Amines, (2-ethylhexyl)(hydrogenated tallow alkyl)methyl

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

Study period:

May 10, 2017 to July 31, 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

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 (Freshwater Alga and Cyanobacteria, Growth Inhibition Test)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Reference substance 001

Cas Number:

1078712-76-1

Molecular formula:

C23-27H49-59N (Substance is a UVCB)

Test material form:

liquid

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Samples of the test solutions were collected at approximately 0 and 72 hours for analytical
verification of the test concentrations. At test initiation (0 hour), samples were collected for each
treatment and control group prior to distribution into test chambers. At test termination (72 hours), the
biological replicates from each respective treatment and control group were pooled and then sampled. At
each sampling interval 5.0 mL of test solution was transferred into glass scintillation vials containing
5.0 mL of 0.2% formic acid in methanol.

Test solutions

Vehicle:

no

Details on test solutions:

Individual WAF solutions were prepared by mixing a calculated amount of test substance in
freshwater AAP medium at nominal loading rates of 0.26, 0.64, 1.6, 4.0, 10, and 25 mg/L. Loading rates
were not corrected for percent active ingredient in the test substance. The negative control solution
consisted of one aspirator bottle containing 4000 mL of freshwater AAP medium without test substance
added. The negative control bottles were subjected to identical mixing procedures as the Amines,
(2-ethylhexyl)(hydrogenated tallow alkyl)methyl test solutions.
Glass aspirator bottles were filled with 4000 mL of freshwater AAP medium measured with a
2000mL glass volumetric flask. Required mass of test substance for each solution was weighed into tared
30 mL glass beakers using an analytical balance and rinsed into 4000 mL glass aspirator bottles with a
portion of the freshwater AAP medium previously removed from each bottle. The actual mass of test
substance weighed for the nominal 0.26 and 0.64 mg/L treatment groups resulted in actual concentrations
of 0.25 and 0.65 mg/L. The discrepancy was caused by the precision of the analytical balance and the
differences between the actual and nominal values were considered to be negligible (0.01 mg/L). Water
accommodated fractions were stirred with a Teflon-coated stirbar and magnetic stir plate for twenty-three
hours and were allowed to settle for one hour prior to use. While stirring, a minimal vortex depth was
maintained. Precursory work conducted indicated that lower energy mixing produced better analytical
recoveries. After settling, the test solutions were decanted from mid-depth via tubing on each aspirator
bottle. Glass wool was inserted into the tubing on each bottle to avoid transferring any undissolved test
substance or particulates into the test solutions. After mixing, all test solutions appeared clear and
colorless; however, test substance was visible on the surface of the 0.26, 0.64, 1.6, 4.0, 10, and 25 mg/L
test solutions at the end of the settling period.

Test organisms

Test organisms (species):

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

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test conditions

Test temperature:

24 +/-2 C

pH:

7.5 +/- 0.1

Nominal and measured concentrations:

Nominal WAF Loading Rate
Negative Control
0.26 mg/L
0.64 mg/L
1.6 mg/L
4.0 mg/L
10 mg/L

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

72 h

Dose descriptor:

EL50

Effect conc.:

20 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 2

Duration:

72 h

Dose descriptor:

NOELR

Effect conc.:

0.64 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 3

Duration:

72 h

Dose descriptor:

EL50

Effect conc.:

2.7 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Effect concentrations 4

Duration:

72 h

Dose descriptor:

NOELR

Effect conc.:

0.64 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Any other information on results incl. tables

Results of analyses to measure concentrations of Amines, (2-ethylhexyl)(hydrogenated tallow

alkyl)methyl in test solution samples collected during the study are presented in Table 2. Measured

concentrations of Amines, (2-ethylhexyl)(hydrogenated tallow alkyl)methyl in samples collected from the

negative control at 0 and 72 hours of exposure were <LOQ. Measured concentrations of Amines,

(2-ethylhexyl)(hydrogenated tallow alkyl)methyl in samples collected from all treatment groups at 0 and

72 hours of exposure were <LOQ.

The results of the study are based on nominal WAF loading rates. Water accommodated fractions

are used for poorly soluble materials and the high masses of test substance added are not fully dissolved

in the test medium as evidence by the particulates visible in all treatment groups at the end of the mixing

period. Nominal WAF loading rates were considered to be more applicable based on the concept of WAF

studies.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes