TEA-Esterquat

Endpoint summary

Description of key information

Overall, the most sensitive organism in all available studies was fish. Thus, the lowest acute toxicity value is the 96 h LC50 of 1.91 mg/L obtained with Oncorhynchus mykiss. This value obtained with the source substance partially unsaturated TEA-Esterquat is also protective for the target substance C18 and C18 unsatd. TEA-Esterquat and will be used for chemical safety assessment.

Additional information

No experimental data are available for the target substance Esterification products of triglycerides C18 unsaturated with triethanolamine, dimethyl sulfate quaternized. However, reliable relevant data are available for the closely related source substances partially unsaturated TEA-Esterquat and fully saturated TEA-Esterquat. A justification for read-across is attached to iuclid section 13.

 

Toxicity to fish

In a 96-h acute toxicity study according to OECD Guideline 236, adopted July 26, 2013, embryonic stages of zebrafish (Danio rerio) were exposed to C18 and C18 unsatd. TEA-Esterquat at nominal concentrations of 0 (control) and 100 mg a.i./L under static conditions.

The test embryos were observed at test start and after approximately 24, 48, 72 and 96 hours test duration for hatching and apical observations (coagulation, somite formation, detachment of tail bud), whereas hatching and heart beat were only observed after 48, 72 and 96 hours.

4 days prior to the test all wells were preconditioned with the test water. Each well was filled with at least 2 mL freshly prepared test water with the respective concentration of the test item, reference item or negative control.

After 96 hours, all fish embryos survived in the control. In the only test item concentration of nominal 100 mg test item/L one embryo died after 96 hours. The death of one embryo in the only test item concentration is most probably not substance related since it is within the mortality range allowed to occur in the control (<10%).

Hatching success in the control was 100% and in the only test item concentration 95%. In the only test item concentration of nominal 100 mg test item/L all surviving embryos hatched. In the internal plate control of nominal 100 mg test item/L all embryos survived and 100% hatched after 96 hours.

The 96-h LC50 was >100 mg a.i./L based on analytically verified nominal concentrations.

 

In a 96-h acute toxicity study conducted according to OECD Guideline 203 (Fish, Acute Toxicity Test), rainbow trouts (Oncorhynchus mykiss) were exposed to partially unsaturated TEA-Esterquat at nominal concentrations of 0 (control), 1.0, 1.6, 2.56, 4.1, 6.55, 10.55 mg/l under semi static conditions. The mean measured concentrations were determined to be 59 % of nominal concentrations. The 96-h LC50 was 1.91 mg/L (based on mean measured concentrations). Sublethal effects such as difficulties with maintenance of balance and unusual behaviour (reduced activity and or orientation to bottom or surface of the test vessels) were observed within the first three hours in the highest test concentration.

Several supporting studies conducted with the source substance partially unsaturated TEA-Esterquat are available, which are described in section “Short-term toxicity to fish”.

 

In accordance with REACH Regulation, Annex IX, 9.1.6, column 2, long-term toxicity testing on fish does not need to be conducted. A test for long-term toxicity on fish is only required if the chemical safety assessment, according to Annex I, indicates the need to investigate further the effects on aquatic organisms. The choice of the appropriate test(s) depends on the results of the chemical safety assessment. As the registered substance does not need to be classified with regard to environmental effects, an exposure assessment is not required. The long-term exposure of aquatic organisms is unlikely as the substance is readily biodegradable. The ready biodegradability of the substance is proved in a number of tests conducted under different conditions (aerobic, anaerobic).

 

Toxicity to aquatic invertebrates

The 48 hr acute toxicity of partially unsaturated TEA-Esterquat to Daphnia magna according to EU Method C.2 (Acute Toxicity for Daphnia) was studied under static conditions.  Daphnids were exposed to control, and partially unsaturated TEA-Esterquat at nominal concentration of 1, 2.2, 4.84, 10.6, 23.4, 51.5, 113 mg test mat./L for 48 hr.  Mortality/immobilization was observed daily. The 48 hour EC50 was 2.23 mg a.i./L. The effect concentration was corrected for the analytical recovery of 93%

 

In accordance with REACH Regulation, Annex IX, 9.1.5 column 2, long-term toxicity testing on aquatic invertebrates does not need to be conducted. A test for long-term toxicity on aquatic invertebrates is only required if the chemical safety assessment, according to Annex I, indicates the need to investigate further the effects on aquatic organisms. The choice of the appropriate test(s) depends on the results of the chemical safety assessment. As the registration substance does not need to be classified with regard to environmental effects, an exposure assessment is not required. The long-term exposure of aquatic organisms is unlikely as the substance is readily biodegradable. The ready biodegradability of the substance is proven in a number of tests conducted under different conditions (aerobic, anaerobic).

 

Toxicity to algae

Acute value 72 h ErC50:

The lowest effect concentration of all valid tests is used. The test was made with fully saturated TEA-Esterquat which inhibited significantly the increase of biomass of the alga   Scenedesmus subspicatus in a study conducted according to OECD Guideline 201 (Alga, Growth Inhibition Test). The 72h-ErC50 was 1.52 mg/L.

 

Long-term value 72 h EC10:

As long-term effect value, instead of the NOEC, the EC10 is used. The current OECD guideline 201 as well as ECHA Guidance R.10, 2008 (Table R.10-1) as well as ECHA CLP Guidance, Nov. 2012 (4.1.3.1.1) recommend the use of the ErC10 instead of NOEC for classification as well as starting point for PNEC derivation.

For the long-term effect value 72 h ErC10, relevant studies are considered in a Weight of Evidence (WoE) approach: For the endpoint “Toxicity to aquatic algae and cyanobacteria”, there are five valid and comparable studies for the same taxonomic group available. For each study there is a full endpoint study record (EPR) in the dossier.

The 72 h ErC10 values for these studies are:

(a): 0.68 mg/L

(b): 1.53 mg/L

(c): 5.09 mg/L

(d): 1.26 mg/L

(e): 1.26 mg/L

The assessment of these comparable studies showed no study inherent reason for differences in results. All five studies were conducted following guidance OECD Guideline 201. All five EPR consider for effect calculation a concentration reduction factor to map the decrease of nominal concentration during the test duration. The values for the 72 h ErC10 range from 0.68 - 5.09 mg/L. For the WoE approach, the geometric mean of the five 72 h ErC10 values was calculated. According to this WoE approach, for this endpoint the 72 h ErC10 = 1.48 mg/L.

 

Toxicity to aquatic microorganisms

In a study with fully saturated TEA-Esterquat the acute bacterial toxicity towards Pseudomonas putida was determined under static conditions according to DIN 38412, part 27 (Inhibition of oxygen demand (Sauerstoffzehrungshemmtest) at test material concentrations of 10, 30, 100 mg test mat./L. The calculated effect concentrations after 30 minutes were as follows: EC0: 24.0 mg a.i./L, EC10: 29.6 mg a.i./L, EC50: 60 mg a.i./L.

Supporting data are available for partially unsaturated TEA-Esterquat, which are described in section “Toxicity to microorganisms”.

 

Conclusion 

Overall, the most sensitive organism in all available studies was fish. Thus, the lowest acute toxicity value is the 96 h LC50 of 1.91 mg/L obtained with Oncorhynchus mykiss. This value obtained with the source substance partially unsaturated TEA-Esterquat is also protective for the target substance and will be used as key value for chemical safety assessment.