Hydrocarbons, C7-C9, isoalkanes

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Type of information:

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

Adequacy of study:

key study

Study period:

12 March 2001 - 25 February 2004

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Guideline study with acceptable restrictions

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 203 (Fish, Acute Toxicity Test)

GLP compliance:

not specified

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: rainbow trout
- Strain: Lot 448, receipt date: 21-Feb-01
- Source: Pierce Associates Inc., West Buxton, Maine 04093
- Age at study initiation (mean and range, SD): 71 days (post-hatch)
- Feeding during test: no
- Food type: not fed for at least 24 h before and during study



ACCLIMATION
- Acclimation period and conditions: quarantined and observed for parasites and disease for 18 days and held in dilution water for 7 days before test at test temperature (11.3 - 12.8°C). Water was continuously aerated to provide a dissolved oxygen concentration of at least 80% of the air saturation value. Fish were not treated for disease or parasites before use in this study. Fish held under static conditions using biological and mechanical filtration, a 16 hour light / 8 hour dark photoperiod
- Type and amount of food: Finfish Starter - Zeigler Bros., Inc., Gardners, PA
- Health during acclimation (any mortality observed): no

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

RW water (Batch 58): 104 mg/L CaCO3

Test temperature:

13.9°C (sd = 0.1)

pH:

6.2 - 6.9 (old solution)
7.3 - 7.8 (new solution)

Dissolved oxygen:

6.4 - 7.1 mg/L (old solution)
8.4 - 9.0 mg/l (new solution)

Nominal and measured concentrations:

0, 1.3, and 13.4 mg/L (nominal)

Details on test conditions:

TEST SYSTEM
- Test vessel: glass aspirator bottles
- Type: closed, stoppered with foil covered neoprene stoppers
- Material, size, headspace, fill volume: appr. 4.5 L
- Renewal rate of test solution (frequency/flow rate): daily
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 2
- No. of vessels per vehicle/dilution water control (replicates): 2
- Biomass loading rate: 0.259 g/L


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water:
Dilution water: Reconstituted moderately hard water (Bacth 58). The dilution water was aerated prior to use

Individual treatment solutions (WAF) were prepared by adding appropriate amount of test substance to appr. 13 L of vehicle/dilution water in a 13.5 L glass aspirator bottles. Solutions were mixed for about 24 hours on a magnetic stirplate at room temperature. Mixture vessels were sealed with Teflon tape and aluminum foil covered neoprene stoppers. After mixing solution settled for 1 hour and cooled to test temperature before the WAF was removed through the outlet of the bottom of the bottles. "New" treatment and control solutions were prepared daily for renewals. For renewal bottles were drained until appr. 1000 mL remained and re-filled with appr. 3500 mL. New WAFs were prepared for each renewal at least 24 hours prior to their use in the test

- Total Organic Carbon: 0.2759 ppm (water quality analysis of RW Batch 58)
- Alkalinity: 56 mg/L as CaCO3 (water quality analysis of RW Batch 58)
- Conductivity: 304 µmhos (water quality analysis of RW Batch 58)


OTHER TEST CONDITIONS
- Lighting: continuous between 728 to 736 Lux. Monitored using a MicroVAX 3100-20E


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : mortality (daily), lethargy (daily)

TEST LOADINGS
- Spacing factor for test loadings: 10

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LL50

Effect conc.:

> 13.4 mg/L

Nominal / measured:

nominal

Conc. based on:

other: Water accomodated Fraction (WAF)

Basis for effect:

mortality (fish)

Details on results:

- Behavioural abnormalities: see table under "any information on results incl. tables"
- Other biological observations: see table under "any information on results incl. tables"
- Mortality of control: no mortality
- Other adverse effects control: none
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: none
- Effect concentrations exceeding solubility of substance in test medium: no

Sublethal observations / clinical signs:

No mortality or sub-lethal effects were observed in this study, therefore the LL50(96 h) is believed to be > 13.4 mg/L. This endpoint is based on the nominal mean loading rate of test substance to dilution medium

Tab.: In-Life Observations results summerized

	Loading rate (mg/L)	3 hours	Day 1	Day 2	Day 3	Day 4
Cumulative % Mortality	0 (Control)	0	0	0	0	0
% Sublethal Effects (Lethargic)		0	0	0	0	0
Cumulative % Mortality	1.3	0	0	0	0	0
% Sublethal Effects (Lethargic)		0	0	0	0	0
Cumulative % Mortality	13.4	0	0	0	0	0
% Sublethal Effects (Lethargic)		0	0	10	10	0

Validity criteria fulfilled:

yes

Conclusions:

The test substance hydrocarbons, C7, n-alkanes, isoalkanes, cyclics, exhibited a 96-hour LL50 value of >13.4 mg/L with rainbow trout (Oncorhynchus mykiss). The test substance did not exhibit mortality at a loading rate that exceeded its water solubility.

Executive summary:

The test substance hydrocarbons, C7, n-alkanes, isoalkanes, cyclics, exhibited a 96-hour LL50 value of >13.4 mg/L with rainbow trout (Oncorhynchus mykiss). The test substance did not exhibit mortality at a loading rate that exceeded its water solubility.

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

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

Adequacy of study:

key study

Study period:

1 November 1994 - 10 February 1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline 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 203 (Fish, Acute Toxicity Test)

GLP compliance:

yes

Remarks:

no certificate included

Analytical monitoring:

yes

Details on sampling:

Samples were removed from the "new" WAF solutions of each treatment on day 0, 1, 2, and 3 and from the "old" solutions of each treatment (composite of replicates) on day 1 and at termination for GC analysis.

Vehicle:

no

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: rainbow trout
- Strain: Lot 282
- Source: Thomas Fish Company, Anderson, CA
- Age at study initiation (mean and range, SD): appr. 3.5 weeks
- Length at study initiation (length definition, mean, range and SD): 4 - 6 cm
- Feeding during test
- Food type: not fed for appr. 22 h before and during study



ACCLIMATION
- Acclimation period: quarantined and observed for parasites and disease and were held in dilution water for at least 12 days before test, but not treated for diseases or parasites
- Acclimation conditions (same as test or not): 15°C ± 1°C for 7 days before the test
- Type and amount of food: Rangen Salmon Starter and Tetramin®flake fish food
- Health during acclimation (any mortality observed): no

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

222 - 226 mg/L CaCO3

Test temperature:

14.8°C (sd = 0.4)

pH:

7.8 - 8.3 (old solution)
7.9 - 8.7 (new solution)

Dissolved oxygen:

6.0 - 7.7 mg/L (old solution)
8.0 - 9.8 mg/L (new solution)

Nominal and measured concentrations:

0, 1.0, 2.3, 5.1, 11, and 25 mg/L (nominal)

Details on test conditions:

TEST SYSTEM
- Test vessel: glass aspirator bottles
- Type: closed, stoppered with foil covered neoprene stoppers
- Material, size, headspace, fill volume: appr. 4.5L, no headspace
- Renewal rate of test solution (frequency/flow rate): daily
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 5
- No. of vessels per vehicle control (replicates): 3
- Biomass loading rate: 0.23 g/L


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water:
Dilution water: Laboratory dilution water, Blend Water 3 (BW3), a mixture of carbon filtered well water and water dialyzed by reverse omosis

Individual treatment solutions (WAF) were prepared by adding appropriate amount of test substance to 17 L of BW3 in a 20L glass carboy. Solutions were mixed for about 24 hours on a magnetic stirplate at room temperature. Headspace appr. 2 - 2.5 L to provide optimum surface contact between test substance and dilution water. Vessel was stoppered with a neoprene stopper containing a glass siphon tube and a small piece of glass tubing to allow air flow needed for the siphon. Tubes covered with foil to prevent loss of volatiles. Carboys covered with an opaque to prevent photochemical degradation. After mixing solution settled for 1 hour and cooled to test temperature before the WAF was removed by glass siphon tubing from the bottom of the carboy. Three replicate chambers were prepared per treatment by comletely filling the test chambers with test solution (no headspace). "New" treatment and control solutions were prepared daily for renewals. Appr. 80% of the test solutions were renewed by each replacement with "new" solution.

- Total organic carbon: 0.310 and 0.776 ppm (monthly water quality analysis of BW3 from 26-Oct-94 and 16-Nov-94, respectively)
- Metals: Zinc 34 µg/L, Cyanide (total) < 0.025 mg/L, Phenolics (total) < 0.050 mg/L
- Pesticides: none detected
- Alkalinity: 64 and 63 mg/L as CaCO3 (water quality analysis of BW3 from 27-Oct-94 and 10-Nov-94)
- Conductivity: 410 and 400 µmhos (water quality analysis of BW3 from 27-Oct-94 and 10-Nov-94)


OTHER TEST CONDITIONS
- Photoperiod: diurnal, 16 hours light : 8 hours dark
- Light intensity: daylight intensity: 72.43 to 73.21 footcandles


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : mortality (daily), dark pigmentation (day 1, 2, 3, 4), lethargy (day 1, 2, 3, 4), erratic swimming (day 3, 4), labored breathing (day 3)

TEST LOADINGS
- Spacing factor for test loadings: ca. 2.2
- Range finding study
- Test loadings: 10, 100, 1000 mg/L and control
- Results used to determine the conditions for the definitive study: Nominal loading level in mg/L (percent mortality): 0 (0%), 10 (7%), 100 (100%), 1000 (100%)

Reference substance (positive control):

no

Duration:

72 h

Dose descriptor:

LL50

Effect conc.:

15.8 mg/L

Nominal / measured:

nominal

Conc. based on:

other: Water Accomodated Fraction (WAF)

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% CL: 13.0 - 19.7

Key result

Duration:

96 h

Dose descriptor:

LL50

Effect conc.:

11.4 mg/L

Nominal / measured:

nominal

Conc. based on:

other: Water Accomodated Fraction (WAF)

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% CL: 9.3 - 14.0

Duration:

96 h

Dose descriptor:

LL0

Effect conc.:

5.1 mg/L

Nominal / measured:

nominal

Conc. based on:

other: Water Accomodated Fraction (WAF)

Basis for effect:

other: survival

Details on results:

- Behavioural abnormalities: see table under "any information on results incl. tables"
- Other biological observations: see table under "any information on results incl. tables"
- Mortality of control: no mortality
- Other adverse effects control: none
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: none
- Effect concentrations exceeding solubility of substance in test medium: no

Sublethal observations / clinical signs:

The maximum loading concentration causing no mortality was 5.1 mg/L. The minimum loading concentration causing 100% mortality was 25 mg/L. The NOEL was 5.1 mg/L, calculated using a Dunett's Procedure of SAS, was based on survival. The 3, 24, and 48 -hour LL50 values could not be calculated due to an insufficient dose response.

Tab.: In-Life Observations

Nom. Conc. (mg/L)	Control day 0			1.0 (day 0)			2.3 (day 0)			5.1 (day 0)			11 (day 0)			25 (day 0)
Daily Mortality	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Cum. Mortality	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Normal	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5
Survival	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5
Nom. Conc. (mg/L)	Control day 1			1.0 (day 1)			2.3 (day 1)			5.1 (day 1)			11 (day 1)			25 (day 1)
Daily Mortality	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Cum. Mortality	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Dark Pigmentation	0	0	0	0	0	0	0	0	0	0	0	0	3	4	5	5	1	2
Lethargic	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	1	1
Normal	5	5	5	5	5	5	5	5	5	5	5	5	2	1	0	0	3	2
Survival	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5
Nom. Conc. (mg/L)	Control day 2			1.0 (day 2)			2.3 (day 2)			5.1 (day 2)			11 (day 2)			25 (day 2)
Daily Mortality	0	0	0	0	0	0	0	0	0	0	0	0	1	0	1	0	1	0
Cum. Mortality	0	0	0	0	0	0	0	0	0	0	0	0	1	0	1	0	1	0
Dark Pigmentation	0	0	0	0	0	0	0	0	0	0	0	0	3	3	2	3	2	0
Lethargic	0	0	0	0	0	0	0	0	0	0	0	0	1	2	1	0	0	1
Normal	5	5	5	5	5	5	5	5	5	5	5	5	0	0	1	2	2	4
Survival	5	5	5	5	5	5	5	5	5	5	5	5	4	5	4	5	4	5
Nom. Conc. (mg/L)	Control day 3			1.0 (day 3)			2.3 (day 3)			5.1 (day 3)			11 (day 3)			25 (day 3)
Daily Mortality	0	0	0	0	0	0	0	0	0	0	0	0	2	0	0	5	4	4
Cum. Mortality	0	0	0	0	0	0	0	0	0	0	0	0	3	0	1	5	5	4
Dark Pigmentation	0	0	0	0	0	0	0	0	0	0	0	0	2	4	2	0	0	0
Erratic Swimming	0	0	0	0	0	0	0	0	0	0	0	0	2	5	2	0	0	0
Labored breathing	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	1
Lethargic	0	0	0	0	0	0	0	0	0	0	0	0	0	0	2	0	0	1
Normal	5	5	5	5	5	5	5	5	5	5	5	5	0	0	0	0	0	0
Survival	5	5	5	5	5	5	5	5	5	5	5	5	2	5	4	0	0	1
Nom. Conc. (mg/L)	Control day 4			1.0 (day 4)			2.3 (day 4)			5.1 (day 4)			11 (day 4)			25 (day 4)
Daily Mortality	0	0	0	0	0	0	0	0	0	0	0	0	1	1	1	0	0	1
Cum. Mortality	0	0	0	0	0	0	0	0	0	0	0	0	4	1	2	5	5	5
Dark Pigmentation	0	0	0	0	0	0	0	0	0	0	0	0	0	3	2	-	-	0
Erratic Swimming	0	0	0	0	0	0	0	0	0	0	0	0	1	4	2	-	-	0
Lethargic	0	0	0	0	0	0	0	0	0	0	0	0	0	0	1	-	-	0
Normal	5	5	5	5	5	5	5	5	5	5	5	5	0	0	0	-	-	0
Survival	5	5	5	5	5	5	5	5	5	5	5	5	1	4	3	-	-	0

Validity criteria fulfilled:

yes

Conclusions:

The acute toxicity, as measured by mortality to rainbow trout (Oncorhynchus mykiss), was evaluated in freshwater. Under the conditions of this study, the test substance, hydrocarbons, C6-C7, n-alkanes, isoalkanes, cyclics, < 5% n-hexane, produced acute lethal toxicity to Oncorhynchus mykiss at 11.4 mg/L, based on nominal loading of the test substance in water.

Executive summary:

The acute toxicity, as measured by mortality to rainbow trout (Oncorhynchus mykiss), was evaluated in freshwater. Under the conditions of this study, the test substance, hydrocarbons, C6-C7, n-alkanes, isoalkanes, cyclics, < 5% hexane, produced acute lethal toxicity to Oncorhynchus mykiss at 11.4 mg/L, based on nominal loading of the test substance in water.

Reference 3

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Adopted according to OECD SIDS (public available peer reviewed source) and respective study summary. The original source is not available and has not been reviewed.

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

GLP compliance:

yes

Analytical monitoring:

yes

Vehicle:

no

Details on test solutions:

Individual treatment solutions were prepared by adding the test substance, via syringe, to 17 L of laboratory blend water in 20 L glass carboys that were sealed to minimize volatile loss of test material. The stock solutions were mixed for 24 hours with a vortex of <10% (1-2 cm vortex). Mixing was performed using a magnetic stir plate and teflon stir bar. After mixing, the solutions were allowed to settle for one hour and the Water Accommodated Fraction (WAF) was then siphoned from the bottom of the mixing vessel and added to the test vessels. Siphons were placed in the carboys prior to adding the test material.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: rainbow trout
- Source: Thomas Fish Co.
- Age at study initiation (mean and range, SD): approximately 5 weeks
- Length at study initiation (length definition, mean, range and SD): mean total length = 3.4 cm
- Weight at study initiation (mean and range, SD): mean wt. = 0.297 g

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Test temperature:

15.4 – 16.0°C

pH:

7.5 - 8.7 (7.6 to 8.7 for "new" solutions and 7.5 to 8.4 for "old" solutions)

Dissolved oxygen:

5.0 – 9.7 mg/L (8.0 to 9.7 mg/L for "new" solutions and 5.4 to 7.7 mg/L for "old" solutions)

Nominal and measured concentrations:

0, 0.9, 2.0, 10.0, 22.0, and 50.0 mg/L (nominal)
non-detected, 0.05, 0.12, 0.33, 0.36, 0.47 mg/L (measured)

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type: closed
- Material, size, headspace, fill volume: 4.0 L aspirator bottles containing 4.5L of solution sealed with no headspace
- Renewal rate of test solution (frequency/flow rate): Approximately 80% of each solution was renewed daily from a freshly prepared WAF.
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 3
- Biomass loading rate: 0.46 g fish/L

OTHER TEST CONDITIONS
- Photoperiod: 16 hrs light and 8 hrs dark
- Light intensity: 73 ft. candles

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LL50

Effect conc.:

18.4 mg/L

Nominal / measured:

nominal

Conc. based on:

other: Water Accomodated Fraction (WAF)

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

0.11 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

other: Water Accomodated Fraction (WAF)

Basis for effect:

mortality (fish)

Reported statistics and error estimates:

Probit procedure of SAS

Sublethal observations / clinical signs:

Tab.: Fish Total Mortality

Nominal Loading (mg/L)	Fish Total Mortality
	24h	48h	72h	96h
Control	0	1	1	1
0.9	0	2	2	0
2.0	0	2	2	1*
10.0	0	7	7	8
22.0	1	9	9	11
50.0	6	13*	21*	21*

* 2 non-test related mortalities

Validity criteria fulfilled:

not specified

Conclusions:

The acute toxicity, as measured by mortality to rainbow trout (Oncorhynchus mykiss), was evaluated in freshwater. Under the conditions of this study, hydrocarbons, C7-C9, isoalkanes produced acute lethal toxicity to Oncorhynchus mykiss at 18.4 mg/L, based on nominal loading of the test substance in water.

Executive summary:

The acute toxicity, as measured by mortality to rainbow trout (Oncorhynchus mykiss), was evaluated in freshwater. Under the conditions of this study, hydrocarbons, C7-C9, isoalkanes produced acute lethal toxicity to Oncorhynchus mykiss at 18.4 mg/L, based on nominal loading of the test substance in water.

Reference 4

Endpoint:

short-term toxicity to fish

Type of information:

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

Adequacy of study:

key study

Study period:

25 January - 2 August 1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP 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 203 (Fish, Acute Toxicity Test)

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

GLP compliance:

yes (incl. QA statement)

Remarks:

The Department of Health of the Government of the United Kingdom

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Water accomodated fractions (WAFs) were prepared. The test substance was added to test medium and stirred for 69-72 hrs. Vessels had minimal headspace to prevent volitilization. Contents of the vessels were then allowed to settle for 1-2 hrs. Aqueous phase was used for the test. Controls were subject to the same regime

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: Rainbow trout
- Source: Zeals Trout Farm, Zeals, Wiltshire
- Age at study initiation: fingerlings
- Length at study initiation (length definition, mean, range and SD): 4.1-4.9 cm (mean 4.4 cm)
- Weight at study initiation (mean and range, SD): 0.60-0.97 g (mean 0.73 g)


ACCLIMATION
- Acclimation period: > 9 days
- Acclimation conditions (same as test or not): yes
- Type and amount of food: Mainstream Trout Food No. 03, maintenance ration
- Health during acclimation (any mortality observed): mortality less than 5%

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96

Remarks on exposure duration:

h

Hardness:

262-284 CaCO3 mg/L

Test temperature:

16.0-16.6°C

pH:

7.1-7.7

Dissolved oxygen:

8.3-9.3 mg/L

Nominal and measured concentrations:

0, 1, 3, 10, 30, 100 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type: closed
- Material, size, headspace, fill volume: Aspirators filled with 11 L of WAF, no headspace, sealed with glass plates.
- Aeration: aspirator
- Renewal rate of test solution (frequency/flow rate): daily
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Laboratory mains supply, from bore holes in the North Downs, Mid Kent Water Company. Water is chlorinated to 0.1 mg/L. Water is then filtered to remove particles larger than 15 microns, then passed through activated carbon.
- Chlorine: < 0.02 mg/l Cl2
- Total organic carbon: 2.5 mg/L
- Alkalinity: 257 mg/L CaCO3
- Ca/mg ratio: 48:1
- Conductivity: 496 µs/cm
- Culture medium different from test medium: same
- Intervals of water quality measurement: 6 months

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Fish were observed at 3, 24, 48, 72, and 96 hrs after start of exposure.
Fish were observed for toxic symptoms including cough frequency, hyperventilation, color change, abnormal swimming, immobilization, and mortality.

TEST CONCENTRATIONS
- Range finding study
- Results used to determine the conditions for the definitive study: 48h LL50: 10 -100 mg/L

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LL50

Effect conc.:

3 - 10 mg/L

Nominal / measured:

nominal

Conc. based on:

other: Water Accomodated Fraction (WAF)

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

LL0

Effect conc.:

3 mg/L

Nominal / measured:

nominal

Conc. based on:

other: Water Accomodated Fraction (WAF)

Basis for effect:

mortality (fish)

Duration:

72 h

Dose descriptor:

LL50

Effect conc.:

10 - 30 mg/L

Nominal / measured:

nominal

Conc. based on:

other: Water Accomodated Fraction (WAF)

Basis for effect:

mortality (fish)

Duration:

72 h

Dose descriptor:

LL0

Effect conc.:

10 mg/L

Nominal / measured:

nominal

Conc. based on:

other: Water Accomodated Fraction (WAF)

Basis for effect:

mortality (fish)

Duration:

48 h

Dose descriptor:

LL50

Effect conc.:

10 - 30 mg/L

Nominal / measured:

nominal

Conc. based on:

other: Water Accomodated Fraction (WAF)

Basis for effect:

mortality (fish)

Duration:

48 h

Dose descriptor:

LL0

Effect conc.:

10 mg/L

Nominal / measured:

nominal

Conc. based on:

other: Water Accomodated Fraction (WAF)

Basis for effect:

mortality (fish)

Duration:

24 h

Dose descriptor:

LL50

Effect conc.:

30 - 100 mg/L

Nominal / measured:

nominal

Conc. based on:

other: Water Accomodated Fraction (WAF)

Basis for effect:

mortality (fish)

Duration:

24 h

Dose descriptor:

LL0

Effect conc.:

10 mg/L

Nominal / measured:

nominal

Conc. based on:

other: Water Accomodated Fraction (WAF)

Basis for effect:

mortality (fish)

Details on results:

- Behavioural abnormalities: At the 3 hr observation, some of the fish in the 3 and 10 mg/l groups, and all of the fish in the 30 and 100 mg/l groups showed signs of toxicity. One fish in the 100 mg/l group was immobilized, and another fish in this group had died. By the 24 hr observation, all fish in the 100 mg/l had died, as well as 3 of the fish in the 30 mg/l group. Some of the fish in the 3 and 10 mg/l group still showed signs of toxicity. By the 48 hr observation, all fish in the 30 mg/l group were dead, and some fish in the 10 mg/l group still showed signs of toxicity. The fish in the 3 mg/l group no longer showed signs of toxicity and showed no adverse effects for the remainder of the experiment. By the 72 hr observation, all fish in the 10 mg/l group showed signs of toxicity. By the 96 hr observation 4 of the fish in this group had died, while the remaining 3 showed signs of toxicity.
- Mortality of control: None
- Other adverse effects control: None

Reported statistics and error estimates:

Loading rates used to produce WAF that cause a 50% effect (LL50) were estimated by visual inspection of the data. This was considered more appropriate than an interpolative statistical analysis when considering toxicity data based on WAF of test substances that are mixtures containing components of low solubility.

Sublethal observations / clinical signs:

Table: Toxic symptoms exhibited by O. mykiss exposed to WAFs of SBP 100/140:

Loading rate used to produce WAF (mg/L)	No. of fish	Observation time and symptom classification
		3h					24h					48h					72h					96h
		a	b	c	d	e	a	b	c	d	e	a	b	c	d	e	a	b	c	d	e	a	b	c	d	e
Control	7	7					7					7					7					7
1	7	7					7					7					7					7
3	7	4	3				4	3				7					7					7
10	7	2	5				4	3				5	2					7					3			4
30	7		7					4			3					7					7					7
100	7		5		1	1					7					7					7					7

a) number of fish showing no symptoms

b) number of fish swimming normally but exhibiting toxic symptoms e.g. increased cough frequency, hyperventilation, colour change

c) number of fish swimming abnormally, e.g. on side or back

d) number of fish immobilised, e.g. lying on bottom of tank or floating at surface, but still alive

e) number of fish dead

Validity criteria fulfilled:

yes

Conclusions:

This study examined the short-term toxicity of hydrocarbons, C7-C9, n-alkanes, isoalkanes, cyclics to fish. Groups of 7 fish were exposed to loading rates of 0, 1, 3, 10, 30, or 100 mg/L. Fish were exposed for 96 -hrs with the test solution renewed daily. Fish were observed at 3, 24, 48, 72, and 96 hrs after start of exposure for signs of toxicity and mortality. No analytical monitoring was done as studies of closely related products has shown that the solubility of the test substance is likely to be less than the determination limit of the analytical equipment. All fish exposed to 30 mg/L or greater concentrations of test substance died. 4 fish in the 10 mg/L died, while the remaining 3 exhibited signs of toxicity. Though fish in the 3 mg/L group exhibited toxicity early in the experiment, by the end of the exposure period, they no longer showed signs of toxicity. The 96-hr LL50 for fish is 3-10 mg/L WAF.

Executive summary:

This study examined the short-term toxicity of hydrocarbons, C7 -C9, n-alkanes, isoalkanes, cyclics to fish. Groups of 7 fish were exposed to loading rates of 0, 1, 3, 10, 30, or 100 mg/L. Fish were exposed for 96 -hrs with the test solution renewed daily. Fish were observed at 3, 24, 48, 72, and 96 hrs after start of exposure for signs of toxicity and mortality. No analytical monitoring was done as studies of closely related products has shown that the solubility of the test substance is likely to be less than the determination limit of the analytical equipment. All fish exposed to 30 mg/L or greater concentrations of test substance died. 4 fish in the 10 mg/L died, while the remaining 3 exhibited signs of toxicity. Though fish in the 3 mg/L group exhibited toxicity early in the experiment, by the end of the exposure period, they no longer showed signs of toxicity. The 96-hr LL50 for fish is 3-10 mg/L WAF.

Description of key information

There is data available for this substance. Additionally, key and supporting data is available for structural analogues Hydrocarbons C7, n-alkanes, isoalkanes, cyclics; Hydrocarbons C6-C7, n-alkanes, isoalkanes, cyclics, < 5% n-hexane; and Hydrocarbons C7-C9, n-alkanes, isoalkanes, cyclics. 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:

The test substance hydrocarbons, C7, n-alkanes, isoalkanes, cyclics, exhibited a 96-hour LL50 value of >13.4 mg/L with rainbow trout (Oncorhynchus mykiss).

The test substance, hydrocarbons, C7-C9, isoalkanes produced acute lethal toxicity to Oncorhynchus mykiss at 18.4 mg/L, based on nominal loading of the test substance in water.

The test substance, hydrocarbons, C6-C7, n-alkanes, isoalkanes, cyclics, < 5% hexane, produced acute lethal toxicity to Oncorhynchus mykiss at 11.4 mg/L, based on nominal loading of the test substance in water.

The test substance, hydrocarbons, C7-C9, n-alkanes, isoalkanes, cyclics exhibited a 96-hour LL50 value for fish of 3-10 mg/L WAF.

Additional information

Four key study reports were available and input as endpoint records. These studies are summarised below.

 

The study from Exxon Mobil (2004) examined the short-term toxicity of the test substance hydrocarbons, C7, n-alkanes, isoalkanes, cyclics to Oncorhynchus mykiss in freshwater. The test substance did not exhibit mortality at a loading rate that exceeded its water solubility. The 96-h LL50 (mortality) for Oncorhynchus mykiss is therefore >13.4 mg/L.

 

The study from CEFIC (1995) examined the short-term toxicity of the test substance hydrocarbons, C7-C9, isoalkanes to Oncorhynchus mykiss in freshwater. The 96-h LL50 (mortality) for Oncorhynchus mykiss is 18.4 mg/L, based on nominal loading of the test substance in water.

 

The study from CEFIC (1995) examined the short-term toxicity of the test substance hydrocarbons, C6-C7, n-alkanes, isoalkanes, cyclics, < 5% hexane to Oncorhynchus mykiss in freshwater. The 96-h LL50 (mortality) for Oncorhynchus mykiss is 11.4 mg/L, based on nominal loading of the test substance in water.

 

The study from Shell (2004) examined the short-term toxicity of the test substance hydrocarbons, C7 -C9, n-alkanes, isoalkanes, cyclics to Oncorhynchus mykiss in freshwater. The test substance did not exhibit mortality at a loading rate that exceeded its water solubility. The 96-h LL50 (mortality) for Oncorhynchus mykiss is 3-10 mg/L WAF.