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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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: 232-019-7 | CAS number: 7783-66-6
- 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
Repeated dose toxicity: oral
Administrative data
- Endpoint:
- repeated dose toxicity: oral
- Remarks:
- combined repeated dose and carcinogenicity
- Type of information:
- migrated information: read-across from supporting substance (structural analogue or surrogate)
- Adequacy of study:
- key study
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: Data published in a peer-reviewed journal, adequate for assessment.
Data source
Reference
- Reference Type:
- publication
- Title:
- Studies on the carcinogenicity of potassium iodide in F344 rats
- Author:
- Takegawa, K et al.
- Year:
- 2 000
- Bibliographic source:
- Food and Chemical Toxicology 38 (2000) 773-781
Materials and methods
Test guideline
- Qualifier:
- no guideline followed
- Principles of method if other than guideline:
- Combined repeated dose and carcinogenicity 2 year study.
- GLP compliance:
- no
- Limit test:
- no
Test material
- Reference substance name:
- Potassium iodide
- EC Number:
- 231-659-4
- EC Name:
- Potassium iodide
- Cas Number:
- 7681-11-0
- IUPAC Name:
- potassium iodide
- Test material form:
- solid: particulate/powder
- Remarks:
- migrated information: powder
- Details on test material:
- - Supplier: Nacalai Tesque (Kyoto, Japan).
- Purity: >99%
Constituent 1
Test animals
- Species:
- rat
- Strain:
- Fischer 344/DuCrj
- Sex:
- male/female
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS
- Source: Charles River Japan (Atsugi, Japan)
- Age at initiation of treatment: 6 weeks
- Housing: Two or three to a polycarbonate cage with wood chips (Softchip, Sankyo Laboratory Service, Tokyo, Japan) for bedding,
- Diet (e.g. ad libitum): CRF-1 diet (Oriental Yeast, Tokyo, Japan), ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 1 week
ENVIRONMENTAL CONDITIONS
- Temperature (°C): 24±1
- Humidity (%): 55±5
- Air changes (per hr): 18
- Photoperiod (hrs dark / hrs light): 12/12
Administration / exposure
- Route of administration:
- oral: drinking water
- Vehicle:
- water
- Analytical verification of doses or concentrations:
- not specified
- Duration of treatment / exposure:
- 2 years
- Frequency of treatment:
- Continuous in drinking water
Doses / concentrations
- Remarks:
- Doses / Concentrations:
10, 100, 1000 ppm
Basis:
nominal in water
- No. of animals per sex per dose:
- 0 and 1000 ppm: 60 animals
10 and 100 ppm: 40 animals - Control animals:
- yes, concurrent vehicle
- Details on study design:
- Both sexes were divided into four groups, each consisting of 60, 40, 40 and 60 rats after the acclimatization, and given KI in the drinking water at concentrations of 0, 10, 100 and 1000 ppm for 2 year, respectively. 1000 ppm was set as the highest dose, exceeding the 260 ppm which has been reported to induce colloid goitres (Kanno J., Onodera H., Furuta K., Maekawa A., Kasuga T. and Hayashi Y. (1992) Tumor-promoting effects of both iodine deficiency and iodine excess in the rat thyroid. Toxicologic Pathology 20, 226-235.). The lowest dose, 10 ppm, was also higher as compared to the optimal one for the rat, namely 0.2 ppm (Kanno et al., 1992).
Examinations
- Observations and examinations performed and frequency:
- During the treatment period, general condition was checked daily, and water consumption was recorded every 2 weeks up to 12 weeks, and every 4 weeks thereafter. Body weights were recorded at the same times.
- Sacrifice and pathology:
- In the 0 and 1000 ppm groups, five rats each were necropsied 3, 6, 12 and 18 months after the initiation of the treatment. All survivors were fasted overnight prior to necropsy, which was performed after exsanguination from the aorta under ether anesthesia. Livers, kidneys, lungs, hearts, spleens, adrenals, brains, pituitaries and thyroids were fixed in 10% neutral buffered formalin, for the interim necropsy. For animals treated for 2 year, in addition to the organs described above, testes, noses, tongues, tracheas, salivary glands, esophagus, stomachs, small and large intestines, pancreas, urinary bladders, prostates, seminal vesicles, ovaries, uteri, vaginae, mammary glands, lymph nodes, sternums, femurs, spinal cords, eye balls, skin and skeletal muscles were fixed in the same manner. Grossly visible lesions were also separately fixed. Histopathological examination was performed on hematoxylin-eosin (HE)-stained specimens processed routinely. Animals that died or were killed in a moribund condition were also necropsied and examined histopathologically. White blood cell count (WBC), red blood cell count (RBC), hemoglobin (Hb), hematocrit (Ht) and platelet count (PLT) were recorded with the aid of an automated hematology analyzer (Sysmex M-2000, Toa Medical Electronics Co., Ltd, Hyogo, Japan).
- Statistics:
- Body weight, water consumption, organ weight and hematology data were analyzed for homogeneity of variance using Bartlett's test. When they proved to be homogeneous, one-way analysis of variance was applied. If significant heterogeneity of variance (P≤0.01) was apparent, the equivalent non-parametric statistical method of Kruskal-Wallis was employed. Where significant differences between the groups were detected, a multiple comparison test (Dunnett's test or Scheffe's method) was used. Final survival rates and the incidences of tumors were compared with the Fisher's exact probability test.
Results and discussion
Results of examinations
- Details on results:
- Survival rates of male rats were decreased in the 100 and 1000 ppm groups as compared to the control from around 80 weeks after the initiation of the treatment. The rates for females of any treated groups were similar to that of the controls. Body weights in the 1000 ppm groups of both sexes were depressed in the latter half of the treatment period. Water consumption in all treated groups was similar to the control level, and KI consumption was accordingly dose dependent. Hematological examination did not reveal any effects of the treatments. On histopathological examination, the incidence of thyroid follicular dilatation was found to be increased in the 10, 100 and 1000 ppm groups of both sexes (the incidence did not decrease with decreasing dose levels). This change is however not neoplastic. This lesion was composed of increased colloid in the lumen and flattened epithelia due to the compression. Thyroid proliferative lesions derived from follicular epithelia were not increased by KI treatment, although examples were observed in each group. It was therefore concluded that long-term treatment of KI per se does not result in thyroid tumor induction in rats. In the salivary gland, focal acinar atrophy, ductular proliferation and squamous metaplasias were frequently observed, and squamous cell carcinomas were noted in four males and three females of the 1000 ppm group. SCCs of the submandibular gland were unlikely to affect the survival rate, since the incidence was low. Lobular atrophies were well-circumscribed from the surrounding tissue and triangular in shape, suggesting focal lesions related to single ducts, and accompanied by ductular proliferation in most cases. Squamous metaplasias were observed in the epithelium of proliferating ductules, and the morphological continuum to squamous cell carcinomas were observed in these metaplasias. No KI-related induction of any lesions was apparent in the other organs or tissues. Lesions with incidences more than 25% in one or more groups were, foci of cellular alteration in the liver and hyperplasias of the pituitary in both sexes, C-cell hyperplasias of the thyroid, medullary hyperplasias and pheochromocytomas of the adrenals, and interstitial cell tumors of the testis in males, and cystic endometrial hyperplasias and endometrial stromal polyps of the uterus in females. However, these are all known to spontaneously occur and neither increase in their incidence nor special types of lesions were observed in the treated groups. With regard to animals necropsied 3, 6, 12 and 18 months after the initiation of the treatment, the numbers with follicular dilatation in the thyroid were apparently increased in the 1000 ppm group as compared to the controls from 3 months. No treatment-related effects were evident in other organs.
The cause of decreased survival at the end of the treatment period in males of the 100 ppm and 1000 ppm groups in the long-term carcinogenicity study was not considered to be directly related to compression of the respiratory tract due to thyroid enlargement, since follicular dilatation of the thyroid did not show such a marked thyroidal enlargement. Overall, no possible causes for the depressed survival rates were clear. Furthermore, KI does not appear to have systemic toxic effects, other than the effect on the thyroid, at concentrations of 10 and 100 ppm, since body weight gain was not inhibited at this level of exposure.
Effect levels
- Dose descriptor:
- LOAEL
- Effect level:
- 0.55 mg/kg bw/day (nominal)
- Based on:
- test mat.
- Sex:
- male/female
- Basis for effect level:
- other: Thyroid findings
Target system / organ toxicity
- Critical effects observed:
- not specified
Applicant's summary and conclusion
- Conclusions:
- A LOAEL of 0.55 mg/kg bw/day was determined in a 2-year drinking water study with potassium iodide in rats.
- Executive summary:
In a chronic toxicity study male and female F344/DuCrj rats received potassium iodide (KI) in the drinking water at concentrations of 0, 10, 100 or 1000 ppm for 2 years. The average daily intakes (males - females) were 0, 0.55 - 0.66, 5.31 - 6.73. and 53.03 - 66.59 mg/kg bw/day. Survival rates of male rats were decreased in the100 and 1000 ppm groups. Body weights in the 1000 ppm groups of both sexes were decreased in the latter half of the treatment period. The incidence of thyroid follicular dilatation was increased in the 10, 100 and 1000 ppm groups of both sexes (the incidence of this non-neoplastic lesion did not decrease with decreasing dose levels). In the submandibular salivary gland of male adn female rats of the 1000 ppm group squamous cell carcinomas were observed, along with focal acinar atrophy and/or ductular proliferation, frequently accompanied by squamous metaplasia. No KI-related induction of any lesions was apparent in any other organ or tissue. The lowest dose level of 0.55 mg/kg bw/day was considered to be a LOAEL based on the non-neoplastic thyroid change.
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.