Exposure to airborne manufactured nanomaterials (MNMs) can best be assessed by measuring the individual exposure in the breathing zone of an individual. However, the individual exposure specifically to MNMs has not been assessable in the past due to the lack of suitable personal samplers and/or monitors. Instead, most studies related to exposure to MNMs have been carried out using either stationary measurement equipment or personal samplers to measure the particle mass based exposure, which is not very relevant for MNMs.
In recent years, a few novel sampling, monitoring and analysis techniques have been introduced that allow for an assessment of the personal exposure to MNMs, based on number or lung deposited surface area concentration or the potency of the sampled particles to generate reactive oxygen species (ROS activity). Scientifically sound investigations on their accuracy, comparability and field applicability as well as correlations between different metrics and between stationary and personal measurements are still lacking.
nanoIndEx will first identify samplers and monitors suitable for assessing personal exposure to MNMs as well as the measurable metrics. Selected samplers and monitors will be tested in laboratories for their accuracy, using spherical, monodisperse particles and for their comparability by simultaneously challenging the instruments with polydisperse aerosols of various size distributions, particle materials and morphologies, because all of these parameters can greatly affect the sampling efficiency and instrument response. Morphologies will include a variety of relevant particle shapes from (nearly) spherical to agglomerates to fibre-like particles (CNT and CNF). During all experiments, all samplers and monitors will be challenged with identical, homogenous, well characterized aerosols which allow for a direct comparison of the results with those of stationary state of the art measurement equipment, measuring in parallel. Laboratory studies will also include investigations on the effect of the personal cloud on the sampling efficiency of the instruments. Individuals will wear the samplers and monitors in a test chamber while simulating different work activities.
The samplers and monitors identified as suitable will be used in field studies in at least ten nanotechnology workplaces to investigate the applicability and comparability of the samplers and monitors under field conditions and generate a comprehensive data set on personal exposure. Stationary state of the art aerosol measurement instruments will also be employed in the field studies and the results from stationary and personal measurements compared. All field data will be evaluated following agreed protocols to feed them into existing exposure databases.
Standard operation procedures and guidance documents will be developed for the proper use of the personal samplers and monitors in field measurements and for data evaluation. These documents will be made publicly available and actively distributed among stakeholders and national and international standardization and harmonization activities, including OECD, nanoSafetyCluster, national and FP7 projects as well as national and international standardization organizations.
The project is in total divided into five work packages (WPs) as illustrated in the figure below.
- Work Package 1 deals with the management of the project and its dissemination activities.
- In Work Package 2, measurable metrics and suitable personal samplers and monitors will be identified and standard operation procedures written for using the samplers and monitors properly, based on input from WP3 and WP4.
- Samplers and monitors, identified in WP2 as suitable will be thoroughly tested in Work Package 3 in laboratories using a large variety of particle size distributions and morphologies.
- In Work Package 4 these are taken out for field studies on the comparability and applicability of the samplers and monitors. WP4 will also collect a large data set on personal exposure in nanotechnology workplaces.
- All data collected in the project will be collated in Work Package 5 and processed to be distributed to stakeholders, users of the instruments as well as national and international projects.