Trimethyloctadecylammonium chloride

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1993

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

yes

Remarks:

chemical analyses were not performed

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

0.1 g/L stock solution was prepared by by adding 0.1 g to approximately 80 mL deionized water. The mixture was stirred for 30 minutes. Thereafter, deionised water was added up to a final volume of 1L. A clear homogeneous solution was obtained.
Test concentrations were prepared by dilution of the stock solution in Dutch Standard Water: control (0), 0.01, 0.018, 0.032, 0.058 and 0.105 mg/L nominal.

Test organisms (species):

Daphnia magna

Details on test organisms:

The test was performed with Daphnia magna (water fleas), of which a continuous culture is maintained at the Akzo Research Laboratories, Amhem. The animals used in the test were less than 24 hours old at the beginning of the test and were obtained from parent animals having an age of 24 weeks.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

approximately 12°dH

Test temperature:

19.9 - 20.4°C

pH:

8.1

Dissolved oxygen:

8.8 mg/L or 97%

Salinity:

Fresh water

Nominal and measured concentrations:

0.01, 0.018, 0.032, 0.058 and 0.105 mg/L nominal

Details on test conditions:

As test vessels were used 400 mL glass beakers containing 250 mL of test medium, which were covered with a glass plate. Each beaker contained 5 animals. In the definitive test per test concentration and control 20 animals were tested, divided into four batches of 5 animals each. The diluting water used for the preparation of the test concentrations was a synthetic water, Dutch Standard Water, having a pH of approximately 8.2 and a hardness of approximately 12"dH, containing per litre of deionized water:
100 mg of NaHC03
20 mg of KHCO,
200 mg of CaCI2.2H2O
180 mg of MgSO4.7H2O
The delonised water used had a conductivity of less than 5 p S/cm, a TOCcontent of less than 2 mg/L and contained no more than 0.01 mg copper/L.
The test was carried out in a temperature controlled room.
During the test the air temperature was continuously registered.
The light regime was 16 hours of ambient light per day, supplied by fluorescent tubes.
Measurements of pH and the oxygen concentrations were carried out at the beginning and at the end of the test in one random beaker per test concentration and control.

Reference substance (positive control):

no

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

ca. 0.04 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% CL 0.03 - 0.04 mg/L

Remarks:

equivalent to 0.037 mg a.i./L

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

ca. 0.018 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: equivalent to 0.016 mg a.i./L

Details on results:

At 0.01 mg/L, which was the lowest concentration tested, one animal was immobile after 48h. This is in the range of immobilization also allowed by the quality criteria for the control group. At the next higher concentration (0.018 mg/L) all animals survived and therefore, the NOEC after 48h amounts to 0.018 mg/L.
The lowest concentration producing 100% immobilization within 48h was 0.058 mg/L. The EC50 (48h) was calculated to be 0.04 mg/L with 95% confidence limits of 0.03 and 0.04 mg/L.

Reported statistics and error estimates:

The LC50, was calculated with a programme (Akzo programme SKBT, version 1.0). using both the binomial test method and the trimmed Spearman-Karber method.

Table 1. Mobility results

Immobility in the definitive test
Concentration		Number of mobile animals
of test substance		Test duration (h)
mg/L		0	24	48
Control
0.01	1	5	5	5
	2	5	5	5
	3	5	5	5
	4	5	5	5
	Total	20	20	20
0.018	1	5	5	5
	2	5	5	5
	3	5	5	5
	4	5	5	5
	Total	20	20	20
0.032	1	5	5	5
	2	5	5	5
	3	5	4	2
	4	5	5	2
	total	20	19	14
0.058	1	5	0	0
	2	5	1	0
	3	5	1	0
	4	5	1	0
	total	20	3	0
0.105	1	5	0	0
	2	5	0	0
	3	5	0	0
	4	5	0	0
	total	20	0	0

Conclusions:

Under the study conditions, the 48h EC50 and NOEC of the test substance were calculated to be 0.04 mg/L (equivalent to 0.037 mg a.i./L) and 0.018 mg/L (equivalent to 0.016 mg a.i./L), respectively.

Executive summary:

A study was conducted to determine the short-term toxicity of the test substance, C18 TMAC (91.6% active) to aquatic invertebrates according to OECD Guideline 202. Twenty Daphnia magna per group were exposed under static conditions to nominal concentrations of 0.01, 0.018, 0.032, 0.058 and 0.105 mg/L. Immobility was recoded at regular intervals. No analytical dose verification was conducted. At 0.01 mg/L, one animal was immobile after 48 h. This was in the range allowed by the quality criteria for the control group. At the next higher concentration of 0.018 mg/L, all animals survived. The 48 h NOEC was therefore established at 0.018 mg/L. The lowest concentration producing 100% immobilization was 0.058 mg/L. The 48 h EC50 was calculated to be 0.04 mg/L (equivalent to 0.037 mg a.i./L), with 95% confidence limits of 0.03 and 0.04 mg/L. Under the study conditions, the 48h EC50 and NOEC of the test substance were calculated to be 0.04 mg/L (equivalent to 0.037 mg a.i./L) and 0.018 mg/L (equivalent to 0.016 mg a.i./L), respectively (Mark, 1993).

Description of key information

The 48 h EC50 value of the test substance for toxicity aquatic invertebrates, which was determined at 0.037 mg a.i./L (nominal) has been considered further for hazard/risk assessment.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Effect concentration:

0.037 mg/L

Additional information

A study was conducted to determine the short-term toxicity of the test substance, C18 TMAC (91.6% active) to aquatic invertebrates according to OECD Guideline 202. Twenty Daphnia magna per group were exposed under static conditions to nominal concentrations of 0.01, 0.018, 0.032, 0.058 and 0.105 mg/L. Immobility was recoded at regular intervals. No analytical dose verification was conducted. At 0.01 mg/L, one animal was immobile after 48 h. This was in the range allowed by the quality criteria for the control group. At the next higher concentration of 0.018 mg/L, all animals survived. The 48 h NOEC was therefore established at 0.018 mg/L. The lowest concentration producing 100% immobilization was 0.058 mg/L. The 48 h EC50 was calculated to be 0.04 mg/L (equivalent to 0.037 mg a.i./L), with 95% confidence limits of 0.03 and 0.04 mg/L. Under the study conditions, the 48h EC50 and NOEC of the test substance were calculated to be 0.04 mg/L (equivalent to 0.037 mg a.i./L) and 0.018 mg/L (equivalent to 0.016 mg a.i./L), respectively (Mark, 1993).