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Acute Toxicity: other routes

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Administrative data

Endpoint:
acute toxicity: other routes
Remarks:
intratracheal instillation
Type of information:
experimental study
Adequacy of study:
disregarded due to major methodological deficiencies
Reliability:
other: not rated according to Klimisch et al.
Rationale for reliability incl. deficiencies:
other:
Remarks:
The references contained in this summary entry represents in vivo experiments with investigations on acute toxicity (route: intratracheal instillation) with very limited value for risk assessment purposes. The references do not fulfil the criteria for quality, reliability and adequacy of experimental data for the fulfilment of data requirements under REACH and hazard assessment purposes (ECHA guidance R4 in conjunction with regulation (EC) 1907/2006, Annexes VII-X). The information contained therein were included for information purposes only.

Data source

Referenceopen allclose all

Reference Type:
publication
Title:
Role of alveolar macrophage in lung injury: Studies with ultrafine particles
Author:
Oberdörster, G. et al.
Year:
1992
Bibliographic source:
Environmental Health Perspectives 97: 193-199.
Reference Type:
publication
Title:
Increased inflammation and altered macrophage chemotactic responses caused by two ultrafine particle types
Author:
Renwick, L.C. et al.
Year:
2004
Bibliographic source:
Occup Environ Med 61:442-447.
Reference Type:
publication
Title:
Pulmonary toxicity study in rats with three forms of ultrafine-TiO2 particles: Differential responses related to surface properties
Author:
Warheit, D.B. et al.
Year:
2007
Bibliographic source:
Toxicology 230: 90-104.
Reference Type:
publication
Title:
Titanium dioxide particle - induced goblet cell hyperplasia : association with mast cells and IL-13
Author:
Ahn, M.-H. et al.
Year:
2005
Bibliographic source:
Respiratory Research 6: 34 - 42.
Reference Type:
publication
Title:
Intratracheal administration study of titanium oxide nanoparticles into rats
Author:
Mizuno, K.
Year:
2011
Bibliographic source:
Cited in:OECD Dossier on titanium dioxide Series No. 54 (2015).
Reference Type:
publication
Title:
Categorization of nano-structured titanium dioxide according to physicochemical characteristics and pulmonary toxicity
Author:
Hashizume, Naoki; Oshima, Yutaka; Nakai, Makoto; Kobayashi, Toshio; Sasaki, Takeshi; Kawaguchi, Kenji; Honda, Kazumasa; Gamo, Masashi; Yamamoto, Kazuhiro; et al.
Year:
2016
Bibliographic source:
Toxicology Reports, (2016) Vol. 3, pp. 490-500. CODEN: TROEF9. ISSN: 2214-7500.
Reference Type:
publication
Title:
Toxicogenomics analysis of mouse lung responses following exposure to titanium dioxide nanomaterials reveal their disease potential at high doses
Author:
Rahman L. , Wu D., Johnston M., Williams A., and Halappanavar S.
Year:
2017
Bibliographic source:
Mutagenesis, 2017, 32, 59–76 doi:10.1093/mutage/gew048 Original Manuscript Advance Access publication 19 October 2016

Materials and methods

Principles of method if other than guideline:
Oberdörster, G. et al. (1992):
Test substance: TiO2-F (anatase, ~ 250 nm diameter) and TiO2-D (anatase, ~ 20 nm diameter), TiO2-R (rutile, ~ 220 nm diameter), TiO2-S (rutile, 12 nm diameter). Additional phagocytized and serum coated particles were used in a re-instillation study
Doses/Concentrations:
(i )TiO2-F: 500 and 1000 µg
(ii) TiO2-D: 65, 107, 200, 500, and 1000 µg
(iii) TiO2-R: 500 µg
(iv) TiO2-S: 500 µg
No. of animals per sex per dose: 4 rats each
MMAD (GSD): not specified
Exposure duration/frequency: single administration and sacrifice after 24 hours
Negative control: 0.2 mL saline
Positive control: not specified
Method of administration: intratracheal installation under halothane anesthesia
Parameters investigated: lung lavage parameters (cell determination, cell differential, and total protein content), dosimetry (dose in alveolar space and tissue)

Renwick, L. C. et al. (2004):
Test substance: fine titanium dioxide (TiO2; diameter: 250.0 nm; surface area: 6.6 m²/g)(provided by Tioxide Ltd) and ultrafine titanium dioxide (UTiO2; diameter: 29.0 nm; surface area: 49.78 m²/g)(obtained from Degussa)
No. of animals per sex per dose: unknown number of male Wistar rats
Doses/Concentrations: 125 and 500 µg suspended in 0.5 mL sterile saline
MMAD (GSD): not specified
Exposure duration/frequency: single administration and sacrifice after 24 hours
Negative control: 0.5 mL saline
Positive control: not specified
Method of administration: intratracheal installation under halothane anesthesia
Parameters investigated: inflammation was quantified by bronchoalveolar lavage; the ability of the macrophages to phagoytose indictor fluorescent beads and to migrate towards aC5a were determined.

Warheit, D. B. et al. (2007):
Test substance:
(i) DuPont uf-1 (approx. 136 nm in diameter; surface area: 18.2 m²/g; titanium dioxide core ~ 98 % with alumina surface coating ~ 2 %)
(ii) DuPont uf-2 (approx. 149.4 nm; surface area: 35.7 m²/g; ~ 88 wt% titanium dioxide core with ~ 7 wt% amorphus silica and ~ 5 wt% alumina)
(iii) R-100 rutile type (referred to as F-1) supplied by DuPont (382 nm in diameter; surface area: 5.8 m²/g; titanium dioxide core ~ 99 % with alumina surface coating ~ 1 %)
(iv) P25 ultrafine-TiO2 particles supplied by Degussa (reffered to as Uf-3)(approx. ~ 129.4 nm in water, consisting of 100 wt% titanium dioxide (80 / 20 anatase / rutile)
Doses/Concentrations: 1 or 5 mg/kg
No. of animals per sex per dose: 4 / group dose time point rats (lung tissue studies) and 5 rats /group dose time point (bronchoalveolar lavage studies)
MMAD (GSD): not specified
Exposure duration/frequency: single administration followed by a recovery period of 24 hours, 1 week, 1 month and 3 month
Negative control: phosphate buffered saline (PBS)
Positive control: not specified
Method of administration: intratracheal installation
Parameters investigated: pulmonary inflammation, cytotoxicity, airway and lung parenchymal cell proliferation, histopathological evaluation of lung tissue

Ahn, M.-H. et al. (2005):
Test substance: TiO2 (mean diameter = 0.29 μm, DuPont, Wilmington, DE)
Doses/Concentrations: 4 mg/kg in 200 μL of endotoxin free water
No. of animals per sex per dose: 6 - 8 rats
MMAD (GSD): not specified
Exposure duration/frequency: single administration and sacrifice after 4, 24, 48 and 72 hours
Negative control: saline
Positive control: not specified
Method of administration: intratracheal installation
Parameters investigated: cell number, differential cell counts, and IL-13 measured in bronchoalveolar lavage (BAL); number of globet cells, Muc5ac (+) expressing epithelial cells and IL-13 expressing mast cells as well as Muc-1, 2 and 5ac gene transcripts (RT-PCR) were determined in trachea.

Mizuno, K. (2011):
Test substances:
(i) MT-150AW 15 nm (specific surface area: 28.2 m²/g)(hydrophilic)
(ii) MP-1133 250 nm (specific surface area: 2.4 m²/g)(hydrophilic)
(iii) MT-100TV 15 nm (specific surface area: 12.9 m²/g)(hydrophobic)
(iv) JMT-150IB 15 nm (specific surface area: 17.4 m²/g)(hydrophobic)
Doses/Concentrations: 1 and 5 mg/mL
No. of animals per sex per dose: 20 rats
MMAD (GSD): not specified
Exposure duration/frequency: single administration and sacrifice after 3 days, 1 week, 4 weeks, and 13 weeks
Negative control: 30 mM phosphate buffer solution containing 2 mg/mL of Tween®80
Positive control: AEROXIDE® P25
Method of administration: intratracheal installation
Parameters investigated: clinical signs, mortality, body weight, organ weights (lung), histopathological examination (lung, liver, spleen, cerebrum, and kidney), bronchoalveolar lavage (BAL) fluid analysis (cell fractions, lactate dehydrogenase, micro-proteins), blood biochemistry, and macroscopic examination

Hashizume, N. et al. (2016):
Test substances:
(i) AMT-100 6 nm (anatase; surface area: 250-300 m²/g; surface coating: no; volume average diameter: 185 nm, Number average diameter: 68.5 nm; Tayca)
(ii) MT-150AW 28.8x7.6 nm (rutile; surface area: 100-120 m²/g; surface coating: no; volume average diameter: 58.5 nm, Number average diameter: 28.7 nm; Tayca)
(iii) TTO-S-3 50-100x10-20 nm (rutile; surface area: 102 m²/g; surface coating: no; volume average diameter: 61.9 nm, Number average diameter: 45.8 nm; Ishihara Sangyo Kaisha)
(iv) TTO-S-3 (Coated) 50-100x10-20 nm (rutile; surface area: 93 m²/g; surface coating: Al(OH)3; volume average diameter: 241 nm, Number average diameter: 125 nm; Ishihara Sangyo Kaisha)
(v) P25 21 nm (rutile/anatase (20/80); surface area: 50±15 m²/g; surface coating: no; volume average diameter: 99.2 nm, Number average diameter: 73.8 nm; Evonik)
(vi) MP-100 1µm (rutile; surface area: 6 m²/g; surface coating: no; volume average diameter: 531 nm, Number average diameter: 289 nm; Tayca)
(vii) FTL-100 1680x130 nm (rutile; surface area: 12 m²/g; surface coating: no; volume average diameter: not calculated, Number average diameter: not calculated; Ishihara Sangyo Kaisha)
Doses/Concentration: 0.67, 2, and 6 mg/kg
No. of animals per sex per dose: 10 rats
MMAD (GSD): not specified
Exposure duration/frequency: sinlge administration and sacfrifice after 3 days, and 4 weeks
Negative control: 2 mg/ml disodium phosphate
Positive control: not specified
Method of administration: intratracheal instillation
Parameter investigated: Clinical signs and body weight, Physicochemical properties of test material (crystallinity, shape, particle size, surface area, and surface coating), bronchoalveolar lavage (BAL) fluid analyses (Differential neutrophil ratio, total cell number, concentrations of albumin, total protein content, alkaline phosphatase activity, and lactate dehydrogenase activity), realtive organ weights per body weight (lungs, liver, kidneys, spleen, and brain), histopathological responses (lung)

Rahman, L. et al. (2017):
Test substances:
(i) Hombikat UV-100 (anatase; surface area: 229-234.47 m²/g; modified; hydrophilic; primary size (cited): 8 nm; Sachtleben Chemie GmbH)
(ii) PC105 TiO2 (anatase; surface area: 90 m²/g; unmodified; primary size (cited): 20 nm, (TEM measurement: 30 nm); Crystal Global)
(iii) Tiona TiO2 (anatase; surface area: 10 m²/g; unmodified; primary size (cited): 300 nm, (TEM measurement: 100-120 nm); Crystal Global)
(iv) P25 TiO2 (rutile/anatase (81.5:18.5); surface area: 52.18-55.49 m²/g; unmodified; hydrophilic; primary size (cited): 20 nm, (TEM measurement: 18-52 nm); Evonik Degussa)
(v) UV-Titan M262 TiO2 (rutile; surface area: 51.69-50.86 m²/g; modified: Dimethicone, alumina; hydrophobic; primary size (cited): 20 nm, (TEM measurement: 18-52 nm); Sachtleben Chemie GmbH)
(vi) UV-Titan M212 TiO2 (rutile; surface area: 57.07-57-18 m²/g; modified: Glycerol, alumina; hydrophilic; primary size (cited): 21 nm, (TEM measurement: 35-70 nm); Sachtleben Chemie GmbH)
Doses/Concentration: 18 (was afterwards excluded from the results section due to a lack of significant changes), 54, 162, and 486 µg/mouse
No. of animals per sex per dose: 60
MMAD (GSD): not specified
Exposure duration/frequency: single administration and sacrifice after 1 day, 28 day, and 90 days
Negative control: MilliQ water
Positive control: not specified
Method of administration: intratracheal administration
Parameter investigated: bronchoalveolar lavage (BAL) fluid analyses (mononuclear cells, neutrophils, lymphocytes, total cells, ß-N-Acetylglucosaminidase (NAG) activity, alkaline phosphatase (ALP) activity), lung histopathology, TEM analysis (size and agglomeration state of TiO2 NPs), Dynamic light scattering analysis (DLS) (number-weighted particle aggregate sizes), Microarray analysis (differentially expressed genes (DEG), gene ontology (GO)-term analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, Ingenuity Pathway Analysis (IPA), and NextBio disease analysis)

Test material

Constituent 1
Chemical structure
Reference substance name:
Titanium dioxide
EC Number:
236-675-5
EC Name:
Titanium dioxide
Cas Number:
13463-67-7
Molecular formula:
O2Ti
IUPAC Name:
calcium carbonate
Test material form:
other: solid: bulk / nanomaterial

Test animals

Species:
other: Oberdörster(1992): rat (Fischer 344); Renwick(2004): rat (Wistar); Warheit(2007): rat (Crl:CD®(SD)IGS BR); Ahn(2005): rat (Sprague Dawley); Mizuno(2011): rat (Crl:CD (SD) (SPF animal)); Hashizume(2016): rat (F344/DuCrlCrlj); Rahman(2017): mouse (C57BL/6)
Sex:
male/female

Administration / exposure

Route of administration:
other: intratrachial instillation

Results and discussion

Effect levelsopen allclose all
Sex:
male
Remarks on result:
other:
Remarks:
Oberdörster, G. et al. (1992): ultrafine particles (below about 50 nm) of a compound of low in vivo solubility and low toxicity deposited in the alveoli of the lung enter the interstitium more readily than larger-sized-particles of the same compound. Ultrafine particles elicit a greater inflammatory response in the alveolar space as compared to larger-sized particles. Inflammatory events (polymorphnuclear neutrophils (PMN) influx, epithelial damage) mediated by alveolar macrophages are inhibited once the ultra fine particles are phagocytised.
Sex:
male
Remarks on result:
other:
Remarks:
Renwick, L. C. et al. (2004): Ultrafine particles induced more polymorphonuclear neutrophils (PMN) recruitment, epithelial damage, and cytotoxicity than their fine counterparts, exposed at equal mass. Both ultrafine and fine particles significantly impaired the phagocytic ability of alveolar macrophages. Only ultrafine particle treatment significantly enhanced the sensitivity of alveolar macrophages to chemotact towards C5a.
Sex:
male
Remarks on result:
other:
Remarks:
Warheit, D. B. et al. (2007): the ranking of lung inflammation / cytotoxicity / cell proliferation and histopathological responses was uf-3 > F-1 = uf-1 = uf-2. Uf-3 rutile / anatase TiO2 particles produced pulmonary inflammation, cytotoxicity and adverse lung tissue effects. In contrast, eposures to F-1 fine TiO2 particles or to uf-1 / uf-2 ultrafine TiO2 particle-types produced transient inflammation.
Sex:
male
Remarks on result:
other:
Remarks:
Ahn, M.-H. et al. (2005): the concentration of IL-13 in BAL fluids was higher in TiO2 treated – rats when compared to those in sham rats (p < 0.05). Pretreatment with cyclophosphamide (CPA) decreased the number of neutrophils and eosinophils in BAL fluid of TiO2 treated – rats (p < 0.05), but affected neither the percentage of periodic acid SChiff (PAS) (+) cells, nor IL-13 levels in the BAL fluids (p > 0.05). In contrast, pretreatment with dexamethasone (DEX) diminished the percentage of PAS (+) cells and the levels of IL-13 (p < 0.05). TiO2 treatment increased the IL-13 (+) mast cells (p < 0.05) in the trachea, which was suppressed by DEX (p < 0.05), but not by CPA pretreatment (p > 0.05). In addition there were significant correlations of IL-13 (+) rate of mast cells in the trachea with IL-13 concentration in BAL fluid (p < 0.01) and with the percentage of Muc5ac (+) cells in the sham and TiO2 treated rats (p < 0.05).
Sex:
male
Remarks on result:
other:
Remarks:
Mizuno, K. (2011): in conclusion, a high dose of intratracheally administered substance MT-100TV caused the strongest inflammatory response in the lung with a severity of inflammation comparable to that of the positive control substance. The severity of the change gradually decreased over time. The inflammatory changes observed in rats treated with a high dose of substance MT-150AW or JMT-150IB were milder than the inflammation observed in the rats treated with a high dose of substance MT-100TV. The inflammatory changes observed in rats treated with a high or low dose of substance MP-1133 was nearly comparable to that of the vehicle control group. In rats treated with a low dose of any of the test substances, the severity of the inflammation was comparable to that of the vehicle control group; nonetheless, alveolar macrophages were observed even at 13 weeks after test substance administration.
Sex:
male
Remarks on result:
other:
Remarks:
Hashizume, N. et al. (2016): Examination of the associations between the physicochemical characteristics of the TiO2 and the pulmonary inflammatory responses they induced revealed (1) that differences in the crystallinity or shape of the TiO2 particles were not associated with the acute pulmonary inflammatory response; (2) that particle size was associated with the acute pulmonary inflammatory response; and (3) that TiO2 particles coated with Al(OH)3 induced a greater pulmonary inflammatory response than did non-coated particles. Intratracheal administration to rats of non-coated TiO2 particles induced only acute pulmonary inflammatory responses, and within this treatment group, the acute pulmonary inflammatory response was equivalent when the particle size was the same, regardless of crystallinity or shape. In contrast, intratracheal administration to rats with coated TiO2 induced a more severe, subacute pulmonary inflammatory response compared with that produced by non-coated TiO2 particles. Overall, the present results demonstrate that physicochemical properties may be useful for predicting the pulmonary risk posed by new nano-TiO2 materials.
Sex:
female
Remarks on result:
other:
Remarks:
Rahman, L. et al. (2017): All TiO2 NPs induced transient lung inflammation (BAL fluid analysis: neutrophil influx, after one day post-exposure). However, rutile TiO2 NPs induced higher inflammation. Rutile TiO2 NPs with a hydrophilic surface coating show the highest inflammatory response. Accordingly, the rutile TiO2 NPs induced higher number of DEGs. Treatment with rutile TiO2 NPs showed increased collagen staining and fibrosis-like changes in histopathological examinations at the highest dose, after 90 days post exposure. Among the anatase TiO2 NPs, the smallest TiO2 NP with a size of 8 nm showed the strongest response. In contrast, anatase TiO2 with a size of 300 nm showed the weakest response. Cytotoxicity, measured by ß-NAG activity, increased significantly on day 1 following exposure to anatase TiO2 NPs (8 nm) and rutile TiO2 NPs (20 nm, hydrophobic coating) at the medium and high doses and in lungs exposed to rutile TiO2 NPs (20 nm hydrophilic coating) at the high-dose group in comparison with their matched controls. The ALP activity was significantly higher on day 1 in lungs of mice exposed to anatase TiO2 NPs (8 nm) and rutile TiO2 NPs (20 nm, hydrophilic coating) at the medium and high doses and in lungs exposed to anatase TiO2 NPs (8 nm) and rutile TiO2 (20 nm) at the high-dose group compared with their matched controls. ß-NAG and ALP activity decreased.

Applicant's summary and conclusion

Conclusions:
Several mechanistic studies investigated the inflammatory response of nano-sized titanium dioxide following single administration via oropharyngeal aspiration, nasal and intratracheal instillation, whole-body and nose-only inhalation. All references do not fulfil the criteria for quality, reliability and adequacy of experimental data for the fulfilment of data requirements under REACH and hazard assessment purposes. The non-physiological route of administration via intratracheal instillation is not guideline conform and not suitable to assess acute inhalation toxicity. Where applicable, a number of these studies were considered in the assessment of differences in effects elicited in the respiratory tract of surface modified and non-surface modified titanium dioxide. A comprehensive discussion is provided in an Appendix to the CSR. These references are reported in disregarded study records in summary entries, presenting some essential details for information purposes only.

Oberdörster, G. et al. (1992): Investigated mechanistic parameters, such as translocation of particles after intratracheal instillation of the test substance.

Renwick, L. C. et al. (2004): Investigated mechanistic parameters, such as phagocytosis and chemotaxis measurement of macrophages after intratracheal instillation of the test substance.

Warheit, D. B. et al. (2007): Investigated mechanistic parameters, such as bronchoalveolar lavage (BAL) fluid inflammatory markers and cell proliferation after intratracheal instillation of the test substance.

Ahn, M.-H. et al. (2005): Investigated mechanistic parameters, such as bronchoalveolar lavage (BAL) fluid values and gene expression measurements after intratracheal instillation of the test substance.

Mizuno, K (2011): The non-physiological route of administration via intratracheal instillation is not guideline conform and not suitable to assess acute inhalation toxicity. The raw data and referred tables are not included in the publication.

Hashizume, N. et al. (2016): Investigated mechanistic parameters, such as bronchoalveolar lavage (BAL) fluid inflammatory markers and cell proliferation after intratracheal instillation of the test materials.

Rahman, L. et al. (2017): The methodical setup is not adequately designed for risk assessment purposes of the test substance. Aeroxide TiO2 P25 was suspended in water; P25 has been shown to have a strong acidic (pH 3.28) effect. Intratracheal instillation of a strong acidic solution could lead to false positive findings. Clinical observations and gross necropsy were not reported. Body weight or bodyweight changes were not stated. Results are not presented as individual values or in summarised form.