Registration Dossier
Registration Dossier
Data platform availability banner - registered substances factsheets
Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.
The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.
Diss Factsheets
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: 276-380-9 | CAS number: 72140-65-9
- Life Cycle description
- Uses advised against
- Endpoint summary
- Appearance / physical state / colour
- Melting point / freezing point
- Boiling point
- Density
- Particle size distribution (Granulometry)
- Vapour pressure
- Partition coefficient
- Water solubility
- Solubility in organic solvents / fat solubility
- Surface tension
- Flash point
- Auto flammability
- Flammability
- Explosiveness
- Oxidising properties
- Oxidation reduction potential
- Stability in organic solvents and identity of relevant degradation products
- Storage stability and reactivity towards container material
- Stability: thermal, sunlight, metals
- pH
- Dissociation constant
- Viscosity
- Additional physico-chemical information
- Additional physico-chemical properties of nanomaterials
- Nanomaterial agglomeration / aggregation
- Nanomaterial crystalline phase
- Nanomaterial crystallite and grain size
- Nanomaterial aspect ratio / shape
- Nanomaterial specific surface area
- Nanomaterial Zeta potential
- Nanomaterial surface chemistry
- Nanomaterial dustiness
- Nanomaterial porosity
- Nanomaterial pour density
- Nanomaterial photocatalytic activity
- Nanomaterial radical formation potential
- Nanomaterial catalytic activity
- Endpoint summary
- Stability
- Biodegradation
- Bioaccumulation
- Transport and distribution
- Environmental data
- Additional information on environmental fate and behaviour
- Ecotoxicological Summary
- Aquatic toxicity
- Endpoint summary
- Short-term toxicity to fish
- Long-term toxicity to fish
- Short-term toxicity to aquatic invertebrates
- Long-term toxicity to aquatic invertebrates
- Toxicity to aquatic algae and cyanobacteria
- Toxicity to aquatic plants other than algae
- Toxicity to microorganisms
- Endocrine disrupter testing in aquatic vertebrates – in vivo
- Toxicity to other aquatic organisms
- Sediment toxicity
- Terrestrial toxicity
- Biological effects monitoring
- Biotransformation and kinetics
- Additional ecotoxological information
- Toxicological Summary
- Toxicokinetics, metabolism and distribution
- Acute Toxicity
- Irritation / corrosion
- Sensitisation
- Repeated dose toxicity
- Genetic toxicity
- Carcinogenicity
- Toxicity to reproduction
- Specific investigations
- Exposure related observations in humans
- Toxic effects on livestock and pets
- Additional toxicological data
![](https://poisoncentres.echa.europa.eu/o/diss-blank-theme/images/factsheets/A-REACH/factsheet/print_ecotoxicological-information.png)
Toxicity to microorganisms
Administrative data
Link to relevant study record(s)
- Endpoint:
- activated sludge respiration inhibition testing
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- 25 May - 01 Jul 2016
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- guideline study
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test (Carbon and Ammonium Oxidation))
- Deviations:
- no
- Qualifier:
- according to guideline
- Guideline:
- EU Method C.11 (Biodegradation: Activated Sludge Respiration Inhibition Test)
- Deviations:
- no
- GLP compliance:
- yes
- Specific details on test material used for the study:
- SOURCE OF TEST MATERIAL
- Appearance: white, waxy solid
- Source and lot/batch No.of test material: 605803
- Expiration date of the lot/batch: 31 Dec 2016
- Purity: 98.4%
- Purity test date: 25 Nov 2015
STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: At room temperature
- Stability under test conditions: Substance is hydrolytically active - Analytical monitoring:
- no
- Vehicle:
- no
- Details on test solutions:
- Because the test substance is not stable in aqueous solution, the substance was melted and applied to watch glasses. After cooling and weighing, the watch glasses were added directly to test vessels containing 200 mL tap water purified by reverse osmosis.
- Test organisms (species):
- activated sludge of a predominantly domestic sewage
- Details on inoculum:
- - Name and location of sewage treatment plant where inoculum was collected: Municipal sewage treatment plant: 'Waterschap Aa en Maas', 's- Hertogenbosch, The Netherlands, receiving predominantly domestic sewage.
- Preparation of inoculum for exposure: The sludge was coarsely sieved (1 mm) and allowed to settle. The supernatant was removed and ISO-medium was added. A small amount of the sludge was weighed and dried overnight at ca. 105°C to determine the amount of suspended solids (3.0 g/L of sludge, as used for the test). The pH was 7.9 on the day of testing. The batch of sludge was used one day after collection; therefore 50 mL of synthetic medium was added per litre of activated sludge at the end of the collection day. The sludge was kept aerated at test temperature until use. - Test type:
- static
- Water media type:
- freshwater
- Limit test:
- no
- Total exposure duration:
- 3 h
- Hardness:
- Not reported
- Test temperature:
- 18 - 21 °C
- pH:
- Start, 7.7 - 7.8 before addition of sludge
7.4 - 8.4 after 3-hr exposure period - Nominal and measured concentrations:
- Nominal concentrations only: 10 mg/L, 32 mg/L, 100 mg/L, 320 mg/L, and 1000 mg/L during exposure period.
- Details on test conditions:
- TEST SYSTEM
- Test vessel: All glass bottles/vessels.
- Type (delete if not applicable): Open during exposure. Respiration measured in closed cell with multiple oxygen probes connected to a BlueBox (GO-Systemelektronik GmbH, Germany) multichannel measuring and controlling system.
- Material, size, headspace, fill volume: 200 mL purified water plus test substance, 16 mL synthetic sewage, and 250 mL sludge suspension plus sufficient RO water to bring total volume to 500 mL.
- Aeration: Continuous aeration and stirring.
- No. of vessels per concentration (replicates) 5
- No. of vessels per control (replicates): 6
- Biomass loading rate: 1.5 g/L suspended solids in the final test mixture.
- Nitrification inhibitor used (delete if not applicable): none
TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Tap-water purified by reverse osmosis (Milli-RO)
OTHER TEST CONDITIONS
- Adjustment of pH: none.
- Light intensity: not specified.
EFFECT PARAMETERS MEASURED : Dissolved oxygen concentration.
TEST CONCENTRATIONS
- Spacing factor for test concentrations: geometric series (log 0.5)
- Range finding study: Yes
- Test concentrations: 10, 100 and 1000 mg/L, with and without nitrification inhibitor
- Results used to determine the conditions for the definitive study: Yes - Reference substance (positive control):
- yes
- Remarks:
- 3,5-dichlorophenol
- Key result
- Duration:
- 3 h
- Dose descriptor:
- EC50
- Effect conc.:
- > 1 000 mg/L
- Nominal / measured:
- nominal
- Conc. based on:
- test mat.
- Basis for effect:
- inhibition of total respiration
- Remarks on result:
- other: 30% effect at highest level tested
- Duration:
- 3 h
- Dose descriptor:
- EC10
- Effect conc.:
- 139 mg/L
- Nominal / measured:
- nominal
- Conc. based on:
- test mat.
- Basis for effect:
- inhibition of total respiration
- Duration:
- 3 h
- Dose descriptor:
- NOEC
- Effect conc.:
- 100 mg/L
- Nominal / measured:
- nominal
- Conc. based on:
- test mat.
- Basis for effect:
- inhibition of total respiration
- Details on results:
- Based on results of the preliminary test, MTDID 15670 is inhibitory to nitrification. Total respiration was measured in the final test because there was no evidence of bi-phasic or distorted dose-response.
- Results with reference substance (positive control):
- - Results with reference substance valid? yes
- EC50: 12 mg/L The EC50 was within the 2 to 25 mg/L range considered acceptable for the test. - Reported statistics and error estimates:
- Estimation of the EC50 value for the reference substance was based on Weibull analysis using linear maximum likelihood regression with the percentages of respiration inhibition versus the logarithms of the corresponding concentrations of the test item.
Calculation of EC10 values for MTDID 15670 were based on the 3-param. normal Cumulative Distribution Function using a non-linear regression without weighting. An EC50 for MTDID 15670 could not be calculated because effects were below 50%.
The NOEC was determined using Williams Multiple Sequential t-test Procedure (α=0.05, onesided, smaller) to examine statistical significance of respiration rate at each each test substance level v. control. - Validity criteria fulfilled:
- yes
- Remarks:
- Respiration rate in blank controls >20 mg O2/g∙h (29 mg O2/g∙h). Coefficient of variation of control respiration <30% (11%). EC50 for 3,5-DCP in range 2-25 mg/L (12 mg/L)
- Conclusions:
- MTDID 15670 is not inhibitory to sludge at 100 mg/L. 50% effect was not attained up to 1000 mg/L (OECD209)
- Executive summary:
The toxicity of MTDID 15670 to activated sludge was assessed according to the OECD 209 guideline. The test substance was melted, applied to watch glasses, and added directly to test vessels owing to difficulty of working with aqueous solutions. Some effect on nitrification was noted in a preliminary test, however overall effects were small. In the definitive test, 50% effect was not attained at 1000 mg/L. The NOEC was 100 mg/L, and the calculated EC10 was 139 mg/L.
The study was performed in accordance with internationally-accepted test guidelines under GLP. The study is deemed reliable without restriction and suitable for use in Risk Assessment, Classification & Labeling, and PBT Analysis.
Reference
Sample |
Conc. or loading rate (mg/L) |
Respiration rate (mg O2)/ (L∙h) |
Respiration rate (mg O2)/ (g∙h) |
% Inhibition relative to control mean |
Blank controls |
||||
C1 |
0 |
46.54 |
31.03 |
─ |
C2 |
0 |
40.75 |
27.17 |
─ |
C3 |
0 |
37.04 |
24.69 |
─ |
C4 |
0 |
47.14 |
31.43 |
─ |
C5 |
0 |
42.71 |
28.47 |
─ |
C6 |
0 |
49.45 |
32.96 |
─ |
Mean |
─ |
43.94 |
29.29 |
─ |
SD |
─ |
4.62 |
3.08 |
─ |
CV (%) |
─ |
11 |
11 |
─ |
Reference sub.¹ |
||||
ref 1 |
2.0 |
38.97 |
25.98 |
2 |
ref 2 |
4.0 |
27.37 |
18.24 |
31 |
ref 3 |
8.0 |
26.61 |
17.74 |
33 |
ref 4 |
16 |
16.33 |
10.89 |
59 |
Test sub. |
||||
T1a |
10 |
40.03 |
26.69 |
9 |
T1b |
10 |
38.98 |
25.99 |
11 |
T1c |
10 |
34.99 |
23.33 |
20 |
T1d |
10 |
39.95 |
26.63 |
9 |
T1e |
10 |
43.08 |
28.72 |
2 |
Mean T1 |
39.41 |
26.27 |
10 |
|
T2a |
32 |
40.22 |
26.81 |
8 |
T2b |
32 |
39.69 |
26.46 |
10 |
T2c |
32 |
40.16 |
26.77 |
9 |
T2d |
32 |
40.52 |
27.01 |
8 |
T2e |
32 |
43.14 |
28.76 |
2 |
Mean T2 |
40.74 |
27.16 |
7 |
|
T3a |
100 |
39.30 |
26.20 |
11 |
T3b |
100 |
46.52 |
31.01 |
-6 |
T3c |
100 |
45.57 |
30.38 |
-4 |
T3d |
100 |
39.01 |
26.01 |
11 |
T3e |
100 |
40.19 |
26.80 |
9 |
Mean T3 |
42.12 |
28.08 |
4 |
|
T4a |
320 |
41.54 |
27.69 |
5 |
T4b |
320 |
33.31 |
22.21 |
24 |
T4c² |
320 |
# |
# |
# |
T4d |
320 |
28.88 |
19.26 |
34 |
T4e |
320 |
29.58 |
19.72 |
33 |
Mean T4 |
|
33.33 |
22.22 |
24³ |
|
|
|
|
|
T5a |
1000 |
26.32 |
17.54 |
40 |
T5b |
1000 |
36.51 |
24.34 |
17 |
T5c |
1000 |
29.96 |
19.97 |
32 |
T5d |
1000 |
24.57 |
16.38 |
44 |
T5e |
1000 |
35.65 |
23.77 |
19 |
Mean T5 |
|
30.60 |
20.40 |
30³ |
1, reference substance was 3,5-dichlorophenol
2, respiration rate could not be calculated due to non-linearity in oxygen curve
3, Mean significantly different than control
Description of key information
MTDID 15670 is of limited direct toxicity to microorganism (EC10, 139 mg/L, 50% effect not attained at 1000 mg/L maximum loading rate, OECD TG209). However, hydrolysis and biodegradation may release toxic byproducts over longer time scales.
Key value for chemical safety assessment
Additional information
The toxicity of MTDID 15670 to activated sludge was assessed according to the OECD 209 guideline. The test substance was melted, applied to watch glasses, and added directly to test vessels owing to difficulty of working with aqueous solutions. Some effect on nitrification was noted in a preliminary test, however overall effects were small. In the definitive test, 50% effect was not attained at 1000 mg/L. The NOEC was 100 mg/L, and the calculated EC10 was 139 mg/L. MTDID has a hydrolytic half-life too short to be determined at pH 7 and 23 °C. In an OECD 301B test, it could not be ascertained whether MTDID 15670 was inhibitory to degradation, and no meaningful degradation was observed. The expected pathways obtained by QSAR modeling of the hydrolysis product dodecyl ethyl sulfide include mercaptan (thiol) formation. The free sulfhydril groups are known to be toxic to some microorganisms.
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.
![ECHA](/o/diss-blank-theme/images/factsheets/A-REACH/factsheet/echa_logo.png)