8,9,10-trinorborna-2,5-diene

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

February-April 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

8,9,10-trinorborna-2,5-diene

EC Number:

204-472-0

EC Name:

8,9,10-trinorborna-2,5-diene

Cas Number:

121-46-0

Molecular formula:

C7H8

IUPAC Name:

bicyclo[2.2.1]hepta-2,5-diene

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and batch number of test material: Air Liquide Electronics Materials. Batch 1590035136 / 1590035137
- Purity: 100% w/w
- Manufacturing date: August 25, 2017
- Deadline to use : August 16, 2018

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Room temperature (20±5°C)
- Stability and homogeneity of the test material and during storage: stable

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

In order to verify the initial concentrations and maintenance of the exposure concentrations of the test item during the ecotoxicological testing, chemical analysis in daphnids test solutions WAF) were performed according to the Analytical protocol FCBA Chimie No.386-e version 2: Method for the chemical analysis of BCHD from daphnids ecotoxicology solutions by HPLC/DAD (see study 17/1094F/c) for the Control (i.e. filtered daphnids test medium), and at the lowest, the highest concentrations and a concentration around the expected EC50 concentration.

Test solutions

Vehicle:

no

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

Clone number 5 from at least the third generation obtained with a non-cyclic parthenogenesis reproduction

Study design

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Test conditions

Hardness:

250 - 260 mg/L of CaCO3

Test temperature:

19.5-20.0 °C

pH:

7.7 - 8.1

Dissolved oxygen:

8.4 - 9.3 mg/L

Nominal and measured concentrations:

This study was conducted on six concentrations level: 10.0 - 14.0 - 19.6 - 27.4 - 38.4 and 54.0 mg/L.
The measured concentrations of the "BCHD" did not vary more than ± 20% of nominal or initial measured concentration during the test (variations between -9.3% and +0.6%).

Reference substance (positive control):

yes

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

30.25 mg/L

95% CI:

>= 27.92 - <= 33.15

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 2

Key result

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

15.75 mg/L

95% CI:

>= 14.47 - <= 17.14

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Results with reference substance (positive control):

The last toxic response obtained on the reference item K2Cr2O7 indicates an EC50-24h of 1.59 mg/L (1.45 — 1.74), indicating that the daphnids sensitivity is correct (within the accepted interval of 0.6—2.1 mg/L fixed by the International Standard ISO 6341 December 2012 as mentioned in the OECD 202 Guideline) and in accordance with historical data obtained by the laboratory.

Any other information on results incl. tables

Nominal test item loading rate in mg/L	Number of daphnids exposed at the start	Immobilised daphnids (%)
		at 24h	at 48h
WAF Control	20	0 (0%)	0 (0%)
WAF 10.0	20	0 (0%)	0 (0%)
WAF 14.0	20	0 (0%)	5 (25%)
WAF 19.6	20	1 (5%)	18 (90%)
WAF 27.4	20	2 (10%)	20 (100%)
WAF 38.4	20	20 (100%)	20 (100%)
WAF 54.0	20	20 (100%)	20 (100%)

 

In order to check the stability of the WAFs in the test solutions, concentration of BCHD in the control and the WAFs was checked by HPLC/DAD at start (t=0h), at t=24h (new and old solutions) and at the end of the test (t=48h).

Overview of the results is given in the table below:

Nominal test item loading rate	Renewal	Results of the determination of BCHD analysis (mg/L)
		At initial time (fresh solultions)	After 24 hours of exposure (Old solutions)	Variation (%)
WAF 10.0 mg/L	T0h to T24h	2.62	2.46	• 6.1
WAF 10.0 mg/L	T24h to T48h	6.53	5.92	- 9.3
WAF 27.4 mg/L	T0h to T24h	7.56	7.32	- 3.2
WAF 27.4 mg/L	T24h to T48h	15.9	16.0	+ 0.6
WAF 54 mg/L	T0h to T24h	22.4	22.0	- 1.8
WAF 54 mg/L	T24h to T48h	NA	NA	NA

NA: Not Applicable (no rewal for the highest concentration at T24h because all the daphnids were dead)

According to the results of the BCHD analysis and since the study was carried out using WAFs, the results were based on the nominal test item loading rates.

 

 

Validity criteria conformity:

	Values for OECD 202	Validity criteria for the test
Immobilised daphnids in control	< 10%	Ok (0%)
Dissolved Oxygen concentration	3 mg/L	Ok (8.4 mg/L)

All the validity criteria were successful.

 

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

All the validity criteria were successful.
The results obtained for the test item "BCHD" on the toxicological endpoint "immobilisation" give an EL50-24h = 30.25 mg/L [27.92-33.15] and an EL50-48h = 15.75 mg/L [14.47 - 17.14] based on nominal test item loading rate.

Executive summary:

The aim of this study was to determine the acute toxicity of the test item "BCHD" on the daphnids Daphnia magna, according to the OECD guideline 202. The daphnids were exposed to Water Accommodated Fractions (WAFs) of the test item, following the 'Guidance document on aquatic toxicity testing of difficult substances and mixtures" (OECD No. 23).

Following the results of a preliminary study, a final test at six nominal loading rate was performed, in order to evaluate the loading rate which immobilise X% of the daphnids exposed to the test item after 24 and 48 hours, reported as ELx-24h and ELx-48h, relative to tested concentrations.

The immobility of the daphnids was determined in a closed semi-static 48-hours test by visual observation after 24 and 48 hours.

In order to check the stability of the WAFs in the test solutions, concentration of BCHD in the control and the WAFs was checked by HPLC/DAD at start (t=0h), at t=24h (new and old solutions) and at the end of the test (t=48h).

According to the results of the BCHD analysis and since the study was carried out using WAFs, the results were based on the nominal test item loading rates.

Validity criteria conformity: All the validity criteria were successful.

The obtained for the test item "BCHD" on the toxicological endpoint "immobilisation" give an EL50-24h = 30.25 mg/L [27.92 - 33.15] and an EL50-48h = 15.75 mg/L [14.47 - 17.14] based on nominal test item loading rate.

These values are based on nominal test item "BCHD" loading rate.