NANOMATERIALS - PROPOSALS OF OCCUPATIONAL EXPOSURE LIMITS IN THE WORLD AND HYGIENE STANDARDS IN POLAND

Abstract

Currently, there are no legally binding workplace exposure limits for substances in the form of nanoobjects. There are different ap proaches to risk assessment and determination of occupational exposure limits. The purpose of this article is to compare exposure levels in the work environment proposed by international organizations and world experts, as well as the assumptions and methods used for their estimation. This paper presents the proposals of the National Institute for Public Health and the Environment in the Netherlands (RIVM), the New Energy and Industrial Technology Development Organization in Japan (NEDO) and the National Institute for Occupational Safety and Health in the USA (NIOSH). The authors also discuss the reports on the levels for carbon nanotubes (Baytubes and Nanocyl) proposed by Pauluhn and Luizi, the derived no-effect levels (DNEL) complying with the REACH Regulation, proposed by experts under the 7th Framework Programme of the European Commission, coordinated by Professor Vicki Stone (ENRHES), and alternative estimation levels for poorly soluble particles by Pauluhn. The issue was also raised whether the method of determining maximum admissible concentrations in the work environment, currently used in Poland, is adequate for nanoobjects. Moreover, the introduction of nanoreference values, as proposed by RIVM, the definition of a new fraction for particles of 1-100 nm, taking into account the surface area and activity of the particles, and an adequate estimation of uncertainty factors seem to be worth considering. Other important, if not key issues are the appropriate measurement (numerical concentration, surface concentration, particle size distribution), as well as the methodology and equipment accessibility to all employers responsible for a reliable risk assessment of exposure to nanoparticles in the work environment.