Registration Dossier

Diss Factsheets

Ecotoxicological information

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
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Guideline study conducted under GLP

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Report date:
2011

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
Deviations:
no
GLP compliance:
yes (incl. QA statement)

Test material

1
Reference substance name:
Hydrogenated rosin alcohols
Cas Number:
2156595-41-2
IUPAC Name:
Hydrogenated rosin alcohols
Test material form:
liquid: viscous
Details on test material:
Sponsor's identification: Technical Hydroabietyl Alcohol
Description: Light amber coloured extremely viscous liquid
Lot number: HR-078
Purity: 100% (UVCB)
Expiry date: 21 December 2012
Storage conditions: Room temperature in the dark

Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
Water temperature was recorded daily throughout the test. Dissolved oxygen concentrations and pH were recorded at the start and termination of the test.

Water samples were taken from the control and each loading rate WAF test group (replicates R1 - R2 pooled) at 0 and 48 hours for quantitative analysis. All samples were stored at approximately -20°C prior to analysis.

Test solutions

Vehicle:
no
Details on test solutions:
Pre-study investigational work was carried out to determine whether stirring for a prolonged period produced significantly higher levels of total organic carbon, as an indicator of soluble organic substances, in the WAF. A WAF of nominal loading rate of 100 mg/L was prepared, in duplicate, in deionised reverse osmosis water. One loading rate was stirred for a period of 23 hours and the other for a period of 95 hours. After a 1-Hour standing period the mixtures were then removed by siphon and samples taken for Total Organic Carbon analysis It was determined from this pre-study work that increasing the stirring period did not significantly increase the amount of carbon in the WAF and so preparation of the WAF was maintained at 24 hours.

Amounts of test item (100, 180, 320, 560 and 1000 mg) were each separately added to 10 litres of reconstituted water to give the 10, 18, 32, 56 and 100 mg/L loading rates respectively. Test item for the 56 and 100 mg/L loading rates was added to the water surface, however due to its highly viscous nature, test item for the 10, 18 and 32 mg/L loading rate was applied to a glass slide which was suspended in the top of the water column. After the addition of the test item, the reconstituted water was stirred by magnetic stirrer using a stirring rate such that a vortex was formed to give a dimple at the water surface. The stirring was stopped after 23 hours and the mixtures allowed to stand for 1 hour. A wide bore glass tube, covered at one end with Nescofilm was submerged into the vessel, sealed end down, to a depth of approximately 5 cm from the bottom of the vessel. A length of Tygon tubing was inserted into the glass tube and pushed through the Nescofilm seal. The aqueous phase or WAF was removed by mid-depth siphoning (the first approximate 75-100 ml discarded) to give the 10, 18, 32, 56 and 100 mg/L loading rate WAFs. Microscopic inspection of the WAFs showed no microdispersions or undissolved test item to be present.

Test organisms

Test organisms (species):
Daphnia magna
Details on test organisms:
The test was carried out using 1st instar Daphnia magna derived from in-house laboratory cultures. Adult Daphnia were maintained in glass beaks containing Elendt M7 media in a temperature controlled room at approximately 20°C. The lighting cycle was controlled to give a 16 hours light and 8 hours darkness cycle with 20 minute dawn and dusk transition periods. Each culture was fed daily with a mixture of algal suspension (Desmodesmus subspicatus) and Tetramin® flake food suspension. Culture conditions ensured that reproduction was by parthenogenesis. Gravid adults were isolated the day before initiation of the test, such that the young daphnids produced overnight were less than 24 hours old. These young were removed from the cultures and used for testing. The diet and diluent water are considered not to contain any contaminant that would affect the integrity or outcome of the study.

Study design

Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
48 h

Test conditions

Hardness:
250 mg/L as CaCO3
Test temperature:
Temperature was maintained at 21 to 22°C throughout the test. Some of the temperatures were observed to be slightly in excess of the range given in the study plan of 20 ± 1 °C. This deviation was considered not to have affected the outcome or the validity of the test as no adverse effects of exposure were observed in the control daphnids throughout the duration of the test and that the temperature range was within guideline specification.
pH:
7.6-8.0
Dissolved oxygen:
8.4-8.8 mg/L
Details on test conditions:
In the range-finding test Daphnia magna were exposed to a series of nominal loading rates of 1.0, 10 and 100 mg/L. The test item was heated to
approximately 1 00°C prior to use to reduce viscosity. In the range-finding test 10 daphnids were placed in each test and control vessel and maintained in a temperature controlled room at 21 to 22°C with a photoperiod of 16 hours light and 8 hours darkness for a period of 48 hours with 20 minute dawn and dusk transition periods.

Based on the results of the range-finding test the following loading rates were assigned to the definitive test: 10, 18, 32, 56 and 100 mg/L. In the definitive test 250 ml glass jars containing approximately 250 ml of test preparation were used. At the start of the test 10 daphnids were placed in each test and control vessel at random, in the test preparations. Duplicate test vessels were used for each test and control group. The test vessels were then covered to reduce evaporation and maintained in a temperature controlled room at 21 to 22°C with a photoperiod of 16 hours light and 8 hours darkness with 20 minute dawn and dusk transition periods. Any immobilisation or adverse reactions to exposure were recorded at 24 and 48 hours after the start of exposure.

The results from the definitive test differed from that of the range-finding test in that no significant immobilisation was observed at any of the loading rates used. In addition, the analytical results differed between the range-finding and definitive tests A further test was therefore conducted to confirm the results of the definitive test. In the confirmatory test Daphnia magna were exposed to a series of nominal loading rates of 10 and 100 mg/L. In the confirmatory test 10 daphnids were placed in each test and control vessel and maintained in a temperature controlled room at approximately 20C with a photoperiod of 16 hours light and 8 hours darkness for a period of 48 hours with 20 minute dawn and dusk transition periods. Each 250 ml test and control vessel contained 250 ml of test media and was covered to reduce evaporation. After 24 and 48 hours the number of immobilised Daphnia magna were recorded.

Results and discussion

Effect concentrationsopen allclose all
Duration:
48 h
Dose descriptor:
EL50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Duration:
48 h
Dose descriptor:
NOELR
Effect conc.:
>= 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Details on results:
lmmobilisation data

Range-finding Test
Two immobilised daphnids were observed at 1.0 mg/L loading rate WAF however this was considered to be due to natural causes rather than a toxic effect given that no immobilisation was observed in the 10 mg/L loading rate WAF. Significant immobilisation was observed at 100 mg/L loading rate WAF.

Definitive Test
There was no immobilisation in 20 daphnids exposed to 10, 18, 32 and 56 mg/L loading rate WAFs for a period of 48 hours. A single immobilised daphnid was observed at the 100 mg/L loading rate WAF however this was considered to be due to natural causes rather than a toxic effect given that only 5% immobilisation was observed.

Confirmatory Test
Due to differences in results between the range-finding study and the definitive study a confirmatory study was conducted at 10 and 100 mg/lloading rate WAFs. No immobilisation was observed at the 10 and 100 mg/L loading rate WAFs confirming the results from the definitive test.

Analytical Verification of samples

In the range-finding test chemical analysis of the 10 and 100 mg/L loading rate WAF test preparations showed measured test concentrations of 0.00792 and 0.452 mg/L respectively at 0 hours and 0.00679 and 0.111 mg/1 at 48 hours. In the definitive study analysis of the 100 mg/L loading rate WAF test preparation at 0 and 48 hours showed measured concentrations to be 0.031 and 0.017 mg/L respectively. In the confirmatory study analysis of the 100 mg/L loading rate WAF test preparation at 0 and 48 hours showed measured concentrations to be 0.0328 and 0.0203 mg/L respectively, similar to those found in the definitive test, suggesting that the immobilisation observed at 100 mg/L loading rate WAF in the range-finding test may have been due test item being siphoned off into the WAF.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Executive summary:

A study was performed to assess the acute toxicity of the test item to Daphnia magna. The method followed was designed to be compatible with the OECD Guidelines for Testing of Chemicals (April 2004) No 202, "Daphnia sp, Acute lmmobilisation Test". Following a preliminary range-finding test, twenty daphnids (2 replicates of 10 animals) were exposed to Water Accommodated Fractions (WAFs) of the test item over a range of nominal loading rates of 10, 18, 32, 56 and 100 mg/L for 48 hours at a temperature of 21 to 22°C under static test conditions. The number of immobilised Daphnia were recorded after 24 and 48 hours. The 48-Hour EL50 for the test item to Daphnia magna based on nominal loading rates was greater than 100 mg/L loading rate WAF. The No Observed Effect Loading rate was 100 mg/L loading rate WAF. Analysis of the 100 mg/L loading rate WAF test preparation at 0 and 48 hours showed measured concentrations to be 0.031 and 0.017 mg/L respectively. Given that the toxicity cannot be attributed to a single component or a mixture of components but to the test item as a whole the results were based on nominal loading rates only.