Activities

The responsibilities and tasks of NRLs are laid down in Regulation (EU) 2017/625, article 101.

The application of nanomaterials in food is nascent and this sector cannot be compared to any other sector subject to official controls since consolidated analytical approaches, official or reference methods and a steady body of regulations are not available.

This specificity arises from the scientific complexity underlying nanoscience and nanotechnology and from the nature of the analytical determinations in this domain. In detail, measurements dealing with nanomaterials differ from those of conventional chemical substances. For conventional chemicals, analysis consists in the qualitative identification of the analyte and the determination of its concentration. In the case of nanomaterials, the measurement process consists in a physicochemical characterization where multiple physical and chemical properties are essential measurands:

• chemical composition
• morphology
• size (up to three different parameters for particles with unequal external dimensions)
• size distribution (also this one potentially multidimensional)
• agglomeration states (reversible interactions among particles)

This last parameter is, at the same time, measurand and target of method optimisation, through the development of suitable ‘dispersion protocols’; in addition, it can affect the determination of the other parameters. For complex materials, other measurands may add such as the crystalline phase or the surface properties. If this is the basic characterization of pristine materials, in the case of food the analytical problems associated to the measurement of the (i) numerical and (ii) mass concentration comes in addition.

This complexity is enhanced by the vastness of the application field. Each single combination of physicochemical characteristics - such as chemical composition, size and size distribution, morphology, surface properties - may need the development of ad hoc methods, potentially requiring the use of different analytical techniques. Each single nanomaterial has to be dealt with as a unique analytical problem: two materials with the same chemical composition but different size and morphology may require the development of two different analytical methods.

The activities in the remit of the NRL include:

• coordination of the activities of official laboratories designated with a view of harmonising and improving analytical methods
• organisation of information meetings and training courses for the staff of official laboratories
• organisation of inter-laboratory comparative testing or proficiency tests between official laboratories
• establishment of up-to-date lists of available test and reference materials
• scientific and technical assistance to the competent authorities

In the absence of a European Union Reference Laboratory, the activities of analytical method development and harmonisation are carried out by the European Commission Joint Research Centre (Ispra, Italy) in collaboration with a group of six European expert laboratories. The NRL-Istituto Superiore di Sanità (Department of Food Safety, Nutrition and Veterinary Public Health) belongs to this expert group since its inception. The group is referred to as the Nanomaterials in Food Laboratory Group (NIF-LAG).