Tetradecane

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Study period:

24 Jun - 21 Nov 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

according to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: 0013861306
- Expiration date of the lot/batch: 15 Dec 2016
-Purity: 98.6%

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: The test substance is a mixture that is poorly soluble in water. Therefore the test solutions were prepared following general guidance provided in OECD 23 [Ref. 8] in order to achieve a water accommodated fraction (WAF) of the test substance using a liquid-liquid saturator technique. Each test solution was prepared separately by directly adding test substance to test medium. Glass aspirator bottles (2-L) with a bottom side-outlet attached to a stopcock were filled with 2-L test media. The necessary volume of the test substance was calculated from the density. Prior to use the test substance was homogenized by shaking the container. Then the test substance was pipetted carefully on the water surface. The bottle was closed and the solution was stirred on a magnetic plate for approximately 1 day. The stirring was slow enough (approx. 100 rpm) so that no vortex formed, preventing foaming or emulsification. After stirring, slight streaks were observed on the water surface in test concentrations ≥2.3 mg/L. The lower test concentrations appeared colorless and clear. The required volume of aqueous fraction (test solution) was drawn off for testing via the bottom of each bottle. All test solutions were visibly colorless and clear throughout each renewal period. The control medium is treated in the same way.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Strain/clone: 1820
- Justification for species other than prescribed by test guideline:
- Source: supplied by the Institut National de Recherche Chimique Appliquée, France, in 1978. From this date on this clone was cultured and bred continuously in the Ecotoxicology Laboratory of Experimental Toxicology and Ecology, BASF SE, Ludwigshafen, Germany.
- Age of parental stock (mean and range, SD): <24 h
- Feeding during test:
- Food type: live green algae Desmodesmus subspicatus
- Amount: The daphnids were fed a defined volume (≤153 μL) of the
concentrate (1310 - 1440 mg TOC/L) to reach the following amount of food: 0-3d: 0.1 mg TOC/L; 4-5d: 0.12 mg TOC/L; 6-7d: 0.14 mg TOC/L; 8-21d: 0.2 mg TOC/L
- Frequency: daily

ACCLIMATION
- Acclimation period: none
- Acclimation conditions (same as test or not): same
- Type and amount of food: same as during test
- Health during acclimation (any mortality observed): Only young from healthy cultures without signs of stress are used for testing.

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Hardness:

2.41 - 2.51 mmol/L

Test temperature:

20 °C

pH:

7.8 - 8.4

Dissolved oxygen:

8.2 - 9.0 mg/L

Nominal and measured concentrations:

Nominal: 0.52, 1.1, 2.3, 4.9 and 10.2 mg/L as loading rate WAF

Details on test conditions:

TEST SYSTEM
- Test vessel: 50 mL glass vessels containing 50 mL test solution
- Aeration: none
- Renewal rate of test solution (frequency/flow rate): daily renewal
- No. of organisms per vessel: 1
- No. of vessels per concentration (replicates): 10
- No. of vessels per control (replicates): 10

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: synthetic freshwater (Elendt M4)
- Total organic carbon: < 2 mg/L
- Alkalinity: 0.8 1.0 mmol/L
- Ca/mg ratio: 4:1
- Conductivity: 550 - 650 µS/cm
- Culture medium different from test medium: no
- Intervals of water quality measurement: Throughout the test, the appearance of the test solutions and dissolution behavior of the test substance was observed and recorded daily. The chemical and physical parameters of the test medium (total hardness, acid capacity, pH, conductivity and total organic carbon) were determined after aeration and prior to use in the test and were within acceptable ranges. Dissolved oxygen, pH and temperature were measured in the freshly prepared test solution and in the old test solution in replicate 1 of each test group for one interval per week. In addition, temperature was measured continuously during the whole exposure period in a separate vessel filled with water proximal to the test vessels. Hardness was measured in the freshly prepared test solution in an additional replicate of each concentration for one interval per week and in the old test solution from the combined replicates of each test group for one interval per week.

OTHER TEST CONDITIONS
- Photoperiod: 16h light/ 8h dark
- Light intensity: 699–756 lux at a wave length of 400–750 nm. The light intensity will not exceed 1000–1500 lux for cool white light (equivalent to 15–20 μE•m-2•s-1 according to the test guideline)

EFFECT PARAMETERS MEASURED: Parent mortality, abnormal effects, and numbers of live and dead offspring were assessed every day throughout the experiment.

- Range finding study: A preliminary range finding test was performed (experimental conduct in accordance with GLP but without a GLP status), with exposure over 17 days and daily solution renewal, at the following nominal concentrations: 0 (control), 1, 3, 10 mg/L. No significant effects were observed at 1 and 3 mg/L. At 10 mg/L there was a small, but not significant, reduction in offspring observed.

Reference substance (positive control):

yes

Remarks:

sodium chloride

Key result

Duration:

21 d

Dose descriptor:

NOELR

Effect conc.:

> 10.2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

(WAF)

Basis for effect:

reproduction

Details on results:

No additional adverse effects or abnormal behavior were observed in any of the other test groups.

Results with reference substance (positive control):

The EC50(48 h) of the reference substance sodium chloride (NaCl) was 5.36 g/L (experiment date: 14 Jun 2016, project number: 50E0789/12E060). This result is within the range of 3.88–7.22 g/L, which represents ±2 standard deviations from the published EC50(48 h) of 5.55 g/L [Ref. 6, 7] and indicates that the culture of Daphnia magna used in this study is responding normally to toxic stress.

There was no statistically significant effect on parent mortality (Fisher’s exact test) and reproduction per surviving and introduced parent (Wilcoxon test with Bonferroni-Holm adjustment) in any of the test groups.

Three mortalities were observed in the highest test group 5 (10.2 mg/L), two mortalities were observed in test group 4 (4.9 mg/L), one mortality each was observed in groups 3 (2.3 mg/L) and in the control group, although none of these were statistically significant according to Fisher’s test. In order to determine if these mortalities were inadvertent or substance related, the data were evaluated for a concentration response pattern using a step-down Cochran- Armitage trend test as indicated in the OECD 211 test guideline [Ref. 2]. The mortality data with test group 5 was significant; however, the data with test group ≤4 did not follow a concentration response pattern. Therefore the mortalities in group 3, group 4 and the control group is considered inadvertent. The inadvertent mortalities were excluded from the evaluation of reproduction per introduced parent, as recommended in the test guideline.

Reproduction per surviving and introduced parent was not significantly affected in anyt reatment group according to the Wilcoxon test. Although the reproduction per introduced parent in test group 5 is much less than the control, the standard deviation was very high due to three replicates that did not produce any offspring, while all other replicates produced offspring within the range of the control replicates.

Statistically significant effects on %immobile young were observed at ≥4.9 mg/L, however there was no effect on reproduction as living young in these test groups so the slight effect on immobile young is not considered toxicologically significant. On study day 17 a daphnid appeared to be pale and small in test group 2 (1.1 mg/L) in comparison to the animals in the control group. This appearance was transient as it was not observed anymore for the remainder of the test.

Validity criteria fulfilled:

yes

Conclusions:

The test substance is not harmful to aquatic invertebrates based on chronic exposure.

Executive summary:

The study was performed according to GLP and OECD guideline 211 using Daphnia magna as test organism (BASF 2017). Loading rate WAFS between 0.52 and 10.2 mg/L were tested. There was no statistically significant effect on parent mortality and reproduction per surviving and introduced parent in any of the test groups. Thus, the 21d-NOELr is determined to be >= 10.2 mg/L based on nominal loading rate.

Description of key information

There is no data available for this substance. However, key data is available for structural analogues Hydrocarbons, C11-C13 (odd numbered), n-alkanes, <2% aromatics and Hydrocarbons, C11-C13, isoalkanes, <2% aromatics The data is read across to this substance based on analogue read across and a discussion and report on the read across strategy is provided as an attachment in IUCLID Section 13. Key information is summarised below:

Hydrocarbons, C11-C13 (odd number), n-alkanes,<2% aromatics presented a 21-d NOELRs for Daphnia magna of ≥10.2mg/L (nominal loading rate), based on parent mortality and reproduction per surviving.

 

Hydrocarbons, C11-C13, isoalkanes, <2% aromatics presented a 21-d NOELRs for Daphnia magna of 1mg/L (nominal loading rate), based on effects on survival, reproduction, or length.

Additional information

Two studies are available investigating the long-term toxicity to aquatic invertebrates.

The study that tested Hydrocarbons, C11-C13 (odd numbered), n-alkanes, <2% aromatics to aquatic invertebrates was performed according to GLP and OECD guideline 211 using Daphnia magna as test organism (BASF, 2017). Loading rate WAFs between 0.52 and 10.2 mg/L were tested. There was no statistically significant effect on parent mortality and reproduction per surviving and introduced parent in any of the test groups. Thus, the 21 d-No Observed Effect Loading Rate (NOELR) is determined to be >= 10.2 mg/L based on nominal loading rate.

The study that tested Hydrocarbons, C11-C13, isoalkanes, <2% aromatics to aquatic invertebrates was performed according to GLP and OECD guideline 211 using Daphnia magna as test organism (ExxonMobil, 2001). The substance showed no effects on survival, reproduction, or length at a nominal loading of 1 mg/L. Therefore, the 21-Day NOELR is 1.0 mg/L for these endpoints based upon nominal loading levels.