Review Article

Engineered Nanomaterials: Knowledge Gaps in Fate, Exposure, Toxicity, and Future Directions

Table 1

Sample summary of ENM-related human effects and/or risk assessment studies.

ReferenceExposure routeENMs consideredStudy focus

Morgan [21]NADevelopment of preliminary framework for risk analysis and risk management of ENMs using expert elicitation and mental modelling

Maynard and Kuempel [2]InhalationReview of airborne nanostructured particles and occupational health

Wiesner et al. [22]NAAssessment of risks of manufactured nanomaterials

Tsuji et al. [23]Inhalation and dermalReview of risk assessment of ENMs due to inhalation and dermal routes

Lam et al. [10]InhalationCarbon nanotubesReview of carbon nanotube toxicity and assessment of potential occupational and environmental health risks

Kandlikar et al. [24]InhalationParticles less than 2.5  m in diameterHealth risk assessment of nanoparticles using expert judgment

Dankovic et al. [11]InhalationFine and ultrafine TiO2Calculation of risk of cancer using dose-response information for rats

Mueller and Nowack [3]NAAg, TiO2, and carbon nanotubesExposure modelling of ENMs in environment using life-cycle perspectives

Liao et al. [12]InhalationNano-/fine TiO2Model-based assessment for human inhalation exposure risk assessment

Kroll et al. [25]NACurrent in vitro methods in ENMs risk assessment: limitation and challenges

Shinohara et al. [26]InhalationFullerenesRisk assessment

Morimoto et al. [27]InhalationFullerenesInflammogenic effect of well-characterised fullerenes in inhalation and intratracheal instillation studies

Tervonen et al. [28]NAFullerenes, carbon nanotubes,
CdSe, Ag, and Al
Risk-based classification systems of nanomaterials

O’Brien and Cummins [29]NANADevelopment of a three-level risk assessment strategy for nanomaterials

Grieger et al. [30]NAStudy of current research priorities for nanomaterials and redefining of risk-based efforts

Christensen et al. [31]InhalationAgInvestigation of feasibility and challenges associated with conducting HHRA for Ag ENMs and identification of related data gaps

Christensen et al. [32]InhalationTiO2Investigation of feasibility and challenges associated with conducting HHRA for TiO2 ENMs and identification of related data gaps

Gangwal et al. [33]InhalationTiO2 and AgMethod development for determining nanomaterials concentrations for ToxCast in vitro testing for occupational exposure potential

Anandan and Kumar [34]OralTiO2 and AgEstimation of risk to humans due to exposure of ENMs during inadvertent ingestion of stream water using liver cell line-based toxicity data

Johnson et al. [35]OralTiO2Study on fate, behaviour, and environmental risk associated with sunscreen TiO2 ENMs; HHRA conducted for ingestion of TiO2 particles

Kumar et al. [36]InhalationENMsEmissions estimates of nanomaterials from road vehicles in megacity Delhi and associated health impacts

Kumar [37]NAENMsMaking a case for human health risk-based ranking nanomaterials in water for monitoring purposes

Kumar et al. [38]NAENMsKnown, unknowns, and awareness related to nanomaterials in Indian environment

Singh and Kumar [39]NAENMsIdentifying knowledge gaps in assessing health risks due to exposure of nanoparticles from contaminated edible plants

Khanna and Kumar [40]NAENMsIncluding nanomaterials mixtures in human health risk assessment

Frater et al. [41]NAENMsA multistakeholder perspective on the use of alternative test strategies for nanomaterial safety assessment

Savolainen et al. [42]NAENMsNanosafety in Europe 2015–2025: towards safe and sustainable nanomaterials and nanotechnology innovations

Stone et al. [43]NAENMsPrioritising nanosafety research to develop a stakeholder-driven intelligent testing strategy

HHRA: human health risk assessment; NA: not applicable; ENM: engineered nanomaterial.