Prevention through design (PtD): selection of proven risk management measures (RMMs) to control the exposure to ENMs

摘要

The use of engineered nanomaterials (ENMs) is growing continuously due to the increasing number of applications, promoting the development of a new generation of innovative products that have created tremendous growth potential for a large number of sectors. However, along with the benefits, there is an on-going debate about their potential effects on the human health or the environment. For a comprehensive risk assessment of ENMs, information is needed with respect to the intrinsic harmfulness of the particle, likelihood of exposure, and efficacy of workplace controls. Major investments have been done so far on the characterization of the toxicological profile. However, research aiming to improve our understanding of the possible exposure, as well as on the effectiveness of common risk management measures is far less advanced. This work presents experimental data on the effectiveness of respiratory and dermal protection equipment, and local exhaustive ventilation (LEV) systems to control the exposure to ENMs in occupational settings. New experimental data on the protection factors achieved under representative exposure scenarios, as well as recommendations for the design of PPE and ECs will be presented. The testing activities were conducted after the validation of a set of standardized procedures, including the evaluation of the permeation to ENMs for dermal protective equipment, total inward leakage (TIL) inward leakage for respirators and filters, and capture efficiency for ventilation systems. The experimental work was conducted in a dedicated nano-aerosol exposure chamber where several exposure scenarios can be reproduced. The results from the test suggest that the control of exposure via inhalation is a key priority. Respirators provided medium performance levels of filtration efficiency against NMs. The performance levels determined suggest that face seal leakage, and not filter penetration, is a key parameter to be considered when working with NMs. The evaluation of dermal protective equipment showed very low permeation levels, meaning that common measures are effective. The capture efficiency of the LEV systems was demonstrated to be adequate. The data are compiled in a library of nano-specific RMMs developed using Microsoft Excel®. The library helps stakeholders to select proper measures depending of the type of ENM and process, guiding the user in the selection of proven risk management measures. The research leading to these results has received funding from the European Union's FP7 Grant Agreement n. 310584 (NanoReg project), and the LIFE project NanoRISK (LIFE ENV/ES/000178)