Harald Krug

Harald Krug
NanoCASE GmbH

PhD

About

226
Publications
35,562
Reads
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9,967
Citations
Introduction
Harald Krug has retired from his position within the General Management, Empa - Swiss Federal Laboratories for Materials Science and Technology and is Emeritus from the University of Berne since October 2017. Harald has founded an own company www.NanoCASE.ch for consulting in nanosafety and focusses on products with nanomaterials. One current project is 'DaNa4.0 www.nanoobjects.info.'
Additional affiliations
March 2014 - present
NanoCASE GmbH
Position
  • Consultant
Description
  • Expert in Nanotoxicology and Nanosafety Aspects.
January 2010 - May 2014
Empa - Swiss Federal Laboratories for Materials Science and Technology
Position
  • Member of the Board of Directors
Description
  • Expert in Nanotoxicology and Nanosafety Aspects Toxicology of Metal Compounds
January 2007 - September 2017
Empa - Swiss Federal Laboratories for Materials Science and Technology
Position
  • Managing Director
Description
  • Expert in Nanotoxicology and Nanosfety Aspects New Biological Models 3D Cell Culture Models Metal Toxicology
Education
April 1978 - May 1982
Georg-August-Universität Göttingen
Field of study
  • Physiological regulation of circadian rhythms

Publications

Publications (226)
Article
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Background Nanomaterials are suspected of causing health problems, as published studies on nanotoxicology indicate. On the other hand, some of these materials, such as nanostructured pyrogenic and precipitated synthetic amorphous silica (SAS) and silica gel, have been used for decades without safety concerns in industrial, commercial, and consumer...
Article
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Hazard assessment is the first step in nanomaterial risk assessment. The overall number of studies on the biological effects of nanomaterials or innovative materials is steadily increasing and is above 40,000. Several databases have been established to make the amount of data manageable, but these are often highly specialized or can be used only by...
Article
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Faster, cheaper, sensitive, and mechanisms-based animal alternatives are needed to address the safety assessment needs of the growing number of nanomaterials (NM) and their sophisticated property variants. Specifically, strategies that help identify and prioritize alternative schemes involving individual test models, toxicity endpoints, and assays...
Article
Significant advances have been made in the development of Adverse Outcome Pathways (AOPs) over the last decade, mainly focused on the toxicity mechanisms of chemicals. These AOPs, although relevant to manufactured nanomaterials (MNs), do not currently capture the reported roles of size-associated properties of MNs on toxicity. Moreover, some AOs of...
Article
One of the challenges in using in vitro data to understand the potential risks of engineered nanomaterials (ENMs) is that results often differ or are even contradictory among studies. While it is recognized that numerous factors can influence results produced by nanobioassays, there has not yet been a consistently used conceptual framework to ident...
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Adverse outcome pathways (AOPs) represent a sequence of key events (KEs) between a molecular initiating event (MIE) and an adverse outcome (AO) and span many levels of biological organization including molecular, cellular, tissue, organ, organism, and population. AOPs link specific biological observations with AOs. AOPs are not specific to individu...
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For this Editorial, we, the guest editors, performed a brief review with the aim of setting the framework for the Special issue on the “Environmental Impacts of Nanomaterials” [...]
Article
Use and production of chemicals and new materials are always reasons for concern especially with regard to human health and the environmental impacts. Over the past few decades occupational safety is a greater focus for toxicologists and of national and international registration programs for new products. Thus, the careful investigation of the bio...
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Nanotechnology is closely related to the tailored manufacturing of nanomaterials for a huge variety of applications. However, such applications with newly developed materials are also a reason for concern. The DaNa2.0 project provides information and support for these issues on the web in condensed and easy-to-understand wording. Thus, a key challe...
Article
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Green Toxicology refers to the application of predictive toxicology in the sustainable development and production of new less harmful materials and chemicals, subsequently reducing waste and exposure. Built upon the foundation of “Green Chemistry” and “Green Engineering”, “Green Toxicology” aims to shape future manufacturing processes and safe synt...
Article
After 15 years of intense research on the risks of nanomaterials, the evaluation of specific nanomaterials is still difficult. The more research is performed, the more studies which demonstrate critical effects of nanomaterials are published. In this regard, it should be noted that most published studies do not show usable toxicological results, al...
Article
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Background Understanding the interaction of graphene-related materials (GRM) with human cells is a key to the assessment of their potential risks for human health. There is a knowledge gap regarding the potential uptake of GRM by human intestinal cells after unintended ingestion. Therefore the aim of our study was to investigate the interaction of...
Article
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The design and use of materials in the nanoscale size range for addressing medical and health-related issues continues to receive increasing interest. Research in nanomedicine spans a multitude of areas, including drug delivery, vaccine development, diagnosis and imaging tools, wearable devices, high-throughput screening platforms, etc. using biolo...
Article
The OECD created the Working Party on Manufactured Nanomaterials (WPMN), which launched the Testing Programme of Manufactured Nanomaterials in 2007 in order to test the applicability of the test guidelines established for chemicals on nanoparticles. After several years of testing, 11 dossiers were made publicly available in 2015. A first analysis o...
Article
Sowohl Wissenschaftler als auch der Bürger brauchen verlässliche Informationen, wenn sie faktenorientiert über die Sicherheit von Nanomaterialien diskutieren wollen. Nicht alle Artikel zu diesem Thema eignen sich für eine Risikoabschätzung. Deshalb ist es notwendig, geeignete von ungeeigneten Artikeln zu trennen. Dies ist das Ziel des vom Bundesmin...
Article
The success of nanotechnology is particularly based on its versatility. It will bring about fundamental changes of basic research as well as of many sectors of industry. It will also have a great impact on our daily life ranging from electronics to the health care system. However, consumers and students often miss reliable and understandable inform...
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The use of nanotechnology and advanced materials promises to revolutionise many areas of technology and improve our daily life. In that respect, many positive effects on the environment are expected, either directly, by developing new technologies for remediation, filtering techniques or energy generation, or indirectly, by e.g. saving resources du...
Article
Full-text available
After 15 years of intense research on the risks of nanomaterials, the evaluation of specific nanomaterials is still difficult. The more research is performed, the more studies which demonstrate critical effects of nanomaterials are published. In this regard, it should be noted that most published studies do not show usable toxicological results, al...
Article
Full-text available
Models of the outer epithelia of the human body - namely the skin, the intestine and the lung - have found valid applications in both research and industrial settings as attractive alternatives to animal testing. A variety of approaches to model these barriers are currently employed in such fields, ranging from the utilization of ex vivo tissue to...
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Nanotechnology is a rapidly expanding and highly promising new technology with many different fields of application. Consequently, the investigation of engineered nanoparticles in biological systems is steadily increasing. Questions about the safety of such engineered nanoparticles are very important and the most critical subject with regard to the...
Article
Perovskites: Is there a reason for concern? - Volume 40 Issue 8 - Prachi Patel, Harald F. Krug
Article
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Nanoparticle exposure in utero might not be a major concern yet, but could become more important with the increasing application of nanomaterials in consumer and medical products. Several epidemiologic and in vitro studies have shown that nanoparticles can have potential toxic effects. However, nanoparticles also offer the opportunity to develop ne...
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An important consideration in developing standards and regulations that govern the production and use of commercial nanoscale materials is the development of robust and reliable measurements to monitor the potential adverse biological effects of such products. These measurements typically require cell-based and other biological assays that provide...
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Major accident regulations aim at protecting the population and the environment from possible accidental releases of chemicals. To achieve this goal, the regulations need to be reassessed in light of the development of new technologies. A currently rapidly growing new technology is nanotechnology, and engineered nanomaterials (ENM) are already prod...
Article
Die Zahl der publizierten Studien zum Thema Nanosicherheit spricht für sich. Wir verzeichnen seit ungefähr 15 Jahren einen nahezu exponentiellen Anstieg bei den Publikationen zur “Nanotoxikologie”. Waren es bis zum Jahr 2000 noch wenige Hundert, so sind seit 2001 mehr als 10 000 Publikationen zum Thema “Nanomaterialien: Umwelt und Gesundheit” veröf...
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The number of studies that have been published on the topic of nanosafety speaks for itself. We have seen an almost exponential rise over the past 15 years or so in the number of articles on nanotoxicology. Although only a couple of hundred papers had appeared on the topic of "Nanomaterials: environmental and health effects" before 2000, this numbe...
Article
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Background Assessing the impact of new technologies or newly developed substances on our environment is a challenge, even more so if the applied test methods - both toxicological and analytical - are often found to be inadequate and need amendments or even new developments as it is in the case of nanotechnology. This is illustrated by numerous publ...
Article
Graphing graphene: Because the naming of graphene-based materials (GBMs) has led to confusion and inconsistency, a classification approach is necessary. Three physical-chemical properties of GBMs have been defined by the GRAPHENE Flagship Project of the European Union for the unequivocal classification of these materials (see grid).
Article
Ein Graph für Graphene: Die Erwartungen bezüglich der Anwendungsmöglichkeiten von Graphen sind enorm. Ein klares System zur Bezeichnung von Graphenderivaten fördert eine präzise Fachsprache für die Familie der graphenbasierten Materialien. Im Rahmen des GRAPHEN-Flagship-Projekts der EU wurden drei physikalisch-chemische Eigenschaften von Graphen de...
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In January 2014, the Swiss Federal Laboratories for Materials Science and Technology (Empa) joined the National Institute for Materials Science (NIMS) in collaborative activities on Science and Technology of Advanced Materials (STAM). STAM was founded in 2000. In 2005 NIMS took over the management of its peer review and financial systems, resulting...
Article
Our expanding ability to handle the "literally invisible" building blocks of our world has started to provoke a seismic shift on the technology, environment and health sectorsin our society. During the last two decades, it has become increasingly evident that the "nano-sized" subunits composing many materials - living, natural and synthetic - are b...
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The release of reactive oxygen species (ROS) during the electron transport of mitochondrial aerobic respiration is the major source of ROS. However, contact between cells and nanoparticles (NPs) can also induce release of ROS, leading to an imbalance towards the pro-oxidative state. At low levels of ROS production, cells initiate a protective respo...
Article
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A comprehensive in vitro assessment of two commercial metal oxide nanoparticles, TiO2 and ZnO, was performed using human monocyte-derived macrophages (HMDM), monocyte-derived dendritic cells (MDDC), and Jurkat T cell leukemia-derived cell line. TiO2 nanoparticles were found to be non-toxic whereas ZnO nanoparticles caused dose-dependent cell death....
Data
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XRD pattern of ZnO nanoparticles. XRD spectra for ZnO-5, ZnO-6, ZnO-7, ZnO-8 and ZnO-9. They all reveal the typical peaks of hexagonal wurtzite type crystal structure. XRD results for ZnO-1, ZnO-2, ZnO-3, ZnO-4 and TiO2 have been presented in Buerki-Thurnherr et al. [7]. (PDF)
Data
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Expression of the metallothioneins validated with RT-PCR in response to ZnO-1 and TiO2 nanoparticles. Figure shows the normalized log2-transformed average expression levels in untreated control MDDC, HMDM and Jurkat cells and the expression after exposure of the cells with 10 µg/ml of ZnO-1 or 10 µg/ml of TiO2 at 6 and 24 h of culture. The data is...
Data
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Hierarchical clustering of the expression of the ZnO responsive genes reported by Moos et al. [10] among A) HMDM samples and B) Jurkat samples in Illumina Sentrix HumanHT-12 Expression BeadChip data after exposing the cells with 1 µg/ml or 10 µg/ml of ZnO-1 or TiO2 for 6 or 24 h in three replicate experiments (see Figure S4 and Table S3). The subcl...
Data
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Donor or replicate culture -specific responses to ZnO-1. Venn diagrams of the differentially expressed genes in MDDC, HMDM and Jurkat cells (FC>1.5 or <−1.5) in each donor or replicate experiment at 6 h and 24 h timepoints after exposure to 10 µg/ml of ZnO-1 compared to the corresponding untreated control cells analyzed with Illumina Sentrix HumanH...
Data
Hierarchical clustering of the samples analyzed with Affymetrix GeneChip Human Genome U219 array plates. The data is from three replicate experiments of Jurkat cells exposed with 10 µg/ml of ZnO-2, ZnO-3, ZnO-5 or ZnO-9 for 24 h; or 10 µg/ml, 25 µg/ml, 50 µg/ml or 100 µg/ml of ZnO-4 for 24 h; HMDM, MDDC or Jurkat cells exposed with 10 µg/ml of ZnO-...
Data
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Size distribution charts of the ENs. Transmission electron microscopy (TEM) was used to investigate the size of the ENs. Hundred particles were counted for each sample. Size distribution charts presented show the particle size frequencies, an average diameter and a calculated statistical standard deviation acquired with non-linear fitting of the da...
Data
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ZnO-1 response in MDDCs. A) Hierarchical clustering of the ZnO-1 (10 µg/ml) treated, or the untreated control MDDC samples using correlation distance and complete linkage in clustering. Seven different donors were used in the analysis. The gene expressions were measured with Affymetrix GeneChip Human Genome U219 array plates. The samples from the d...
Data
Physicochemical characterization of the nanoparticles. (XLSX)
Data
The differentially expressed genes in the Illumina study. (XLSX)
Data
Normalized expression of SLC30A and SLC39A family members. (XLSX)
Data
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TEM analysis of ZnO nanoparticles. TEM micrographs of A) ZnO-1, B) ZnO-2, C) ZnO-3, D) ZnO-4, E) ZnO-5, F) ZnO-6, G) ZnO-7, H) ZnO-8, I) ZnO-9 and J) TiO2. (PDF)
Data
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Schematic presentation of the experimental set-up for Illumina microarray hybridizations. HMDM samples are used as an example in the figure. Similar experiments were performed with MDDC and Jurkat cells. The red dotted arrows indicate the basic comparisons done for the microarray data. All experiments were repeated three times with independent cell...
Data
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MTT analysis of HMDM. Toxicity of ZnO-1 and TiO2 ENs were assessed with MTT assay. ZnO-1 caused dose-dependent loss of cell viability whereas TiO2 was inert. The figure shows an average and the standard deviation of three independent cultures. Similar trends in toxicity were obtained using MDDC [23] and the Jurkat cells [7]. The cell viability of H...
Data
Overlap of our findings with Moos et al. 2011 dataset. (XLSX)
Data
Full-text available
ZnO-1 and TiO2 induced gene expression in HMDM, MDDC and Jurkat cells. The number of genes having on average at least 1.5-fold difference in expression between the nanoparticle exposed and the untreated control cells in the whole-genome microarray analysis with Illumina Sentrix HumanHT-12 Expression BeadChips. The cell type, timepoint and the doses...
Data
Schematic presentation of the experimental set-up for Affymetrix GeneChip Human Genome U219 array hybridizations. MDDC samples from four donors treated for 24 h with 10 µg/ml of ZnO-1 or cultured without exposure were hybridized to Affymetrix arrays. At the same time ZnO-1 (10 µg/ml) or untreated control cells cultured for 6 or 24 h from three repl...
Data
XRD, TGA and FT-IR analysis of the ZnO ENs. (XLSX)
Data
The differentially expressed genes in the Affymetrix study. (XLSX)
Data
Overlap of our findings with Cousins et al. 2003 dataset. (XLS)
Data
Full-text available
Hierarchical clustering of the expression of the zinc responsive genes reported by Cousins et al. [28] among A) HMDM samples and B) Jurkat samples in Illumina Sentrix HumanHT-12 Expression BeadChip data after exposing the cells with 1 µg/ml or 10 µg/ml of ZnO-1 or TiO2 for 6 or 24 h in three replicate experiments (see Figure S4 and Table S3). The s...
Data
The samples used in the study. (XLSX)
Data
Supplementary methods containing nanoparticle production and characterization, and cell viability analysis methods. (DOCX)
Article
Full-text available
Decades ago the human placenta was thought to be an impenetrable barrier between mother and unborn child. However, the discovery of thalidomide-induced birth defects and many later studies afterwards proved the opposite. Today several harmful xenobiotics like nicotine, heroin, methadone or drugs as well as environmental pollutants were described to...
Article
It is expected that ceramic nanoparticles will be more intensely used in various technical, medical and biological fields in the near future. But their interaction with biological objects has not yet been completely understood. Within the scientific community, NGOs and the public, there is considerable concern about possible side-effects on health...
Article
Full-text available
Nanotechnology is considered one of the key technologies of the 21st century. The success of this fascinating technology is based on its versatility. It will bring about fundamental changes of basic research as well as of many sectors of industry and also of daily life from electronics to the health care system. However, consumers often miss reliab...
Article
Full-text available
Background Increasing concern has been expressed regarding the potential adverse health effects that may be associated with human exposure to inhaled multi-walled carbon nanotubes (MWCNTs). Thus it is imperative that an understanding as to the underlying mechanisms and the identification of the key factors involved in adverse effects are gained. In...