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EC number: 231-164-3 | CAS number: 7440-56-4
- 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
Endpoint summary
Administrative data
Link to relevant study record(s)
- Endpoint:
- basic toxicokinetics in vitro / ex vivo
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- test procedure in accordance with generally accepted scientific standards and described in sufficient detail
- Remarks:
- Test according to state-of-the-art operating procedures for testing of metal bioelution.
- Objective of study:
- bioaccessibility (or bioavailability)
- Qualifier:
- according to guideline
- Guideline:
- other: ASTM D5517-07: Standard Test Method for determining the extractability of metals from art materials - ASTM, 2007 (American Society for Testing and Materials).
- Principles of method if other than guideline:
- The release/dissolution of germanium from germanium metal powder in simulated gastric fluid was measured. The resulting value is termed bio-accessibility, and is defined as the fraction of a substance that is soluble under physiological conditions and therefore potentially available for absorption into systemic circulation. The simulated gastric fluid represents an exposure-relevant exposure route (oral exposure). The compound was introduced as powder in a test item / solution ratio of 200 mg/L during 2 hours.
- GLP compliance:
- yes
- Specific details on test material used for the study:
- batch used = Zwarte C-mal 229-1 (= filtered Zwarte C-mal 229-2, to obtain particles below 100 µm)
- Preliminary studies:
- not applicable
- Type:
- other: bioaccessibility
- Results:
- gastric fluid (0hours): as %Ge released of total Ge content: 0.13
- Type:
- other: bioaccessibility
- Results:
- gastric fluid (1hours): as %Ge released of total Ge content: 4.27
- Type:
- other: bioaccessibility
- Results:
- gastric fluid (2hours): as %Ge released of total Ge content: 5.83
- Details on absorption:
- not applicable
- Details on distribution in tissues:
- not applicable
- Details on excretion:
- not applicable
- Metabolites identified:
- not measured
- Details on metabolites:
- not applicalbe
- Bioaccessibility (or Bioavailability) testing results:
- gastric fluid (0hours): as %Ge released of total Ge content: 0.13
gastric fluid (1hours): as %Ge released of total Ge content: 4.27
gastric fluid (2hours): as %Ge released of total Ge content: 5.83 - Conclusions:
- The dissolution in gastric fluid is used to estimate bioavailability after oral exposure. Bio-elution test according to state-of-the-art procedures, useful for determining dissolution capacity of In in gastric fluid.
Interpretation of results: low bioaccessibility of Ge from germanium - Executive summary:
During this study on Germanium at a loading of 0.2 g/L in simulated gastric fluid (pH 1.2), it was shown that a significant amount of germanium (average dissolved germanium concentration of 11.3 ± 0.4 mg/L
Ge or 56.6 mg/g Ge with a between-vessel variation of 3% (CV=3%)) was measured after 2 hours of extraction. Based on the specific surface area of germanium (i.e. 1.19 m²/g test item ) a germanium release per surface of 47.6 mg/m² was calculated. Based on the germanium content in the test item ( 97.2%) and the average dissolved germanium concentration, a germanium release of 5.83% could be calculated
- Endpoint:
- basic toxicokinetics in vivo
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- study well documented, meets generally accepted scientific principles, acceptable for assessment
- Justification for type of information:
- see section 13 in IUCLID for read-across justification report
- Objective of study:
- absorption
- distribution
- toxicokinetics
- Qualifier:
- no guideline followed
- Principles of method if other than guideline:
- Absorption, transport, distribution, storage and excretion of inorganic germanium in albino rats.
GeO2: Gastrointestinal absorption and transport and elimination of GeO2 by the blood after oral administration - GLP compliance:
- not specified
- Radiolabelling:
- no
- Species:
- rat
- Strain:
- other: albino
- Sex:
- male/female
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS
- Source: no information
- Age at study initiation: no information
- Weight at study initiation: no information
- Fasting period before study: 36hrs
- Housing: well ventilated cages
- Individual metabolism cages: no information
- Diet (e.g. ad libitum): no information
- Water (e.g. ad libitum): no information
- Acclimation period: 1 week
ENVIRONMENTAL CONDITIONS : no information
- Temperature (°C):
- Humidity (%):
- Air changes (per hr):
- Photoperiod (hrs dark / hrs light): - Route of administration:
- oral: gavage
- Vehicle:
- water
- Duration and frequency of treatment / exposure:
- single dose
- Dose / conc.:
- 50 mg/kg bw/day (actual dose received)
- Remarks:
- rats of 200g are fed 10 mg GeO2 by stomach tube
- Control animals:
- not specified
- Type:
- absorption
- Results:
- rapid absorption after gavage (73.6% after 4h and 96.4% after 8h)
- Type:
- distribution
- Results:
- uniformly distributed between erythrocytes and plasma (2:3) and not bound to plasma proteins. Not deposited selectively but widely distributed among all the organs.
- Metabolites identified:
- not measured
- Details on metabolites:
- not applicable
- Conclusions:
Germanium is relatively inert metabolically and are consonant with its remarkably low toxicity
Interpretation of results : low bioaccumulation potential based on study results- Executive summary:
Metabolic studies have been conducted of the absorption, transport, distribution, storage and excretion of inorganic germanium (GeO2 and sodium germanate) in albino rats.
The analytical data demonstrate that germanium is rapidly absorbed after oral, subcutaneous, intramuscular or intraperitoneal administration.
When injected directly into the systemic circulation or absorbed following oral or parenteral administration, it is transported unbound by plasma proteins and is rapidly eliminated from the blood stream.
Germanium (sodium germanate) is not deposited selectively but is widely distributed among all the organs. It is not retained or stored by any tissue even after many weekly doses, but is rapidly excreted via the urine and feces, the kidney bein the main excretory organ.
- Endpoint:
- basic toxicokinetics in vivo
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- study well documented, meets generally accepted scientific principles, acceptable for assessment
- Justification for type of information:
- see section 13 in IUCLID for read-across justification report
- Objective of study:
- distribution
- toxicokinetics
- Qualifier:
- no guideline followed
- Principles of method if other than guideline:
- - Principle of test: investigation of the kinetics of germanium dioxide (GeO2) after single dose exposure; investigation of tissue distribution in a repeated exposure study (4wk)
- GLP compliance:
- not specified
- Specific details on test material used for the study:
- SOURCE OF TEST MATERIAL
Germanium dioxide [germanium (IV) oxide, 99.999% pure, Showa Chemicals, Tokyo, Japan] - Radiolabelling:
- no
- Species:
- rat
- Strain:
- Wistar
- Sex:
- male
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS
- Source: no information
- Age at study initiation: no information
- Weight at study initiation: 300-350 gr
- Housing: in non-restrained cages
- Diet: normal diet containing no germanium free of access
- Water: fresh water containing no germanium free of access
- Acclimation period: no information
ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22
- Humidity (%): no information
- Air changes (per hr): no information
- Photoperiod (hrs dark / hrs light): 12/12
- Route of administration:
- oral: gavage
- Vehicle:
- other: double-distilled water
- Details on exposure:
- PREPARATION OF DOSING SOLUTIONS:
GeO2 was dissolved in double-distilled water - Duration and frequency of treatment / exposure:
- singe dose exposure and repeated dose exposure study for 4 weeks
- Dose / conc.:
- 100 mg/kg bw/day
- Remarks:
- in a single dose exposure study and in a 4 weeks repeated dose exposure study
- No. of animals per sex per dose / concentration:
- total of 36 rats used in the whole study: 6 rats assigned to the single dose exposure study and 30 rats for the repeated dose exposure study (15 exposed and 15 controls)
- Control animals:
- yes, concurrent vehicle
- Positive control reference chemical:
- no
- Details on study design:
- - Dose selection rationale: Based on data of published data Matsumuro et al 1993 showing germanium neuropathy could be induced in rats by supplying 100mg/kg BW GeO2, 100 mg/kg BW was selected to study the kinetics of GeO2
- Details on dosing and sampling:
- TOXICOKINETIC / PHARMACOKINETIC STUDY (Absorption, distribution, excretion)
- Tissues and body fluids sampled : blood, tissues: brain cortex, lung, heart, liver, kidney, sciatic nerve, and gastrocnemius muscle
- Time and frequency of sampling:
single dose exposure group study: Blood samples of 1 ml were collected from rat’s tail artery, respectively before feeding and at 0.25, 0.5, 1, 2, 4, 8, 12, and 24 h after GeO2 administration
repeated exposure group and control group study: Blood samples of 1 ml were also collected from rat’s tail artery under ether anesthesia, both at the moments of pre-exposure and just before sacrifice 4 weeks later. - Statistics:
- The statistical analysis of results was performed with student’s t-test.
- Type:
- distribution
- Results:
- GeO2 accumulated especially in the peripheral nerves and kidneys
- Test no.:
- #1
- Toxicokinetic parameters:
- Cmax: 15.5 µg/ml
- Remarks:
- mean maximum concentration in serum
- Test no.:
- #1
- Toxicokinetic parameters:
- half-life 1st: 2.3 hours
- Remarks:
- mean elimination half-time
- Test no.:
- #1
- Toxicokinetic parameters:
- half-life 1st: 0.7 hours
- Remarks:
- mean absorption half time
- Metabolites identified:
- not measured
- Conclusions:
- Lin et al (1999) reported the kinetics of GeO2 in male Wistar rats after the oral administration of a single dose (100mg/kg) and found that maximal mean serum concentration was achieved in 0.7 hour and the mean elimination half-time was 2.3 hours. Lin et al, also conducted a multiple dose for 4 weeks and found highest concentrations of Ge in peripheral nerves and kidneys.
- Executive summary:
The kinetics of germanium dioxide (GeO2) in single dose and repeated exposures were investigated in male Wistar rats. In the single dose GeO2 (100 mg:kg BW, p.o.) exposure study, values of several kinetic parameters were shown as follows, a maximum concentration in serum of 15.5 +/- 0.7 µg:/ml (mean +/-S.E.M.), an absorption half-life of 0.7 +/- 0.1 h (mean +/- S.E.M.), an elimination half-life of 2.3 +/-0.5 h (mean+/-S.E.M.), a distribution of the central compartment Vp (3.1 +/- 0.3 l, mean +/- S.E.M.), and the apparent volume of distribution of the tissue compartment Vt (8.5 +/- 2.9 l, mean +/-S.E.M.). In the repeated exposure study, 730 +/- 92 mg GeO2 in 1 l double-distilled H2O (100 mg:kg:day) was given daily to rats for 4 weeks (p.o.). After sacrificing the rats, the analysis of tissue distribution showed that GeO2 was accumulated in some important organs or tissues in the body, especially the peripheral nerves and kidney. These results indicate that GeO2 could be absorbed rapidly but had a longer elimination half-life in rats. In addition, GeO2 was accumulated especially in the nerves and kidney following long-term exposure.
- Endpoint:
- dermal absorption in vivo
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- study well documented, meets generally accepted scientific principles, acceptable for assessment
- Justification for type of information:
- see section 13 in IUCLID for read-across justification report
- Qualifier:
- no guideline followed
- Principles of method if other than guideline:
- - Principle of test: Three groups of rats were treated with a 3-h topical application of hydrophilic ointment containing graded level of neutralized GeO2 (pH 7.4): 0,
0.21 and 0.42 mg GeO2/g. Germanium concentration in blood and tissues sampled from rats after topical application of inorganic germanium was measured by inductively coupled plasma-mass spectrometry - GLP compliance:
- yes
- Species:
- rat
- Strain:
- Fischer 344
- Sex:
- male
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS
- Source: Japan SLC Inc., Shizuoka, Japan.
- Age at study initiation: 4-week-old
- Weight at study initiation: 50–70 g (mean 56.8 g, standard deviation 3.5 g
- Fasting period before study: no
- Housing: kept individually in stainless steel cages with raised wire bottoms
- Individual metabolism cages: yes
- Diet: free access to AIN-93G diet
- Water: free access to deionized water
- Acclimation period: 2 weeks
ENVIRONMENTAL CONDITIONS: no information
- Type of coverage:
- not specified
- Vehicle:
- other:
- Duration of exposure:
- 3h
- Doses:
- 0, 0.21 mg/g and 0.42 mg/g
- No. of animals per group:
- 6
- Control animals:
- yes
- Details on study design:
- DOSE PREPARATION
- Method for preparation of dose suspensions:
Preparation of inorganic germanium ointment:
Hydrophilic ointment containing neutralized GeO2 (inorganic germanium ointment) was prepared as follows. GeO2 of 2.5 g was stirred with excess amount of sodium hydroxide in deionized water (MilliQ, Millipore Co.) for hydrolysis. The alkaline solution
containing hydrolyzed GeO2 was neutralized with hydrochloric acid to give a solution with pH 7.4. Purified water was added to obtain 2.5 g/L neutralized GeO2 solution (1.735 g of elemental germanium/L). To prepare inorganic germanium ointment containing 0.42 mg GeO2/g, 3 mL of 2.5 g/L neutralized GeO2 solution was added to 15 g of hydrophilic ointment (Yoshida Pharmaceutical Co., Saitama, Japan) concordant to Japan Pharmacopoeia that contains 250 g white petrolatum, 200 g stearylalcohol, 120 g propyleneglycol, 40 g polyoxyethylene (60) hydrogenated castor oil, 10 g monostearylglycerine, 1 g methyl p-hydroxybenzoate, 1 g propyl p-hydroxybenzoate, and 378 g purified water per 1000 g. They were thoroughly mixed with a Teflon-coated ointment spatula on a 30 cm x 30 cm square polyvinyl chloride board. Similarly, 1.5 mL of 2.5 g/L neutralized GeO2 solution, 1.5 mL purified water, and 15 g hydrophilic ointment was mixed to obtain inorganic germanium ointment containing 0.21 mg GeO2/g.
APPLICATION OF DOSE: topical; Polyvinylidene chloride food wrap (Saran Wrap, Asahi Kasei Home Products Co., Tokyo, Japan) was cut into 2 cm x 2 cm square sheets and attached on cotton gauze by adhesives (Alonalpha, Toa Gosei Chemical Industry, Tokyo, Japan). 2 g of inorganic germanium ointment or blank ointment were spread on the polyvinylidene chloride sheet attached on cotton gauze for applying to the hair-removed skin.
VEHICLE
negative control: 3 mL purified water was mixed with 15 g hydrophilic ointment to prepare blank ointment.
TEST SITE:
A patch of hair approximately 3 x 4 cm from the dorsal abdominal surface along the spinal axis was clipped with an animal hair clipper. The remaining hair was removed with a depilatory cream (Epilat, Kanebo, Tokyo, Japan). The animals were
washed by warm tap water, and their fur was wiped by a towel and dried by a hair dryer. After overnight withdrawal of diets, the hydrophilic ointment containing neutralized GeO2 (inorganic germanium ointment) spread on the polyvinylidene chloride
sheet attached on cotton gauze was applied to the rat skin re-covered with short hair (approximately 1 mm length) after hair removal.
ANALYSIS
- Method type(s) for identification : Germanium concentration in the sample solution was measured by inductively coupled argon plasma-mass spectrometry (ICPM-8500, Shimadzu, Co., Kyoto, Japan).
- Signs and symptoms of toxicity:
- not examined
- Dermal irritation:
- not examined
- Time point:
- 3 h
- Dose:
- 0.21 mg/g
- Parameter:
- amount
- Remarks:
- in plasma
- Absorption:
- ca. 5.5 other: ng/g
- Remarks on result:
- other: average value in plasma based on reported graphs
- Time point:
- 3 h
- Dose:
- 0.21 mg/g
- Parameter:
- amount
- Remarks:
- in liver
- Absorption:
- ca. 6.4 other: ng/g
- Remarks on result:
- other: average value in liver based on reported graphs
- Time point:
- 3 h
- Dose:
- 0.21 mg/g
- Parameter:
- amount
- Remarks:
- in blood
- Absorption:
- ca. 3.8 other: ng/g
- Remarks on result:
- other: average value in blood based on reported graphs
- Time point:
- 3 h
- Dose:
- 0.21 mg/g
- Parameter:
- amount
- Remarks:
- in kidney
- Absorption:
- ca. 18 other: ng/g
- Remarks on result:
- other: average value in kidney based on reported graphs
- Time point:
- 3 h
- Dose:
- 0.42 mg/g
- Parameter:
- amount
- Remarks:
- in plasma
- Absorption:
- ca. 8.8 other: ng/g
- Remarks on result:
- other: average value in plasma based on reported graphs
- Time point:
- 3 h
- Dose:
- 0.42 mg/g
- Parameter:
- amount
- Remarks:
- in liver
- Absorption:
- ca. 15 other: ng/g
- Remarks on result:
- other: average value in liver based on reported graphs
- Time point:
- 3 h
- Dose:
- 0.42 mg/g
- Parameter:
- amount
- Remarks:
- in blood
- Absorption:
- ca. 5.3 other: ng/g
- Remarks on result:
- other: average value in blood based on reported graphs
- Time point:
- 3 h
- Dose:
- 0.42 mg/g
- Parameter:
- amount
- Remarks:
- in kidney
- Absorption:
- ca. 37 other: ng/g
- Remarks on result:
- other: average value in kidney based on reported graphs
- Conclusions:
- After 3-hour dermal exposure (depilated dorsal skin) of male F344 / N rats to a neutralized solution of sodium germanate (GeO2 dissolved in NaOH) in a hydrophilic ointment base (2 g ointment containing 0, 0.21 or 0.42 mg GeO2 / g ), the germanium content in whole blood, plasma, liver and kidney increased in a dose-dependent manner. The kidney content was about three times higher than that in the liver
- Executive summary:
In this study the dermal absorption of neutralized GeO2 or germanate using male F344/N rats was investigated. Three groups of rats were treated with a 3-h topical application of hydrophilic ointment containing graded level of neutralized GeO2 (pH 7.4): 0, 0.21 and 0.42 mg GeO2/g. Germanium concentration in blood and tissues sampled from rats after topical application of inorganic germanium was measured by inductively coupled plasma-mass spectrometry. Animals topically applied 0.42 mg GeO2/g ointment had significantly higher germanium concentrations in plasma, liver, and kidney than those of rats that received no topical germanium. The results indicate that skin is permeable to inorganic germanium ion or germanate and recurrent exposure of germanium compounds may pose a potential health hazard.
Referenceopen allclose all
Germanium, loading 0.2 g/L (= 1.19 m²/L surface loading) |
|||
|
|
2-h gastric at pH 1.2 |
|
Analyte |
|
xavg± sbetween |
CV |
germanium (Ge) |
dissolution |
11.3 ±0.4 mg/L |
3% |
|
absolute Ge release |
56.6 ± 2.0 mg/g |
3% |
|
% of total availableGeeluted |
5.83% |
|
|
Ge release/surface |
47.6 mg/m² |
xavg= average of 3 test vessels (blank corrected, if the blank value is > reporting limit, otherwise blank assumed as 0).
sbetween= standard deviation.
CV = Coefficient of Variation (%).
Description of key information
In vitro studies have evaluated the dissolution rates of germanium metal. Data on the bioaccessibility of germanium metal in biological fluid (gastric medium pH 1.5) as a surrogate for bioavailability are reported within section 7.1.1 of IUCLID (Brouwers et al, ECTX, 2015). Gastric medium mimics the release of Ge from Ge metal after oral exposure.
For Germanium and its compounds, systemic toxicity is attributed to the germanium ion and differences in toxicity are principally linked to bioavailability. The bioelution data (for details see IUCLID section 7.1.1) are summarized below and have been incorporated into read-across assessments for Ge and Ge compounds. Further details related to the specific endpoints for which read-across approach was used, is summarized in section 13 of IUCLID (read across justification report).
Table- Bio-elution data on germanium and germanium compounds (germanium dioxide) measured in gastric fluids
Test Substance |
Bioaccessibility in Gastric fluid (2 hours, loading 0.2g/L) as (% In released of total In-content) |
Reference |
GeO2 |
23.3 |
Brouwers T, 2015 |
Ge |
5.83 |
Brouwers T, 2015 |
Animal studies:
Absorption, Distribution, Excretion:
Oral:
The study of Rosenfeld (1954) on rats after gavage to GeO2, demonstrates that germanium is rapidly absorbed after oral administration (73.6% in 4 hours; 96.4% in 8 hours).
When absorbed following oral administration, germanium is transported unbound by plasma proteins and is rapidly eliminated from the blood stream.
The biological half-life of germanium is relatively short, on the order of 1 -2 days in the liver and whole body and 4.5 days in the kidneys of rats (Rosenfeld, 1954).
Lin et al (1999) reported the kinetics of GeO2 in male Wistar rats after the oral administration of a single dose (100mg/kg) and found that maximal mean serum concentration was achieved in 0.7 hour and the mean elimination half-time was 2.3 hours. Lin et al, also conducted a multiple dose for 4 weeks and found highest concentrations of Ge in peripheral nerves and kidneys.
Inhalation:
The rate of clearance of deposited elemental germanium particles (mean size 1.7 µm) from the lungs of rats was found to be exponential (52% in 24 hours, 82% at 7th day after exposure). Radiochemical examination of the tissues showed that part of the material entered the circulation and reappeared in the kidney and liver 1 hour after exposure. The clearance of germanium dioxide particles (mean size 0.4 µm) was more rapid than that of elemental Ge particles (79% within 24 hours and nearly 100% at 4th day) (Dudley, 1953)
Dermal:
After 3-hour dermal exposure (depilated dorsal skin) of male F344/N rats to a neutralized solution of sodium germanate (GeO2 dissolved in NaOH) in a hydrophilic ointment base (2g ointment containing 0, 0.21 or 0.42 mg GeO2/g) the germanium content in whole blood, plasma, liver and kidney increased in a dose-dependent manner. The Ge content in the kidney was about three times higher than that in the liver (Yokoi et al, 2008). The results indicate that skin is permeable to inorganic germanium ion or germanate.
Human information:
Inhalation:
Roels and Buchet (2001) collected urine samples at the beginning and at the end of the day shift from workers occupationally exposed to Ge or GeO2 by inhalation. The urinary elimination rate of germanium was studied in seven workers, and the urinary elimination rates (half-times) ranged from 8.2 -18.1 hours. The study did not allow discrimination between the germanium species to which the workers were exposed but it showed fast urinary urinary elimination kinetics for inhalation exposure to dust of metallic Ge and GeO2.
References (in extra to study records):
- Dudley HC 1953: Pharmacological studies of radiogermanium (Ge71). II. Inhalation of dusts, AMA Arch Ind Hyg Occup Med. 8(6): 528 -530
Key value for chemical safety assessment
- Bioaccumulation potential:
- low bioaccumulation potential
- Absorption rate - oral (%):
- 73.6
Additional information
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