Fadeel, an Associate Professor of Toxicology at the Karolinska Institute’s Division of Biochemical Toxicology, is first author of a review paper that summarizes the Stockholm Symposium (There’s plenty of room at the forum: Potential risks and safety assessment of engineered nanomaterials).
Fadeel’s review covers five major areas below:
Materials and methods: The importance of standardization
While a unified procedure to classify all nanomaterials and their applications seems unlikely, there is nevertheless an urgent need for answering some outstanding questions especially in connection to the biological effects of novel nanomaterials and the possible health and environmental problems they may cause. The two most obvious requirements concern the comparability of the methods used for monitoring of adverse effects and the materials that are subject to such investigations. Therefore, there is a need for standardized toxicological assays as well as reference materials to classify the measured effects and compare them with those from other laboratories in other countries.
Human studies of engineered nanoparticles: A comparison with air pollution
The researchers conclude that the hypothesis that systemic access of ultrafine insoluble particles may induce adverse reactions in the cardiovascular system, and other organs, leading to the onset of cardiovascular disease in human subjects, requires careful consideration. Moreover, other, not generally recognized routes of exposure to engineered nanomaterials, including the putative uptake of inhaled nanoparticles into the brain via the olfactory nerve also need to be considered, although the relevance of such clearance pathways for human exposure remains to be established.
Single-walled carbon nanotubes: Understanding and controlling their toxicity
Carbon nanotubes (CNTs) are some of the most researched nanoparticles. Their increasing use in industry has prompted a number of toxicology studies. The participants at the symposium discussed numerous studies that deal with some form of human health and biocompatibility of CNTs, especially single-walled CNTs.
Risk assessment of engineered nanomaterials:
The researchers pointed out that there is a strong likelihood that the biological activity of nanoparticles will depend on physico-chemical parameters not routinely considered in toxicity screening studies. One consequence of this would be that the regulation of human occupational exposures, which is currently based on airborne mass concentration, need to be reconsidered in light of these findings.
Regulation of the nanotechnologies: Identifying knowledge gaps
Several important ‘knowledge gaps’ were identified and discussed at the Nobel Forum minisymposium, and efforts to address these issues will be required to ensure science-based decision making and implementation of existing legislations: (i) nomenclature, definitions, and standards; (ii) hazard characterization; (iii) exposure and effects assessment; (iv) environmental fate, transport, and persistence; and (v) measurement, sampling, and monitoring of nanomaterials.