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2010
2009
Safety-by-design and engineered nanomaterials: the need to move from theory to practice
As the governance of engineered nanomaterials (ENMs) evolves, innovations in the prevention, mitigation, management, and transfer of risk shape discussion of how nanotechnology may mature and reach various marketplaces. Safety-by-Design (SbD) is one leading concept that, while equally philosophy as well as risk-based practice, can uniquely help address lingering uncertainties and concerns stemming from regulatory evaluation of ENM risk across worker, consumer, and environmental safety. This paper provides a discussion on the SbD concept across different disciplines aiming to identify different approaches and needs to meet regulatory requirements—ultimately, we argue that SbD is evolving both to meet the needs and discourse of various disciplines, and to apply within differing marketplaces and national regulatory structures. Understanding how SbD has evolved within ENM can yield a more practical application and development of SbD, and help guide or unify national and international ENM governance around a core set of safety-driven principles.
Springer
2023
Safety assessment of titanium dioxide (E171) as a food additive
The present opinion deals with an updated safety assessment of the food additive titanium dioxide (E 171) based on new relevant scientific evidence considered by the Panel to be reliable, including data obtained with TiO2 nanoparticles (NPs) and data from an extended one-generation reproductive toxicity (EOGRT) study. Less than 50% of constituent particles by number in E 171 have a minimum external dimension < 100 nm. In addition, the Panel noted that constituent particles < 30 nm amounted to less than 1% of particles by number. The Panel therefore considered that studies with TiO2 NPs < 30 nm were of limited relevance to the safety assessment of E 171. The Panel concluded that although gastrointestinal absorption of TiO2 particles is low, they may accumulate in the body. Studies on general and organ toxicity did not indicate adverse effects with either E 171 up to a dose of 1,000 mg/kg body weight (bw) per day or with TiO2 NPs (> 30 nm) up to the highest dose tested of 100 mg/kg bw per day. No effects on reproductive and developmental toxicity were observed up to a dose of 1,000 mg E 171/kg bw per day, the highest dose tested in the EOGRT study. However, observations of potential immunotoxicity and inflammation with E 171 and potential neurotoxicity with TiO2 NPs, together with the potential induction of aberrant crypt foci with E 171, may indicate adverse effects. With respect to genotoxicity, the Panel concluded that TiO2 particles have the potential to induce DNA strand breaks and chromosomal damage, but not gene mutations. No clear correlation was observed between the physico-chemical properties of TiO2 particles and the outcome of either in vitro or in vivo genotoxicity assays. A concern for genotoxicity of TiO2 particles that may be present in E 171 could therefore not be ruled out. Several modes of action for the genotoxicity may operate in parallel and the relative contributions of different molecular mechanisms elicited by TiO2 particles are not known. There was uncertainty as to whether a threshold mode of action could be assumed. In addition, a cut-off value for TiO2 particle size with respect to genotoxicity could not be identified. No appropriately designed study was available to investigate the potential carcinogenic effects of TiO2 NPs. Based on all the evidence available, a concern for genotoxicity could not be ruled out, and given the many uncertainties, the Panel concluded that E 171 can no longer be considered as safe when used as a food additive.
2021
2011
2020
2004
Rv. 83 Seljestad - Sama, Harstad. Vurdering av luftforurensning fra tunnelmunninger. NILU OR
Spredningsberegninger for tunnelforbindelse langs Rv. 83 Seljestad ¿ Sama, Harstad kommune. Det er beregnet maksimale konsentrasjoner av PM10, og NOX i tunnelene ved ugunstige trafikkforhold (rushtrafikk morgen/ettermiddag). Konsentrasjonsreduksjon som funksjon av avstand fra tunnelmunninger er vist i tabell, og konsentrasjonene er sammenlignet med nasjonalt mål og grenseverdier for luftkvalitet.
2014
2007
2017
2024
Absorpsjonslinjer i solspektra fylles igjen på grunn av rotasjonell Raman spredning (RRS). Ved analyse av UV og synlige spektra blir RRS rutinemessig korrigert for. Effekten er også tilstede ved lengre bølgelengder, men generelt avtar den når bølgelengdene øker. For spektra med høy spektraloppløsning kan effekten være av betydning. Avhengig av anvendelsen kan det være nødvendig å kvantifisere og korrigere for RRS også ved lengre bølgelengder. Av spesiell interesse er effekten i O2-A (759-769 nm) og O2-B (686-697 nm) bandene. Effekten av RRS i disse bandene blir presentert for satellittinstrumentene CarbonSat, FLEX/FLORIS, MERIS og OLCI.
2012