Julia Fabrega

Bio: Julia Fabrega is an academic researcher from University of Exeter. The author has contributed to research in topics: Food safety & European union. The author has an hindex of 3, co-authored 3 publications receiving 1155 citations.

Sequestration of zinc from zinc oxide nanoparticles and life cycle effects in the sediment dweller amphipod Corophium volutator.

Abstract: We studied the effects of ZnO nanoparticles [ZnO NPs, primary particle size 35 ± 10 nm (circular diameter, TEM)], bulk [160 ± 81 nm (circular diameter, TEM)], and Zn ions (from ZnCl2) on mortality, growth, and reproductive endpoints in the sediment dwelling marine amphipod Corophium volutator over a complete lifecycle (100 days). ZnO NPs were characterized by size, aggregation, morphology, dissolution, and surface properties. ZnO NPs underwent aggregation and partial dissolution in the seawater exposure medium, resulting in a size distribution that ranged in size from discrete nanoparticles to the largest aggregate of several micrometers. Exposure via water to all forms of zinc in the range of 0.2–1.0 mg L–1 delayed growth and affected the reproductive outcome of the exposed populations. STEM-EDX analysis was used to characterize insoluble zinc precipitates (sphaerites) of high sulfur content, which accumulated in the hepatopancreas following exposures. The elemental composition of the sphaerites did not ...

Tracing bioavailability of ZnO nanoparticles using stable isotope labeling.

Abstract: Zinc oxide nanoparticles (ZnO NPs) are widely used in commercial products and knowledge of their environmental fate is a priority for ecological protection. Here we synthesized model ZnO NPs that were made from and thus labeled with the stable isotope 68Zn and this enables highly sensitive and selective detection of labeled components against high natural Zn background levels. We combine high precision stable isotope measurements and novel bioimaging techniques to characterize parallel water-borne exposures of the common mudshrimp Corophium volutator to 68ZnO NPs, bulk 68ZnO, and soluble 68ZnCl2 in the presence of sediment. C. volutator is an important component of coastal ecosystems where river-borne NPs will accumulate and is used on a routine basis for toxicity assessments. Our results demonstrate that ionic Zn from ZnO NPs is bioavailable to C. volutator and that Zn uptake is active. Bioavailability appears to be governed primarily by the dissolved Zn content of the water, whereby Zn uptake occurs via...

Theme (concept) paper – Advancing the Environmental Risk Assessment of Chemicals to Better Protect Insect Pollinators (IPol‐ERA)

Abstract: EFSA Supporting PublicationsVolume 19, Issue 5 E200505E Technical reportOpen Access Theme (concept) paper – Advancing the Environmental Risk Assessment of Chemicals to Better Protect Insect Pollinators (IPol-ERA) European Food Safety Authority (EFSA), Corresponding Author European Food Safety Authority (EFSA) [email protected] Correspondence:[email protected]Search for more papers by this authorDomenica Auteri, Domenica AuteriSearch for more papers by this authorYann Devos, Yann DevosSearch for more papers by this authorJulia Fabrega, Julia FabregaSearch for more papers by this authorSteve Pagani, Steve PaganiSearch for more papers by this authorAgnès Rortais, Agnès RortaisSearch for more papers by this authorGuilhem de Seze, Guilhem de SezeSearch for more papers by this authorClaudia Heppner, Claudia HeppnerSearch for more papers by this authorMarta Hugas, Marta HugasSearch for more papers by this author European Food Safety Authority (EFSA), Corresponding Author European Food Safety Authority (EFSA) [email protected] Correspondence:[email protected]Search for more papers by this authorDomenica Auteri, Domenica AuteriSearch for more papers by this authorYann Devos, Yann DevosSearch for more papers by this authorJulia Fabrega, Julia FabregaSearch for more papers by this authorSteve Pagani, Steve PaganiSearch for more papers by this authorAgnès Rortais, Agnès RortaisSearch for more papers by this authorGuilhem de Seze, Guilhem de SezeSearch for more papers by this authorClaudia Heppner, Claudia HeppnerSearch for more papers by this authorMarta Hugas, Marta HugasSearch for more papers by this author First published: 31 May 2022 https://doi.org/10.2903/sp.efsa.2022.e200505 Amendment: Authorship of this technical report was rearranged on the 27th of June 2022. Disclaimer: This document does not present future project calls as part of EFSA’s work programme, or any future position of EFSA. It aims to support the development of a roadmap for action and its content can be subject to change. AboutPDF ToolsExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Volume19, Issue5May 2022E200505E RelatedInformation

Theme (concept) paper ‐ Risk Assessment of Combined Exposure to Multiple Chemicals (RACEMiC)

Abstract: EFSA Supporting PublicationsVolume 19, Issue 5 E200504E Technical reportOpen Access Theme (concept) paper - Risk Assessment of Combined Exposure to Multiple Chemicals (RACEMiC) European Food Safety Authority (EFSA), Corresponding Author European Food Safety Authority (EFSA) SPIDO@efsa.europa.eu Correspondence:SPIDO@efsa.europa.euSearch for more papers by this authorBruno Dujardin, Bruno DujardinSearch for more papers by this authorJulia Fabrega, Julia FabregaSearch for more papers by this authorJuliane Kleiner, Juliane KleinerSearch for more papers by this authorClaudia Heppner, Claudia HeppnerSearch for more papers by this authorMarta Hugas, Marta HugasSearch for more papers by this author European Food Safety Authority (EFSA), Corresponding Author European Food Safety Authority (EFSA) SPIDO@efsa.europa.eu Correspondence:SPIDO@efsa.europa.euSearch for more papers by this authorBruno Dujardin, Bruno DujardinSearch for more papers by this authorJulia Fabrega, Julia FabregaSearch for more papers by this authorJuliane Kleiner, Juliane KleinerSearch for more papers by this authorClaudia Heppner, Claudia HeppnerSearch for more papers by this authorMarta Hugas, Marta HugasSearch for more papers by this author First published: 31 May 2022 https://doi.org/10.2903/sp.efsa.2022.e200504 Amendment: : Authorship of this technical report was rearranged on the 27th of June 2022. Disclaimer: This document does not present future project calls as part of EFSA’s work programme, or any future position of EFSA. It aims to support the development of a roadmap for action and its content can be subject to change. AboutPDF ToolsExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Volume19, Issue5May 2022E200504E RelatedInformation

Environmental transformations of silver nanoparticles: impact on stability and toxicity.

Abstract: Silver nanoparticles (Ag-NPs) readily transform in the environment, which modifies their properties and alters their transport, fate, and toxicity. It is essential to consider such transformations when assessing the potential environmental impact of Ag-NPs. This review discusses the major transformation processes of Ag-NPs in various aqueous environments, particularly transformations of the metallic Ag cores caused by reactions with (in)organic ligands, and the effects of such transformations on physical and chemical stability and toxicity. Thermodynamic arguments are used to predict what forms of oxidized silver will predominate in various environmental scenarios. Silver binds strongly to sulfur (both organic and inorganic) in natural systems (fresh and sea waters) as well as in wastewater treatment plants, where most Ag-NPs are expected to be concentrated and then released. Sulfidation of Ag-NPs results in a significant decrease in their toxicity due to the lower solubility of silver sulfide, potentiall...

Functionalizing nanoparticles with biological molecules: developing chemistries that facilitate nanotechnology.

Abstract: Chemistries that Facilitate Nanotechnology Kim E. Sapsford,† W. Russ Algar, Lorenzo Berti, Kelly Boeneman Gemmill,‡ Brendan J. Casey,† Eunkeu Oh, Michael H. Stewart, and Igor L. Medintz*,‡ †Division of Biology, Department of Chemistry and Materials Science, Office of Science and Engineering Laboratories, U.S. Food and Drug Administration, Silver Spring, Maryland 20993, United States ‡Center for Bio/Molecular Science and Engineering Code 6900 and Division of Optical Sciences Code 5611, U.S. Naval Research Laboratory, Washington, D.C. 20375, United States College of Science, George Mason University, 4400 University Drive, Fairfax, Virginia 22030, United States Department of Biochemistry and Molecular Medicine, University of California, Davis, School of Medicine, Sacramento, California 95817, United States Sotera Defense Solutions, Crofton, Maryland 21114, United States

Toxicity of Ag, CuO and ZnO nanoparticles to selected environmentally relevant test organisms and mammalian cells in vitro: a critical review

Abstract: Nanoparticles (NPs) of copper oxide (CuO), zinc oxide (ZnO) and especially nanosilver are intentionally used to fight the undesirable growth of bacteria, fungi and algae. Release of these NPs from consumer and household products into waste streams and further into the environment may, however, pose threat to the ‘non-target’ organisms, such as natural microbes and aquatic organisms. This review summarizes the recent research on (eco)toxicity of silver (Ag), CuO and ZnO NPs. Organism-wise it focuses on key test species used for the analysis of ecotoxicological hazard. For comparison, the toxic effects of studied NPs toward mammalian cells in vitro were addressed. Altogether 317 L(E)C50 or minimal inhibitory concentrations (MIC) values were obtained for algae, crustaceans, fish, bacteria, yeast, nematodes, protozoa and mammalian cell lines. As a rule, crustaceans, algae and fish proved most sensitive to the studied NPs. The median L(E)C50 values of Ag NPs, CuO NPs and ZnO NPs (mg/L) were 0.01, 2.1 and 2.3 for crustaceans; 0.36, 2.8 and 0.08 for algae; and 1.36, 100 and 3.0 for fish, respectively. Surprisingly, the NPs were less toxic to bacteria than to aquatic organisms: the median MIC values for bacteria were 7.1, 200 and 500 mg/L for Ag, CuO and ZnO NPs, respectively. In comparison, the respective median L(E)C50 values for mammalian cells were 11.3, 25 and 43 mg/L. Thus, the toxic range of all the three metal-containing NPs to target- and non-target organisms overlaps, indicating that the leaching of biocidal NPs from consumer products should be addressed.

Mechanisms of Silver Nanoparticle Release, Transformation and Toxicity: A Critical Review of Current Knowledge and Recommendations for Future Studies and Applications.

Abstract: Nanosilver, due to its small particle size and enormous specific surface area, facilitates more rapid dissolution of ions than the equivalent bulk material; potentially leading to increased toxicity of nanosilver. This, coupled with their capacity to adsorb biomolecules and interact with biological receptors can mean that nanoparticles can reach sub-cellular locations leading to potentially higher localized concentrations of ions once those particles start to dissolve or degrade in situ. Further complicating the story is the capacity for nanoparticles to generate reactive oxygen species, and to interact with, and potentially disturb the functioning of biomolecules such as proteins, enzymes and DNA. The fact that the nanoparticle size, shape, surface coating and a host of other factors contribute to these interactions, and that the particles themselves are evolving or ageing leads to further complications in terms of elucidating mechanisms of interaction and modes of action for silver nanoparticles, in contrast to dissolved silver species. This review aims to provide a critical assessment of the current understanding of silver nanoparticle toxicity, as well as to provide a set of pointers and guidelines for experimental design of future studies to assess the environmental and biological impacts of silver nanoparticles. In particular; in future we require a detailed description of the nanoparticles; their synthesis route and stabilisation mechanisms; their coating; and evolution and ageing under the exposure conditions of the assay. This would allow for comparison of data from different particles; different environmental or biological systems; and structure-activity or structure-property relationships to emerge as the basis for predictive toxicology. On the basis of currently available data; such comparisons or predictions are difficult; as the characterisation and time-resolved data is not available; and a full understanding of silver nanoparticle dissolution and ageing under different conditions is observed. Clear concerns are emerging regarding the overuse of nanosilver and the potential for bacterial resistance to develop. A significant conclusion includes the need for a risk-benefit analysis for all applications and eventually restrictions of the uses where a clear benefit cannot be demonstrated.