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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
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EC number: 233-162-8 | CAS number: 10049-04-4
- 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
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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:
- 0.6 mg/m³
- Most sensitive endpoint:
- repeated dose toxicity
- Route of original study:
- Oral
DNEL related information
- DNEL derivation method:
- other: EFSA, Weterings et al., 2016 and ECHA REACH guidance
- Overall assessment factor (AF):
- 0.05
- Dose descriptor starting point:
- other: Tolerable Daily Intake (TDI)
- Value:
- 4 µg/kg bw/day
- Modified dose descriptor starting point:
- NOAEC
- Value:
- 0.03 mg/m³
- Explanation for the modification of the dose descriptor starting point:
Perchlorate Tolerable Daily Intake (TDI) = 4 µg/kg bw/day (Weterings et al., 2016).
NOAEC (NaClO3) = (perchlorate TDI x worker bodyweight / worker respiratory volume) x Molecular Weight NaClO3 / Molecular Weight ClO4 = (0.004 mg/kg bw/day x 70 kg / 10 m3/day) x 106.44 / 99.45 = 0.03 mg/m3
- AF for dose response relationship:
- 0.1
- Justification:
- According to EFSA CONTAM Panel, a factor of 10 was applied to account for the lower potency of chlorate compared to perchlorate for the inhibition of iodine uptake in humans (critical effect identified by EFSA).
- AF for differences in duration of exposure:
- 1
- Justification:
- EFSA CONTAM Panel considered the inhibition of thyroid iodine uptake as the critical effect for the chronic hazard characterisation. No further safety factor was considered for duration of exposure.
- AF for interspecies differences (allometric scaling):
- 1
- Justification:
- The study was performed in human volunteers (Greer et al., 2002).
- AF for other interspecies differences:
- 1
- Justification:
- The study was performed in human volunteers (Greer et al., 2002).
- AF for intraspecies differences:
- 0.5
- Justification:
- The study was performed in human volunteers representing general population. Also, the starting point corresponds to a TDI value, intended to general population (an AF of 4 had already been applied by the EFSA CONTAM Panel to the BMDL value to derive the TDI value for perchlorate). As the workers are a more restricted population, a safety factor of 0.5 can be applied to the initial TDI.
- AF for the quality of the whole database:
- 1
- Justification:
- The study on inhibition of iodine uptake by perchlorate in human volunteers (Greer et al., 2002) was considered appropriate and was validated by EFSA CONTAM Panel.
- AF for remaining uncertainties:
- 1
- Justification:
- No remaining uncertainties were identified.
Acute/short term exposure
- Hazard assessment conclusion:
- no hazard identified
DNEL related information
Local effects
Long term exposure
- Hazard assessment conclusion:
- no hazard identified
Acute/short term exposure
- Hazard assessment conclusion:
- no hazard identified
DNEL related information
Workers - Hazard via dermal route
Systemic effects
Long term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 4.2 mg/kg bw/day
- Most sensitive endpoint:
- repeated dose toxicity
- Route of original study:
- Oral
DNEL related information
- DNEL derivation method:
- other: EFSA, Weterings et al., 2016 and ECHA REACH guidance
- Overall assessment factor (AF):
- 0.05
- Dose descriptor starting point:
- other: Tolerable Daily Intake (TDI)
- Value:
- 4 µg/kg bw/day
- Modified dose descriptor starting point:
- NOAEL
- Value:
- 0.21 mg/kg bw/day
- Explanation for the modification of the dose descriptor starting point:
Perchlorate Tolerated Daily Intake (TDI) = 4 µg/kg bw/day (Weterings et al., 2016).
A maximum dermal absorption value of approximately 2% was found in an in vitro dermal absorption study with human skin at a low dose of 150 µg/cm².
NOAEL (NaClO3) = perchlorate TDI / human dermal absorption x Molecular Weight NaClO3 / Molecular Weight ClO4 = 0.004 mg/kg bw/day / 0.02 x 106.44 / 99.45 = 0.21 mg/kg bw/day
- AF for dose response relationship:
- 0.1
- Justification:
- According to EFSA CONTAM Panel, a factor of 10 was applied to account for the lower potency of chlorate compared to perchlorate for the inhibition of iodine uptake in humans (critical effect identified by EFSA).
- AF for differences in duration of exposure:
- 1
- Justification:
- EFSA CONTAM Panel considered the inhibition of thyroid iodine uptake as the critical effect for the chronic hazard characterisation. No further safety factor was considered for duration of exposure.
- AF for interspecies differences (allometric scaling):
- 1
- Justification:
- The study was performed in human volunteers (Greer et al., 2002).
- AF for other interspecies differences:
- 1
- Justification:
- The study was performed in human volunteers (Greer et al., 2002).
- AF for intraspecies differences:
- 0.5
- Justification:
- The study was performed in human volunteers representing general population. Also, the starting point corresponds to a TDI value, intended to general population (an AF of 4 had already been applied by the EFSA CONTAM Panel to the BMDL value to derive the TDI value for perchlorate). As the workers are a more restricted population, a safety factor of 0.5 can be applied to the initial TDI.
- AF for the quality of the whole database:
- 1
- Justification:
- The study on inhibition of iodine uptake by perchlorate in human volunteers (Greer et al., 2002) was considered appropriate and was validated by EFSA CONTAM Panel.
- AF for remaining uncertainties:
- 1
- Justification:
- No remaining uncertainties were identified.
Acute/short term exposure
- Hazard assessment conclusion:
- no hazard identified
DNEL related information
Local effects
Long term exposure
- Hazard assessment conclusion:
- no hazard identified
Acute/short term exposure
- Hazard assessment conclusion:
- no hazard identified
Workers - Hazard for the eyes
Local effects
- Hazard assessment conclusion:
- no hazard identified
Additional information - workers
Risks for public health related to the presence of chlorate in food was assessed by EFSA CONTAM Panel in 2015 1. Inhibition of iodine uptake in humans was identified as the critical effect for chronic exposure to chlorate and perchlorate. A tolerable daily intake (TDI) was set by read-across from a TDI derived for this effect for perchlorate.
The established TDI was based on a BMDL05 for thyroid iodine uptake inhibition by perchlorate from a study performed in human volunteers (Greer et al., 2002), multiplied by a an overall assessment factor of 4.
When comparing the NOAEL and LOAEL for thyroid follicular cell hypertrophy in rats, perchlorate is about 10 times more potent than chlorate. Therefore, the CONTAM Panel established a TDI for chlorate of 3 μg/kg bw/day, based on the TDI established for perchlorate (0.3 μg/kg bw/day) and by multiplying by a factor of 10 for the difference in potency between the two substances.
Then, Weterings et al.2 demonstrated that the physiological intraindividual variation in iodine uptake is much larger than 5%. Therefore, a Benchmark Response (BMR) of 20% was proposed for benchmark dose analysis of human thyroidal iodine uptake data, to take the inherent variation in relative thyroidal uptake of radioactive iodine data into account. The derived TDI from the BMDL20 for perchlorate was then 4 µg/kg bw/day, which is the starting point used to calculate sodium chlorate DNELs.
Worker - DNEL inhalation long-term systemic toxicity
Modified starting point:
Route to route extrapolation was done from the TDI for perchlorate to obtain a NOAEC for sodium chlorate:
NOAEC (NaClO3) = (perchlorate TDI x worker bodyweight / worker respiratory volume) x Molecular Weight NaClO3 / Molecular Weight ClO4 = (0.004 mg/kg bw/day x 70 kg / 10 m3/day) x 106.44 / 99.45 = 0.03 mg/m3
Assessment factors:
As applied by the EFSA CONTAM Panel, an assessment factor of 0.1 was used to take into account the 10 times lower potency of chlorate compared to perchlorate towards thyroid function.
Also, the TDI is calculated for the general population while worker population corresponds to a more restricted population. According to ECHA guidance Chapter R.8, an assesment factor of 10 is generally used to take into account intraspecies variability in general population while an assessment factor of 5 is generally used for workers. Therefore, the assessment factor for intraspecies variability in workers was reduced by a factor of 0.5.
The global assessment factor applied to the modified starting point was therefore 0.05.
DNEL inhalation long-term systemic toxicity = 0.03 mg/m3 / 0.05 = 0.6 mg/m3
Worker - DNEL dermal long-term systemic toxicity
Modified starting point:
Route to route extrapolation was done from the TDI for perchlorate to obtain a NOAEL for sodium chlorate:
A maximum dermal absorption value of approximately 2% was found in an in vitro dermal absorption study with human skin at a low dose of 150 µg/cm².
NOAEL (NaClO3) = perchlorate TDI / human dermal absorption x Molecular Weight NaClO3 / Molecular Weight ClO4 = 0.004 mg/kg bw/day / 0.02 x 106.44 / 99.45 = 0.21 mg/kg bw/day
Assessment factors:
As applied by the EFSA CONTAM Panel, an assessment factor of 0.1 was used to take into account the 10 times lower potency of chlorate compared to perchlorate towards thyroid function.
Also, the TDI is calculated for the general population while worker population corresponds to a more restricted population. According to ECHA guidance Chapter R.8, an assesment factor of 10 is generally used to take into account intraspecies variability in general population while an assessment factor of 5 is generally used for workers. Therefore, the assessment factor for intraspecies variability in workers was reduced by a factor of 0.5.
The global assessment factor applied to the modified starting point was therefore 0.05.
DNEL dermal long-term systemic toxicity = 0.21 mg/kg bw/day / 0.05 = 4.2 mg/kg bw/day
1 EFSA CONTAM Panel (EFSA Panel on Contaminants in the Food Chain), 2015. Scientific Opinion on risks for public health related to the presence of chlorate in food. EFSA Journal 2015;13(6):4135, 103 pp. doi:10.2903/j.efsa.2015.4135
2 Weterings PJ, Loftus C, Lewandowski TA. Derivation of the critical effect size/benchmark response for the dose-response analysis of the uptake of radioactive iodine in the human thyroid. Toxicol Lett. 2016 Aug 22;257:38-43.
doi: 10.1016/j.toxlet.2016.06.004. PMID: 27268963
General Population - Hazard via inhalation route
Systemic effects
Long term exposure
- Hazard assessment conclusion:
- no hazard identified
Acute/short term exposure
- Hazard assessment conclusion:
- no hazard identified
DNEL related information
Local effects
Long term exposure
- Hazard assessment conclusion:
- no hazard identified
Acute/short term exposure
- Hazard assessment conclusion:
- no hazard identified
DNEL related information
General Population - Hazard via dermal route
Systemic effects
Long term exposure
- Hazard assessment conclusion:
- no hazard identified
Acute/short term exposure
- Hazard assessment conclusion:
- no hazard identified
DNEL related information
Local effects
Long term exposure
- Hazard assessment conclusion:
- no hazard identified
Acute/short term exposure
- Hazard assessment conclusion:
- no hazard identified
General Population - Hazard via oral route
Systemic effects
Long term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 0.043 mg/kg bw/day
- Most sensitive endpoint:
- repeated dose toxicity
- Route of original study:
- Oral
DNEL related information
- DNEL derivation method:
- other: EFSA, Weterings et al., 2016 and ECHA REACH guidance
- Overall assessment factor (AF):
- 0.1
- Dose descriptor starting point:
- other: Tolerable Daily Intake (TDI)
- Value:
- 4 µg/kg bw/day
- Modified dose descriptor starting point:
- NOAEL
- Value:
- 4.3 µg/kg bw/day
- Explanation for the modification of the dose descriptor starting point:
The initial study was performed in human volunteers by oral route with perchlorate. The only modification needed is about the difference in molecular weight between perchlorate and sodium chlorate.
TDI (NaClO3) = TDI perchlorate x MW NaClO3 / MW ClO4 = 0.004 mg/kg bw/day x 106.44 / 99.45 = 0.0043 mg/kg bw/day.
- AF for dose response relationship:
- 0.1
- Justification:
- According to EFSA CONTAM Panel, a factor of 10 was applied to account for the lower potency of chlorate compared to perchlorate for the inhibition of iodine uptake in humans (critical effect identified by EFSA).
- AF for differences in duration of exposure:
- 1
- Justification:
- EFSA CONTAM Panel considered the inhibition of thyroid iodine uptake as the critical effect for the chronic hazard characterisation. No further safety factor was considered for duration of exposure.
- AF for interspecies differences (allometric scaling):
- 1
- Justification:
- The study was performed in human volunteers (Greer et al., 2002).
- AF for other interspecies differences:
- 1
- Justification:
- The study was performed in human volunteers (Greer et al., 2002).
- AF for intraspecies differences:
- 1
- Justification:
- The study was performed in human volunteers representing general population. Also, the starting point corresponds to a TDI value, intended to general population (an AF of 4 had already been applied by the EFSA CONTAM Panel to the BMDL value to derive the TDI value for perchlorate).
- AF for the quality of the whole database:
- 1
- Justification:
- The study on inhibition of iodine uptake by perchlorate in human volunteers (Greer et al., 2002) was considered appropriate and was validated by EFSA CONTAM Panel.
- AF for remaining uncertainties:
- 1
- Justification:
- No remaining uncertainties were identified.
Acute/short term exposure
- Hazard assessment conclusion:
- no hazard identified
DNEL related information
General Population - Hazard for the eyes
Local effects
- Hazard assessment conclusion:
- no hazard identified
Additional information - General Population
Risks for public health related to the presence of chlorate in food was assessed by EFSA CONTAM Panel in 2015 1. Inhibition of iodine uptake in humans was identified as the critical effect for chronic exposure to chlorate and perchlorate. A tolerable daily intake (TDI) was set by read-across from a TDI derived for this effect for perchlorate.
The established TDI was based on a BMDL05 for thyroid iodine uptake inhibition by perchlorate from a study performed in human volunteers (Greer et al., 2002), multiplied by a an overall assessment factor of 4.
When comparing the NOAEL and LOAEL for thyroid follicular cell hypertrophy in rats, perchlorate is about 10 times more potent than chlorate. Therefore, the CONTAM Panel established a TDI for chlorate of 3 μg/kg bw/day, based on the TDI established for perchlorate (0.3 μg/kg bw/day) and by multiplying by a factor of 10 for the difference in potency between the two substances.
Then, Weterings et al.2 demonstrated that the physiological intraindividual variation in iodine uptake is much larger than 5%. Therefore, a Benchmark Response (BMR) of 20% was proposed for benchmark dose analysis of human thyroidal iodine uptake data, to take the inherent variation in relative thyroidal uptake of radioactive iodine data into account. The derived TDI from the BMDL20 for perchlorate was then 4 µg/kg bw/day, which is the starting point used to calculate sodium chlorate DNELs.
General population - DNEL oral long-term systemic toxicity
Modified starting point:
The initial study was performed in human volunteers by oral route with perchlorate. The only modification needed is about the difference in molecular weight between perchlorate and sodium chlorate.
TDI (NaClO3) = TDI perchlorate x MW NaClO3 / MW ClO4 = 0.004 mg/kg bw/day x 106.44 / 99.45 = 0.0043 mg/kg bw/day.
Assessment factors:
As applied by the EFSA CONTAM Panel, an assessment factor of 0.1 was used to take into account the 10 times lower potency of chlorate compared to perchlorate towards thyroid function.
The global assessment factor applied to the modified starting point was therefore 0.1.
DNEL oral long-term systemic toxicity = 0.0043 mg/kg bw/day / 0.1 = 0.043 mg/kg bw/day
1 EFSA CONTAM Panel (EFSA Panel on Contaminants in the Food Chain), 2015. Scientific Opinion on risks for public health related to the presence of chlorate in food. EFSA Journal 2015;13(6):4135, 103 pp. doi:10.2903/j.efsa.2015.4135
2 Weterings PJ, Loftus C, Lewandowski TA. Derivation of the critical effect size/benchmark response for the dose-response analysis of the uptake of radioactive iodine in the human thyroid. Toxicol Lett. 2016 Aug 22;257:38-43.
doi: 10.1016/j.toxlet.2016.06.004. PMID: 27268963
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.
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