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EC number: 215-231-4 | CAS number: 1314-35-8
- 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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Toxicity to birds
Administrative data
Link to relevant study record(s)
- Endpoint:
- toxicity to birds, other
- Remarks:
- egg production and hatchability
- Type of information:
- read-across based on grouping of substances (category approach)
- Adequacy of study:
- weight of evidence
- Reliability:
- 4 (not assignable)
- Rationale for reliability incl. deficiencies:
- documentation insufficient for assessment
- Remarks:
- Not enough information to assess the quality of the study. Lacking detail on husbandry, housing, dosing accuracy, and statistical analysis. Due to similar or lower transformation/dissolution results for tungsten trioxide (the target substance) than sodium tungstate (the source substance), the resulting toxicity potential would also be expected to be similar or lower, so read-across is appropriate. In addition, read-across is justified because the classification and labelling is the same or less severe for the target substance PBT/vPvB profile is the same. Finally, the dose descriptors are, or are expected to be, sufficiently similar or higher for the target substance, and read-across to the source chemical is adequately protective. For more details refer to the attached description of the read across approach on Annex 3 in the CSR.
- Justification for type of information:
- 1. HYPOTHESIS FOR THE CATEGORY APPROACH: The hypothesis is that properties are likely to be similar or follow a similar pattern because of the presence of a common metal ion, in this case tungstate.
2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES):
Source: Sodium tungstate
Target: Tungsten trioxide
3. CATEGORY APPROACH JUSTIFICATION: See Annex 3 in CSR
4. DATA MATRIX: See Annex 3 in CSR - Reason / purpose for cross-reference:
- read-across: supporting information
- Qualifier:
- no guideline followed
- Principles of method if other than guideline:
- Hens were fed the test substance, and xanthine dehydrogenase levels were monitored in the tissues. Chicks from eggs laid by these birds were then used in growth tests where they were fed additional test substance or not. These chicks were compared to chicks whose hens had not been fed the test substance. Xanthine dehydrogenase levels were monitored in the tissues of the chicks as well.
- GLP compliance:
- no
- Dose method:
- feed
- Analytical monitoring:
- no
- Vehicle:
- not specified
- Details on preparation and analysis of diet:
- Breeder ration supplement with 250 ppm tungsten, as sodium tungstate.
- Test organisms (species):
- other: Breeder hens, (WPC)
- Details on test organisms:
- TEST ORGANISM
- Common name: Breeder hens
- Sexes used: Females, with adequate males to ensure maximum fertility - Limit test:
- no
- Total exposure duration (if not single dose):
- 4 wk
- Remarks:
- Hens fed tungsten for 30 days prior to setting and hatching eggs.
- Post exposure observation period:
- None
- No. of animals per sex per dose and/or stage:
- Experiment 1- Controls-65 hens, Treated-95 hens
Experiment 2, Trial 1- 40 chicks treated, (20 from treated hens, 20 from control); 40 chicks not treated (20 from treated hens, 20 from control)
Experiment 2, Trial 2- 52 chicks treated (26 from treated hens, 26 from control) 40 chicks not treated (26 from treated hens, 26 from control) - Control animals:
- yes, plain diet
- Nominal and measured doses / concentrations:
- Experiment 1-Hens-First 10 days, 250 ppm test substance, the next 20 days, 500 ppm test substance.
Experiment 2, Trial 1 -Chicks, 500 ppm test substance, 4 weeks (breeder ration)
Experiment 2, Trial 2-Chicks, 500 ppm test substance, 24 days (broiler ration) - Details on test conditions:
- -No information on adult hen conditions.
-Chicks were reared in starter-type battery brooders equipped with wire screen floors.
-Chicks were fed food and water ad libitum.
-Weekly chick weights and individual gain and feed conversion data were collected. - Details on examinations and observations:
- n/a
- Details on reproductive parameters:
- n/a
- Reference substance (positive control):
- no
- Duration (if not single dose):
- 30 d
- Dose descriptor:
- LOEC
- Effect level:
- 500 mg/kg diet
- Conc. / dose based on:
- test mat.
- Basis for effect:
- other: decline in xanthine dehydrogenase activity
- Remarks on result:
- other: Experiment 1
- Duration (if not single dose):
- 10 d
- Dose descriptor:
- NOEC
- Effect level:
- 250 mg/kg diet
- Conc. / dose based on:
- test mat.
- Basis for effect:
- other: decline in xanthine dehydrogenase activity
- Remarks on result:
- other: Experiement 1
- Duration (if not single dose):
- 30 d
- Dose descriptor:
- NOEC
- Effect level:
- 500 mg/kg diet
- Conc. / dose based on:
- test mat.
- Basis for effect:
- other: egg production and hatchability
- Remarks on result:
- other: experiment 1
- Duration (if not single dose):
- 4 wk
- Dose descriptor:
- LOEC
- Effect level:
- 500 mg/kg diet
- Conc. / dose based on:
- test mat.
- Basis for effect:
- other: feed conversion and growth depression
- Remarks on result:
- other: Experiment 2; only one concentration tested
- Mortality and sub-lethal effects:
- No mortality was reported
- Reported statistics and error estimates:
- Analysis of variance was used to compare results within the same experiment.
- Conclusions:
- Chicks from hens fed a sodium tungstate supplemented ration grew at a significantly slower rate than controls. Chicks fed sodium tungstate grew at a slower rate than chicks who were not fed the test substance. 500 ppm test substance did not apear to effect egg production or hatchability.
- Executive summary:
No toxicity to birds data of sufficient quality are available for tungsten trioxide (target substance). However, toxicity to birds data are available for sodium tungstate (source substance), whichareused for read-across. Due to lower water solubility and lower toxicity for the target substance compared to the source substance, the resulting read-across from the source substance to the target substance is appropriate as a conservative estimate of potential toxicity for this endpoint. In addition, read-across is appropriate because the classification and labelling is more protective for the source substance than the target substance, the PBT/vPvB profile is the same, and the dose descriptors are, or are expected to be, lower for the source substance. For more details, refer to the read-across category approach description in the Category section of this IUCLID submission or Annex 3 of the CSR.
- Endpoint:
- short-term toxicity to birds: dietary toxicity test
- Type of information:
- read-across based on grouping of substances (category approach)
- Adequacy of study:
- weight of evidence
- Study period:
- N/A
- Reliability:
- 4 (not assignable)
- Rationale for reliability incl. deficiencies:
- documentation insufficient for assessment
- Remarks:
- Non-standard study with insufficient information provided on methods to adequately evaluate data. Due to similar or lower transformation/dissolution results for tungsten trioxide (the target substance) than sodium tungstate (the source substance), the resulting toxicity potential would also be expected to be similar or lower, so read-across is appropriate. In addition, read-across is justified because the classification and labelling is the same or less severe for the target substance PBT/vPvB profile is the same. Finally, the dose descriptors are, or are expected to be, sufficiently similar or higher for the target substance, and read-across to the source chemical is adequately protective. For more details refer to the attached description of the read across approach on Annex 3 in the CSR.
- Justification for type of information:
- 1. HYPOTHESIS FOR THE CATEGORY APPROACH: The hypothesis is that properties are likely to be similar or follow a similar pattern because of the presence of a common metal ion, in this case tungstate.
2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES):
Source: Sodium tungstate
Target: Tungsten trioxide
3. CATEGORY APPROACH JUSTIFICATION: See Annex 3 in CSR
4. DATA MATRIX: See Annex 3 in CSR - Reason / purpose for cross-reference:
- read-across: supporting information
- Qualifier:
- no guideline available
- Principles of method if other than guideline:
- Chicks were fed varying amount of tungsten as sodium tungstate in the diet. Growth effects and xanthine dehydrogenase activity were monitored over 6 weeks.
- GLP compliance:
- no
- Dose method:
- feed
- Analytical monitoring:
- no
- Vehicle:
- no
- Details on preparation and analysis of diet:
- DIET PREPARATION
- Description and nutrient analysis of basal diet provided in study report: yes
- Preparation of doses: No details - Test organisms (species):
- other: White Leghorn Chicks (Genus and Species not provided)
- Details on test organisms:
- TEST ORGANISM
- Common name: White Leghorns
- Age at test initiation (mean and range, SD): 1 day old
- Weight at test initiation (mean and range, SD): 40-44 g average
- Sexes used: mixed - Limit test:
- no
- Total exposure duration (if not single dose):
- 6 wk
- Post exposure observation period:
- None
- No. of animals per sex per dose and/or stage:
- 9 groups total, 29 chicks each in groups 4 and 8; 22 chicks each in all other groups. Group 1 is the control. See Table 1, below
- Control animals:
- yes, plain diet
- Nominal and measured doses / concentrations:
- Groups 1, 2- no tungsten. Group 1 starter mash diet
Groups 4- 45mg/kg tungsten.
Groups 8 - 94 mg/kg tungsten; See Table 1, below. - Details on test conditions:
- NO. OF BIRDS PER REPLICATE
- For negative control: 22 or 29
- For treated: 22 or 29
NO. OF REPLICATES PER GROUP
- For negative control: 1
- For treated: 1
- Details on examinations and observations:
- N/A
- Details on reproductive parameters:
- N/A
- Reference substance (positive control):
- no
- Duration (if not single dose):
- 5 wk
- Dose descriptor:
- LOEC
- Effect level:
- 45 mg/kg diet
- Conc. / dose based on:
- other: mg tungsten
- Basis for effect:
- other: decrease in xanthine dehydrogenase and molybdenum concentrations; body weight
- Remarks on result:
- other: lowest concentration tested
- Repellency factors (if applicable):
- N/A
- Mortality and sub-lethal effects:
- Mortality- 3 weeks
Group 4-14%
Group 8-24%
Mortality- 5 weeks
Group 4-24%
Group 8-28% - Effects on reproduction:
- N/A
- Results with reference substance (positive control):
- N/A
- Further details on results:
- See below
- Conclusions:
- Molybdenum deficiency in chicks can be induced by the addition of tungsten to the diet. At high levels, this can reduce growth rate, and markedly depletes tissue xanthine dehydrogenase and molybdenum levels.
- Executive summary:
No toxicity to birds data of sufficient quality are available for tungsten trioxide (target substance). However, toxicity to birds data are available for sodium tungstate (source substance), whichareused for read-across. Due to lower water solubility and lower toxicity for the target substance compared to the source substance, the resulting read-across from the source substance to the target substance is appropriate as a conservative estimate of potential toxicity for this endpoint. In addition, read-across is appropriate because the classification and labelling is more protective for the source substance than the target substance, the PBT/vPvB profile is the same, and the dose descriptors are, or are expected to be, lower for the source substance. For more details, refer to the read-across category approach description in the Category section of this IUCLID submission or Annex 3 of the CSR.
- Endpoint:
- short-term toxicity to birds: dietary toxicity test
- Type of information:
- read-across based on grouping of substances (category approach)
- Adequacy of study:
- weight of evidence
- Reliability:
- 4 (not assignable)
- Rationale for reliability incl. deficiencies:
- documentation insufficient for assessment
- Remarks:
- Insufficient information provided on methods to accurately evaluate the study. Due to similar or lower transformation/dissolution results for tungsten trioxide (the target substance) than sodium tungstate (the source substance), the resulting toxicity potential would also be expected to be similar or lower, so read-across is appropriate. In addition, read-across is justified because the classification and labelling is the same or less severe for the target substance PBT/vPvB profile is the same. Finally, the dose descriptors are, or are expected to be, sufficiently similar or higher for the target substance, and read-across to the source chemical is adequately protective. For more details refer to the attached description of the read across approach on Annex 3 in the CSR.
- Justification for type of information:
- 1. HYPOTHESIS FOR THE CATEGORY APPROACH: The hypothesis is that properties are likely to be similar or follow a similar pattern because of the presence of a common metal ion, in this case tungstate.
2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES):
Source: Sodium tungstate
Target: Tungsten trioxide
3. CATEGORY APPROACH JUSTIFICATION: See Annex 3 in CSR
4. DATA MATRIX: See Annex 3 in CSR - Reason / purpose for cross-reference:
- read-across: supporting information
- Qualifier:
- no guideline followed
- Principles of method if other than guideline:
- Enzymatic liver enzyme activity was measured after feeding the birds a tungsten supplemented diet.
- GLP compliance:
- not specified
- Specific details on test material used for the study:
- Details on properties of test surrogate or analogue material (migrated information):
no data - Dose method:
- feed
- Analytical monitoring:
- not specified
- Vehicle:
- not specified
- Details on preparation and analysis of diet:
- Experiment 1: Proprietary diet containing (per kg): 218 g protein, 0.5 mg molybdenum and 0.6 mg tungsten without addition, or with supplements of either 500 or 1000 mg tungsten/kg.
Experiment 2: Fed on a glucose-casein diet of low molybdenum content (<0.02 mg/kg) for 15 d. Then allocated to one of two dietary treatments: 1. low molybdenum control diet, 2. control diet supplemented with 150 mg tungsten/kg from day 1 and 600 mg tungsten mg tungsten/kg from day 22 - Test organisms (species):
- other: Broiler cockerels
- Details on test organisms:
- TEST ORGANISM
- Common name: Broiler cockerels (chicken)
- Source: commercial hatchery
- Age at test initiation (mean and range, SD): obtained at 1 d of age - Limit test:
- no
- Total exposure duration (if not single dose):
- 35 d
- Remarks:
- several studies were conducted with varying exposure times, one at least 35 days
- No. of animals per sex per dose and/or stage:
- Experiment 1: Sixty broiler cockerels
Experiment 2: One hundred and twenty broiler cockerels - Control animals:
- other: low molybdenum control diet
- Nominal and measured doses / concentrations:
- No data
- Details on test conditions:
- Experiment 1:
Sixty broiler cockerels were randomly distributed into three groups which were fed on a proprietary diet containing (per kg): 218 g protein, 0.5 mg molybdenum and 0.6 mg tungsten without addition, or with supplements of either 500 or 1000 mg tungsten/kg. The birds in each treatment were randomly subdivided into two groups and fed on the respective diets with or without a supplement of 4.0 mg molybdenum/kg diet.
Experiment 2:
One hundred and twenty broiler cockerels were fed on a glucose-casein diet of low molybdenum content (<0.02 mg/kg) for 15 d. The chicks were then allocated randomly to one of two dietary treatments:
1. the low-molybdenum control diet fed throughout the experiment.
2. the control diet supplemented with 150 mg tungsten/kg from day 1 and 600 mg tungsten/kg from day 22. - Details on examinations and observations:
- Experiment 1:
At 28 d of age four birds were randomly selected from each treatment and killed.
The livers were rapidly excised and analysed for tungsten, molybdenum and xanthine dehydrogenase activity.
Experiment 2:
Four chickens from each treatment were randomly selected and killed on days 1, 2, 4, 7, 11, 16, 21, 28 and 35. After killing, the intestines and livers were rapidly removed. The intestines were extruded and washed and samples from the upper jejunum taken for further analyses. The liver samples were analysed for tungsten, molybdenum and xanthine dehydrogenase activity and the intestinal samples were analysed for xanthine dehydrogenase activity. Blood samples were also taken from the chickens of the control and supplementary dietary tungsten treatments killed on day 35. These were analysed for tungsten, molybdenum, hemoglobin, uric acid and xanthine plus hypoxanthine. - Details on reproductive parameters:
- no data
- Reference substance (positive control):
- no
- Duration (if not single dose):
- 28 d
- Dose descriptor:
- LOEC
- Effect level:
- 1 000 mg/kg diet
- Conc. / dose based on:
- act. ingr.
- Basis for effect:
- other: reduced liver xanthine dehydrogenase activities
- Duration (if not single dose):
- 28 d
- Dose descriptor:
- NOEC
- Effect level:
- ca. 500 mg/kg diet
- Conc. / dose based on:
- act. ingr.
- Basis for effect:
- other: reduced liver xanthine dehydrogenase activities
- Mortality and sub-lethal effects:
- Experiment 1:
No birds died during this experiment. There was no mortality in this experiment. Supplementation of the diet with 1 g tungsten/kg significantly (P<0.01) increased liver tungsten concentrations in birds receiving no additional molybdenum. Liver xanthine dehydrogenase activities were significantly (P< 0.001) reduced in birds receiving the high dietary concentration of tungsten with no molybdenum supplement but the effect was abolished when additional molybdenum was fed.
Experiment 2:
No birds died form either dietary treatment during this experiment. By day 28 the mean body-weight gains of the eight birds remaining on the control and dietary tungsten tungsten treatments were respectively 1 000 and 864 g.
Both liver and intestinal xanthine dehydrogenase activities decreased with increasing liver tungsten concentrations. This decline in enzyme activity occurred at approximately the same rate in both tungsten treatments. Extrapolation of the data indicated that zero activity occurred in both tissues at a
tungsten concentration of approximately 25 ug/g liver.
The blood molybdenum concentrations of the control and tungsten-fed birds on day 35 were respectively 0.06 and 0.02 ug/mL, but this difference did not attain statistical significance. The blood tungsten concentrations of these groups of birds at this time were 0.1 and 15.4 ug/mL respectively and these were significantly different (P< 0.001). The plasma xanthine plus hypoxanthine concentrations in the birds on the
control and supplementary dietary tungsten treatments on day 35 were 0.5 and 12.9 mg/100 mL respectively (P<0.01). The plasma uric acid concentrations were 2.0 and 6.2 mg/100 mL respectively (P< 0.001). The mean hemoglobin concentrations of birds on these treatments were similar at 9.4 and 9.6 mg/100 mL blood respectively. - Effects on reproduction:
- no data
- Results with reference substance (positive control):
- n/a
- Reported statistics and error estimates:
- Experiment 1:
The data were analysed by analysis of variance.
Experiment 2:
The data were analysed by analysis of variance. Each day's data were analysed separately because of the changes in the doses of tungsten administered to the birds. Regression analyses relating intestinal and hepatic xanthine dehydrogenase activities to liver tungsten concentrations were also conducted. - Conclusions:
- Liver xanthine dehydrogenase activities were significantly (P< 0.001) reduced in birds receiving the high dietary concentration (1000 mg/kg diet) of tungsten
- Executive summary:
No toxicity to birds data of sufficient quality are available for tungsten trioxide (target substance). However, toxicity to birds data are available for sodium tungstate (source substance), which are used for read-across. Due to lower water solubility and lower toxicity for the target substance compared to the source substance, the resulting read-across from the source substance to the target substance is appropriate as a conservative estimate of potential toxicity for this endpoint. In addition, read-across is appropriate because the classification and labelling is more protective for the source substance than the target substance, the PBT/vPvB profile is the same, and the dose descriptors are, or are expected to be, lower for the source substance. For more details, refer to the read-across category approach description in the Category section of this IUCLID submission or Annex 3 of the CSR.
Referenceopen allclose all
Test Results:
Experiment 1
- The addition of 250 ppm sodium tungstate had little or no effect on the xanthine dehydrogenase activity of the hen tissues tested.
- 500 ppm tungsten caused a steady decline in xanthine dehydrogenase activity, which appeared to stabilize around 30 days.
- Neither level of sodium tungstate had an apparent effect on the rate of egg production or hatchability.
Experiment 2, Trial 1 and Trial 2
-Day old chicks from hens fed tungstate had significantly higher amounts of xanthine dehydrogenase in the liver and intestine than did chicks from hens receiving no tungstate.
- Chicks from hens fed the tungsten-supplemented ration grew at a significantly slower rate than did the control chicks on both the breeder ration and the broiler ration.
- When the chick ration was supplemented with 500 ppm tungsten, a slower rate of gain was observed when compared to rations containing no supplementation.
- At four weeks of age, there appeared to be no difference in the xanthine dehydrogenase activities between the chicks, regardless of the ration fed or the hen treatment
-The variation that occurred in the enzyme determinations was large, and the sample size relatively small. This may have accounted for there being no statistical differences.
Results
Table 2. Effects of diets containing W on growth and xanthine dehydrogenase activities of chicks.
Xanthine dehydrogenase activity (mm302/20 min/flask), week 6
Group | Body wt. 3 wks (g) | Body wt. 5 wks (g) | intestine | liver | kidney | pancreas |
1 | 218 | 343 | 8 | 32 | 11 | 6 |
2 | 217 | 311 | 8 | 32 | 12 | 4 |
4 | 169 | 311 | 1 | 4 | 1 | 1 |
8 | 149 | 274 | 1 | 3 | 2 | 2 |
XD levels measured after 6 weeks on the diets, using 28.3 mg liver or kidney, and 84.9 mg intestine or pancreas per flask.
- After 3 weeks, 6 chicks from Groups 8 (94 mg/kg W) were sacrificed, and analyzed for Xanthine dehydrogenase and Mo.
- The mean values for intestine, liver, kidney, and pancreas were 0.4, 2.2, 0.2, and 0.8 mm3O2/20 min. respectively for Group 8 (avg Mo 0.20 ug/g dry wt)
- Therefore, within 3 weeks, the addition of 94 mg/kg to the diet markedly depressed tissue Mo and XD activities.
- After 6 weeks, half of the uric acid normally produced by chicks was replaced by a mixture of xanthine and hypoxanthine in Group 8.
Liver molybdenum concentrations and the activity of liver xanthine dehydrogenase were markedly reduced only when the tungsten concentration of tissues approached this high concentration.
The proportion of the liver molybdenum contributing to the xanthine dehydrogenase enzyme was calculated for experiment 2 from the known specific activity of highly purified extracts of this enzyme from chicken and turkey liver These calculations indicated that at normal liver molybdenum concentrations approximately 37% of the liver molybdenum was bound to xanthine dehydrogenase, while at the lowest molybdenum concentrations observed prior to death (seen in injection groups only) only approximately 7% of the liver molybdenum was bound to the enzyme. This would suggest that these chicks were affected primarily by a tungsten toxicity rather than by a simple molybdenum deficiency.
Description of key information
Several older studies on chicken species were identified in which the birds were fed varying amounts of tungsten, in the form of sodium tungstate in their diets. The NOAELs identified from these studies ranged from approximately 45-500 mg tungsten/kg, depending on which endpoints were examined in each study. However, none of these studies were conducted with standard methodology and they were deemed to be less than reliable.
Key value for chemical safety assessment
- Long-term EC10, LC10 or NOEC for birds:
- 45 mg/kg food
Additional information
Due to similar or lower transformation/dissolution results for tungsten trioxide (the target substance) than sodium tungstate (the source substance), the resulting toxicity potential would also be expected to be similar or lower, so read-across is appropriate. In addition, read-across is justified because the classification and labeling is the same or less severe for the target substance PBT/vPvB profile is the same. Finally, the dose descriptors are, or are expected to be, sufficiently similar or higher for the target substance, and read-across to the source substance is adequately protective. For more details, refer to the read-across category approach description in the Category section of this IUCLID submission or Annex 3 of the CSR.
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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