6-tert-butyl-2,4-xylenol

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1994

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Results taken from the SIDS Initial Assessment Report, For SIAM 4, Tokyo, Japan, 20-22 May 1996. Report not able to be located. Considered reliable as a data source used to support the SIDs programme; results collaborate with acute results that could be located. Available at http://www.inchem.org/documents/sids/sids/1879090.pdf.

Qualifier:

according to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

Deviations:

not specified

GLP compliance:

not specified

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
Not applicable.

Analytical monitoring:

not specified

Details on sampling:

Not detailed within the assessment report.

Vehicle:

not specified

Details on test solutions:

Not detailed within the assessment report.

Test organisms (species):

Daphnia magna

Details on test organisms:

Not detailed within the assessment report.

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Post exposure observation period:

Not detailed within the assessment report.

Hardness:

Not detailed within the assessment report.

Test temperature:

Not detailed within the assessment report.

pH:

Not detailed within the assessment report.

Dissolved oxygen:

Not detailed within the assessment report.

Salinity:

Not detailed within the assessment report.

Nominal and measured concentrations:

5 nominal concentrations (0.32-3.2 mg/l)

Details on test conditions:

40 daphnids (4 replicates; 10 organisms per replicate) were exposed to each of 5 nominal concentrations (0.32-3.2 mg/l)
Stock solution was prepared with DMSO:HCO-40 =9:1 (32-320 mg/l). Controls with and without this vehicle were taken for test.

Reference substance (positive control):

no

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

2.5 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

immobilisation

Remarks on result:

other: 95% confidence limits: 2.3-2.7 mg/l

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

0.6 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Remarks on result:

other: 95% confidence limits:0.59-0.60 mg/l

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

0.32 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Remarks on result:

other: (p < 0.05)

Duration:

21 d

Dose descriptor:

LOEC

Effect conc.:

0.56 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Remarks on result:

other: (p < 0.05)

Details on results:

Immobility:
EC50 (48 h) = 3.5 mg/l (95% confidence limits: 3.2-4.4 mg/l)
EC50 (21 d) = 2.5 mg/l (95% confidence limits: 2.3-2.7 mg/l)

Reproduction:
EC50 (21d)=0.60 mg/l (95% confidence limits:0.59-0.60 mg/l)
NOEC = 0.32 mg/l (p < 0.05)
LOEC = 0.56 mg/l (p < 0.05)

Results with reference substance (positive control):

Not applicable.

Reported statistics and error estimates:

As above

The SIDS Initial Assessment Report, For SIAM 4, Tokyo, Japan, 20-22 May 1996 is available at http://www.inchem.org/documents/sids/sids/1879090.pdf.

Validity criteria fulfilled:

yes

Conclusions:

As the lowest chronic toxicity result, the 21 d-NOEC (reproduction) of Daphnia magna (0.32 mg/l) was adopted. On the basis of the results noted in the study, classification under the Dangerous Substance Directive (67/548/EEC) and the CLP Regulation (EC No 1272/2008 stands as per the acute studies as follows:
N; R51/53 Dangerous for the environment; Toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment.
Chronic aquatic toxicity, Category 2; H411: Toxic to aquatic life with long lasting effects.

Executive summary:

As the lowest chronic toxicity result, the 21 d-NOEC (reproduction) of Daphnia magna (0.32 mg/l) was adopted. On the basis of the results noted in the study, classification under the Dangerous Substance Directive (67/548/EEC) and the CLP Regulation (EC No 1272/2008 stands as per the acute studies as follows:

N; R51/53 Dangerous for the environment; Toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment.

Chronic aquatic toxicity, Category 2; H411: Toxic to aquatic life with long lasting effects.

Description of key information

Chronic toxicity to daphnia is discussed.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

NOEC

Effect concentration:

0.32 mg/L

Additional information

The results for this study are taken from the SIDS Initial Assessment Report, For SIAM 4, Tokyo, Japan, 20-22 May 1996, as the full report was not able to be located. The results are considered reliable as a data source used to support the SIDs programme; results collaborate with acute results that could be located. The full report is available at

 

http://www.inchem.org/documents/sids/sids/1879090.pdf.

 

As the lowest chronic toxicity result, the 21 d-NOEC (reproduction) of Daphnia magna (0.32 mg/l) was adopted.

 

On the basis of the results noted in the study, classification under the CLP Regulation (EC No 1272/2008 stands as per the acute studies as follows:

 

Chronic aquatic toxicity, Category 2; H411: Toxic to aquatic life with long lasting effects.