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1.
Sci Data ; 11(1): 173, 2024 Feb 06.
Article in English | MEDLINE | ID: mdl-38321063

ABSTRACT

Predicting and elucidating the impacts of materials on human health and the environment is an unending task that has taken on special significance in the context of nanomaterials research over the last two decades. The properties of materials in environmental and physiological media are dynamic, reflecting the complex interactions between materials and these media. This dynamic behavior requires special consideration in the design of databases and data curation that allow for subsequent comparability and interrogation of the data from potentially diverse sources. We present two data processing methods that can be integrated into the experimental process to encourage pre-mediated interoperability of disparate material data: Knowledge Mapping and Instance Mapping. Originally developed as a framework for the NanoInformatics Knowledge Commons (NIKC) database, this architecture and associated methods can be used independently of the NIKC and applied across multiple subfields of nanotechnology and material science.

2.
Environ Sci Technol ; 57(44): 16728-16742, 2023 11 07.
Article in English | MEDLINE | ID: mdl-37898880

ABSTRACT

There is a long-standing appreciation among environmental engineers and scientists regarding the importance of biologically derived colloidal particles and their environmental fate. This interest has been recently renewed in considering bacteriophages and extracellular vesicles, which are each poised to offer engineers unique insights into fundamental aspects of environmental microbiology and novel approaches for engineering applications, including advances in wastewater treatment and sustainable agricultural practices. Challenges persist due to our limited understanding of interactions between these nanoscale particles with unique surface properties and their local environments. This review considers these biological particles through the lens of colloid science with attention given to their environmental impact and surface properties. We discuss methods developed for the study of inert (nonbiological) particle-particle interactions and the potential to use these to advance our understanding of the environmental fate and transport of extracellular vesicles and bacteriophages.


Subject(s)
Bacteriophages , Extracellular Vesicles , Environment , Colloids
3.
Environ Sci Technol ; 57(35): 13182-13192, 2023 09 05.
Article in English | MEDLINE | ID: mdl-37606695

ABSTRACT

Extracellular vesicles (EVs) are membrane-bounded, nanosized particles, produced and secreted by all biological cell types. EVs are ubiquitous in the environment, operating in various roles including intercellular communication and plant immune modulation. Despite their ubiquity, the role of EV surface chemistry in determining transport has been minimally investigated. Using the zeta (ζ)-potential as a surrogate for surface charge, this work considers the deposition of EVs from the yeast, Saccharomyces cerevisiae, and two bacterial species, Staphylococcus aureus and Pseudomonas fluorescens, in well-characterized porous medium under various background conditions shown to influence the transport of other environmental colloidal particles: ionic strength and humic acid concentration. The affinity of S. cerevisiae EVs for the porous medium (glass beads) appeared to be sensitive to changes in ionic strength, as predicted by colloid stability (Derjaguin, Landau, Verwey, and Overbeek or DLVO) theory, and humic acid concentration, while P. fluorescens EVs deviated from DLVO predictions, suggesting that mechanisms other than charge stabilization may control the deposition of P. fluorescens. Calculations of attachment efficiency from these deposition studies were used to estimate EV transport using a clean-bed filtration model. Based on these calculations, EVs could be transported through such homogeneous porous media up to 15 m.


Subject(s)
Extracellular Vesicles , Saccharomyces cerevisiae , Humic Substances , Porosity , Bacteria
4.
Colloids Surf B Biointerfaces ; 225: 113249, 2023 May.
Article in English | MEDLINE | ID: mdl-36905832

ABSTRACT

Extracellular vesicles (EVs) are nano-sized, biocolloidal proteoliposomes that have been shown to be produced by all cell types studied to date and are ubiquitous in the environment. Extensive literature on colloidal particles has demonstrated the implications of surface chemistry on transport behavior. Hence, one may anticipate that physicochemical properties of EVs, particularly surface charge-associated properties, may influence EV transport and specificity of interactions with surfaces. Here we compare the surface chemistry of EVs as expressed by zeta potential (calculated from electrophoretic mobility measurements). The zeta potentials of EVs produced by Pseudomonas fluorescens, Staphylococcus aureus, and Saccharomyces cerevisiae were largely unaffected by changes in ionic strength and electrolyte type, but were affected by changes in pH. The addition of humic acid altered the calculated zeta potential of the EVs, especially for those from S. cerevisiae. Differences in zeta potential were compared between EVs and their respective parent cell with no consistent trend emerging; however, significant differences were discovered between the different cell types and their EVs. These findings imply that, while EV surface charge (as estimated from zeta potential) is relatively insensitive to the evaluated environmental conditions, EVs from different organisms can differ regarding which conditions will cause colloidal instability.


Subject(s)
Extracellular Vesicles , Saccharomyces cerevisiae , Extracellular Vesicles/chemistry , Bacteria
5.
Microplast nanoplast ; 3(1): 6, 2023.
Article in English | MEDLINE | ID: mdl-36974201

ABSTRACT

A majority of American adults report having used sex toys, which, by design, interact with intimate and permeable body parts yet have not been subject to sufficient risk assessment or management. Physical and chemical data are presented examining potential risks associated with four types of currently available sex toys: anal toy, beads, dual vibrator, and external vibrator. A standardized abrasion machine made real-time breakdown of products into microplastics and nanoplastics. The microplastics from the sex toys were then solvent extracted and analyzed using GC-MS. Rates of microplastics and nanoplastics released during abrasion testing from most microplastic release to least was the anal toy, beads, dual vibrator, external vibrator. Both micro- and nanoplastics particles were generated following the abrasion test, with the 50 percentile diameters (D50) ranging from the anal beads at 658.5 µm, dual vibrator at 887.83 µm, anal toy at 950 µm, and external vibrator at 1673.33 µm. The material matrix of each product was analyzed using ATR-FTIR, with results identifying the anal toy as polyethylene terephthalate (PET), the anal beads as polyvinyl chloride (PVC), the external vibrator as a silicone blend (polydimethylsiloxane [PDMS]), and the dual vibrator as a rubber mixture (polyisoprene). After extraction, phthalates known to be endocrine disruptors were present in all tested sex toys at levels exceeding hazard warnings. Analogous findings have been reported for similar materials that, when incorporated into other product categories, are subject to regulatory scrutiny in both the US and EU. This data set is not intended to be representative of sex toys as an entire class of products, nor are the abrasion experiments claiming to simulate exact use conditions. However, these exploratory data frame potential concerns, highlighting research questions and the need for prompt prioritization of protective action. Therefore, future studies and multi-stakeholder action are needed to understand and reduce risk for this class of products. Supplementary Information: The online version contains supplementary material available at 10.1186/s43591-023-00054-6.

6.
Nat Nanotechnol ; 18(4): 412-418, 2023 04.
Article in English | MEDLINE | ID: mdl-36732591

ABSTRACT

Challenges in distinguishing between natural and engineered nanomaterials (ENMs) and the lack of historical records on ENM accidents have hampered attempts to estimate the accidental release and associated environmental impacts of ENMs. Building on knowledge from the nuclear power industry, we provide an assessment of the likelihood of accidental release rates of ENMs within the next 10 and 30 years. We evaluate risk predictive methodology and compare the results with empirical evidence, which enables us to propose modelling approaches to estimate accidental release risk probabilities. Results from two independent modelling approaches based on either assigning 0.5% of reported accidents to ENM-releasing accidents (M1) or based on an evaluation of expert opinions (M2) correlate well and predict severe accidental release of 7% (M1) in the next 10 years and of 10% and 20% for M2 and M1, respectively, in the next 30 years. We discuss the relevance of these results in a regulatory context.


Subject(s)
Environmental Pollutants , Nanostructures , Nanostructures/toxicity
8.
Environ Sci Technol ; 55(15): 10332-10342, 2021 08 03.
Article in English | MEDLINE | ID: mdl-34264058

ABSTRACT

Manufactured nanomaterials (MNMs) are incorporated as "nanofillers" into consumer products to enhance properties of interest. Multiwalled carbon nanotubes (MWCNTs) are known for their unique properties and have many applications in polymers. However, the release of MWCNTs during the nanoenabled product life cycle is concerning. During the use phase, mechanical stresses can produce fragmented materials containing MNMs. The degree of MNM release, the resulting exposure to these materials, and the potential impacts of their release are active research topics. In this study, we describe methodological improvements to study the abrasion of plastics containing MNMs (nanocomposites) and report on characteristics of abrasion products produced and rates of microplastic production. The abrasion device developed for this work allows for the measurement of power inputs to determine scaled release rates. Abrasion rates for plastics used in 3D printing were found to be 0.27 g/m2/s for the PETG polymer and 0.3 g/m2/s for the 2% MWCNT-PETG nanocomposite. Embedded and protuberant MWCNTs appeared to impact the particle size, shape, hydrophobicity, and surface charge of the microplastics, while the inclusion of MWCNTs had a small effect on microplastic production. Measurements of power input to the abrasion process provided a basis for estimating microplastic production rates for these nanocomposites.


Subject(s)
Nanocomposites , Nanotubes, Carbon , Microplastics , Plastics , Printing, Three-Dimensional
10.
Environ Sci Process Impacts ; 23(5): 664-677, 2021 May 26.
Article in English | MEDLINE | ID: mdl-33899070

ABSTRACT

All cells produce extracellular vesicles (EVs). These biological packages contain complex mixtures of molecular cargo and have a variety of functions, including interkingdom communication. Recent discoveries highlight the roles microbial EVs may play in the environment with respect to interactions with plants as well as nutrient cycling. These studies have also identified molecules present within EVs and associated with EV surfaces that contribute to these functions. In parallel, studies of engineered nanomaterials have developed methods to track and model small particle behavior in complex systems and measure the relative importance of various surface features on transport and function. While studies of EV behavior in complex environmental conditions have not yet employed transdisciplinary approaches, it is increasingly clear that expertise from disparate fields will be critical to understand the role of EVs in these systems. Here, we outline how the convergence of biology, soil geochemistry, and colloid science can both develop and address questions surrounding the basic principles governing EV-mediated interkingdom interactions.


Subject(s)
Extracellular Vesicles , Communication
11.
NanoImpact ; 23: 100331, 2021 07.
Article in English | MEDLINE | ID: mdl-35559832

ABSTRACT

The empirical necessity for integrating informatics throughout the experimental process has become a focal point of the nano-community as we work in parallel to converge efforts for making nano-data reproducible and accessible. The NanoInformatics Knowledge Commons (NIKC) Database was designed to capture the complex relationship between nanomaterials and their environments over time in the concept of an 'Instance'. Our Instance Organizational Structure (IOS) was built to record metadata on nanomaterial transformations in an organizational structure permitting readily accessible data for broader scientific inquiry. By transforming published and on-going data into the IOS we are able to tell the full transformational journey of a nanomaterial within its experimental life cycle. The IOS structure has prepared curated data to be fully analyzed to uncover relationships between observable phenomenon and medium or nanomaterial characteristics. Essential to building the NIKC database and associated applications was incorporating the researcher's needs into every level of development. We started by centering the research question, the query, and the necessary data needed to support the question and query. The process used to create nanoinformatic tools informs usability and analytical capability. In this paper we present the NIKC database, our developmental process, and its curated contents. We also present the Collaboration Tool which was built to foster building new collaboration teams. Through these efforts we aim to: 1) elucidate the general principles that determine nanomaterial behavior in the environment; 2) identify metadata necessary to predict exposure potential and bio-uptake; and 3) identify key characterization assays that predict outcomes of interest.


Subject(s)
Nanostructures , Databases, Factual , Metadata , Nanostructures/chemistry
12.
Nanotoxicology ; 15(10): 1403-1422, 2021 12.
Article in English | MEDLINE | ID: mdl-35166633

ABSTRACT

Polymer nanocomposites combine the versatile, lightweight characteristics of polymers with the properties of nanomaterials. Polyethylene terephthalate glycol (PETG) is commonly used in polymer additive manufacturing due to its controllable transparency, high modulus, and mechanical properties. Multi-walled carbon nanotubes (MWCNTs) add tensile strength, electrical conductivity, and thermal stability. The increased use of nanocomposites has led to concern over potential human health risks. We assessed morphologic alterations to determine impacts of ingested abraded nanocomposites compared to its component materials, pristine MWCNTs (1000 mg/L) and PETG. Adult transparent Japanese medaka (Oryzias latipes) were administered materials via oral gavage in 7 doses over 16 days. In vivo observations revealed altered livers and gallbladders following exposure to pristine MWCNTs and nanocomposites. Subsequent histologic sections showed fish exposed to pristine MWCNTs had highly altered biliary structures, and exposure to nanocomposites resulted in hepatocellular alteration. Thyroid follicle proliferation was also observed in fish exposed to materials containing MWCNTs. Transmission electron microscopy of livers showed that hepatocytes of fish exposed to MWCNTs had widespread swelling of rough endoplasmic reticulum, pronounced lysosomal activity, and swelling of intrahepatic biliary passageways. Fish exposed to nanocomposites had areas of degenerated hepatocytes with interspersed cellular debris. Each analysis showed that fish exposed to pristine PETG were most similar to controls. These results suggest that MWCNTs are the source of toxicity in abraded nanocomposite materials but that nanocomposites may also have some unique effects. The similarities of many teleost and mammalian tissues are such that these findings may indicate human health risks.


Subject(s)
Nanocomposites , Nanotubes, Carbon , Oryzias , Animals , Microscopy, Electron, Transmission , Nanocomposites/toxicity , Nanotubes, Carbon/chemistry , Nanotubes, Carbon/toxicity , Polymers
15.
Risk Anal ; 36(8): 1520-37, 2016 08.
Article in English | MEDLINE | ID: mdl-27510619

ABSTRACT

The Society for Risk Analysis (SRA) has a history of bringing thought leadership to topics of emerging risk. In September 2014, the SRA Emerging Nanoscale Materials Specialty Group convened an international workshop to examine the use of alternative testing strategies (ATS) for manufactured nanomaterials (NM) from a risk analysis perspective. Experts in NM environmental health and safety, human health, ecotoxicology, regulatory compliance, risk analysis, and ATS evaluated and discussed the state of the science for in vitro and other alternatives to traditional toxicology testing for NM. Based on this review, experts recommended immediate and near-term actions that would advance ATS use in NM risk assessment. Three focal areas-human health, ecological health, and exposure considerations-shaped deliberations about information needs, priorities, and the next steps required to increase confidence in and use of ATS in NM risk assessment. The deliberations revealed that ATS are now being used for screening, and that, in the near term, ATS could be developed for use in read-across or categorization decision making within certain regulatory frameworks. Participants recognized that leadership is required from within the scientific community to address basic challenges, including standardizing materials, protocols, techniques and reporting, and designing experiments relevant to real-world conditions, as well as coordination and sharing of large-scale collaborations and data. Experts agreed that it will be critical to include experimental parameters that can support the development of adverse outcome pathways. Numerous other insightful ideas for investment in ATS emerged throughout the discussions and are further highlighted in this article.


Subject(s)
Ecotoxicology , Environmental Health , Nanostructures/chemistry , Nanotechnology/legislation & jurisprudence , Humans , Risk Assessment , Safety
16.
Nanoscale ; 8(19): 9919-43, 2016 May 21.
Article in English | MEDLINE | ID: mdl-27143028

ABSTRACT

Nanotechnology is of increasing significance. Curation of nanomaterial data into electronic databases offers opportunities to better understand and predict nanomaterials' behaviour. This supports innovation in, and regulation of, nanotechnology. It is commonly understood that curated data need to be sufficiently complete and of sufficient quality to serve their intended purpose. However, assessing data completeness and quality is non-trivial in general and is arguably especially difficult in the nanoscience area, given its highly multidisciplinary nature. The current article, part of the Nanomaterial Data Curation Initiative series, addresses how to assess the completeness and quality of (curated) nanomaterial data. In order to address this key challenge, a variety of related issues are discussed: the meaning and importance of data completeness and quality, existing approaches to their assessment and the key challenges associated with evaluating the completeness and quality of curated nanomaterial data. Considerations which are specific to the nanoscience area and lessons which can be learned from other relevant scientific disciplines are considered. Hence, the scope of this discussion ranges from physicochemical characterisation requirements for nanomaterials and interference of nanomaterials with nanotoxicology assays to broader issues such as minimum information checklists, toxicology data quality schemes and computational approaches that facilitate evaluation of the completeness and quality of (curated) data. This discussion is informed by a literature review and a survey of key nanomaterial data curation stakeholders. Finally, drawing upon this discussion, recommendations are presented concerning the central question: how should the completeness and quality of curated nanomaterial data be evaluated?

17.
Beilstein J Nanotechnol ; 6: 1752-62, 2015.
Article in English | MEDLINE | ID: mdl-26425427

ABSTRACT

The Nanomaterial Data Curation Initiative (NDCI), a project of the National Cancer Informatics Program Nanotechnology Working Group (NCIP NanoWG), explores the critical aspect of data curation within the development of informatics approaches to understanding nanomaterial behavior. Data repositories and tools for integrating and interrogating complex nanomaterial datasets are gaining widespread interest, with multiple projects now appearing in the US and the EU. Even in these early stages of development, a single common aspect shared across all nanoinformatics resources is that data must be curated into them. Through exploration of sub-topics related to all activities necessary to enable, execute, and improve the curation process, the NDCI will provide a substantive analysis of nanomaterial data curation itself, as well as a platform for multiple other important discussions to advance the field of nanoinformatics. This article outlines the NDCI project and lays the foundation for a series of papers on nanomaterial data curation. The NDCI purpose is to: 1) present and evaluate the current state of nanomaterial data curation across the field on multiple specific data curation topics, 2) propose ways to leverage and advance progress for both individual efforts and the nanomaterial data community as a whole, and 3) provide opportunities for similar publication series on the details of the interactive needs and workflows of data customers, data creators, and data analysts. Initial responses from stakeholder liaisons throughout the nanoinformatics community reveal a shared view that it will be critical to focus on integration of datasets with specific orientation toward the purposes for which the individual resources were created, as well as the purpose for integrating multiple resources. Early acknowledgement and undertaking of complex topics such as uncertainty, reproducibility, and interoperability is proposed as an important path to addressing key challenges within the nanomaterial community, such as reducing collateral negative impacts and decreasing the time from development to market for this new class of technologies.

18.
Sci Total Environ ; 536: 1029-1037, 2015 Dec 01.
Article in English | MEDLINE | ID: mdl-26188653

ABSTRACT

The study of nanomaterial impacts on environment, health and safety (nanoEHS) has been largely predicated on the assumption that exposure and hazard can be predicted from physical-chemical properties of nanomaterials. This approach is rooted in the view that nanoöbjects essentially resemble chemicals with additional particle-based attributes that must be included among their intrinsic physical-chemical descriptors. With the exception of the trivial case of nanomaterials made from toxic or highly reactive materials, this approach has yielded few actionable guidelines for predicting nanomaterial risk. This article addresses inherent problems in structuring a nanoEHS research strategy based on the goal of predicting outcomes directly from nanomaterial properties, and proposes a framework for organizing data and designing integrated experiments based on functional assays (FAs). FAs are intermediary, semi-empirical measures of processes or functions within a specified system that bridge the gap between nanomaterial properties and potential outcomes in complex systems. The three components of a functional assay are standardized protocols for parameter determination and reporting, a theoretical context for parameter application and reference systems. We propose the identification and adoption of reference systems where FAs may be applied to provide parameter estimates for environmental fate and effects models, as well as benchmarks for comparing the results of FAs and experiments conducted in more complex and varied systems. Surface affinity and dissolution rate are identified as two critical FAs for characterizing nanomaterial behavior in a variety of important systems. The use of these FAs to predict bioaccumulation and toxicity for initial and aged nanomaterials is illustrated for the case of silver nanoparticles and Caenorhabditis elegans.


Subject(s)
Biological Assay/methods , Environmental Monitoring/methods , Environmental Pollutants/toxicity , Nanostructures/toxicity , Risk Assessment
19.
ACS Nano ; 9(4): 3409-17, 2015.
Article in English | MEDLINE | ID: mdl-25791861

ABSTRACT

For nanotechnology to meet its potential as a game-changing and sustainable technology, it is important to ensure that the engineered nanomaterials and nanoenabled products that gain entry to the marketplace are safe and effective. Tools and methods are needed for regulatory purposes to allow rapid material categorization according to human health and environmental risk potential, so that materials of high concern can be targeted for additional scrutiny, while material categories that pose the least risk can receive expedited review. Using carbon nanotubes as an example, we discuss how data from alternative testing strategies can be used to facilitate engineered nanomaterial categorization according to risk potential and how such an approach could facilitate regulatory decision-making in the future.


Subject(s)
Decision Making , Government Regulation , Nanotechnology/legislation & jurisprudence , Animals , Engineering , Humans , Nanotubes, Carbon/toxicity , Risk Assessment , Safety , Toxicity Tests , United States , United States Environmental Protection Agency/legislation & jurisprudence
20.
Sci Total Environ ; 470-471: 660-8, 2014 Feb 01.
Article in English | MEDLINE | ID: mdl-24176714

ABSTRACT

Prioritizing and assessing risks associated with chemicals, industrial materials, or emerging technologies is a complex problem that benefits from the involvement of multiple stakeholder groups. For example, in the case of engineered nanomaterials (ENMs), scientific uncertainties exist that hamper environmental, health, and safety (EHS) assessments. Therefore, alternative approaches to standard EHS assessment methods have gained increased attention. The objective of this paper is to describe the application of a web-based, interactive decision support tool developed by the U.S. Environmental Protection Agency (U.S. EPA) in a pilot study on ENMs. The piloted tool implements U.S. EPA's comprehensive environmental assessment (CEA) approach to prioritize research gaps. When pursued, such research priorities can result in data that subsequently improve the scientific robustness of risk assessments and inform future risk management decisions. Pilot results suggest that the tool was useful in facilitating multi-stakeholder prioritization of research gaps. Results also provide potential improvements for subsequent applications. The outcomes of future CEAWeb applications with larger stakeholder groups may inform the development of funding opportunities for emerging materials across the scientific community (e.g., National Science Foundation Science to Achieve Results [STAR] grants, National Institutes of Health Requests for Proposals).


Subject(s)
Environmental Policy , Environmental Pollution/prevention & control , Internet , Risk Management/methods , Environmental Exposure , Environmental Pollution/analysis , Environmental Pollution/statistics & numerical data , Information Dissemination , Risk Assessment , United States , United States Environmental Protection Agency
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