Registration Dossier
Registration Dossier
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: 233-069-2 | CAS number: 10028-15-6
- 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

Toxicity to microorganisms
Administrative data
Link to relevant study record(s)
- Endpoint:
- toxicity to microorganisms, other
- Remarks:
- Oxygen Uptake Rate (OUR) and ATP measurement
- Type of information:
- experimental study
- Adequacy of study:
- supporting study
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- study well documented, meets generally accepted scientific principles, acceptable for assessment
- Qualifier:
- no guideline followed
- Principles of method if other than guideline:
- The main goal was to analyze the effect of ozonation on viability of activated sludge in different systems – activated sludge in distilled water and activated sludge in wastewater. Two viability detection methods, oxygen uptake (OUR) rate and adenosine-5’-triphosphate measurement (ATP), were compared.
- GLP compliance:
- no
- Analytical monitoring:
- yes
- Details on sampling:
- - Concentrations: During ozonation experiments, four ozone doses (~15, ~30, ~40 and ~70 mgO2/L) were transferred to the suspension
(initial volume of 1.5 L) in and ozonation reactor.
- Sampling method: 0.5 L out of 2 L was used as an initial or zero-dose
sample. After transferring a certain dose, a sample was taken.
Ozonation time, depending on the transferred ozone dose,
ranged from ~70 to ~120 seconds. - Vehicle:
- no
- Details on test solutions:
- In the experiments a synthetic phenolic wastewater, corresponding by its composition to the oil-shale semi-coking process effluent after the extraction of phenols with butyl acetate (dephenolated process water) was used (Kamenev et al., 2003). The choice of wastewater was based on fact that the purification of the phenolic effluents from the Estonian oil shale industry is still not adequate. Soluble chemical oxygen demand (COD) of the wastewater was of 3100 mgO2/L and 7-day biochemical oxygen demand (BOD7) of 1300 mgO2/L.
- Test organisms (species):
- activated sludge
- Details on inoculum:
- Activated sludge was sampled from a laboratory-scale, continuous stirred tank reactor (CSTR) (volume of 10 L), where it was previously adapted to the phenolic wastewater (approximately 2 years). Hydraulic retention time (HRT) was 2 days and solids retention time (SRT) was between 9 and 10 days. Control and optimization of activated sludge ozonation is based on measurement of mixed liquor volatile suspended solids (MLVSS) and mixed liquor suspended solids (MLSS) by keeping the ratio MLVSS/MLSS constant. The reactor was kept at room temperature (21 ± 1◦C), dissolved oxygen level was maintained between 2–4 mg/L, MLVSS/MLSS was approximately 0.80.
- Test type:
- other: recirculation system
- Water media type:
- other: wastewater and distilled water
- Limit test:
- no
- Total exposure duration:
- 1.5 min
- Remarks on exposure duration:
- Ozonation time, depending on the transferred ozone dose, ranged from ~70 to ~120 seconds.Ha
- Test temperature:
- 21 ± 1 °C
- Dissolved oxygen:
- 2 and 4 mgO2/L
- Nominal and measured concentrations:
- Nominal: (~15, ~30, ~40 and ~70 mgO3/L)
- Details on test conditions:
- TEST SYSTEM
- Test vessel: Batch ozonation experiments were carried out in a 2.6 L cylindrical glass reactor with a conical bottom
- Aeration: After ozonation all samples of AS and AS+WW, were aerated for an hour (dissolved oxygen level was maintained between 2 and 4 mgO2/L) in small batch reactors. Before viability measurement each sample was saturated with oxygen.
- No. of vessels per concentration (replicates): 4 for the activated sludge in distilled water, and 3 replicates for the activated sludge in wastewater.
- No. of vessels per control (replicates):4
TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: see table 1 below
- Particulate matter: MLSS concentration in the experiment of AS ozonation varied from 1.20 to 1.45 g/L and in AS+WW ozonation from 1.40 to 2.40 g/L.
OTHER TEST CONDITIONS
- Adjustment of pH: no
EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Oxygen uptke rate, ATP
TEST CONCENTRATIONS
- Spacing factor for test concentrations: no constant spacing factor: ca 2 - Reference substance (positive control):
- no
- Duration:
- 1.5 min
- Dose descriptor:
- NOEC
- Effect conc.:
- ca. 42 mg/L
- Nominal / measured:
- nominal
- Conc. based on:
- test mat.
- Basis for effect:
- other: oxygen uptake rate
- Remarks on result:
- other: AS + WW
- Key result
- Duration:
- 1.5 min
- Dose descriptor:
- NOEC
- Effect conc.:
- ca. 15 mg/L
- Nominal / measured:
- nominal
- Conc. based on:
- test mat.
- Basis for effect:
- other: oxygen uptake rate
- Remarks on result:
- other: AS only
- Details on results:
- see below
- Results with reference substance (positive control):
- n/a
- Validity criteria fulfilled:
- not applicable
- Remarks:
- no guideline
- Conclusions:
- The NOEC for O3 was determined with 15 mgO3/L in activated sludge, exposure time 1.5 min.
- Executive summary:
This study aimed to analyze the effect of ozonation on viability of activated sludge in different systems – activated sludge in distilled water and activated sludge in wastewater. Ozonation time of the systems, depending on the transferred ozone dose, ranged from ~70 to ~120 seconds. Two viability detection methods, oxygen uptake (OUR) rate and adenosine-5’-triphosphate measurement (ATP), were compared. An immediate viability reduction was detected when only activated sludge was subjected to ozonation, however, ozonation of activated sludge with wastewater, at doses up to 42 mg O3/L did not influence the viability of sludge. A NOEC of 15 mg O3/L was calculated, based on the activated sludge only.
- Endpoint:
- activated sludge respiration inhibition testing
- Data waiving:
- study scientifically not necessary / other information available
- Justification for data waiving:
- the study does not need to be conducted because there is no emission to a sewage treatment plant
- other:
- Justification for type of information:
- Ozone is a gas which will evaporate into the air, or react immediately in the water phase with components such as organic material and metal ions. In view of the short half-life (500 to 5000 s, see Gardoni et al., 2012 in section 5.6), ozone generated for the purpose of water ozonation can safely be expected to completely decompose still within the technical environment (i.e. in the sewerage), before reaching the STP or any water bodies. Therefore, the concentration of ozone in surface waters resulting from technical ozone generation can be considered to be negligible. Performing a test on toxicity to microorganisms is not considered to be required.
Referenceopen allclose all
OUR
The effect of ozone on respiratory activity of activated sludge was determined by measuring the maximum oxygen uptake rate (OUR) expressed in mgO2L−1h−1of sludge treated with various ozone doses (15–70 mgO3L−1). For better comparison of the OUR results, the specific oxygen uptake rate (SOUR), expressed in mgO2gMLVSS−1h−1, was calculated by dividing OUR by MLVSS, as it depends on the concentration of MLVSS. For calculation of exogenous SOUR (SOURex) both endogenous and total SOUR (SOURend and SOURtot, respectively), were measured. SOURex, used for evaluation of sludge viability, was calculated by subtracting SOURend from SOURtot. SOURend is defined as the oxygen consumption in the absence of external substrate (Dawes and Ribbons, 1962). SOURex is oxygen consumption caused by addition of external biodegradable substrate. Initial SOURend of the studied sludge varied between 8 and 12.3 mgO2gMLVSS−1h−1(Fig. 1). Depending on the ozone dose applied, the measured SOURend, without the addition of external substrate, increased up to 1.8 times compared to initial SOURend (Fig. 1). Ozone is known to be a strong cell lyses agent and thereby reduces the number of viable micro-organisms in activated sludge. If the number of viable micro-organisms is reduced, the SOURend should also be reduced, as it depends on the concentration of oxygen consuming cells which use intracellular reserve material for maintenance purposes (Dawes and Ribbons, 1962).
To determine any correlation between the soluble COD generated during ozonation and SOURend, ∆COD (COD – COD0) was plotted against ∆SOURend(SOURend-SOURend0) (Fig. 2).
ATP
Initial specific ATP concentration (SATP) of activated sludge (ATP concentration in zero-dose activated sludge) used for ozonation ranged from 2.30 to 2.80 mgATP gMLVSS−1. SATP concentration, depending on the applied ozone dose, ranged from 1.05 to 1.98 mgATP·gMLVSS−1. Reduction of SATP content in activated sludge due to the ozonation, expressed as relative SATP (SATP/SATP0), is presented in Figure 3.
Description of key information
The study does not need to be conducted, as ozone is unlikely to stay in the water phase, hence, is not expected that the applied ozone will reach a sewage plant. Ozone is unstable, evaporates into the air, and/or reacts with other molecules due to its oxidizing characteristics. Therefore, no PNEC for microorganisms was derived. A supporting study is attached, analyzing the short term toxicity (about 1.5 min exposure) of ozone to activated sludge.
Key value for chemical safety assessment
Additional information
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.
