Hydrocarbons, C11-C12, isoalkanes, cyclics, <2% aromatics

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

January 1992

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: This robust summary has a reliability rating of 2 because only limited analyses accompanied the study. However, the study generally followed a standard guideline and GLP, and was conducted without deviations that would invalidate the study.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

equivalent or similar to guideline

Guideline:

EPA OPPTS 850.1020 (Gammarid Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

The water accommodated fraction prepared at 1000 mg/L and the control used on Day 2 of the study were analyzed. Both samples were analyzed upon preparation and after 24 hours.

Vehicle:

no

Details on test solutions:

Individual treatment solutions were prepared by adding accurately weighed test substance, to 0.5 L of natural seawater in erlenmeyer flasks. The stock solutions were thoroughly mixed for 24 hours and then the phases were allowed to separate for 24 hours. The Water Accommodated Fraction (WAF) was then drawn off the mixing vessel into the test vessels.

Test organisms (species):

other aquatic crustacea: Chaetogammarus marinus

Details on test organisms:

Test organisms were collected in the field in September, 1991 and cultured in the laboratory for 5 months prior to use in the test. They had a mean length of 3.3 mm. During the test, the test organisms were fed a few Artemia nauplii per day.

Test type:

semi-static

Water media type:

saltwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

None

Test temperature:

14.6 to 15.3 degrees C

pH:

7.4 to 7.9

Dissolved oxygen:

Greater than 5.9 mg/L

Salinity:

33.5‰ (3.4%)

Nominal and measured concentrations:

Nominal treatment levels were control, 10, 32, 100, 320, and 1000 mg/L. Measured concentrations for one treatment level and the control were determined for day 2 for the freshly prepared solutions and after 24 hours upon renewal. The 1000 mg/L treatment solution measured 0.096 mg/L when freshly prepared. The 24-hour results were not reported, but characterized as almost non detectable. Results of the control analyses were not reported.

Details on test conditions:

Test vessels were scintillation vials filled with about 20 ml of test solution. Ten replicates of each concentration and control were tested, each containing 1 test organism. The test organisms were gently transferred daily to vials with freshly prepared WAF. Lighting was 16 hrs light and 8 hrs dark.

Reference substance (positive control):

no

Duration:

24 h

Dose descriptor:

LL50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

48 h

Dose descriptor:

LL50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

72 h

Dose descriptor:

LL50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Key result

Duration:

96 h

Dose descriptor:

LL50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Key result

Duration:

96 h

Dose descriptor:

NOELR

Effect conc.:

1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Key result

Duration:

96 h

Dose descriptor:

NOELR

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: swimming behavior and food uptake

Details on results:

Mortality results for the definitive test:
Nominal Crustacean Total
Loading Mortality Mortality
(mg/L) (@ 24, 48, 72, 96 hrs)* (%)
Control 0, 0, 0, 0 0
10 0, 0, 0, 0 0
32 0, 0, 0, 0 0
100 0, 0, 0, 1 10
320 0, 0, 0, 0 0
1000 0, 0, 0, 0 0

* 10 organisms tested at each of the control and treatment treatment levels

Reported statistics and error estimates:

Statistical analyses were not conducted.

Validity criteria fulfilled:

yes

Conclusions:

The water accommodated fraction of the test substance did not produce a 50% effect (mortality) with Chaetogammarus marinus at loadings up to 1000 mg/L after a 96-hour exposure. Therefore, the 96-hour LL50 is reported as >1000 mg/L. There was no mortality at the 1000 mg/L loading level after 96 hours. Therefore, the 96-hour NOELR for mortality is reported as 1000 mg/L. There was also no mortality in the control.

Executive summary:

Water accommodated fractions (WAFs) of the test substance did not produce a 50% effect (mortality) with Chaetogammarus marinus after 96 hours at loadings up to 1000 mg/L. Therefore, the 96-hour LL50 is reported as >1000 mg/L. There was no mortality at the 320 and 1000 mg/L loading levels after 96 hours. However, effects on swimming and feeding behavior were observed in the 320 and 1000 mg/L loading levels. Therefore, the NOELR is reported as 1000 mg/L for mortality and 100 mg/L for the two non lethal effects. Although 10% mortality (1 organism) was observed in the 100 mg/L loading treatment, no mortality was observed in the 320 and 1000 mg/L loading treatments. Because no mortality occurred in the two higher loading levels, the mortality observed in the 100 mg/L was likely not caused by the test material. There was also no mortality in the control during the study. The control and treatment solutions were renewed every 24 hours. Analytical results showed that the treatment solution contained components of the test substance and that their combined concentration represented 0.096 mg/L of the test substance, based on one sample from a freshly prepared WAF for day 2. The 24-hour old sample from day two was reported as almost non detectable. The low analytical results are to be expected because of the very low water solubility of the components of the test substance. The reported 0.096 mg/L is likely to represent the highest achievable concentration of the test substance under the conditions of the test.

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

May 1994

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: This robust summary has a reliability rating of 1 because the study followed a standard guideline, followed GLP guidelines, and was conducted without deviations that would invalidate the study.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

The water accommodated fraction (WAF) of the test material was prepared by stirring the test material in the exposure solution for approximately 24 hours. The stirring was as vigorous as possible without causing an emulsion to form. After stirring, the WAF was allowed to settle for 1 hour before removing the aqueous phase for testing.

Test organisms (species):

Daphnia magna

Details on test organisms:

Organisms used in the test were from a laboratory culture were less than 24 hour old. The source of the culture was from Zeneca Brixham Laboratory from I.R.Ch.A., France.

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Post exposure observation period:

None

Hardness:

196 mg/L CaCO3

Test temperature:

18 to 20 degrees C

pH:

Within Guideline requirement

Dissolved oxygen:

8.9 to 9.2 mg/L

Nominal and measured concentrations:

The nominal loading rate was 1000 mg/L. A control was also tested.

Details on test conditions:

The study was conducted in closed test systems that were not renewed during the study. The test systems used were 150 ml glass Erlenmeyer flasks. The control and treatment level was evaluated in replicate test systems. Ten organisms, less than 24 hours old, were exposed in each of the control and treatment solution flasks and were not fed during the study.

Reference substance (positive control):

no

Duration:

24 h

Dose descriptor:

EL50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

24 h

Dose descriptor:

LL0

Effect conc.:

1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Key result

Duration:

48 h

Dose descriptor:

EL50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EL0

Effect conc.:

1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

There was no immobility reported in the treatment and control solutions at test termination.

Reported statistics and error estimates:

None

Validity criteria fulfilled:

yes

Conclusions:

The water accommodated fraction (WAF) of the test substance did not produce a 50% effect (immobility) with Daphnia magna at a loading of 1000 mg/L after a 48-hour exposure. Therefore, the 48-hour LL50 is reported as >1000 mg/L. There was no mortality at the 1000 mg/L loading level after 48 hours. Therefore, the 48-hour LL0 for mortality is reported as 1000 mg/L. There was also no mortality in the control.

Executive summary:

The water accommodated fraction (WAF) of the test substance did not produce a 50% effect (immobility) with Daphnia magna at a loading of 1000 mg/L after a 48-hour exposure. Therefore, the 48-hour LL50 is reported as >1000 mg/L. There was no mortality at the 1000 mg/L loading level after 48 hours. Therefore, the 48-hour LL0 for mortality is reported as 1000 mg/L. There was also no mortality in the control.

Description of key information

Freshwater:

Water accommodated fractions of hydrocarbons, C10-C12,isoalkanes, <2% aromatics, did not produce a 50% effect (immobility) with Daphnia magna at a loading of 1000 mg/L after a 48-hour exposure. Therefore, the 48-hour LL₅₀ is reported as >1000 mg/L. There was no mortality at the 1000 mg/L loading level after 48 hours. Therefore, the 48-hour LL₀ for mortality is reported as 1000 mg/L. There was also no mortality in the control.  These data are used as read-across data to hydrocarbons, C11-C12, isoalkanes, <2% aromatics.

Marine:

Water accommodated fractions of hydrocarbons, C10-C12,isoalkanes, <2% aromatics, did not produce a 50% effect (mortality) with Chaetogammarus marinus at loadings up to 1000 mg/L after a 96-hour exposure. Therefore, the 96-hour LL₅₀ is reported as >1000 mg/L. There was no mortality at the 1000 mg/L loading level after 96 hours. Therefore, the 96-hour NOELR for mortality is reported as 1000 mg/L. There was also no mortality in the control.  These data are used as read-across data to hydrocarbons, C11-C12, isoalkanes, <2% aromatics. These data are used as read-across data to hydrocarbons, C11-C12, isoalkanes, <2% aromatics.

Additional information

Freshwater: Water accommodated fractions of hydrocarbons, C10-C12,isoalkanes, <2% aromatics, did not produce a 50% effect (immobility) with Daphnia magna at a loading of 1000 mg/L after a 48-hour exposure. Therefore, the 48-hour LL₅₀ is reported as >1000 mg/L. There was no mortality at the 1000 mg/L loading level after 48 hours. Therefore, the 48-hour LL₀ for mortality is reported as 1000 mg/L. There was also no mortality in the control. These data are used as read-across data to hydrocarbons, C11-C12, isoalkanes, <2% aromatics.

Marine: Water accommodated fractions of hydrocarbons, C10-C12,isoalkanes, <2% aromatics, did not produce a 50% effect (mortality) with Chaetogammarus marinus at loadings up to 1000 mg/L after a 96-hour exposure. Therefore, the 96-hour LL₅₀ is reported as >1000 mg/L. There was no mortality at the 1000 mg/L loading level after 96 hours. Therefore, the 96-hour NOELR for mortality is reported as 1000 mg/L. There was also no mortality in the control. These data are used as read-across data to hydrocarbons, C11-C12, isoalkanes, <2% aromatics.