Naphthalenesulfonic acid, di-C9-rich C8-10-branched alkyl derivs., barium salts

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

Samples for possible analysis were taken from all test concentrations and the control according to the
schedule below. In addition, glass wool containing udissolved residue was kept for possible analysis.
Frequency at t=0 h, t=24 h and t=98 h
Volume 2 ml
Storage Samples were stored in a freezer until analysis.

Vehicle:

no

Details on test solutions:

The standard test procedures required generation of test solutions, which should contain completely
dissolved test substance concentrations or stable and homogeneous mixtures or dispersions. The
testing of concentrations that disturb the test system should be prevented (e.g. film of the test
substance on the water surface).
The batch of di C8-C10, branched, C9 rich, alkylnaphthalene sulphonic acid (DNNSA) tested was
brown highly viscous liquid and a UVCB (treated as 100% pure) substance. Test substance was not
completely soluble in test medium at the loading rates initially prepared.
Preparation of test solutions started with individual loading rates ranged between 0.1 and 100 mg/l. A
2-day period of magnetic stirring was applied to obtain maximum dissolution of the substance in
medium. After a 1-hour settlement period the Water Accommodated Fractions (WAFs) were siphoned
di C8-C10, branched, C9 rich, alkylnaphthalene sulphonic acid (DNNSA) off through glass wool and used
as test concentrations. All test solutions, besides the highest WAF in the combined limit/range-finding test,
were clear and colourless. The WAF prepared at 100 mg/l in the combined limit/range-finding test was slightly hazy.

Test organisms (species):

Cyprinus carpio

Details on test organisms:

Species: Carp (Cyprinus carpio, Teleostei, Cyprinidae) Linnaeus,1758
Source: Zodiac, proefacc, "De Haar Vissen", Wageningen University
and Research Centre, The Netherlands.
Mean length:
Range-finding test: 3.0 ± 0.37 cm
Final test: 3.3 ± 0.2 cm
Mean weight:
Range-finding test: 0.82 ± 0.26 g
Final test: 0.86 ± 0.13 g
Characteristics F1 from a single parent-pair bred in UV-treated water.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

98 h

Post exposure observation period:

none

Hardness:

Adjusted ISO medium with a hardness of 180 mg CaCO3 per litre

Test temperature:

20.5 to 22.3

pH:

Day 0: 7.8 - 8
Day 4: 7.7 - 7.8

Dissolved oxygen:

Day 0: 8.5 - 9.1
Day 4: 6.7 - 7.2

Salinity:

NA

Nominal and measured concentrations:

Control and WAFs prepared at loading rates of 4.6, 10, 22, 46 and 100 mg/l.
Measured concentrations were 0.049, 0.28, 0.043, 0.0073 and 0.18 mg/L

Details on test conditions:

Test duration: 98 hours3
Test type: Static
Test vessels: 40 litres, all-glass, containing 15 litres of test solution
Test medium: Adjusted ISO medium with a hardness of 180 mg CaCO3 per litre and a pH of 7.7 ± 0.3.
Number of fish: 7 per concentration
Loading: 0.40 g fish/litre, i.e. 7 fish per 15 litres of test medium
Illumination: 16 hours photoperiod daily
Aeration: The test media were not aerated during the test.
Feeding: No feeding from 24 hours prior to the test and during the total test period
Introduction of fish: Within 1 hour after preparation of the test media from a holding tank with comparable water quality parameters and
pH and temperature differences between test and holding tank media of less than 0.5 unit and 0.5°C.

Reference substance (positive control):

yes

Remarks:

pentachlorophenol (PCP)

Duration:

98 h

Dose descriptor:

LC50

Effect conc.:

> 0.28 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

See tables.

Results with reference substance (positive control):

See Tables.

Reported statistics and error estimates:

LC50 could not attained.

Sublethal observations / clinical signs:

Incidence of mortality and total mortality during the final test

Test substance^1 Loading rate (mg/l)	Initial number of fish	Cumulativemortality					Total Mortality (%)
		2½h	24h	48h	72h	98h
control	7	0	0	0	0	0	0
4.6 (0.049)	7	0	0	0	1	1	14
10 (0.28)	7	0	0	0	0	0	0
22 (0.043)	7	0	0	0	0	0	0
46 (0.0073)	7	0	0	0	0	0	0
100 (0.18)	7	0	0	0	0	0	0

1.di C8-C10, branched, C9 rich, alkylnaphthalene sulphonic acid (DNNSA)

Average exposure concentration versus nominal concentration

Test substance^1 Loading rate (mg/l)	Measured concentration		Average exposure concentration (mg/l)
	t=0h (mg/l)	t= 98h (mg/l)
4.6	0.0443	0.0540	0.049
10	0.327	0.247	0.28
22	0.0484	0.0377	0.043
46	0.00878	0.00613	0.0073
100	0.180	0.186	0.18

1.di C8-C10, branched, C9 rich, alkylnaphthalene sulphonic acid (DNNSA)

Positive Control

Concentration PCP (mg/l) Nominal	Initial Number Of fish	Cumulative number of dead fish recorded at various time points after start of exposure					Total Mortality (%)
		2½h	24h	48h	72h	96h
0.10	5	0	0	0	0	0	0
0.22	5	0	1	1	1	1	20
0.46	5	0	5	5	5	5	100

 

Validity criteria fulfilled:

yes

Conclusions:

No clinical or lethal effects in carp at an average exposure concentration of 0.28 mg/l (NOEC) were observed. This is considered the highest attainable concentration in the test medium.

Executive summary:

A 96-Hour Acute Toxicity Study in Carp with di C8-C10, branched, C9 rich, alkylnaphthalene sulphonic acid (DNNSA) was conducted. The study procedure was based on the OECD guideline No. 203, 1992. The batch of di C8-C10, branched, C9 rich, alkylnaphthalene sulphonic acid (DNNSA) tested was brown highly viscous liquid and a UVCB (treated as 100% pure) substance. The test substance was not completely soluble in test medium at the loading rates initially prepared. A final test was performed based on results obtained in a range-finding test. Preparation of test solutions started with individual loading rates ranged between 0.1 and 100 mg/l. A 2-day period of magnetic stirring was applied to obtain maximum dissolution of the substance in medium. After a 1- hour settlement period the Water Accommodated Fractions (WAFs) were siphoned off through glass wool and used as test concentrations. All test solutions, besides the highest WAF in the range-finding test which was slightly hazy, were clear and colourless. Seven fish per group were exposed to a control and WAFs prepared at loading rates of 4.6, 10, 22, 46 and 100 mg/l. The total exposure period was 98 hours and samples for analytical confirmation of the exposure concentrations were taken at the start and at the end of the test. Analysis of the samples taken at the start of the final test showed measured concentrations being highly variable and not directly related to the applied loading rates. This was probably caused by the very low solubility of the substance in the medium and the fact that all concentrations were prepared separately. The concentration measured in the WAF prepared at 100 mg/l was 0.180 mg/l, which is close to the water solubility of the test substance (0.23 mg/l, WIL Research Europe project 498817). This concentration remained fairly stable. At the end of the test the actual concentrations in the remaining WAFs were between 70 and 122% of initial. Based on these results, the average exposure concentrations were calculated. The highest average concentration was measured in the WAF prepared at a loading rate of 10 mg/l and corresponded to 0.28 mg/l. The study met the acceptability criteria prescribed by the protocol and was considered valid. di C8-C10, branched, C9 rich, alkylnaphthalene sulphonic acid (DNNSA) induced no clinical or lethal effects in carp at an average exposure concentration of 0.28 mg/l (NOEC). The 98h-LC50 was beyond the range tested, i.e. exceeded the highest average exposure concentration of 0.28 mg/l. This was considered to correspond to the maximum soluble concentration in test medium. Therefore, under the test conditions, and given the solubility characteristics of the test material, neither the 98h-LC50 or a level causing any observable effect can be attained.

Description of key information

In a test on the acid analogue of the substance no mortality was observed at the highest attainable measured concentration of 0.28 mg/L. This is based on a nominal concentration of 10 mg/L.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

0.28 mg/L

Additional information

No studies on Barium bis(di C8-C10, branched, C9 rich, alkylnaphthalene sulphonate are available. For the analogue, di C8-C10, branched, C9 rich, alkylnaphthalene sulphonate, a study indicates that this substance is not toxic at the solubility level. A bridging study in daphnia confirms this approach. It is expected that the results found for the acid can be used for the salt in a read-across approach.

The LC50 is greater than 0.28 mg/L, the highest attainable concentration in the test medium.