Hexamethylene diisocyanate, oligomers, reaction products with 4-Hydroxybutyl acrylate

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study without restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

1

Reference substance name:

4-{[(6-{2,4,6-trioxo-3,5-bis[6-({[4-(prop-2-enoyloxy)butoxy]carbonyl}amino)hexyl]-1,3,5-triazinan-1-yl}hexyl)carbamoyl]oxy}butyl prop-2-enoate

EC Number:

929-915-1

IUPAC Name:

4-{[(6-{2,4,6-trioxo-3,5-bis[6-({[4-(prop-2-enoyloxy)butoxy]carbonyl}amino)hexyl]-1,3,5-triazinan-1-yl}hexyl)carbamoyl]oxy}butyl prop-2-enoate

Sampling and analysis

Analytical monitoring:

yes

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
The definitive test was performed using the following test item concentrations: filtrates of a loading of:
1000, 333, 111, 37, 12.3, 4.12 mg/L plus the control.
Appropriate amounts of the test item were weighed separately in glass flasks partially filled with the
AAP medium and filled up with appropriate volume of the AAP medium (Table 4) [SOP/W/7].
The mixtures were visually heterogeneous. Therefore, the mixtures and the control (the AAP medium,
1200 mL) were mechanically shaken for 48 h (30ºC, darkness, 90 revolutions per minute). After
48 hours of mechanical shaking, the mixtures (heterogeneous) and the control were stored at room
temperature for a settling phase (no shaking). After 24 hours of settling phase, the mixtures were
visually heterogeneous. Therefore, the mixtures and the control were filtered through a conditioned
nitrocellulose membrane filter (0.22 Vm, Millipore), [SOP/W/37]. This is a WAF-approach followed by
filtering which results in a water soluble fraction [9]. Filtration was chosen as the separation method
since centrifugation is not possible with the large volumes of test solution. Each filtrate was visually
homogeneous and transparent.
At exposure initiation, four samples (without algae) of the filtrate of a loading of 1000 mg/L and the
control were collected [SOP/W/83]. One of them was transferred for chemical analyses at exposure
initiation, whereas the other was stored under test conditions and transferred for chemical analyses
daily. Moreover, at exposure initiation, two samples (without algae) of the filtrates of a loading of 333,
111, 37, 12.3 and 4.12 mg/L were collected [SOP/W/83]. One of them was transferred for chemical
analyses at exposure initiation, whereas the other was stored under test conditions and transferred for
chemical analyses after 72 h of exposure.

Test organisms

Test organisms (species):

Raphidocelis subcapitata (previous names: Pseudokirchneriella subcapitata, Selenastrum capricornutum)

Details on test organisms:

TEST ORGANISM
- Common name: green algae
- Strain: SAG 61.81
- Source (laboratory, culture collection): Algae Collection University of Göttingen, Germany, cultivated at the performing institute.
- Method of cultivation: Algae were transferred from agar bevels to the fresh medium (for Pseudokirchneriella subcapitata AAP medium is recommended, Appendix 2) in 250 mL Erlenmeyer flask and incubated in 21 – 24 C in constant illumination (pre-culture) [1], [SOP/W/65]. The algae culture was renewed (inoculated to a new medium) twice a week in sterile conditions [SOP/W/56, SOP/W/70].
A pre-culture with cell density of 1 x 104 per mL was renewed three days before the definitive test. The pre-culture was used for inoculation of the test concentrations and the control.

ACCLIMATION
- Culturing media and conditions (same as test or not): yes
- Any deformed or abnormal cells observed: no

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

72 h

Test conditions

Details on test conditions:

TEST SYSTEM
- Test vessel: glass Erlenmeyer flasks 250 mL
- Type (delete if not applicable): closed with air permeable stoppers
- Material, size, headspace, fill volume: 100 mL
- Aeration: none
- Initial cells density: 10E+04 cells/mL
- Control end cells density:
- No. of vessels per concentration (replicates): 5
- No. of vessels per control (replicates): 2

GROWTH MEDIUM
- Standard medium used: yes

OTHER TEST CONDITIONS
- Adjustment of pH:
- Photoperiod: 16:8 light:dark
- Light intensity and quality:

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: spectrophotometric measurement

TEST CONCENTRATIONS
- Range finding study: yes

Reference substance (positive control):

yes

Remarks:

3,5-dichlorophenol

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

72 h

Dose descriptor:

EL50

Effect conc.:

698 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95% confidence interval: 672 – 723

Effect concentrations 2

Duration:

72 h

Dose descriptor:

EL10

Effect conc.:

369 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95% confidence interval: 340 – 396

Applicant's summary and conclusion

Validity criteria fulfilled:

yes