Human health risks of exposure to carbon nanotubes: Keeping pace with innnovation

Abstract

The worldwide production of carbon nanotubes (CNTs) has increased substantially in the last decade as the material offer society new opportunities for effectively stronger, lighter, better electrically conductive, and more flexible products. However, concerns have been raised about (occupational) health risks due to CNT exposure, but understanding of the specific hazard potential of CNTs is complicated by its variability in structure and size. In addition, an accurate risk assessment is further hindered by difficulties in measuring CNT exposure and limited exposure data for the different stages of the CNT product life cycle. This thesis contributes to the safe(r) use of CNTs and provides scientific knowledge concerning 1) a comprehensive exposure assessment method for multi-walled (MW)CNTs, 2) the identification of activities and exposure determinates which significantly contributes to MWCNTs exposure across the product life cycle and 3) the observation of an indication of endothelial activation and an increased inflammatory reaction associated with MWCNT exposure. Based on the conclusions of this research the following recommendations are made: 1) The use of less hazardous functionalized forms of CNTs, which are identified based on physical and chemical characteristics of products, should be stimulated, 2) Conservative soft laws (soft regulatory agreements) could help society adapt to the pace of innovation safely and should be considered, and 3) A mandatory European exposure registration for the increasing number of workers exposed to CNTs is suggested as health effects are still largely unknown.