Fatty acids, C18-unsatd., reaction products with diethylenetriamine, acetates

Short-term toxicity to fish

Description of key information

Two acute toxicity studies on marine fish have been assessed. The results were determined to be:
- In a limit test  there was no mortality at a single test concentration of 0.23 mg/l (nominal concentration of whole test substance) and the 96h LC50 was assessed to be >0.23 mg/l.
- the LC50 values for the test substance was found to be 1.37 mg/l (active ingredient) after 96 hours. The NOEC value after 48 h was 0.103 mg/l based on active ingredient. 
Results from a acute toxicity study in freshwater fish have been read-across from a suitable structural analogue substance, Fatty acids, C18 unsaturated, reaction products with diethylenetriamine (also referred to a Tall oil diethylenetriamine imidazoline).
The study resulted in the following LC50 values
24 h LC50 = 0.31 mg/L; 48 h LC50 = 0.21 mg/L; 72 h LC50 = 0.20 mg/L; 96 h LC50 = 0.19 mg/L

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

0.19 mg/L

Marine water fish

Marine water fish

Effect concentration:

1.37 mg/L

Additional information

Marine Data:

Two marine fish studies have been conducted on the substance (Fatty acids, C18 unsaturated, reaction products with diethylenetriamine, acetate salts), the results of which are discussed below:

Study Reference: Kjonno O (2006):

Acute toxicity (96 h LC₅₀; semi-static test) of the test substance A01C2 acetate to the juvenile Sheepshead minnow (Cyprinodon variegatus) has been assessed in accordance with test guideline PARCOM 1995 Part B (modified OECD 203 Fish Acute Toxicity Test).

There was no mortality at the test single concentration of 0.23 mg/l (nominal concentration of whole test substance).

The 96 h LC50 was therefore assessed to be >0.23 mg/l (nominal concentration of whole test substance).

No analytical measurement of test material concentrations in samples was performed.

In the test, the control parameters, temperature, dissolved oxygen and salinity were within the recommended ranges.

Study Reference: Kuc W J (2006)

The objective of the study was to evaluate to acute toxicity of BL5060 to the sheepshead minnow, Cyprinodon variegatus, over a 96 -hour exposure period under static conditions; test solutions renewed at 48 hours. All values were based upon nominal concentrations of the toxicant in test water.

The test substance BL5060 was supplied as a 25.82% solution in water (i.e. activie ingredient 25.82%).

The study was conducted to procedures patterned after those outlined by the Paris Commission (PARCOM) in "Protocols on Methods for Testing of Chemicals Used in the Offshore Oil Industry Annex 1: Turbot/Sheepshead Minnow Juvenile Guidelines" and the (OECD) Guideline for Testing of Chemicals, "Fish Acute Toxicity Test" Part 203 as adopted by the Organisation for Economic Cooperation and Development on 17 July 1992.

Based on results from a range-finding study the following test concentrations were used in the definitive study: Control (0), 0.5, 1.0, 2.0, 4.0, 8.0 and 16.0 mg/l (nominal whole product).

The 96-hour LC50 and 95% confidence limits for BL5060 to the sheepshead minnow was determined to be 5.3 (4.6 - 6.1) mg/l (based on whole product). The 96-hour maximum concentration causing 0% mortality was determined to be 4.0 mg/l (based on whole product) (although one mortality was observed for the 1.0 mg/l concentration at 96 hours, both the 2.0 and 4.0 mg/l concentrations exhibited 100% survival); the minimum concentration causing 100% mortality was 8.0 mg/1 (based on whole product). The 96 hour No Effect Concentration (NOEC) is 4.0 mg/l. (based on whole product).

Behavioral abnormalities were observed in fish at the 8.0 mg/l (nominal whole product) test concentration.

The LC50 values for the test substance, based on active ingredient (i.e. 100% activity), was found to be 1.37 mg/l (active ingredient) after 96 hours. The NOEC value after 48 h was 0.103 mg/l based on active ingredient.

No analytical measurement of test material concentrations in samples was performed.

Key value for marine water fish:

Both studies are considered to be reliable. The Kuc W J (2006)study has been chosen for the key value for marine water fish however, as it was conducted using a number of different test concentrations rather than the single concentration tested in the

Kjonno O (2006) study. The study also tested greater test concentrations than the limit study at 0.23 mg/l. As mortality and other behavioural observations were seen in the Kuc W J (2006) study, whereas no mortality was observed in the Kjonno O (2006) study, it is considered appropriate to use this study as the key value for marine water fish,

However, the most sensitive marine species was determined to be algae. The 'geometric mean' algal result has therefore been used as the key result in the environmental assessment.

Freshwater data (Read-across data):

The results of a freshwater fish study on Fatty acids, C18 unsaturated, reaction products with diethylenetriamine (also referred to as Tall oil diethylenetriamine imidazoline) have been read-across to evaluate the toxicity to freshwater fish of Fatty acids, C18 unsaturated, reaction products with diethylenetriamine, acetate salts.

Study Reference: CECA (2009):

The acute toxicity (assessed by lethality) of the test item IMIDAZOLINE 4900 to Danio rerio (freshwater fish) for a duration of 96 hours was assessed according to the OECD guideline 203.

Fish were exposed to a range of concentrations of IMIDAZOLINE 4900 dissolved in dilution water. The definitive test was performed under semi-static conditions, with a renewal of test solutions every day. The measured toxic effect was the mortality after 24, 48, 72, and 96 hours.

The effective concentrations killing 50% of fish at 24h, 48, 72h, and 96h (LC50 -24h, 48h, 72h and 96h) were calculated by regression analysis using the Probit/log model. The results are presented in the following table.

Duration of exposure period (h)	*LC50 value, mg/L (95% CI)
24	0.31
48	0.21
72	0.20
96	0.19 (ND)

ND- Not determined

* results based on arithmetic mean measured concentration.

Analysis of test material concentrations in samples was performed. The concentrations of the substances were not maintained throughout the exposure period, so the results are based on an arithmetic mean measured concentration.

Discussion on read-across results:

The read-across results for the freshwater fish study are in line (same order of magnitude) with the marine results obtained for the acetate salts. The results indicate that freshwater species may be more sensitive to the test substance than marine species. However, it should also be taken into account that the freshwater result is based on measured (arithmetic mean) concentrations of test material in test samples, whereas the marine studies did not include analytical measurements of test material in samples, so the results are based on nominal concentrations.

In the freshwater study the concentrations of the test substance (Tall oil diethylenetriamine imidazoline) were not maintained throughout the exposure period, showing that test material was lost over the test period. It is considered likely that this would also be the case for the Fatty acids, C18 unsaturated, reaction products with diethylenetriamine, acetate salts. Therefore the reported LC50 values (based on nominal concentrations) in the marine studies conducted may be an over estimation of the LC50 based on potential loss of the substance over the test period.

It is considered that the results obtained from studies on Fatty acids, C18 unsaturated, reaction products with diethylenetriamine (Tall oil diethylenetriamine imidazoline) are suitable to read-across to and for use in the evaluation of Fatty acids, C18 unsaturated, reaction products with diethylenetriamine, acetate salts.