2,4,7,9-tetramethyldec-5-yne-4,7-diol

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2000

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: according to EC Directive 92/69/EEC and Regulation EC/440/2008 guideline methods under GLP conditions

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

GLP compliance:

yes

Specific details on test material used for the study:

Batch No 11029
Purity 98,3%
white solified mass

Analytical monitoring:

yes

Details on sampling:

Analytical measurements in the pre-test showed that the test substance is stable during the 96 hours exposure period. Test was performed as a static test, samples were taken at the beginning and the end of the exposure period. 10 ml were taken from the centre of the test vessel

Details on test solutions:

Test substance, a solidified mass, was heted for 1 hour at 90°C until it became a clear yellow viscious liquid. The test substance was completely soluble in the test medium at 100 mg/L. Magnetic stirring was applied to dissolve the test substance in the test medium. All other concentrations were prepared by dilution. Final test solutions were clear and colourless.

Test organisms (species):

Cyprinus carpio

Details on test organisms:

Source of fish: Zodiac, proefacc, "De Haar Vissen", L.U., Wageningen, the Netherlands
Mean length Range-finding test: 3.02 +/- 0.23 cm, Final test: 2.7 +/-0.24 cm
Mean weight Range-finding test: 1.12 +/- 0.30 g, Final test: 0.48 +/- 0.1 8 g
Characteristics: F1 from a single parent-pair bred in UV-treated water.
Reason for selection: This system has been selected as an internationally
accepted species.
Total fish used: 54
QuarantineIAcclimation At least 12 days after delivery
In the batch of fish used for the test, mortality during the seven days prior to the start of the test was less than 5%.

Test type:

static

Water media type:

freshwater

Total exposure duration:

96 h

Hardness:

250 mg CaCO3/l

Test temperature:

The test temperature ranged from 20.2 to 20.8 degrees C. 

pH:

The pH ranged from 8.1 to 7.5 

Dissolved oxygen:

dissolved oxygen ranged from 5.9 to 9.2 mg/l

Nominal and measured concentrations:

nominal concentrations final test: 10, 18, 32, 56 and 100 mg/L
measured concentration final test 0 hours (concentrations of 10, 32 and 100 mg/L were measured): 9.51, 28.3 and 88.6 mg/L
measured concentration final test 96 hours (concentrations of 10 and 32 mg/L were measured): 8.48 and 27.3 mg/L

Details on test conditions:

Test type Static
Test vessels 6 litres, all-glass.
Test medium: ISO-medium, aerated until the dissolved oxygen
concentration had reached saturation and the pH had stabilised. After aeration the hardness was 250 mg CaC03 per litre and the pH was 8.0.
Number of fish: 7 fish per concentration and control
Loading: 0.67 g fishflitre, i.e. 7 fish per 5 litres of test medium.
Illumination: 16 hours photoperiod daily
Aeration: Aeration was introduced after 24 hours of exposure
Feeding: No feeding from 48 hours prior to the test and during the total test period.
Introduction of fish: Directly after preparation of the test media

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

10 mg/L

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

32 mg/L

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

42 mg/L

Duration:

96 h

Dose descriptor:

LC100

Effect conc.:

56 mg/L

Results with reference substance (positive control):

96 hours LC50 with pentachlorophenol was 0.09 mg/L

Reported statistics and error estimates:

The LC50 could not be determined using the maximum likelihood estimation method with the
probits of the percentages of dead fish as function of the logarithms of the corresponding
concentrations (Finney, D.J., 1971 : Probit analysis, Cambridge University Press, Cambridge,
U.K., 3rd edition). This was because there was no concentration between the highest
concentration (A) at which 0% mortality and the lowest concentration (B) at which 100%
mortality occurred. Instead, the LC50 was calculated as (AB)" , with A and B being limits of the
95% confidence interval

Sublethal observations / clinical signs:

The 24h- and 96h-LC50 for carp exposed to 2,4,7,9-Tetramethyl-5-Decyne-4,7-Diol was 42 mg/l with 0
percent mortality at 32 mg/l (LC0) and 100 percent mortality at 56 mg/l (LC100). Concentrations down to 18 mg/l induced effects on swimming behavior and pigmentation, while no sub-lethal effects occurred at 10 mg/l.

Validity criteria fulfilled:

yes

Conclusions:

The 96h-LC50 for carp exposed to 2,4,7,9-TETRAMETHYL-5-DECYNE-4,7-DIOL was already
reached after 24 hours of exposure and was 42 mg/l with 0% mortality at 32 mg/l (LC0) and
100% mortality at 56 mg/l (LC100). Concentrations down to 18 mg/l induced effects on swimming
behaviour and pigmentation, while no sub-lethal effects occurred at 10 mg/l.

Executive summary:

First a range-finding test was conducted with exposure of
fish to 0.1, 1.0, 10 and 100 mg/l. All fish died at 100 mg/l
within 2.5 hours after the start of the test, while no fish
died at 10 mg/l. Analysis of samples taken at 10 mg/l showed
that this concentration was stable during the 96-hour test
period. 

After the range-finding test, a final test was performed
with carp exposed to concentrations of 0, 10, 18, 32, 56 and
100 mg/l in a static system. Seven carp were exposed per
concentration and a control. The loading was 0.67 g
fish/liter.  At the start of test, the water hardness was
250 mg CaCO3 per liter, the dissolved oxygen concentration
was saturated, and the water pH was 8.0.  The dissolved
oxygen, water pH, and temperature were measured daily. 
Samples for analytical confirmation of actual exposure
concentrations were taken at the start and the end of the
test. 

Analysis of the samples taken during the final test showed
that the measured concentrations in the samples taken at the
start of the test were 9.5 mg/l (95 percent), 28.3 mg/l (89
percent) and 88.6 mg/l (89 percent) at the nominal
concentrations of 10, 32 and 100 mg/l, respectively. The
measured concentrations at 32 and 100 mg/l could be related
to lower recoveries found at 180 mg/l in a recovery control
experiment (87-90 percent). Hence, the actual concentrations
in these samples were considered to be in agreement with
nominal.  At the end of the test period measured
concentrations had not decreased by more than 20 percent of
the initial concentrations. As a result, toxicity parameters
were based on nominal concentrations.

Description of key information

The 96h-LC50 for carp exposed to 2,4,7,9-TETRAMETHYL-5-DECYNE-4,7-DIOL was already
reached after 24 hours of exposure and was 42 mg/l with 0% mortality at 32 mg/l (LC0) and
100% mortality at 56 mg/l (LC100). Concentrations down to 18 mg/l induced effects on swimming
behaviour and pigmentation, while no sub-lethal effects occurred at 10 mg/l

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

LC50

Effect concentration:

42 mg/L