Aop: 451


Each AOP should be given a descriptive title that takes the form “MIE leading to AO”. For example, “Aromatase inhibition [MIE] leading to reproductive dysfunction [AO]” or “Thyroperoxidase inhibition [MIE] leading to decreased cognitive function [AO]”. In cases where the MIE is unknown or undefined, the earliest known KE in the chain (i.e., furthest upstream) should be used in lieu of the MIE and it should be made clear that the stated event is a KE and not the MIE. More help

Interaction with lung resident cell membrane components leads to lung cancer

Short name
A short name should also be provided that succinctly summarises the information from the title. This name should not exceed 90 characters. More help
Interaction with lung cells leads to lung cancer

Graphical Representation

A graphical summary of the AOP listing all the KEs in sequence, including the MIE (if known) and AO, and the pair-wise relationships (links or KERs) between those KEs should be provided. This is easily achieved using the standard box and arrow AOP diagram (see this page for example). The graphical summary is prepared and uploaded by the user (templates are available) and is often included as part of the proposal when AOP development projects are submitted to the OECD AOP Development Workplan. The graphical representation or AOP diagram provides a useful and concise overview of the KEs that are included in the AOP, and the sequence in which they are linked together. This can aid both the process of development, as well as review and use of the AOP (for more information please see page 19 of the Users' Handbook).If you already have a graphical representation of your AOP in electronic format, simple save it in a standard image format (e.g. jpeg, png) then click ‘Choose File’ under the “Graphical Representation” heading, which is part of the Summary of the AOP section, to select the file that you have just edited. Files must be in jpeg, jpg, gif, png, or bmp format. Click ‘Upload’ to upload the file. You should see the AOP page with the image displayed under the “Graphical Representation” heading. To remove a graphical representation file, click 'Remove' and then click 'OK.'  Your graphic should no longer be displayed on the AOP page. If you do not have a graphical representation of your AOP in electronic format, a template is available to assist you.  Under “Summary of the AOP”, under the “Graphical Representation” heading click on the link “Click to download template for graphical representation.” A Powerpoint template file should download via the default download mechanism for your browser. Click to open this file; it contains a Powerpoint template for an AOP diagram and instructions for editing and saving the diagram. Be sure to save the diagram as jpeg, jpg, gif, png, or bmp format. Once the diagram is edited to its final state, upload the image file as described above. More help


List the name and affiliation information of the individual(s)/organisation(s) that created/developed the AOP. In the context of the OECD AOP Development Workplan, this would typically be the individuals and organisation that submitted an AOP development proposal to the EAGMST. Significant contributors to the AOP should also be listed. A corresponding author with contact information may be provided here. This author does not need an account on the AOP-KB and can be distinct from the point of contact below. The list of authors will be included in any snapshot made from an AOP. More help

Penny Nymark1

Hanna L. Karlsson1

Sabina Halappanavar2

Ulla Vogel3,4

1 Institute of Environmental Medicine, Karolinska Institute, Stockholm, Sweden

2 Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON, Canada

3 National Research Centre for the Working Environment, Copenhagen, Denmark

4 DTU Health Tech, Technical University of Denmark, Kgs. Lyngby, Denmark

Funding: Swedish Fund for Research without Animals (grants N0005-2020 and F0005-2021)

Point of Contact

Indicate the point of contact for the AOP-KB entry itself. This person is responsible for managing the AOP entry in the AOP-KB and controls write access to the page by defining the contributors as described below. Clicking on the name will allow any wiki user to correspond with the point of contact via the email address associated with their user profile in the AOP-KB. This person can be the same as the corresponding author listed in the authors section but isn’t required to be. In cases where the individuals are different, the corresponding author would be the appropriate person to contact for scientific issues whereas the point of contact would be the appropriate person to contact about technical issues with the AOP-KB entry itself. Corresponding authors and the point of contact are encouraged to monitor comments on their AOPs and develop or coordinate responses as appropriate.  More help
Penny Nymark   (email point of contact)


List user names of all  authors contributing to or revising pages in the AOP-KB that are linked to the AOP description. This information is mainly used to control write access to the AOP page and is controlled by the Point of Contact.  More help
  • Penny Nymark
  • Sabina Halappanavar


The status section is used to provide AOP-KB users with information concerning how actively the AOP page is being developed, what type of use or input the authors feel comfortable with given the current level of development, and whether it is part of the OECD AOP Development Workplan and has been reviewed and/or endorsed. “Author Status” is an author defined field that is designated by selecting one of several options from a drop-down menu (Table 3). The “Author Status” field should be changed by the point of contact, as appropriate, as AOP development proceeds. See page 22 of the User Handbook for definitions of selection options. More help
Author status OECD status OECD project SAAOP status
Under development: Not open for comment. Do not cite
This AOP was last modified on May 25, 2022 09:36
The date the AOP was last modified is automatically tracked by the AOP-KB. The date modified field can be used to evaluate how actively the page is under development and how recently the version within the AOP-Wiki has been updated compared to any snapshots that were generated. More help

Revision dates for related pages

Page Revision Date/Time
Substance interaction with the lung resident cell membrane components May 04, 2022 12:11
Increased, secretion of proinflammatory mediators January 25, 2022 15:50
Increased, recruitment of inflammatory cells January 25, 2022 15:52
Increase, Cytotoxicity (epithelial cells) September 16, 2017 10:16
Increased, Reactive oxygen species November 27, 2017 13:15
Secondary genotoxicity May 25, 2022 05:25
Increased, DNA damage and mutation August 13, 2019 05:41
Increase, Cell Proliferation June 23, 2021 12:28
Lung cancer August 13, 2019 05:34
Interaction with the lung cell membrane leads to Increased proinflammatory mediators December 15, 2021 09:26
Interaction with the lung cell membrane leads to Increased, Reactive oxygen species May 25, 2022 05:44
Increased proinflammatory mediators leads to Recruitment of inflammatory cells December 07, 2021 10:28
Interaction with the lung cell membrane leads to Increased, DNA damage and mutation May 25, 2022 05:47
Increase, Cytotoxicity (epithelial cells) leads to Secondary genotoxicity May 25, 2022 05:51
Recruitment of inflammatory cells leads to Increase, Cytotoxicity (epithelial cells) May 25, 2022 05:32
Increase, Cytotoxicity (epithelial cells) leads to Increased, Reactive oxygen species May 25, 2022 05:35
Increased, Reactive oxygen species leads to Secondary genotoxicity May 25, 2022 05:35
Secondary genotoxicity leads to Increased, DNA damage and mutation May 25, 2022 05:35
Increased, DNA damage and mutation leads to Increase, Cell Proliferation July 03, 2019 11:53
Increase, Cell Proliferation leads to Lung cancer July 03, 2019 11:53
nanoparticles December 21, 2016 09:40
welding fumes May 25, 2022 07:02
Carbon black May 25, 2022 07:03
Diesel engine exhaust September 28, 2021 08:55
UV-activated Titanium dioxide nanoparticles February 15, 2017 03:49


In the abstract section, authors should provide a concise and informative summation of the AOP under development that can stand-alone from the AOP page. Abstracts should typically be 200-400 words in length (similar to an abstract for a journal article). Suggested content for the abstract includes the following: The background/purpose for initiation of the AOP’s development (if there was a specific intent) A brief description of the MIE, AO, and/or major KEs that define the pathway A short summation of the overall WoE supporting the AOP and identification of major knowledge gaps (if any) If a brief statement about how the AOP may be applied (optional). The aim is to capture the highlights of the AOP and its potential scientific and regulatory relevance More help

This AOP was developed and first presented in Nymark et al. 2021.

The particulate fraction of diesel exhaust is known to be required for carcinogenesis, since filtered exhaust does not cause lung cancer in rodents (Brightwell et al., 1989). Inhaled, nanosized particles deposit primarily in the alveolar region, where clearance is low, and lead to prolonged particle retention enabling particle-bio interaction (Oberdörster et al., 2005; Gaté et al., 2017). Interaction between particles and lung resident cell membrane components (Figure 1A below in the Background section, MIE) leads to inflammation (KE1A) which is proportional to the total deposited surface area (Schmid and Stoeger, 2016; Danielsen et al., 2020; Kokot et al., 2020). The persistence of particles results in long-lasting inflammation (Hougaard et al., 2010; Chézeau et al., 2018). Metabolic activity of pro-inflammatory cells induces formation of ROS, which may also be augmented by the surface reactivity of particles themselves (Jacobsen et al., 2008b; Bendtsen et al., 2020). The sustained inflammatory signaling and concomitant synthesis of reactive radicals, cause a chronic state of oxidant-antioxidant imbalance and loss of protective mechanisms, potentially resulting in secondary genotoxicity (KE1B) (Evans et al., 2019a). Diesel exhaust consists of nanosized particles of inorganic and organic carbon with associated metal oxides and polyaromatic hydrocarbons (PAHs) (Taxell and Santonen, 2016; Bendtsen et al., 2020). Both the carbon core and solvent-extractable fractions containing PAHs are mutagenic in vivo and several metal (oxides) have been classified as (possibly) carcinogenic (IARC, 2006, 2012b; Hashimoto et al., 2007). It is possible that such genotoxic agents leach from the pulmonary deposited particles leading to activation of alternative AOPs associated with the formation of bulky DNA adducts and resulting in accumulation of mutations (Li and Nel, 2006) as indicated by the alternative path in Figure 1A below in the Background section (in gray) (Sasaki et al., 2020). In addition, the insoluble carbon core generates particle-induced ROS leading to oxidative stress (KE1C) (Bendtsen et al., 2020; Gren et al., 2020). In a recent study of five diesel exhaust particles designed to differ in chemical composition, DNA strand breaks (KE2) in bronchoalveolar lavage cells were found to correlate with the ROS forming capacity of the particles (Bendtsen et al., 2020). Similarly, carbon black generates surface-dependent ROS, causing oxidative DNA damage (KE2) and mutagenicity (KE3) in vivo and in vitro (Jacobsen et al., 2008b). Finally, direct interactions between nanosized particles and DNA or the mitotic spindle are also possible, and the AOP features a direct link between the MIE and mutagenicity, i.e., KE3 (Buliaková et al., 2017; Patel et al., 2017).

Background (optional)

This optional subsection should be used to provide background information for AOP reviewers and users that is considered helpful in understanding the biology underlying the AOP and the motivation for its development. The background should NOT provide an overview of the AOP, its KEs or KERs, which are captured in more detail below. Examples of potential uses of the optional background section are listed on pages 24-25 of the User Handbook. More help

Lung cancer, one of the most common and deadly forms of cancer, is in some cases associated with exposure to certain types of particles. With the rise of nanotechnology, there is concern that some engineered nanoparticles may be among such particles. In the absence of epidemiological evidence, assessment of nanoparticle carcinogenicity is currently performed on a time-consuming case-by-case basis, relying mainly on animal experiments. Non-animal alternatives exist, including a few validated cell-based methods accepted for regulatory risk assessment of nanoparticles. Furthermore, new approach methodologies (NAMs), focused on carcinogenic mechanisms and capable of handling the increasing numbers of nanoparticles, have been developed. However, such alternative methods are mainly applied as weight-of-evidence linked to generally required animal data, since challenges remain regarding interpretation of the results. These challenges may be more easily overcome by the novel Adverse Outcome Pathway (AOP) framework, which provides a basis for validation and uptake of alternative mechanism-focused methods in risk assessment. Here, we propose an AOP for lung cancer induced by nanosized foreign matter, anchored to a selection of 18 standardized methods and NAMs for in silico- and in vitro-based integrated assessment of lung carcinogenicity (Figure 1). The AOP provides a basis for development of AOP-aligned alternative methods-based integrated testing strategies for assessment of nanoparticle-induced lung cancer.

Adverse Outcome Pathway Development for Assessment of Lung Carcinogenicity by Nanoparticles

Figure 1. A putative AOP for pulmonary deposition and retention of nanosized foreign matter leading to lung cancer, including anchored in silico and in vitro methods. (A) A putative AOP developed based on information and knowledge about the process-generated and engineered nanoparticles diesel exhaust, carbon black, and TiO2. Suggested relevant existing KEs in the AOP-Wiki, that could serve for informing development of the proposed AOP, are mentioned within parentheses. (B) The AOP supports integrated application of in silico- and in vitro-based standard OECD tests with new approach methodologies (NAMs), including models/approaches for prediction of deposited dose, detection of ROS generation, inflammation, DNA damage, mutations, and cell transformation. Examples of specific assays are provided at the bottom. MIE, molecular initiating event; KE, key event; AO, adverse outcome; AOP, adverse outcome pathway; IC-PMS, inductively coupled plasma mass spectrometry; AAS, atomic absorption spectroscopy; TEM, transmission electron microscopy; ROS, reactive oxygen species; DCFH-DA, 2'-7'dichlorofluorescin diacetate; GSH, glutathione; ELISA, enzyme-linked immunosorbent assay; HT, high-throughput; FPG, formamidopyrimidine DNA glycosylase; OECD, Organization for Economic Co-operation and Development; HPRT, hypoxanthine phosphorybosyl transferase; TK, thymidine kinase; FE1-MML, FE1-MutaMouse lung epithelial cells.

Summary of the AOP

This section is for information that describes the overall AOP. The information described in section 1 is entered on the upper portion of an AOP page within the AOP-Wiki. This is where some background information may be provided, the structure of the AOP is described, and the KEs and KERs are listed. More help


Molecular Initiating Events (MIE)
An MIE is a specialised KE that represents the beginning (point of interaction between a stressor and the biological system) of an AOP. More help
Key Events (KE)
This table summarises all of the KEs of the AOP. This table is populated in the AOP-Wiki as KEs are added to the AOP. Each table entry acts as a link to the individual KE description page.  More help
Adverse Outcomes (AO)
An AO is a specialised KE that represents the end (an adverse outcome of regulatory significance) of an AOP.  More help
Sequence Type Event ID Title Short name
MIE 1495 Substance interaction with the lung resident cell membrane components Interaction with the lung cell membrane
KE 1496 Increased, secretion of proinflammatory mediators Increased proinflammatory mediators
KE 1497 Increased, recruitment of inflammatory cells Recruitment of inflammatory cells
KE 780 Increase, Cytotoxicity (epithelial cells) Increase, Cytotoxicity (epithelial cells)
KE 1115 Increased, Reactive oxygen species Increased, Reactive oxygen species
KE 2006 Secondary genotoxicity Secondary genotoxicity
KE 1669 Increased, DNA damage and mutation Increased, DNA damage and mutation
KE 870 Increase, Cell Proliferation Increase, Cell Proliferation
AO 1670 Lung cancer Lung cancer

Relationships Between Two Key Events (Including MIEs and AOs)

This table summarises all of the KERs of the AOP and is populated in the AOP-Wiki as KERs are added to the AOP. Each table entry acts as a link to the individual KER description page.To add a key event relationship click on either Add relationship: events adjacent in sequence or Add relationship: events non-adjacent in sequence.For example, if the intended sequence of KEs for the AOP is [KE1 > KE2 > KE3 > KE4]; relationships between KE1 and KE2; KE2 and KE3; and KE3 and KE4 would be defined using the add relationship: events adjacent in sequence button.  Relationships between KE1 and KE3; KE2 and KE4; or KE1 and KE4, for example, should be created using the add relationship: events non-adjacent button. This helps to both organize the table with regard to which KERs define the main sequence of KEs and those that provide additional supporting evidence and aids computational analysis of AOP networks, where non-adjacent KERs can result in artifacts (see Villeneuve et al. 2018; DOI: 10.1002/etc.4124).After clicking either option, the user will be brought to a new page entitled ‘Add Relationship to AOP.’ To create a new relationship, select an upstream event and a downstream event from the drop down menus. The KER will automatically be designated as either adjacent or non-adjacent depending on the button selected. The fields “Evidence” and “Quantitative understanding” can be selected from the drop-down options at the time of creation of the relationship, or can be added later. See the Users Handbook, page 52 (Assess Evidence Supporting All KERs for guiding questions, etc.).  Click ‘Create [adjacent/non-adjacent] relationship.’  The new relationship should be listed on the AOP page under the heading “Relationships Between Two Key Events (Including MIEs and AOs)”. To edit a key event relationship, click ‘Edit’ next to the name of the relationship you wish to edit. The user will be directed to an Editing Relationship page where they can edit the Evidence, and Quantitative Understanding fields using the drop down menus. Once finished editing, click ‘Update [adjacent/non-adjacent] relationship’ to update these fields and return to the AOP page.To remove a key event relationship to an AOP page, under Summary of the AOP, next to “Relationships Between Two Key Events (Including MIEs and AOs)” click ‘Remove’ The relationship should no longer be listed on the AOP page under the heading “Relationships Between Two Key Events (Including MIEs and AOs)”. More help

Network View

The AOP-Wiki automatically generates a network view of the AOP. This network graphic is based on the information provided in the MIE, KEs, AO, KERs and WoE summary tables. The width of the edges representing the KERs is determined by its WoE confidence level, with thicker lines representing higher degrees of confidence. This network view also shows which KEs are shared with other AOPs. More help


The stressor field is a structured data field that can be used to annotate an AOP with standardised terms identifying stressors known to trigger the MIE/AOP. Most often these are chemical names selected from established chemical ontologies. However, depending on the information available, this could also refer to chemical categories (i.e., groups of chemicals with defined structural features known to trigger the MIE). It can also include non-chemical stressors such as genetic or environmental factors. Although AOPs themselves are not chemical or stressor-specific, linking to stressor terms known to be relevant to different AOPs can aid users in searching for AOPs that may be relevant to a given stressor. More help

Life Stage Applicability

Identify the life stage for which the KE is known to be applicable. More help

Taxonomic Applicability

Latin or common names of a species or broader taxonomic grouping (e.g., class, order, family) can be selected. In many cases, individual species identified in these structured fields will be those for which the strongest evidence used in constructing the AOP was available in relation to this KE. More help
Term Scientific Term Evidence Link
human Homo sapiens High NCBI

Sex Applicability

The authors must select from one of the following: Male, female, mixed, asexual, third gender, hermaphrodite, or unspecific. More help

Overall Assessment of the AOP

This section addresses the relevant biological domain of applicability (i.e., in terms of taxa, sex, life stage, etc.) and WoE for the overall AOP as a basis to consider appropriate regulatory application (e.g., priority setting, testing strategies or risk assessment). The goal of the overall assessment is to provide a high level synthesis and overview of the relative confidence in the AOP and where the significant gaps or weaknesses are (if they exist). Users or readers can drill down into the finer details captured in the KE and KER descriptions, and/or associated summary tables, as appropriate to their needs.Assessment of the AOP is organised into a number of steps. Guidance on pages 59-62 of the User Handbook is available to facilitate assignment of categories of high, moderate, or low confidence for each consideration. While it is not necessary to repeat lengthy text that appears elsewhere in the AOP description (or related KE and KER descriptions), a brief explanation or rationale for the selection of high, moderate, or low confidence should be made. More help

Domain of Applicability

The relevant biological domain(s) of applicability in terms of sex, life-stage, taxa, and other aspects of biological context are defined in this section. Biological domain of applicability is informed by the “Description” and “Biological Domain of Applicability” sections of each KE and KER description (see sections 2G and 3E for details). In essence the taxa/life-stage/sex applicability is defined based on the groups of organisms for which the measurements represented by the KEs can feasibly be measured and the functional and regulatory relationships represented by the KERs are operative.The relevant biological domain of applicability of the AOP as a whole will nearly always be defined based on the most narrowly restricted of its KEs and KERs. For example, if most of the KEs apply to either sex, but one is relevant to females only, the biological domain of applicability of the AOP as a whole would be limited to females. While much of the detail defining the domain of applicability may be found in the individual KE and KER descriptions, the rationale for defining the relevant biological domain of applicability of the overall AOP should be briefly summarised on the AOP page. More help

Essentiality of the Key Events

An important aspect of assessing an AOP is evaluating the essentiality of its KEs. The essentiality of KEs can only be assessed relative to the impact of manipulation of a given KE (e.g., experimentally blocking or exacerbating the event) on the downstream sequence of KEs defined for the AOP. Consequently evidence supporting essentiality is assembled on the AOP page, rather than on the independent KE pages that are meant to stand-alone as modular units without reference to other KEs in the sequence.The nature of experimental evidence that is relevant to assessing essentiality relates to the impact on downstream KEs and the AO if upstream KEs are prevented or modified. This includes: Direct evidence: directly measured experimental support that blocking or preventing a KE prevents or impacts downstream KEs in the pathway in the expected fashion. Indirect evidence: evidence that modulation or attenuation in the magnitude of impact on a specific KE (increased effect or decreased effect) is associated with corresponding changes (increases or decreases) in the magnitude or frequency of one or more downstream KEs.When assembling the support for essentiality of the KEs, authors should organise relevant data in a tabular format. The objective is to summarise briefly the nature and numbers of investigations in which the essentiality of KEs has been experimentally explored either directly or indirectly. See pages 50-51 in the User Handbook for further definitions and clarifications.  More help

Evidence Assessment

The biological plausibility, empirical support, and quantitative understanding from each KER in an AOP are assessed together.  Biological plausibility of each of the KERs in the AOP is the most influential consideration in assessing WoE or degree of confidence in an overall hypothesised AOP for potential regulatory application (Meek et al., 2014; 2014a). Empirical support entails consideration of experimental data in terms of the associations between KEs – namely dose-response concordance and temporal relationships between and across multiple KEs. It is examined most often in studies of dose-response/incidence and temporal relationships for stressors that impact the pathway. While less influential than biological plausibility of the KERs and essentiality of the KEs, empirical support can increase confidence in the relationships included in an AOP. For clarification on how to rate the given empirical support for a KER, as well as examples, see pages 53- 55 of the User Handbook.  More help

Quantitative Understanding

Some proof of concept examples to address the WoE considerations for AOPs quantitatively have recently been developed, based on the rank ordering of the relevant Bradford Hill considerations (i.e., biological plausibility, essentiality and empirical support) (Becker et al., 2017; Becker et al, 2015; Collier et al., 2016). Suggested quantitation of the various elements is expert derived, without collective consideration currently of appropriate reporting templates or formal expert engagement. Though not essential, developers may wish to assign comparative quantitative values to the extent of the supporting data based on the three critical Bradford Hill considerations for AOPs, as a basis to contribute to collective experience.Specific attention is also given to how precisely and accurately one can potentially predict an impact on KEdownstream based on some measurement of KEupstream. This is captured in the form of quantitative understanding calls for each KER. See pages 55-56 of the User Handbook for a review of quantitative understanding for KER's. More help

Considerations for Potential Applications of the AOP (optional)

At their discretion, the developer may include in this section discussion of the potential applications of an AOP to support regulatory decision-making. This may include, for example, possible utility for test guideline development or refinement, development of integrated testing and assessment approaches, development of (Q)SARs / or chemical profilers to facilitate the grouping of chemicals for subsequent read-across, screening level hazard assessments or even risk assessment. While it is challenging to foresee all potential regulatory application of AOPs and any application will ultimately lie within the purview of regulatory agencies, potential applications may be apparent as the AOP is being developed, particularly if it was initiated with a particular application in mind. This optional section is intended to provide the developer with an opportunity to suggest potential regulatory applications and describe his or her rationale.To edit the “Considerations for Potential Applications of the AOP” section, on an AOP page, in the upper right hand menu, click ‘Edit.’ This brings you to a page entitled, “Editing AOP.” Scroll down to the “Considerations for Potential Applications of the AOP” section, where a text entry box allows you to submit text. In the upper right hand menu, click ‘Update AOP’ to save your changes and return to the AOP page or 'Update and continue' to continue editing AOP text sections.  The new text should appear under the “Considerations for Potential Applications of the AOP” section on the AOP page. More help


List the bibliographic references to original papers, books or other documents used to support the AOP. More help

Nymark P, Karlsson HL, Halappanavar S, Vogel U. Adverse Outcome Pathway Development for Assessment of Lung Carcinogenicity by Nanoparticles. Front Toxicol. 2021 Apr 29;3:653386. eCollection 2021.

Bendtsen, K. M., Gren, L., Malmborg, V. B., Shukla, P. C., Tunér, M., Essig, Y. J., et al. (2020). Particle characterization and toxicity in C57BL/6 mice following instillation of five different diesel exhaust particles designed to differ in physicochemical properties. Part Fibre Toxicol. 17:38. doi: 10.1186/s12989-020-00369-9

Brightwell, J., Fouiliet, X., Cassano-Zoppi, A.-L., Bernstein, D., Crawley, F., Duchosal, F., et al. (1989). Tumours of the respiratory tract in rats and hamsters following chronic inhalation of engine exhaust emissions. J. Appl. Toxicol. 9, 23–31. doi: 10.1002/jat.2550090106

Buliaková, B., Mesárošová, M., Bábelová, A., Šelc, M., Némethová, V., Šebová, L., et al. (2017). Surface-modified magnetite nanoparticles act as aneugen-like spindle poison. Nanomedicine 13, 69–80. doi: 10.1016/j.nano.2016.08.027

Chézeau, L., Sébillaud, S., Safar, R., Seidel, C., Dembélé, D., Lorcin, M., et al. (2018). Short- and long-term gene expression profiles induced by inhaled TiO2 nanostructured aerosol in rat lung. Toxicol. Appl. Pharmacol. 356, 54–64. doi: 10.1016/j.taap.2018.07.013

Danielsen, P. H., Knudsen, K. B., Štrancar, J., Umek, P., Koklič, T., Garvas, M., et al. (2020). Effects of physicochemical properties of TiO2 nanomaterials for pulmonary inflammation, acute phase response and alveolar proteinosis in intratracheally exposed mice. Toxicol. Appl. Pharmacol. 386:114830. doi: 10.1016/j.taap.2019.114830

Evans, S. J., Clift, M. J. D., Singh, N., Wills, J. W., Hondow, N., Wilkinson, T. S., et al. (2019a). In vitro detection of in vitro secondary mechanisms of genotoxicity induced by engineered nanomaterials. Part. Fibre Toxicol. 16:8. doi: 10.1186/s12989-019-0291-7

Gaté, L., Disdier, C., Cosnier, F., Gagnaire, F., Devoy, J., Saba, W., et al. (2017). Biopersistence and translocation to extrapulmonary organs of titanium dioxide nanoparticles after subacute inhalation exposure to aerosol in adult and elderly rats. Toxicol. Lett. 265, 61–69. doi: 10.1016/j.toxlet.2016.11.009

Gren, L., Malmborg, V. B., Jacobsen, N. R., Shukla, P. C., Bendtsen, K. M., Eriksson, A. C., et al. (2020). Effect of renewable fuels and intake O2 concentration on diesel engine emission characteristics and Reactive Oxygen Species (ROS) formation. Atmosphere 11:641. 10.3390/atmos11060641

Hashimoto, A. H., Amanuma, K., Hiyoshi, K., Sugawara, Y., Goto, S., Yanagisawa, R., et al. (2007). Mutations in the lungs of gpt delta transgenic mice following inhalation of diesel exhaust. Environ. Mol. Mutagen 48, 682–693. doi: 10.1002/em.20335

Hougaard, K. S., Jackson, P., Jensen, K. A., Sloth, J. J., Löschner, K., Larsen, E. H., et al. (2010). Effects of prenatal exposure to surface-coated nanosized titanium dioxide (UV-Titan). A study in mice. Part Fibre Toxicol. 7:16. doi: 10.1186/1743-8977-7-16

IARC (2006). Cobalt in Hard Metals and Cobalt Sulfate, Gallium Arsenide, Indium Phosphideand Vanadium Pentoxide. Monograph 86. Available online at:

IARC (2010). Carbon Black, Titanium Dioxide, and Talc.Monograph 93. Available online at:

IARC (2012a). Diesel and Gasoline Engine Exhausts and Some Nitroarenes. Monograph 105. Available online at:

IARC (2012b). Review of Human Carcinogens (Package of 6 Volumes: A,B,C,D,E,F). Monograph 100. Available online at:: uploads/2018/06/mono100C-10.pdf

IARC (2014). Some Nanomaterials and Some Fibres. Monograph 111. Available online at::

Jacobsen, N. R., Pojana, G., White, P., Møller, P., Cohn, C. A., Smith Korsholm, K., et al. (2008b). Genotoxicity, cytotoxicity, and reactive oxygen species induced by single-walled carbon nanotubes and C60 fullerenes in the FE1-Muta™Mouse lung epithelial cells. Environ. Mol. Mutagen 49, 476–487. doi: 10.1002/em.20406

Kokot, H., Kokot, B., Sebastijanović, A., Voss, C., Podlipec, R., Zawilska, P., et al. (2020). Prediction of chronic inflammation for inhaled particles: the impact of material cycling and quarantining in the lung epithelium. Adv. Mater. 32:2003913. doi: 10.1002/adma.202003913

Li, N., and Nel, A. E. (2006). The cellular impacts of diesel exhaust particles: beyond inflammation and death. Eur. Respir. J. 27, 667–668. doi: 10.1183/09031936.06.00025006

Oberdörster, G., Oberdörster, E., and Oberdörster, J. (2005). Nanotoxicology: an emerging discipline evolving from studies of ultrafine particles. Environ. Health Perspect. 113, 823–839. doi: 10.1289/ehp.7339

Patel, S., Patel, P., and Bakshi, S. R. (2017). Titanium dioxide nanoparticles: an in vitro study of DNA binding, chromosome aberration assay, and comet assay. Cytotechnology 69, 245–263. doi: 10.1007/s10616-016-0054-3

Sasaki, J. C., Allemang, A., Bryce, S. M., Custer, L., Dearfield, K. L., Dietz, Y., et al. (2020). Application of the adverse outcome pathway framework to genotoxic modes of action. Environ. Mol. Mutagen. 61, 114–134. doi: 10.1002/em.22339

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