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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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: 242-354-0 | CAS number: 18472-51-0
- 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
Hydrolysis
Administrative data
Link to relevant study record(s)
- Endpoint:
- hydrolysis
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- 1998
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- other: GLP study according to guideline
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 111 (Hydrolysis as a Function of pH)
- Deviations:
- yes
- Remarks:
- Because the test substance forms sparingly soluble precipitates with the buffer ions recommended in the Guideline, test was run in aqueous solutions. The pH was adjusted using gluconic acid or NaOH.
- Qualifier:
- according to guideline
- Guideline:
- EU Method C.7 (Degradation: Abiotic Degradation: Hydrolysis as a Function of pH)
- Version / remarks:
- cited as 92/69/EEC C.07
- Deviations:
- yes
- Remarks:
- Because the test substance forms sparingly soluble precipitates with the buffer ions recommended in the Guideline, test was run in aqueous solutions. The pH was adjusted using gluconic acid or NaOH.
- Principles of method if other than guideline:
- Only preliminary test performed
- GLP compliance:
- yes (incl. QA statement)
- Remarks:
- Degussa AG, Zentrale Forschungseinrichtungen Chromatographie und Organische Analytik
- Radiolabelling:
- no
- Analytical monitoring:
- yes
- Details on sampling:
- - Sampling intervals for the parent/transformation products: At each day (1, 2, 3, 4, and 5 d) sample solutions together with calibration solutions (Chlorhexidine and p-Chloroaniline) were measured.
- Details on test conditions:
- TEST SYSTEM
- Details of traps for volatile, if any: Chlorhexidine is not volatile from aqueous solutions
- Is there any indication of the test material adsorbing to the walls of the test apparatus? no
TEST MEDIUM
- Preparation of test medium: Ca. 5.0 g test substance (Chlorhexidine gluconate solution 20%) were transferred into 100 mL volumetric flask, 90 mL water were added, target pH was adjusted using gluconic acid (prepared as a 10% solution of glucono-d-lactone) or 0.1 M sodium hydroxyde solution to pH 4.0, 7.0, and 9.0, and the flasks were filled to the volume with water.
- Test concentrations: ca. 10 g/L
- Temperature: 50°C
- Identity and concentration of co-solvent: No co-solvent was used
OTHER TEST CONDITIONS
- Adjustment of pH: After each day, pH of the 3 test solutions were corrected if necessary. The changes in volume by adding small quantities of dilute solutions of gluconic acid or sodium hydroxyde were below 1% of the total volume - Duration:
- 5 d
- pH:
- 4
- Duration:
- 5 d
- pH:
- 7
- Duration:
- 5 d
- pH:
- 9
- Number of replicates:
- 1
- Positive controls:
- no
- Remarks:
- Reference substance not required by the Guideline
- Preliminary study:
- In the preliminary test, no significant hydrolysis was observed at all pH values. Changes in concentrations were below 10%.
- Transformation products:
- yes
- No.:
- #1
- % Recovery:
- > 90
- Temp.:
- 50 °C
- Duration:
- 5 d
- pH:
- 4
- Temp.:
- 25 °C
- DT50:
- > 1 yr
- pH:
- 7
- Temp.:
- 25 °C
- DT50:
- > 1 yr
- pH:
- 9
- Temp.:
- 25 °C
- DT50:
- > 1 yr
- Details on results:
- Degradation: < 10% after 5 days at pH 4, 7 and 9 (50°C)
- Validity criteria fulfilled:
- yes
- Conclusions:
- It can be concluded that under environmental conditions the hydrolysis half-life time of Chlorhexidine base is more than 1 year.
Reference
Analytical results for the preliminary test of Chlorhexidine (CHD), p‑Chloroaniline (PCA) and unknown inpurities (calculated as CHD):
pH 4.0:
Time |
start |
day 1 |
day 2 |
day 3 |
day 4 |
day 5 |
CHD [%] |
0.50 |
0.53 |
0.54 |
0.52 |
0.58 |
0.54 |
PCA [%] |
n.d. |
0.0003 |
0.0002 |
0.0004 |
0.0004 |
0.0005 |
Impurities [mg/kg] |
75 |
85 |
81 |
102 |
106 |
99 |
pH 7.0:
Time |
start |
day 1 |
day 2 |
day 3 |
day 4 |
day 5 |
CHD [%] |
0.55 |
0.54 |
0.52 |
0.53 |
0.54 |
0.52 |
PCA [%] |
0.0002 |
n.d. |
n.d. |
0.0002 |
0.0002 |
0.0003 |
Impurities [mg/kg] |
85 |
88 |
89 |
78 |
90 |
86 |
pH 9.0:
Time |
start |
day 1 |
day 2 |
day 3 |
day 4 |
day 5 |
CHD [%] |
0.56 |
0.53 |
0.55 |
0.53 |
0.54 |
0.53 |
PCA [%] |
0.0001 |
0.0002 |
0.0001 |
0.0003 |
0.0003 |
0.0003 |
Impurities [mg/kg] |
82 |
89 |
110 |
118 |
131 |
138 |
The results reveal that the concentration of Chlorhexidine remains constant at all pH values over the test period of 5 days. The concentrations do not change by more than 10% during the test period. The preliminary test was sufficient.
In the HPLC column, separation of the base Chlorhexidine and Gluconate is expected. As only Chlorhexidine base was detected, the test reveals that the base is not hydrolyzable. Due to the molecular structure, hydrolysis of gluconic acid is not expected.
Description of key information
Under environmental conditions the hydrolysis half-life of Chlorhexidine base is more than 1 year.
Key value for chemical safety assessment
- Half-life for hydrolysis:
- 1 yr
- at the temperature of:
- 20 °C
Additional information
Hydrolysis of Chlorhexidine digluconate has been performed according to OECD Guideline 111 and EEC-Guideline C.07. No significant hydrolysis was observed at all pH values.
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.