Alkanes, C14-20

Long-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

fish, juvenile growth test

Type of information:

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

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Good experimental study although not GLP. No guideline available. Very long term trophic study (45 weeks exposure + 8 weeks depuration).

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

Reason / purpose for cross-reference:

reference to same study

Qualifier:

no guideline followed

Principles of method if other than guideline:

The fish are exposed to the substance through food for 7 to 10 months, then depurated for 2 months. Growth is recorded monthly.

GLP compliance:

no

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
No test surrogate material

Analytical monitoring:

not required

Details on sampling:

Not applicable (No analytical monitoring)

Vehicle:

no

Details on test solutions:

The substance was incorporated to the diet. The diet consisted of 36% herring fish meal / 33.5% wheat / 22.5% soybean meal / 3% soybean oil / 2% vitamin mix / 1% mineral mix /2% lignosulfite (binder). In the experimental diet, 1% of soybean oil was substituted by the same amount of substance.

The diets were pelleted (dry method) with a Templewood press in two pellet sizes: 2.5 mm (for trout 13-80 g weight) and 5 mm for the bigger sizes. Canthaxanthin (0.02%) was added to the 5 mm pellets.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: Rainbow trout
- Age at study initiation (mean and range, SD): 8 months
- Weight at study initiation (mean and range, SD): 13 g


FEEDING DURING TEST
- Food type: artificial; prepared at the laboratory
- Amount: satiation feeding
- Frequency: 4 times a day except the day before weighing

Test type:

other: Trophic exposure; flow-through tanks

Water media type:

freshwater

Limit test:

no

Total exposure duration:

45 wk

Post exposure observation period:

At the end of the exposure period, the remaining fish were divided into two groups: one group was fed at satiation 4 times a day on control diet, while the second group was maintained on total fast. Weight variations were followed for 8 weeks.

Hardness:

No data

Test temperature:

17 +/- 1 °C

pH:

no data

Dissolved oxygen:

no data

Salinity:

Not relevant (freshwater study)

Nominal and measured concentrations:

Nominal concentration in food: 10 g/kg

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: 7 m * 1.5 m * 0.4 m
- Water flow rate: 350 L/min
- No. of organisms per vessel: 800
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: 2.5 g/L


TEST MEDIUM / WATER PARAMETERS
- Tank water: spring water


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Mortality
- Weight : Lots of 100 trout, sampled using a table of random numbers were weighed weekly for the first month, then monthly
- Canthaxanthin determination in muscle, skin and remaing carcass at the pellet size change and at the end of the exposure
- Voluntary feed intake recorded weekly

Reference substance (positive control):

no

Duration:

45 wk

Dose descriptor:

other: effect concentration

Effect conc.:

> 10 other: g/kg diet

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

45 wk

Dose descriptor:

other: Decrease

Effect conc.:

10 other: g/kg diet

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

behaviour

Remarks:

voluntary food intake

Duration:

45 wk

Dose descriptor:

other: Decrease

Effect conc.:

10 other: g/kg diet

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: Reversible: increased growth rate during the depuration phase

Duration:

45 wk

Dose descriptor:

other: Decrease

Effect conc.:

10 other: g/kg diet

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: Canthaxanthin fixation

Duration:

45 wk

Dose descriptor:

other: Decrease

Effect conc.:

10 other: g/kg diet

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: Digestion of dry matter and lipids

Details on results:

- Fish weights, weight gains and feeding parameters: see Table 1
- Other biological observations: Canthaxanthin fixation: see Table 2; Digestion of dry matter and lipids: see Table 3
- Incidents in the course of the test which might have influenced the results: None

Depuration phase (see Table 4):
- General compensatory growth in fed test fish
- Reduced weight loss in starving test fish compared to control

Results with reference substance (positive control):

No reference substance

Reported statistics and error estimates:

Student's t-test

Table 1. Effect of 1% incorporation of pristane in the diet on appetite, growth and food utilisation in rainbow trout during the accumulation period.

 

Treatment	Initial mean weight (g)	Final mean weight (g)	Weekly mean body weight increase (g/wk)	Conversion factor (Feed/∆ W)	Feed intake (% BW/day)
Control	13.4	170	6.02	1.61	1.55
Pristane	13.7	137	2.74	2.69	1.40

∆ W: weight increase; BW: body weight

 

Table 2. Effect of 1% incorporation of pristane in the diet on canthaxanthin concentrations in different tissues of rainbow trout.

 

Treatment	Diet (µg/g)	Skin (µg/g FBW)	Muscle (µg/g FBW)	Remaining carcass (µg/g FBW)
Control	178	1.17	11.42	0.24
Pristane	179	1.18	3.64	0.37

FBW: Fresh body weight

 

 

Table 3. Digestion coefficients (%) calculated for dry matter and lipids in trout given diets containing pristane

 

Treatment	Dry matter	Lipids
Control	57.86 ± 0.34	90.47 ± 0.70
Pristane	55.76 ± 0.93*	82.73 ± 1.99*

* significantly different from control (p<0.001)

 

 

Table 4. Weight variation in rainbow trout starved or fed control diet for 8 weeks at the end of the exposure period.

 

Treatment	Fed				Starving
	Final weight (g)	% increase*	Weely weight increase* (g/wk)	Conversion factor	Final weight (g)	% decrease*	Weely weight decrease* (g/wk)
Control	236	38.8	8.3	3.07	146	14.1	3
Pristane	255	86.1	14.7	1.76	130	5.1	0.9

* since the end of exposure

 

Validity criteria fulfilled:

not applicable

Conclusions:

Very long term exposure (45 weeks) to 1% pristane in diet reduces fish appetite, fish growth, lipid digestibility and canthaxanthin fixation in rainbow trout. The effects are reversible.

Executive summary:

Pristane was incorporated into the diet (10 g/kg food) of rainbow trout to assess the effects of long-term exposure to saturated hydrocarbons. Feed intake was recorded daily and weight gain monthly.At the end of the accumulation time (45 weeks), canthaxanthin concentration was determined in the muscle, the skin and the remaining carcass. A general depressive effect of pristane was observed on both appetite and growth. The reduced growth rate could not be fully explained by the decrease in food consumption. Pristane reduced the lipid and dry matter digestibilities as well as canthaxanthin fixation in muscle.

During a 2 month depuration period, half the trout were fed a hydrocarbon-free diet while the other half starved. A general compensatory growth was observed in the fed fish. Correspondingly, for starving trout, the weight decrease was lower for the test group than in control.

Reference 2

Endpoint:

fish, juvenile growth test

Type of information:

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

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Good experimental study although not GLP. No guideline available. Very long term trophic study (41 weeks exposure + 8 weeks depuration).

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

Reason / purpose for cross-reference:

reference to same study

Qualifier:

no guideline followed

Principles of method if other than guideline:

The fish are exposed to the substance through food for 7 to 10 months, then depurated for 2 months. Growth is recorded monthly.

GLP compliance:

no

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
No test surrogate material

Analytical monitoring:

not required

Details on sampling:

Not applicable (No analytical monitoring)

Vehicle:

no

Details on test solutions:

The substance was incorporated to the diet. The diet consisted of 36% herring fish meal / 33.5% wheat / 22.5% soybean meal / 3% soybean oil / 2% vitamin mix / 1% mineral mix /2% lignosulfite (binder). In the experimental diet, 1% of soybean oil was substituted by the same amount of substance.

The diets were pelleted (dry method) with a Templewood press in two pellet sizes: 2.5 mm (for trout 13-80 g weight) and 5 mm for the bigger sizes. Canthaxanthin (0.02%) was added to the 5 mm pellets.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: Rainbow trout
- Strain: no data
- Source: no data
- Age at study initiation (mean and range, SD): 8 months
- Weight at study initiation (mean and range, SD): 13 g
- Method of breeding: no data


FEEDING DURING TEST
- Food type: artificial; prepared at the laboratory
- Amount: satiation feeding
- Frequency: 4 times a day except the day before weighing

Test type:

other: Trophic exposure; flow-through tanks

Water media type:

freshwater

Limit test:

no

Total exposure duration:

41 wk

Post exposure observation period:

At the end of the exposure period, the remaining fish were divided into two groups: one group was fed at satiation 4 times a day on control diet, while the second group was maintained on total fast. Weight variations were followed for 8 weeks.

Hardness:

No data

Test temperature:

17 +/- 1 °C

pH:

no data

Dissolved oxygen:

no data

Salinity:

Not relevant (freshwater study)

Nominal and measured concentrations:

Nominal concentration in food: 10 g/kg

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type: open
- Material, size, headspace, fill volume: 7 m * 1.5 m * 0.4 m
- Water flow rate: 350 L/min
- No. of organisms per vessel: 800
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: 2.5 g/L


TEST MEDIUM / WATER PARAMETERS
- Tank water: spring water


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Mortality
- Weight : Lots of 100 trout, sampled using a table of random numbers were weighed weekly for the first month, then monthly
- Canthaxanthin determination in muscle, skin and remaing carcass at the pellet size change and at the end of the exposure
- Voluntary feed intake recorded weekly

Reference substance (positive control):

no

Duration:

41 wk

Dose descriptor:

NOEC

Effect conc.:

10 other: g/kg diet

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

41 wk

Dose descriptor:

other: Decrease

Effect conc.:

10 other: g/kg diet

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

behaviour

Remarks:

voluntary food intake

Duration:

41 wk

Dose descriptor:

other: Decrease

Effect conc.:

10 other: g/kg diet

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: Reversible: increased growth rate during the depuration phase

Duration:

41 wk

Dose descriptor:

other: Decrease

Effect conc.:

10 other: g/kg diet

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: Canthaxanthin fixation

Duration:

41 wk

Dose descriptor:

other: Decrease

Effect conc.:

10 other: g/kg diet

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: Digestion of dry matter and lipids

Details on results:

- Fish weights, weight gains and feeding parameters: see Table 1
- Other biological observations: Canthaxanthin fixation: see Table 2; Digestion of dry matter and lipids: see Table 3
- Incidents in the course of the test which might have influenced the results: None

Depuration phase (see Table 4):
- General compensatory growth in fed test fish
- Reduced weight loss in starving test fish compared to control

Results with reference substance (positive control):

No reference substance

Reported statistics and error estimates:

Student's t-test

Table 1. Effect of 1% incorporation of dodecylcyclohexane in the diet on appetite, growth and food utilisation in rainbow trout during the accumulation period.

 

Treatment	Initial mean weight (g)	Final mean weight (g)	Duration of accumulation experiment (weeks)	Weekly mean body weight increase (g/wk)	Conversion factor (Feed/∆ W)	Feed intake (% BW/day)
Control	13.4	170	26	6.02	1.61	1.55
Dodecyl-cyclohexane	13.6	169	41	3.79	2.14	1.42

∆ W: weight increase; BW: body weight

 

Table 2. Effect of 1% incorporation of dodecylcyclohexane in the diet on canthaxanthin concentrations in different tissues of rainbow trout.

 

Treatment	Diet (µg/g)	Skin (µg/g FBW)	Muscle (µg/g FBW)	Remaining carcass (µg/g FBW)
Control	178	1.17	11.42	0.24
Dodecyl-cyclohexane	164	1.22	4.66	1.08

FBW: Fresh body weight

 

 

Table 3. Digestion coefficients (%) calculated for dry matter and lipids in trout given diets containing dodecylcyclohexane

 

Treatment	Dry matter	Lipids
Control	57.86 ± 0.34	90.47 ± 0.70
Dodecylcyclohexane	54.68 ± 1.16*	86.97 ± 0.78*

* significantly different from control (p<0.001)

 

 

Table 4. Weight variation in rainbow trout starved or fed control diet for 8 weeks at the end of the exposure period.

 

Treatment	Fed				Starving
	Final weight (g)	% increase*	Weely weight increase* (g/wk)	Conversion factor	Final weight (g)	% decrease*	Weely weight decrease* (g/wk)
Control	236	38.8	8.3	3.07	146	14.1	3
Dodecyl-cyclohexane	265	56.8	12	3.09	151	10.7	2.2

* since the end of exposure

Validity criteria fulfilled:

not applicable

Conclusions:

Very long term exposure (41 weeks) to 1% dodecylcyclohexane in diet reduces fish appetite, fish growth, lipid digestibility and canthaxanthin fixation in rainbow trout. The effects are reversible.

Executive summary:

Dodecylcyclohexane was incorporated into the diet (10 g/kg food) of rainbow trout to assess the effects of long-term exposure to saturated hydrocarbons. Feed intake was recorded daily and weight gain monthly.At the end of the accumulation time (41 weeks), canthaxanthin concentration was determined in the muscle, the skin and the remaining carcass. A general depressive effect of dodecylcyclohexane was observed on both appetite and growth. The reduced growth rate could not be fully explained by the decrease in food consumption. Dodecylcyclohexane reduced the lipid and dry matter digestibilities as well as canthaxanthin fixation in muscle.

During a 2 month depuration period, half the trout were fed a hydrocarbon-free diet while the other half starved. A general compensatory growth was observed in the fed fish. Correspondingly, for starving trout, the weight decrease was lower for the test group than in control.

Reference 3

Endpoint:

fish, juvenile growth test

Type of information:

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

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Good experimental study although not GLP. No guideline available. Very long term trophic study (31 weeks exposure + 8 weeks depuration).

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

Reason / purpose for cross-reference:

reference to same study

Qualifier:

no guideline followed

Principles of method if other than guideline:

The fish are exposed to the substance through food for 7 to 10 months, then depurated for 2 months. Growth is recorded monthly.

GLP compliance:

no

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
No test surrogate material

Analytical monitoring:

not required

Details on sampling:

Not applicable (No analytical monitoring)

Vehicle:

no

Details on test solutions:

The substance was incorporated to the diet. The diet consisted of 36% herring fish meal / 33.5% wheat / 22.5% soybean meal / 3% soybean oil / 2% vitamin mix / 1% mineral mix /2% lignosulfite (binder). In the experimental diet, 1% of soybean oil was substituted by the same amount of test substance.

The diets were pelleted (dry method) with a Templewood press in two pellet sizes: 2.5 mm (for trout 13-80 g weight) and 5 mm for the bigger sizes. Canthaxanthin (0.02%) was added to the 5 mm pellets.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: Rainbow trout
- Age at study initiation (mean and range, SD): 8 months
- Weight at study initiation (mean and range, SD): 13 g


FEEDING DURING TEST
- Food type: artificial; prepared at the laboratory
- Amount: satiation feeding
- Frequency: 4 times a day except the day before weighing

Test type:

other: Trophic exposure; flow-through tanks

Water media type:

freshwater

Limit test:

no

Total exposure duration:

31 wk

Post exposure observation period:

At the end of the exposure period, the remaining fish were divided into two groups: one group was fed at satiation 4 times a day on control diet, while the second group was maintained on total fast. Weight variations were followed for 8 weeks.

Hardness:

No data

Test temperature:

17 +/- 1 °C

pH:

no data

Dissolved oxygen:

no data

Salinity:

Not relevant (Freshwater study)

Nominal and measured concentrations:

Nominal concentration in food: 10 g/kg

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type: open
- Material, size, headspace, fill volume: 7 m * 1.5 m * 0.4 m
- Aeration: no data
- Water flow rate: 350 L/min
- No. of organisms per vessel: 800
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: 2.5 g/L


TEST MEDIUM / WATER PARAMETERS
- Tank water: spring water


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Mortality
- Weight : Lots of 100 trout, sampled using a table of random numbers were weighed weekly for the first month, then monthly
- Canthaxanthin determination in muscle, skin and remaing carcass at the pellet size change and at the end of the exposure
- Voluntary feed intake recorded weekly

Reference substance (positive control):

no

Duration:

31 wk

Dose descriptor:

other: Effect concentration

Effect conc.:

> 10 other: g/kg diet

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

31 wk

Dose descriptor:

other: Decrease

Effect conc.:

10 other: g/kg diet

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

behaviour

Remarks:

voluntary food intake

Duration:

31 wk

Dose descriptor:

other: Decrease

Effect conc.:

10 other: g/kg diet

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: Reversible: increased growth rate during the depuration phase

Duration:

31 wk

Dose descriptor:

other: Decrease

Effect conc.:

10 other: g/kg diet

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: Canthaxanthin fixation

Duration:

31 wk

Dose descriptor:

other: Decrease

Effect conc.:

10 other: g/kg diet

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: Digestion of dry matter and lipids

Details on results:

- Fish weights, weight gains and feeding parameters: see Table 1
- Other biological observations: Canthaxanthin fixation: see Table 2; Digestion of dry matter and lipids: see Table 3
- Incidents in the course of the test which might have influenced the results: None

Depuration phase (see Table 4):
- General compensatory growth in fed test fish
- Reduced weight loss in starving test fish compared to control

Results with reference substance (positive control):

No reference substance

Reported statistics and error estimates:

Student's t-test

Table 1. Effect of 1% incorporation of n-alkanes in the diet on appetite, growth and food utilisation in rainbow trout during the accumulation period.

 

Treatment	Initial mean weight (g)	Final mean weight (g)	Duration of accumulation experiment (weeks)	Weekly mean body weight increase (g/wk)	Conversion factor (Feed/∆ W)	Feed intake (% BW/day)
Control	13.4	170	26	6.02	1.61	1.55
n-alkanes	13.3	150	31	4.41	2.06	1.63

∆ W: weight increase; BW: body weight

 

Table 2. Effect of 1% incorporation of n-alkanes in the diet on canthaxanthin concentrations in different tissues of rainbow trout.

 

Treatment	Diet (µg/g)	Skin (µg/g FBW)	Muscle (µg/g FBW)	Remaining carcass (µg/g FBW)
Control	178	1.17	11.42	0.24
n-alkanes	173	1.18	5.54	0.59

FBW: Fresh body weight

 

 

Table 3. Digestion coefficients (%) calculated for dry matter and lipids in trout given diets containing n-alkanes

 

Treatment	Dry matter	Lipids
Control	57.86 ± 0.34	90.47 ± 0.70
n-alkanes	56.04 ± 1.14*	88.26 ± 0.85*

* significantly different from control (p<0.005)

 

 

Table 4. Weight variation in rainbow trout starved or fed control diet for 8 weeks at the end of the exposure period.

 

Treatment	Fed				Starving
	Final weight (g)	% increase*	Weely weight increase* (g/wk)	Conversion factor	Final weight (g)	% decrease*	Weely weight decrease* (g/wk)
Control	236	38.8	8.3	3.07	146	14.1	3
n-alkanes	231	54.0	10.1	2.61	129	14.0	2.6

* since the end of exposure

Validity criteria fulfilled:

not applicable

Conclusions:

Very long term exposure (31 weeks) to 1% n-alkanes in diet reduces fish appetite, fish growth, lipid digestibility and canthaxanthin fixation in rainbow trout. The effects are reversible.

Executive summary:

n-alkanes were incorporated into the diet (10 g/kg food) of rainbow trout to assess the effects of long-term exposure to saturated hydrocarbons. Feed intake was recorded daily and weight gain monthly.At the end of the accumulation time (31 weeks), canthaxanthin concentration was determined in the muscle, the skin and the remaining carcass. A general depressive effect of n-alkanes was observed on both appetite and growth. The reduced growth rate could not be fully explained by the decrease in food consumption. n-alkanes reduced the lipid and dry matter digestibilities as well as canthaxanthin fixation in muscle.

During a 2 month depuration period, half the trout were fed a hydrocarbon-free diet while the other half starved. A general compensatory growth was observed in the fed fish. Correspondingly, for starving trout, the weight decrease was lower for the test group than in control.

Description of key information

There is no data available for this substance. However, data to be used as a weight of evidence is available for structural analogues. 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.

1% pristane, 1%dodecylcyclohexane or 1% n-alkanes long-term exposures in fish diet reduced fish appetite, fish growth, lipid digestibility and canthaxanthin fixation in rainbow trout. The effects were reversible. No NOELR or NOEC value has been determined for long-term toxicity to fish.

Additional information

Very long term exposure (45 weeks) to 1% pristane in diet reduces fish appetite, fish growth, lipid digestibility and canthaxanthin fixation in rainbow trout. The effects are reversible.

Very long term exposure (41 weeks) to 1% dodecylcyclohexane in diet reduces fish appetite, fish growth, lipid digestibility and canthaxanthin fixation in rainbow trout. The effects are reversible.

Very long term exposure (31 weeks) to 1% n-alkanes in diet reduces fish appetite, fish growth, lipid digestibility and canthaxanthin fixation in rainbow trout. The effects are reversible.