Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 213-254-4
CAS number: 932-64-9
Reported statistics and error estimates for Inhibition of Yield:Unadjusted Treatment GroupsEyC10 (0 to 72 hour) : 9.0 mg/LEyC20 (0 to 72 hour) : 11 mg/LEyC50 (0 to 72 hour) : 14 mg/L; 95% confidence limits 13 to 15 mg/Lwhere EyCx is the test concentration that reduced yield by x%.It was not possible to calculate 95% confidence limits for the ErC50 value as the data generated did not fit the models available for the calculation of confidence limits.
Statistical analysis of the yield data was carried out as for the pH unadjusted treatment groups. There were no statistically significant differences (P≥0.05), between the control and the 1.0, 3.2 and 10 mg/L test concentrations; however, all other test concentrations were significantly different (P<0.05) and, therefore the NOEC based on yield was 10 mg/L. Correspondingly the LOEC based on yield was 32 mg/L.
pH adjusted Treatment GroupEyC10 (0 to 72 hour) : <100 mg/LEyC20 (0 to 72 hour) : >100 mg/LEyC50 (0 to 72 hour) : >100 mg/Lwhere EyCx is the test concentration that reduced yield by x%.It was not possible to calculate an EyL10 value as 18% inhibition of yield was observed.Statistical analysis of the yield data was carried out as for the pH unadjusted treatment groups. A statistically significant difference (P<0.05) was observed between the control and 100 mg/L test concentration and therefore the NOEC based was yield was determined to be less than 100 mg/L.
Cell Densities and Percentage Inhibition of Growth from the Initial Range-finding Test
Cell Densities* (cells per mL)
Inhibition Values (%)
* Cell densities represent the mean number of cells per mL calculated from the mean of the cell counts from 3 counts for each of the replicate flasks
R = Replicate
- = Not applicable
Cell Densities and Percentage Inhibition of Growth from the Second Range-finding Test
Cell Densities and pH Values in the Definitive Test
100 pH Adjusted
* Cell densities represent the mean number of cells per mL calculated from the mean of the cell counts from
3 counts for each of the replicate flasks
Daily Specific Growth Rates for the Control Cultures in the Definitive Test
Daily Specific Growth Rate (cells/mL/hour)
Day 0 to 1
Day 1 to 2
Day 2 to 3
Inhibition of Growth Rate and Yield in the Definitive Test
Nominal Concentration (mg/L)
Growth Rate (cells/mL/hour)
0 to 72 Hour
* In accordance with the OECD test guideline only the mean value for yield for each test concentration is calculated
SD = Standard Deviation
[ ] = Increase in growth as compared to the control
The mean coefficient of variation for section by section specific growth rate for the control cultures was 6% and hence satisfied the validation criterion given in the OECD Guideline which states the mean must not exceed 35%.
The coefficient of variation for average specific growth rate for the control cultures over the test period (0 to 72 hour) was 4% and hence satisfied the validation criterion given in the OECD Guideline which states that this must not exceed 7%.
According to the Biotechnology Research Institute of NRC, 2010, the 96h
EC50 was found to be 2323.7 mg/L.
The toxicity to aquatic algae was also examined by AnalyCen Ecotox AS.
The72 hours EC50 value for the test substance NTO, Nitrotriazolone was
found to be 113 mg/L.
According to Haley Mark V.,Kuperman Roman G., Checkai Ronald T. (Aquatic
Toxicity of 3-Nitro-l,2,4-triazol-5-one ), 96h NOEC for the test
substance to Scenedesmus capricornutum is 1375 mg/L; 96h LOEC for the
test substance to Scenedesmus capricornutum is 2680 mg/L.
The calculation by EPIWIN was showing EC50 of 1329.272 mg/L after 96
The toxicity of NTO to aquatic plants was assessed (Covance, 2020)
according to OECD test guideline 201 and EC method C.3. Cultures of
Raphidocelis subcapitata (formerly known as Pseudokirchneriella
subcapitata) were exposed to NTO at nominal concentrations of 1, 3.2,
10, 32 and 100 mg/L for 72 hours; a supplementary 100 mg/L concentration
level. adjusted to approximately neutral pH prior to incubation was also
In the groups without pH adjustment the 72 -hour EC50 was 19 mg/L in
terms of growth rate and 14 mg/L in terms of yield. The NOEC was 10
mg/L in terms of both rate and yield.
In the pH-adjusted group, the EC50 in terms of growth rate and yield was
> 100 mg/L. The NOEC in terms of growth rate was 100 mg/L. A NOEC
could not be calculated in terms of yeild as a statistically significant
difference between the 100 mg/L level and the control was observed.
It was observed that the test material had caused a significant decrease
in the pH in the unadjusted groups; it is considered that this may be
representative of the situation which may arise if the substance were
released into a closed aquatic system with no significant buffering
capacity and no dilution over time. It is considered that this
situation is unlikely to be representative of actual environmental
release; actual environmental release into fresh or marine water would
typically be associated with significant dilution and / or pH buffering
from the aquatic environment. On this basis the results of the
pH-adjusted test group will be used for the purposes of hazard
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
Questo sito web si avvale di cookie affinché possiate usufruire della migliore esperienza sui nostri siti web.
Welcome to the ECHA website. This site is not fully supported in Internet Explorer 7 (and earlier versions). Please upgrade your Internet Explorer to a newer version.
Do not show this message again