Xylene

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1988

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Non- GLP, guideline study, published in peer reviewed literature, acceptable with restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

yes

Remarks:

Modified as adequate for testing volatile compounds.

Principles of method if other than guideline:

Test solution was renewed after 48 hours to maintain test concentration.

GLP compliance:

not specified

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material:
Not applicable

Analytical monitoring:

yes

Details on sampling:

The concentration of the toxicant was determined at the beginning and end of the exposure and after 48 hours.

Vehicle:

no

Details on test solutions:

Diluted solutions of aromatics were prepared from saturated aqueous solutions.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

Poecilia reticulata also tested.

Test type:

other: Closed, static with renewal

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

None

Hardness:

Data not reported

Test temperature:

12°C ± 1 for Oncorhynchus mykiss and 21°C ± 1 for Poecilia reticulata

pH:

Data not reported

Dissolved oxygen:

>80% saturation

Salinity:

Not applicable

Conductivity:

N/A

Nominal and measured concentrations:

Nominal and measured concentrations not stated. Authors state that mean measured concentrations fluctuated within 10%.

Details on test conditions:

The tests were carried out in closed bottles (11 L) containing 10 animals in 10 L of test solution. At 48 hours from the beginning of the test, the solution was renewed to ensure that oxygen concentration did not fall below 80% saturation. The lethal effect was observed at 3, 6, 24, 48, 72 and 96 hours from the beginning of the experiment.

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

4.2 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Oncorhynchus mykiss

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

9.6 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Poecilia reticulata

Details on results:

Effect concentrations reported as mean measured concentrations.

Results with reference substance (positive control):

Not applicable

Reported statistics and error estimates:

Data not reported

Sublethal observations / clinical signs:

N/A

Validity criteria fulfilled:

not specified

Remarks:

insufficient data to confirm validity

Conclusions:

The reported 96 hour LC50 for Oncorhynchus mykiss is 4.2 mg/L, and for Poecilia reticulata 9.6 mg/L.

Executive summary:

The reported 96 hour LC50 for Oncorhynchus mykiss is 4.2 mg/L. This study been conducted according to OECD standard guidelines, analytical monitoring was performed and appropriate modifications for volatile compounds were made. Raw data were not included and therefore the validity of the test can not be confirmed.

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1988

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Non-GLP, guideline study, published in peer reviewed literature, acceptable with restrictions.

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

yes

Remarks:

Modified as adequate for testing volatile compounds.

Principles of method if other than guideline:

Test solution was renewed after 48 hours to maintain test concentration

GLP compliance:

not specified

Specific details on test material used for the study:

NA

Analytical monitoring:

yes

Details on sampling:

The concentration of the toxicant was determined at the beginning and end of the exposure and after 48 hours.

Vehicle:

no

Details on test solutions:

Diluted solutions of aromatics were prepared from saturated aqueous solutions.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

Poecilia reticulata (guppy) was also tested.

Test type:

other: Closed, static with renewal

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

None

Hardness:

Data not reported

Test temperature:

12°C ± 1°C for Salmo and 21°C ± 1°C for Poecilia

pH:

Data not reported

Dissolved oxygen:

>80% saturation

Salinity:

Not applicable

Conductivity:

N/A

Nominal and measured concentrations:

Nominal and measured concentrations not stated. Authors state that mean measured concentrations fluctuated within 10%.

Details on test conditions:

The tests were carried out in closed bottles (11 litres) containing 10 animals in 10 liters of test solution. At 48 hours from the beginning of the test, the solution was renewed to ensure that oxygen concentration did not fall below 80% saturation. The lethal effect was observed at 3, 6, 24, 48, 72 and 96 hours from the beginning of the experiment.

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

8.4 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

Effect concentrations reported as mean measured concentrations. 96 hour LC50 for Poecilia reticulata 12.9mg/L.

Results with reference substance (positive control):

Not applicable

Reported statistics and error estimates:

Data not reported

Sublethal observations / clinical signs:

N/A

Validity criteria fulfilled:

not specified

Remarks:

insufficient data to confirm validity

Conclusions:

The reported 96 hour LC50 for Salmo gairdneri is 8.4 mg/L.

Executive summary:

This has been chosen as the key study on the basis that it has been conducted according to OECD standard guidelines, analytical monitoring was performed and appropriate modifications for volatile compounds were made. Raw data was not included and therefore the validity of the test can not be confirmed.

Reference 3

Endpoint:

short-term toxicity to fish

Type of information:

(Q)SAR

Adequacy of study:

key study

Study period:

2015

Reliability:

2 (reliable with restrictions)

Justification for type of information:

The Target Lipid Model (TLM) is a framework that relates toxicity to the physicochemical properties of a nonpolar organic constituent. It is a well documented and peer reviewed model that is widely used across the petrochemicals industry. This substance fits within the criteria of the model and there are no reservations about the validity of the model runs. It is expected that this data is reliable with restrictions.

Qualifier:

no guideline required

Principles of method if other than guideline:

The endpoint calculated is the LL50, EL50, and NOELR -
The narcosis TLM was developed to predict the toxicity of chemicals to aquatic organisms that act via narcosis. It is based on the hypothesis that target lipid is the site of toxic action within the organism, that octanol is the appropriate surrogate, and that target lipid has the same physical–chemical properties in all organisms.
The approach describes:
• The theory and how to predict the acute toxicity to these organisms;
• Development of an Acute to Chronic ratio [ACR] for only hydrocarbons and for 29 data points.

The logkow used for calculation:
m- xylene= 3.20

Specific details on test material used for the study:

N/A

Details on sampling:

N/A

Details on test solutions:

N/A

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

N/A

Post exposure observation period:

N/A

Hardness:

N/A

Test temperature:

N/A

pH:

N/A

Dissolved oxygen:

N/A

Salinity:

N/A

Conductivity:

N/A

Nominal and measured concentrations:

N/A

Details on test conditions:

N/A

Key result

Duration:

72 h

Dose descriptor:

LL50

Effect conc.:

4.667 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Result from QSAR

Details on results:

N/A

Results with reference substance (positive control):

N/A

Reported statistics and error estimates:

N/A

Sublethal observations / clinical signs:

N/A

Conclusions:

The estimated LL50 for Oncorhynchus mykiss exposed to this substance is 4.667 mg/L. The target substance is a hydrocarbon acting via baseline toxicity, and falls within the parametric, structural and mechanistic domain of the model.

Executive summary:

The short-term aquatic toxicity to this substance was estimated using the TLM based on methodologies described by McGrath et al. (2015, 2004). The estimated LL50 for Oncorhynchus mykiss exposed to this substance is 4.667 mg/L.

Reference 4

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1988

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Non-GLP, guideline study, published in peer reviewed literature, acceptable with restrictions.

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

yes

Remarks:

Test solution was renewed after 48 hours to maintain test concentration

Principles of method if other than guideline:

Modified as adequate for testing volatile compounds.

GLP compliance:

not specified

Specific details on test material used for the study:

NA

Analytical monitoring:

yes

Details on sampling:

The concentration of the toxicant was determined at the beginning and end of the exposure and after 48 hours.

Vehicle:

no

Details on test solutions:

Data not reported

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

Tests were also performed on Poecilia reticulata.

Test type:

other: closed, static with renewal

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

None

Hardness:

Data not reported

Test temperature:

12°C ± 1°C for Salmo and 21°C ± 1°C for Poecilia

pH:

Data not reported

Dissolved oxygen:

>80% saturation

Salinity:

Not applicable

Conductivity:

N/A

Nominal and measured concentrations:

Nominal and measured concentrations not stated. Authors state that mean measured concentrations fluctuated within 10%.

Details on test conditions:

The tests were carried out in closed bottles (11 litres) containing 10 animals in 10 liters of test solution. At 48 hr from the beginning of the test, the solution was renewed to ensure that oxygen concentration did not fall below 80% saturation. The lethal effect was observed at 3, 6, 24, 48, 72 and 96 hours from the beginning of the experiment.

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

7.6 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: results refer to mean measured concentrations, whose fluctuations were within 10%.

Details on results:

96 hour LC50 for Poecilia reticulata was 12.0mg/L.

Results with reference substance (positive control):

Not applicable

Reported statistics and error estimates:

Data not reported

Sublethal observations / clinical signs:

N/A

Validity criteria fulfilled:

not specified

Remarks:

insufficient data reported to confirm validity

Conclusions:

The reported 96 hour LC50 for Salmo gairdneri was 7.6 mg/L.

Executive summary:

This has been chosen as the key study on the basis that it has been conducted according to OECD standard guidelines, analytical monitoring was performed and appropriate modifications for volatile compounds were made. Raw data was not included and therefore the validity of the test can not be confirmed.

Reference 5

Endpoint:

short-term toxicity to fish

Type of information:

(Q)SAR

Adequacy of study:

key study

Study period:

2015

Reliability:

2 (reliable with restrictions)

Justification for type of information:

The Target Lipid Model (TLM) is a framework that relates toxicity to the physicochemical properties of a nonpolar organic constituent. It is a well documented and peer reviewed model that is widely used across the petrochemicals industry. This substance fits within the criteria of the model and there are no reservations about the validity of the model runs. It is expected that this data is reliable with restrictions.

Qualifier:

no guideline required

Principles of method if other than guideline:

The endpoint calculated is the LL50, EL50, and NOELR -
The narcosis TLM was developed to predict the toxicity of chemicals to aquatic organisms that act via narcosis. It is based on the hypothesis that target lipid is the site of toxic action within the organism, that octanol is the appropriate surrogate, and that target lipid has the same physical–chemical properties in all organisms.
The approach describes:
• The theory and how to predict the acute toxicity to these organisms;
• Development of an Acute to Chronic ratio [ACR] for only hydrocarbons and for 29 data points.

The logkow used for calculation:
o-xylene= 3.12

Specific details on test material used for the study:

N/A

Details on sampling:

N/A

Details on test solutions:

N/A

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

N/A

Post exposure observation period:

N/A

Hardness:

N/A

Test temperature:

N/A

pH:

N/A

Dissolved oxygen:

N/A

Salinity:

N/A

Conductivity:

N/A

Nominal and measured concentrations:

N/A

Details on test conditions:

N/A

Key result

Duration:

72 h

Dose descriptor:

LL50

Effect conc.:

5.549 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Result from QSAR

Details on results:

N/A

Results with reference substance (positive control):

N/A

Reported statistics and error estimates:

N/A

Sublethal observations / clinical signs:

N/A

Conclusions:

The estimated LL50 for Oncorhynchus mykiss exposed to this substance is 5.549 mg/L.The target substance is a hydrocarbon acting via baseline toxicity, and falls within the parametric, structural and mechanistic domain of the model.

Executive summary:

The short-term aquatic toxicity to this substance was estimated using the Target Lipid Model based on methodologies described by McGrath et al. (2004, 2015). The estimated LL50 for Oncorhynchus mykiss exposed to this substance is 5.549 mg/L.

Reference 6

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1988

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Non-GLP, guideline study, published in peer reviewed literature, acceptable with restrictions.

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

yes

Remarks:

Test solution was renewed after 48 hours to maintain test concentration. Modified as adequate for testing volatile compounds.

GLP compliance:

not specified

Specific details on test material used for the study:

NA

Analytical monitoring:

yes

Details on sampling:

The concentration of the toxicant was determined at the beginning and end of the exposure and after 48 hours.

Vehicle:

no

Details on test solutions:

Diluted solutions of aromatics were prepared from saturated aqueous solutions.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

Poecilia reticulata also tested.

Test type:

other: Closed static with renewal

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

None

Hardness:

Data not reported

Test temperature:

12°C ± 1°C for Salmo and 21°C ± 1°C for Poecilia

pH:

Data not reported

Dissolved oxygen:

>80% saturation

Salinity:

Not applicable

Conductivity:

N/A

Nominal and measured concentrations:

Nominal and measured concentrations not stated. Authors state that mean measured concentrations fluctuated within 10%.

Details on test conditions:

The tests were carried out in closed bottles (11 litres) containing 10 animals in 10 liters of test solution. At 48 hr from the beginning of the test, the solution was renewed to ensure that oxygen concentration did not fall below 80% saturation. The lethal effect was observed at 3, 6, 24, 48, 72 and 96 hours from the beginning of the experiment.

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

2.6 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

Effect concentrations reported as mean measured concentrations. Poecilia 96 hour LC50 8.8 mg/L.

Results with reference substance (positive control):

Not applicable

Reported statistics and error estimates:

Data not reported

Sublethal observations / clinical signs:

N/A

Validity criteria fulfilled:

not specified

Remarks:

insufficient data to confirm validity

Conclusions:

The reported 96 hour LC50 for Salmo gairdneri was 2.6 mg/L.

Executive summary:

This has been chosen as the key study on the basis that it has been conducted according to OECD standard guidelines, analytical monitoring was performed and appropriate modifications for volatile compounds were made. Raw data was not included and therefore the validity of the test can not be confirmed.

Reference 7

Endpoint:

short-term toxicity to fish

Type of information:

(Q)SAR

Adequacy of study:

key study

Study period:

2015

Reliability:

2 (reliable with restrictions)

Justification for type of information:

The Target Lipid Model (TLM) is a framework that relates toxicity to the physicochemical properties of a nonpolar organic constituent. It is a well documented and peer reviewed model that is widely used across the petrochemicals industry. This substance fits within the criteria of the model and there are no reservations about the validity of the model runs. It is expected that this data is reliable with restrictions.

Qualifier:

no guideline required

Principles of method if other than guideline:

The endpoint calculated is the LL50, EL50, and NOELR -
The narcosis TLM was developed to predict the toxicity of chemicals to aquatic organisms that act via narcosis. It is based on the hypothesis that target lipid is the site of toxic action within the organism, that octanol is the appropriate surrogate, and that target lipid has the same physical–chemical properties in all organisms.
The approach describes:
• The theory and how to predict the acute toxicity to these organisms;
• Development of an Acute to Chronic ratio [ACR] for only hydrocarbons and for 29 data points.

The logkow used for calculation:
p-xylene= 3.09

Specific details on test material used for the study:

N/A

Details on sampling:

N/A

Details on test solutions:

N/A

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

N/A

Post exposure observation period:

N/A

Hardness:

N/A

Test temperature:

N/A

pH:

N/A

Dissolved oxygen:

N/A

Salinity:

N/A

Conductivity:

N/A

Nominal and measured concentrations:

N/A

Details on test conditions:

N/A

Key result

Duration:

72 h

Dose descriptor:

LL50

Effect conc.:

5.921 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Result from QSAR

Details on results:

N/A

Results with reference substance (positive control):

N/A

Reported statistics and error estimates:

N/A

Sublethal observations / clinical signs:

N/A

Conclusions:

The estimated LL50 for Oncorhynchus mykiss exposed to this substance is 5.921 mg/L. The target substance is a hydrocarbon acting via baseline toxicity, and falls within the parametric, structural and mechanistic domain of the model.

Executive summary:

The short-term aquatic toxicity to this substance was estimated using the TLM based on methodologies described by McGrath et al. (2004, 2015). The estimated LL50 for Oncorhynchus mykiss exposed to this substance is 5.921 mg/L.

Reference 8

Endpoint:

short-term toxicity to fish

Type of information:

(Q)SAR

Adequacy of study:

key study

Study period:

2015

Reliability:

2 (reliable with restrictions)

Justification for type of information:

The Target Lipid Model (TLM) is a framework that relates toxicity to the physicochemical properties of a nonpolar organic constituent. It is a well documented and peer reviewed model that is widely used across the petrochemicals industry. This substance fits within the criteria of the model and there are no reservations about the validity of the model runs. It is expected that this data is reliable with restrictions.

Qualifier:

no guideline required

Principles of method if other than guideline:

The endpoint calculated is the LL50, EL50, and NOELR -
The narcosis TLM was developed to predict the toxicity of chemicals to aquatic organisms that act via narcosis. It is based on the hypothesis that target lipid is the site of toxic action within the organism, that octanol is the appropriate surrogate, and that target lipid has the same physical–chemical properties in all organisms.
The approach describes:
• The theory and how to predict the acute toxicity to these organisms;
• Development of an Acute to Chronic ratio [ACR] for only hydrocarbons and for 29 data points.

The logkow used for calculation:
xylene = 3.16

Specific details on test material used for the study:

N/A

Details on sampling:

N/A

Details on test solutions:

N/A

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

N/A

Post exposure observation period:

N/A

Hardness:

N/A

Test temperature:

N/A

pH:

N/A

Dissolved oxygen:

N/A

Salinity:

N/A

Conductivity:

N/A

Nominal and measured concentrations:

N/A

Details on test conditions:

N/A

Key result

Duration:

72 h

Dose descriptor:

LL50

Effect conc.:

5.089 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Result from QSAR

Details on results:

N/A

Results with reference substance (positive control):

N/A

Reported statistics and error estimates:

N/A

Sublethal observations / clinical signs:

N/A

Conclusions:

The estimated LL50 for this substance is 5.089 mg/L. The target substance is a hydrocarbon acting via baseline toxicity, and falls within the parametric, structural and mechanistic domain of the model.

Executive summary:

The short-term aquatic toxicity to this substance was estimated using the Target Lipid Model based on methodologies described by Mcgrath et al. (2004). The estimated LL50 for Oncorhynchus mykiss exposed to this substance is 5.089 mg/L.

Description of key information

The lowest 96 hour LC50 is 2.6 mg/L for p-xylene.

The estimated LL50 values from TLM QSAR were 4.667 - 5.921 mg/L.

The lowest value was used for chemical safety assessment.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

LC50

Effect concentration:

2.6 mg/L

Additional information

Data are available on the acute toxicity of each of the xylene isomers and ethylbenzene to fish. The studies by Galassi et al (1988), Springborn (1994) and DiMarzio et al (2004) follow OECD 203, whilst Holcombe et al (1987) used a flow through system to expose different species simultaneously. Galassi et al (1988), Springborn (1994) and Holcombe et al (1987) used a standard test species, whilst DiMarzio et al (2004) tested a nonstandard freshwater fish. All studies included analytical confirmation of the exposure concentrations.

The 96hr LC50 results reported from the key studies from Galassi et al (1988) for o-xylene, m-xilene p-xylene and ethylbenzene are 7.6, 8.4, 2.6 and, 9.6 mg/L respectively. The most conservative result from the individual isomers and ethylbenzene will be used in the risk assessment.

A TLM modeling framework was used to support values derived experimentally.The estimated LL50 values from TLM QSAR were 4.667 - 5.921 mg/L.