 38412, part 9,Desmodesmus subspicatus,static, test conc. not analytically verified; Amann (1989)

 

Based on the available experimental acute toxicity data, it can be concluded that algae are the most sensitive trophic level, followed by aquatic invertebrates. TEA is with high probability acutely not harmful to fish after pH-adjustment. It can be concluded that fish is the least sensitive trophic level.

With regard to CLP, TEA is not to be classified as acutely or chronically hazardous to the environment based on the available acute and chronic data. In accordance with Regulation (EC) No 1272/2008, Annex VI Table 3.2, the substance is not officially classified.

The substance is not to be classified as acutely hazardous to the aquatic environment, since the lowest acute effect value is >> 1 mg/L (algae: 72-h ErC50 = 512 mg/L; Amann, 1989).

Chronic data are available for daphnids and algae, therefore classification is based on the available chronic and acute toxicity data.

Chronic toxicity data are available for daphnids (21-d NOEC = 16 mg/L; Kuehn et al., 1988/1989) and algae (72-h ErC10 = 26 mg/L, Amann, 1989). According to the criteria outlined in Table 4.1.0(b)(ii) (Commission Regulation (EU) No 286/2011 amending Regulation (EC) No 1272/2008 for rapidly degradable substances), the substance is not to be classified as chronically hazardous to the aquatic environment.

Fish is the trophic level which is not covered by chronic data. Therefore, classification is based on the respective acute data; for fish, the 96-h LC50 was determined to be > 11800 mg/L (pH-adjusted; Geiger et al., 1990). The substance is readily biodegradable (see IUCLID Ch. 5.2.1); the log Kow is < 4 (log Kow = -2.3 at pH 7.1; see IUCLID Ch. 4.7). According to the criteria outlined in Table 4.1.0(b) (iii) (Commission Regulation (EU) No 286/2011 amending Regulation (EC) No 1272/2008), the substance is not to be classified as chronically hazardous to the aquatic environment.

 

Long-term toxicity to fish

Following a weight-of-evidence approach to justify the adaptation of the information requirements for fish of Annex IX without conducting a long-term toxicity test with fish according to Annex I and IX of Regulation (EC) No 1907/2006 and for reasons of animal welfare.

This weight-of-evidence approach includes the following methods:

- Acute-to-chronic ratio by ECETOC (2003)

- Relative species sensitivity (REACH Guidance R.7b,R.7.8.5.3)

 

Acute-to-chronic approach:

Acute-to-chronic ratios (ACR) have been developed by ECETOC as an alternative approach in the risk assessment to the empirically chosen assessment factors for deriving PNECs (ECETOC, 2003). Data for the calculation of ACR have been taken from the ECETOC Aquatic Toxicity database (EAT).

 

Table 2: Acute-to-chronic ratios and expected NOEC for TEA (CAS 102-71-6; short term toxicity on fish: 96-h LC50 = 11800 mg/L after pH-adjustment)

Source in ECETOC (2003)	Description	ACR (90%-ile)	Expected NOEC (mg/L): LC50 (11800 mg/L) / ACR
Table 40	All freshwater species (geometric mean)	71	> 1
Table 40	All freshwater fish (geometric mean)	57	> 1
Table 41	All freshwater species (individual species)	71.2	> 1
Table 41	All freshwater fish (individual species)	70.1	> 1
Table 42	Mode of action; freshwater & saltwater combined (individual species): narcotic	11.5	> 1

 

The expected NOECs for long-term effects on fish have been estimated by dividing the available experimental 96-h LC50 of > 100 mg/L (Table 1) with the ACRs 90%-ile for the different databases (Table 40, 41, 42 of ECETOC, 2003; Table 2). Five relevant ACRs have been considered for the estimation of the NOEC for fish long-term toxicity. Table 40 and 41 of the ECETOC (2003) document contain one ACR for all freshwater species and one ACR for all freshwater fish, either derived based on the geometric mean of all data or based on the individual species. The last ACR which was considered distinguishes the mode of action (Table 42 of ECETOC, 2003). TEA has been identified as a narcotic amine (acute aquatic toxicity classification of OASIS). The ACR (90%-ile) for narcotic substances is 11.5, which is similar to the factor of 10 for the relative species sensitivity of the REACH Guidance Document R.7b chapter R.7.8.5.3 (see following section). All five derived NOECs of this ACR approach by ECETOC are expected to be greater than 1 mg/L.

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 TEA, long-term data are available for aquatic invertebrates and algae (see Table 1), but not for fish.

Regarding acute toxicity, algae turned out to be the most sensitive aquatic organism with a 72-h ErC50 of 512 mg/L (pH-adjusted). Aquatic invertebrates have a similar sensitivity towards TEA (48-h EC50 = 610 mg/L). The 96-h LC50 for fish is 11800 mg/L for the test with pH-adjustment. The resulting factor between algae and fish is greater than 10 (factor = 19.3).

Considering the possibility for the prediction of relative species sensitivities according to the REACH 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.

 

Overall conclusion on long-term toxicity testing on fish

1.    Experimental acute toxicity data are available for all three trophic levels (fish, aquatic invertebrates and algae).

a.    Fish:         96-h LC50 = 11800 mg/L (meas., pH-adjusted)

b.   Aq. inv.:    48-h EC50 = 610 mg/L (nom., not pH-adjusted)

c.    Algae:       72-h ErC50 = 512 mg/L (nom., pH-adjusted)

2.    Experimental long-term toxicity data are available for aquatic invertebrates and algae:

a.    Aq. inv.:    21-d NOEC = 16 mg/L (meas., not pH-adjusted)

b.   Algae:       72-h EC10 = 26 mg/L (nom., pH-adjusted)

3.    According to a weight-of-evidence approach, it can be concluded that fish is not the most sensitive trophic level. This approach is based mainly on the following methods:

a.    Acute-to-chronic ratio by ECETOC (2003)

b.   Relative species sensitivity (REACH Guidance R.7b, R.7.8.5.3)

4.    Acute-to-chronic ratio (ACR; ECETOC, 2003):
The NOEC is expected to be > 1 mg/L based on five different databases (all freshwater species, all freshwater fish, all freshwater species with individual species, narcotic mode of action).

5.    Relative species sensitivity: Based on the available experimental acute toxicity data, the factor between the least sensitive species (algae, ErC50 = 512 mg/L) and fish (LC50 = 11800 mg/L) is 19.3. This value is > 10 as stated in section R.7.8.5.3 of the REACH Guidance Document R.7b.

6.    Based on the weight-of-evidence approach, it can be concluded that fish is the least sensitive trophic level. Reliable and valid long-term toxicity data are available for the more sensitive trophic levels aquatic invertebrates and algae. Therefore, further long-term toxicity testing on fish would not improve the current knowledge of TEA and/or its associated risk when released to the aquatic compartment.

7.    In addition, TEA is not a PBT nor a vPvB substance.

8.    Further, it should be taken into consideration that TEA is not officially classified and is also not to be classified as acutely or chronically hazardous to the environment according to CLP.

9.    The Registrant will update the waiver for the endpoint “Long-term toxicity testing on fish” (Annex IX, Section 9.1.6. of the REACH Regulation) as follows:
In Annex IX of Regulation (EC) No 1907/2006, it is laid down that chronic tests 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 of the substance 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.
Considering the possibility for the prediction of relative species sensitivities according to the REACH 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 conclusion is based on a factor of greater than 10 for fish to algae.
Therefore, and for reasons of animal welfare, a chronic test in fish is not provided.