Benzene, C15-16-alkyl derivs.

Long-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

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

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable, well-documented publication which meets basic scientific principles.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1991

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: -Draft No. 5 - Committee E-35.21: proposed Standard Practice for Conducting Renewal Life cycle Toxicity Tests with Daphnids

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Benzene, C10-16-alkyl derivs.

EC Number:

272-008-4

EC Name:

Benzene, C10-16-alkyl derivs.

Cas Number:

68648-87-3

IUPAC Name:

tridecylbenzene

Constituent 2

Reference substance name:

C10-14 LAB

IUPAC Name:

C10-14 LAB

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Analysis was performed on day 0, 4, 7, 14, and 21

Test solutions

Vehicle:

yes

Details on test solutions:

Vehicle: acetone

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

Age: First-instar Daphnia
During the test, Daphnia were fed algae three times daily and trout chow once daily. Survival and reproduction were recorded and assessed three times a week.

Study design

Test type:

flow-through

Limit test:

no

Total exposure duration:

21 d

Test conditions

Hardness:

255 mg/l as CaCO3

Test temperature:

20-21 °C

pH:

8.0-8.4

Dissolved oxygen:

5.8-8.4 mg/l

Nominal and measured concentrations:

1.9, 3.8, 7.5, 15 and 30 µg/l

Details on test conditions:

The tests were conducted in a flow-through proportional diluter system, with a solvent (1 ml/l acetone). There were ten first-instar Daphnia (< 24h old) in each of the four replicate chambers for each test substance concentration, the control and the solvent control. Survival and reproduction were recorded and assessed three times a week. Growth was established only at day 21 by measuring mature daphnids. Biological parameters included adult survival, total young produced and young produced per adult and were summarized on days 0, 4, 7, 14 and 21.

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

0.007 mg/L

Effect concentrations 2

Duration:

21 d

Dose descriptor:

LOEC

Effect conc.:

0.015 mg/L

Effect concentrations 3

Duration:

21 d

Dose descriptor:

other: MATC

Effect conc.:

0.007 - 0.015 mg/L

Effect concentrations 4

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

0.012 mg/L

Details on results:

Results indicate both reproduction and growth to be affected
at the 15 and 30 µg/L treatment levels. Acute studies with
D. magna conducted by the same authors using either acetone or
DMF as a solvent resulted in acute 48-hour EC50s ranging from
9 to 80 µg/L.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The 21 day EC50 for daphnids was 0.012 mg/l test substance.

Executive summary:

In cases where no data were available on the target substance, Benzene, C15 -16 -alkyl derivs., data were read across from a structurally related material (the test substance).

This study determined the chronic toxicity of the test substance to aquatic invertebrates. Groups of 10 daphnids were exposed to concentrations of 1.9, 3.8, 7.5, 15 or 30 ug/l of test substance for 21 days. Biological parameters included adult survival, total young produced and young produced per adult and were summarized on days 0, 4, 7, 14 and 21. Reproduction and growth was reduced at concentrations between 15 -30 ug/l. The 21 -day NOEC for daphnids was 0.0075 mg/l. The 21 -day LOEC was 0.015 mg/l. The 21 -day EC50 for daphnids was 0.012 mg/l.