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EC number: 231-668-3 | CAS number: 7681-52-9
- 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
Toxicological Summary
- Administrative data
- Workers - Hazard via inhalation route
- Workers - Hazard via dermal route
- Workers - Hazard for the eyes
- Additional information - workers
- General Population - Hazard via inhalation route
- General Population - Hazard via dermal route
- General Population - Hazard via oral route
- General Population - Hazard for the eyes
- Additional information - General Population
Administrative data
Workers - Hazard via inhalation route
Systemic effects
Long term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 1.55 mg/m³
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 2
- Modified dose descriptor starting point:
- NOAEC
- Value:
- 0.5
- AF for dose response relationship:
- 1
- AF for differences in duration of exposure:
- 2
- AF for interspecies differences (allometric scaling):
- 1
- AF for other interspecies differences:
- 1
- Justification:
- Human data
- AF for intraspecies differences:
- 1
- AF for the quality of the whole database:
- 1
- AF for remaining uncertainties:
- 1
Acute/short term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 3.1 mg/m³
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- DNEL derivation method:
- other: STEL derived by the SCOEL
- Overall assessment factor (AF):
- 1
- Modified dose descriptor starting point:
- other:
Local effects
Long term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 1.55 mg/m³
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 2
- Dose descriptor:
- NOAEC
- AF for dose response relationship:
- 1
- AF for differences in duration of exposure:
- 2
- AF for interspecies differences (allometric scaling):
- 1
- AF for other interspecies differences:
- 1
- AF for intraspecies differences:
- 1
- AF for the quality of the whole database:
- 1
- AF for remaining uncertainties:
- 1
Acute/short term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 3.1 mg/m³
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- DNEL derivation method:
- other: STEL derived by the SCOEL
- Overall assessment factor (AF):
- 1
- Dose descriptor starting point:
- other:
Workers - Hazard via dermal route
Systemic effects
Long term exposure
- Hazard assessment conclusion:
- no hazard identified
Acute/short term exposure
- Hazard assessment conclusion:
- low hazard (no threshold derived)
DNEL related information
Local effects
Long term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 0.5 % in mixture (weight basis)
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- DNEL derivation method:
- other: Qualitative approach based on Human data
- Overall assessment factor (AF):
- 1
- Dose descriptor:
- other: NOAEL
Acute/short term exposure
- Hazard assessment conclusion:
- low hazard (no threshold derived)
Workers - Hazard for the eyes
Local effects
- Hazard assessment conclusion:
- low hazard (no threshold derived)
Additional information - workers
Acute /short-term DNELs (dermal)
A DNEL for acute/short-term, dermal exposure will not be derived for the following reasons:
- The acute toxicity of corrosive substances is more related to concentration then to dose,
extrapolation from data obtained with hypochlorite solutions to a fictive 100% sodium
hypochlorite is not possible.
- According to chapter R8 of the ECHA “Guidance on information requirements and chemical
safety assessment” a DNEL for acute toxicity should be derived if an acute toxicity hazard
(leading to C&L) has been identified. Sodium Hypochlorite is not classified regarding acute
dermal toxicity.
- According to chapter R8 of the ECHA “Guidance on information requirements and chemical
safety assessment” a DNEL for acute toxicity should be derived if there is a potential for high
peak exposures, for instance when sampling or connecting/disconnecting vessels. This is not
the case for sodium hypochlorite. High peak exposures do not occur during the
manufacturing or use.
- The risk for dermal corrosion/irritation will be evaluated qualitatively (see repeated dose
toxicity).
Acute /short-term DNELs (inhalation)
Being an anion, ClO- will not volatilize from aqueous solutions. Thusno sodium hypochlorite as such can be present in the atmosphere except in the case in which an aerosol is formed. This does not occur during the production however workers can be exposed to chlorine atmosphere during the production of sodium hypochlorite or during the sampling or connecting/disconnecting vessels.
In Appendix R.8-13 of the Guidance on information requirements and chemical safety assessment Chapter R.8:Characterisation of dose [concentration]-response for human health (May 2008, ECHA) it is noted that:
‘When an EU IOEL exists the registrant may, under conditions as described below, use the IOEL in place of developing a DNEL. A registrant is allowed to use an IOEL as a DNEL for the same exposure route andduration, unless new scientific information that he has obtained in fulfilling his obligations under REACH doesnot support the use of the IOEL for this purpose. This could be because the information obtained is more recentthan the information that was used to support setting the IOEL at EU level and because it leads to another valuebeing derived which requires different risk management measures (RMMs) and operational conditions (OCs) ’.
The SCOEL has derived a STEL(15 min)forchlorine(SEG/SUM/76final,December1998) based on the fact that a constant exposure to 0.5 ppm (1.5 mg/m3) has been shown to be without effect in two human studies and also in rhesus monkeys whereas there is a clear evidence of irritation at 1.0 ppm (2.95 mg/m3). On this basis, the SCOEL considers that occupational exposure levels should not exceed 0.5 ppm.
The STEL derived by the SCOEL will be used as DNEL for acute inhalation exposure: 0.5 ppm of chlorinefor an exposure duration of 15 minutes.This value is equal 3.1mg/m3hypochlorite taking molecular ratio and molecular weight into account.
DNELacute short , inhalation= 3.1 mg/m3(local and systemic effects)
Long-term DNEL (dermal)
Active chlorine will not pass the skin and will not be transported via the blood to become systemically available, therefore no systemic toxicity is expected after dermal exposure to hypochlorite. A qualitative approach based on local effects of hypochlorite is appropriate
For local effects after repeated dose dermal exposure a qualitative risk assessment will be
performed. The study by Cotter et al. (see IUCLID5 section 7.12) provides indication that
continuous exposure towards 0.5% hypochlorite concentration is about the threshold for
effects on basal cell viability (Cotter, 1985). The NOAEL is 0.1 % and the LOAEL is 0.5 %, based on a 15 % decrease of basal cell viability. As this decrease is marginal, and as human case reports supports a NOAEL of 0.5 %, as specified in the EU RAR, a NOAEL for local effects after repeated dermal exposure of 0.5% is thus established. A concentration of 0.5% is equivalent to 6.8 g/L (with a density of 1.3 g/mL and a correction factor of 1.05 (74.5/71) convert the doses given in active chlorine to NaOCl).
Long-term DNEL (inhalation)
Because the effects appear to be related to concentration in the air and not to the duration of exposure, the SCOEL does not recommend an 8-hour TWA. However, by a conservative approach, a long termDNEL inhalation will be derivedbased on the data that is available from human volunteer studies, as follows:
- 0.5 ppm (NOEL)/1.0 ppm (LOEL) following 8-hour exposure of chlorine gas in normal subjects (Rotman et al 1983);
- 0.4 ppm (NOEL)/1.0 ppm (LOEL) following 1-hour exposure of chlorine gas in hyper-responsive subjects (D'Alessandro et al 1996 )
- 0.5 ppm (NOEL) following 3 x 6-hour exposure of chlorine gas in young health subjects (Emmen & Hoogendijk 1997 - "EuroChlor").
From this data, a NOEL of 0.5 ppm is selected and the following assessment factors will be applied as follows:
- 1 for the interspecies variation as the data are human data,
- 1 for the Intraspecies differences as a study in hyper-responsive subjects showed no significant difference in sensitivity),
- 2 for the exposure duration sincethe animal and human studies showed that there is no substantial difference in N(L)OAECs following acute, subacute and/or chronic exposure by inhalation. This is supported by the fact that the toxic effects of chlorine are considered concentration- rather dose-dependent,
- 1 for the dose-response reliability,
- 1 for the quality of whole database,
DNEL = 0.5 x 1/2 = 0.25 ppm(chlorine)
This value is equal 1.55 mg/m3 hypochlorite taking molecular ration and molecular weight into account.
DNEL long-term inhalation = 1.55 mg/m3 (local and systemic effects)General Population - Hazard via inhalation route
Systemic effects
Long term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 1.55 mg/m³
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 2
- Modified dose descriptor starting point:
- NOAEC
- AF for dose response relationship:
- 1
- AF for differences in duration of exposure:
- 2
- AF for interspecies differences (allometric scaling):
- 1
- AF for other interspecies differences:
- 1
- AF for intraspecies differences:
- 1
- AF for the quality of the whole database:
- 1
- AF for remaining uncertainties:
- 1
Acute/short term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 3.1 mg/m³
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- Overall assessment factor (AF):
- 1
- Modified dose descriptor starting point:
- NOAEC
Local effects
Long term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 1.55 mg/m³
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 2
- Dose descriptor:
- NOAEC
- AF for dose response relationship:
- 1
- AF for differences in duration of exposure:
- 2
- AF for interspecies differences (allometric scaling):
- 1
- AF for other interspecies differences:
- 1
- AF for intraspecies differences:
- 1
- AF for the quality of the whole database:
- 1
- AF for remaining uncertainties:
- 1
Acute/short term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 3.1 mg/m³
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- DNEL derivation method:
- other: STEL derived by the SCOEL
- Overall assessment factor (AF):
- 1
- Dose descriptor starting point:
- other:
General Population - Hazard via dermal route
Systemic effects
Long term exposure
- Hazard assessment conclusion:
- no hazard identified
Acute/short term exposure
- Hazard assessment conclusion:
- low hazard (no threshold derived)
DNEL related information
Local effects
Long term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 0.5 % in mixture (weight basis)
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- DNEL derivation method:
- other:
- Overall assessment factor (AF):
- 1
- Dose descriptor:
- other: NOAEL
Acute/short term exposure
- Hazard assessment conclusion:
- low hazard (no threshold derived)
General Population - Hazard via oral route
Systemic effects
Long term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 0.26 mg/kg bw/day
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 200
- Modified dose descriptor starting point:
- NOAEL
- Value:
- 50
- AF for dose response relationship:
- 1
- AF for differences in duration of exposure:
- 2
- AF for interspecies differences (allometric scaling):
- 4
- AF for other interspecies differences:
- 2.5
- AF for intraspecies differences:
- 10
- AF for the quality of the whole database:
- 1
- AF for remaining uncertainties:
- 1
Acute/short term exposure
- Hazard assessment conclusion:
- low hazard (no threshold derived)
DNEL related information
General Population - Hazard for the eyes
Local effects
- Hazard assessment conclusion:
- low hazard (no threshold derived)
Additional information - General Population
Acute /short-term DNELs (dermal)
A DNEL for acute/short-term, dermal exposure will not be derived for the following reasons:
- The acute toxicity of corrosive substances is more related to concentration then to dose,
extrapolation from data obtained with hypochlorite solutions to a fictive 100% sodium
hypochlorite is not possible.
- According to chapter R8 of the ECHA “Guidance on information requirements and chemical
safety assessment” a DNEL for acute toxicity should be derived if an acute toxicity hazard
(leading to C&L) has been identified. Sodium Hypochlorite is not classified regarding acute
dermal toxicity.
- According to chapter R8 of the ECHA “Guidance on information requirements and chemical
safety assessment” a DNEL for acute toxicity should be derived if there is a potential for high
peak exposures, for instance when sampling or connecting/disconnecting vessels. This is not
the case for sodium hypochlorite. High peak exposures do not occur during the
manufacturing or use.
- The risk for dermal corrosion/irritation will be evaluated qualitatively (see repeated dose
toxicity).
Acute /short-term DNELs (inhalation)
Being an anion, ClO- will not volatilize from aqueous solutions. The minute fraction of HOCl present in commercial solutions has a very low volatility. Gaseous chlorine can be released from a sodium hypochlorite solution only in accidental case by mixing with strong acids. Therefore, exposure does not comprise inhalation exposure, except in the case in which an aerosol is formed as for the trigger sray bottles for household cleaners.
The SCOEL has derived a STEL(15 min) for chlorine(SEG/SUM/76final,December1998) based on the fact that a constant exposure to 0.5 ppm (1.5 mg/m3) has been shown to be without effect in two human studies and also in rhesus monkeys whereas there is a clear evidence of irritation at 1.0 ppm (2.95 mg/m3). On this basis, the SCOEL considers that occupational exposure levels should not exceed 0.5 ppm.
The STEL derived by the SCOEL will be used as DNEL for acute inhalation exposure: 0.5 ppm of chlorinefor an exposure duration of 15 minutes.This value is equal 3.1mg/m3hypochlorite taking molecular ratio and molecular weight into account.
DNELacute short , inhalation= 3.1 mg/m3(local and systemic effects)
Acute /short-term DNELs (oral)
A DNEL for acute/short-term, oral exposure will not be derived for the following reasons:
- Effects of accidental ingestion of domestic sodium hypochlorite bleaches (strongly diluted
hypochlorite solutions only) are not expected to lead to severe or permanent damage of the
gastrointestinal tract as recovery is rapid and without any permanent health consequences,
based on human data.
- The acute toxicity of corrosive substances is more related to concentration then to dose,
extrapolation from data obtained with hypochlorite solutions to a fictive 100% sodium
hypochlorite is not possible.
- According to chapter R8 of the ECHA “Guidance on information requirements and chemical
safety assessment” a DNEL for acute toxicity should be derived if an acute toxicity hazard
(leading to C&L) has been identified. Theoretical pure sodium hypochlorite should be
classified as “harmful for ingestion” (Xn, R22) on the basis of the oral LD50 data. However,
the effects noted can be considered of secondary nature and caused by local tissue damage
due the substance corrosive properties. This classification does not apply to solutions as
their concentration is always below 25%. The acute toxicity of corrosive substances is more
related to concentration then to dose, and extrapolation from data obtained from using a
hypochlorite solution to a fictive 100% sodium hypochlorite is not possible.
As the highest concentrations of hypochlorite solutions industrially produced and marketed
are about 15%, and solutions marketed for consumer use are typically 5% or less, it can be
concluded from the data presented that hypochlorite solutions are of low acute oral toxicity.
This is confirmed by the available data from human accidents, where the few deaths that
have occurred after hypochlorite ingestion are mostly attributable to aspiration pneumonia.
- According to chapter R8 of the ECHA “Guidance on information requirements and chemical
safety assessment” a DNEL for acute toxicity should be derived if there is a potential for high
peak exposures. This is not the case during the use of sodium hypochlorite.
Long-term DNEL (oral)
The study by Hasegawa (1986) was chosen as key study for the derivation of the DNEL,
although usually a value from a chronic study is preferred over a value from a sub-chronic
study. In the Hasegawa study the dosing levels include “no-effect” and “effect” levels. Thus, a
NO(A)EL and a LO(A)EL could be distinguished. In the NTP study (1992) as in all other
studies, dose levels were maximum levels, the highest dose level is a NO(A)EL and there
was no LOAEL. Basically, when selecting a NOAEL for risk assessment. One should base it
on the highest NOAEL which lower then the lowest LOAEL level (which incorporates in its
evaluation all relevant – i.e. most sensitive - parameters).
The NOELlong-term, oral, determined in the Hasegawa study (rat, 90 day drinking water study)
was 50 mg/kg bw/day (see section 5.6.1.1). An assessment factor of 4 for the interspecies
variation (allometric scaling from rat to human), an additional 2.5 factor for other interspecies
differences, a factor of 2 for extrapolation from subchronic to chronic exposure plus a factor
of 10 for intraspecies differences (general population) was applied resulting in a final
assessment factor of 200. In addition a correction factor of 1.05 (74.5/71) has to be applied
to convert the doses given in active chlorine to NaOCl.
DNELlong-term, oral= 0.26 mg/kg bw/day.
Long-term DNEL (dermal)
Active chlorine will not pass the skin and will not be transported via the blood to become systemically available, therefore no systemic toxicity is expected after dermal exposure to hypochlorite. A qualitative approach based on local effects of hypochlorite is appropriate
For local effects after repeated dose dermal exposure a qualitative risk assessment will be
performed. The study by Cotter et al. (see IUCLID5 section 7.12) provides indication that
continuous exposure towards 0.5% hypochlorite concentration is about the threshold for
effects on basal cell viability (Cotter, 1985). The NOAEL is 0.1 % and the LOAEL is 0.5 %, based on a 15 % decrease of basal cell viability. As this decrease is marginal, and as human case reports supports a NOAEL of 0.5 %, as specified in the EU RAR, a NOAEL for local effects after repeated dermal exposure of 0.5% is thus established. A concentration of 0.5% is equivalent to 6.8 g/L (with a density of 1.3 g/mL and a correction factor of 1.05 (74.5/71) convert the doses given in active chlorine to NaOCl).
Long-term DNEL (inhalation)
Because the effects appear to be related to concentration in the air and not to the duration of exposure, the SCOEL does not recommend an 8-hour TWA. However, by a conservative approach, a long termDNEL inhalation will be derivedbased on the data that is available from human volunteer studies, as follows:
- 0.5 ppm (NOEL)/1.0 ppm (LOEL) following 8-hour exposure of chlorine gas in normal subjects (Rotman et al 1983);
- 0.4 ppm (NOEL)/1.0 ppm (LOEL) following 1-hour exposure of chlorine gas in hyper-responsive subjects (D'Alessandro et al 1996 )
- 0.5 ppm (NOEL) following 3 x 6-hour exposure of chlorine gas in young health subjects (Emmen & Hoogendijk 1997 - "EuroChlor").
From this data, a NOEL of 0.5 ppm is selected and the following assessment factors will be applied as follows:
- 1 for the interspecies variation as the data are human data,
- 1 for the Intraspecies differences as a study in hyper-responsive subjects showed no significant difference in sensitivity,
- 2 for the exposure duration sincethe animal and human studies showed that there is no substantial difference in N(L)OAECs following acute, subacute and/or chronic exposure by inhalation. This is supported by the fact that the toxic effects of chlorine are considered concentration- rather dose-dependent,
- 1 for the dose-response reliability,
- 1 for the quality of whole database,
DNEL = 0.5 x 1/2 = 0.25 ppm (chlorine)
This value is equal 1.55 mg/m3 hypochlorite taking molecular ration and molecular weight into account.
DNEL long-term inhalation = 1.55 mg/m3 (local and systemic effectsInformation 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.