RSC Environmental Science desktop seminars
The Royal Society of Chemistry’s suite of Environmental Science journals has initiated a new series of desktop seminars. At a time when travel and physical meetings are off most people’s agendas, they represent a welcome opportunity to share new knowledge and achieve some continuous professional development in a forum available to a wide audience: the opportunity was seized by attendees from over 50 countries.
The Environmental Science journal series has four members: Environmental Science: Nano, Environmental Science: Water, Environmental Science: Atmospheres, and Environmental Science: Processes and Impacts. The journals aim for timely publication of new research through fast turnaround from submission to publication. The desktop seminars reflected the four interest areas.
The series was opened by Professor Peter Vikesland, Professor of Civil and Environmental Engineering at Virginia Tech, USA, and co-director of the Virginia Tech Sustainable Nanotechnology Center (VTSuN). He is also editor-in-chief of Environmental Science: Nano. His talk focussed on the implications and applications of nanotechnology for the environment. Professor Vikesland started with a historical perspective on the implications and applications of nanotechnology over the last 15+ years.
The lecture outlined a number of case studies, the first of which described how work to understand the toxicity of C60 fullerenes led to the finding that toxicity was significantly reduced when the bucky balls were hydroxylated. This difference in toxicity was attributed to differences in the production of reactive oxygen species. This understanding led in turn led to the development of antiviral and antibacterial applications. Another example was the development of nanocellulose as a sensor platform. Feeding organic precursors such as fructose to certain bacteria creates bacterial cellulose. This nanocellulose can be mixed with guest nanomaterials, such as gold nanoparticles, to create nanocomposites with useful properties (e.g. availability as a hydrogel, and being reversibly adherent). The nanocomposites are used to enable reversible pollutant detection by Surface Enhanced Raman Spectroscopy and to produce photothermally active membranes for water treatment.
Professor Vikesland ended by proposing a single cycle perspective of applications and implications of nanotechnology in the green nanotechnology sustainability arena.
The second seminar in the series, “How virus structure and chemistry impacts environmental fate”, was presented by Dr Krista Wiggington, Associate Professor of Environmental Engineering at the University of Michigan and Environmental Science: Water Research and Technology Associate Editor. Professor Wiggington described how virus models with different characteristics are used to understand virus fate in the environment and develop new detection methods. She provided an overview of virus characteristics: they are small (eg 23-40 nm for norovirus and so too small for filtration), have different types of genomes (double or single stranded, DNA or RNA), and are non-enveloped (with a genome surrounded by just a protein capsid) or enveloped (with an additional lipid bilayer). Professor Wiggington revealed that a model enveloped virus “Phi6”, was more susceptible to free chlorine inactivation than a model non-enveloped virus, “MS2”. The inactivation mechanism of the enveloped virus with free chlorine in Phi6 was likely protein-mediated, while that of MS2 was likely genome-mediated. Professor Wiggington examined the partitioning of model enveloped viruses in untreated wastewater compared with non-enveloped viruses, and found that the former partitioned to a greater extent with wastewater solids than non-enveloped viruses.
Finally, Professor Wiggington described work to develop models for deactivation rates of single-strand RNA viruses and double-strand DNA viruses under UV254 light. The model was able to predict the experimentally observed rate for an untested subject virus within 5% and showed coronaviruses to be highly susceptible to UV254 – more than double the next most susceptible single-strand RNA virus.
The Environmental Science journal series has four members: Environmental Science: Nano, Environmental Science: Water, Environmental Science: Atmospheres, and Environmental Science: Processes and Impacts. The journals aim for timely publication of new research through fast turnaround from submission to publication. The desktop seminars reflected the four interest areas.
The series was opened by Professor Peter Vikesland, Professor of Civil and Environmental Engineering at Virginia Tech, USA, and co-director of the Virginia Tech Sustainable Nanotechnology Center (VTSuN). He is also editor-in-chief of Environmental Science: Nano. His talk focussed on the implications and applications of nanotechnology for the environment. Professor Vikesland started with a historical perspective on the implications and applications of nanotechnology over the last 15+ years.
The lecture outlined a number of case studies, the first of which described how work to understand the toxicity of C60 fullerenes led to the finding that toxicity was significantly reduced when the bucky balls were hydroxylated. This difference in toxicity was attributed to differences in the production of reactive oxygen species. This understanding led in turn led to the development of antiviral and antibacterial applications. Another example was the development of nanocellulose as a sensor platform. Feeding organic precursors such as fructose to certain bacteria creates bacterial cellulose. This nanocellulose can be mixed with guest nanomaterials, such as gold nanoparticles, to create nanocomposites with useful properties (e.g. availability as a hydrogel, and being reversibly adherent). The nanocomposites are used to enable reversible pollutant detection by Surface Enhanced Raman Spectroscopy and to produce photothermally active membranes for water treatment.
Professor Vikesland ended by proposing a single cycle perspective of applications and implications of nanotechnology in the green nanotechnology sustainability arena.
The second seminar in the series, “How virus structure and chemistry impacts environmental fate”, was presented by Dr Krista Wiggington, Associate Professor of Environmental Engineering at the University of Michigan and Environmental Science: Water Research and Technology Associate Editor. Professor Wiggington described how virus models with different characteristics are used to understand virus fate in the environment and develop new detection methods. She provided an overview of virus characteristics: they are small (eg 23-40 nm for norovirus and so too small for filtration), have different types of genomes (double or single stranded, DNA or RNA), and are non-enveloped (with a genome surrounded by just a protein capsid) or enveloped (with an additional lipid bilayer). Professor Wiggington revealed that a model enveloped virus “Phi6”, was more susceptible to free chlorine inactivation than a model non-enveloped virus, “MS2”. The inactivation mechanism of the enveloped virus with free chlorine in Phi6 was likely protein-mediated, while that of MS2 was likely genome-mediated. Professor Wiggington examined the partitioning of model enveloped viruses in untreated wastewater compared with non-enveloped viruses, and found that the former partitioned to a greater extent with wastewater solids than non-enveloped viruses.
Finally, Professor Wiggington described work to develop models for deactivation rates of single-strand RNA viruses and double-strand DNA viruses under UV254 light. The model was able to predict the experimentally observed rate for an untested subject virus within 5% and showed coronaviruses to be highly susceptible to UV254 – more than double the next most susceptible single-strand RNA virus.
The third talk was from Carnegie Mellon University’s Professor Neil Donahue on his collaborative work using the proton synchrotron at CERN to study the chemistry and physics of the atmosphere. The work, presented from the CLOUD consortium (https://home.cern/science/experiments/cloud), was motivated by an interest in the cooling effects that particles such as sulfur and clouds have on the Earth’s climate, i.e. in opposition to greenhouse gases like CO2. The impact of this cooling effect is more uncertain than warming. Professor Donahue’s work explored the atmospherically-relevant chemistry and physics behind particle growth and composition. A particularly exciting example was the well-studied particle formation system of SO2 and NH3. Professor Donahue used the CLOUD chamber to observe how this process shows a stepwise increase in particle formation rate when other species (NO2, HNO3) are present, providing insights into particle formation routes in wintertime pollution events in cities (such as Beijing) and the importance of nitrate in contributing to health-threatening particle concentrations.
This seminar was sponsored by the RSC’s new open-access Environmental Science: Atmospheres. Attendees were given an overview of the new journal and its transparent format, including options to concurrently publish peer-reviews alongside the accepted manuscript.
The final lecture was given by Professor Delphine Farmer. Her talk, “Masters of their fate: Revisiting atmospheric particle deposition and lifetime”, was sponsored by Environmental Science: Processes and Impacts. It examined how particles in the atmosphere interact with and are taken up by different topographical surfaces such as forests and grassland, as well as how those processes impact on atmospheric longevity, and consequently on climate and air quality. The means by which particles are removed from the atmosphere are via wet and dry deposition and Professor Farmer described her work looking at dry deposition.
Particles in the air are the strongest contributors to uncertainty in radiative forcing estimates, that is, the difference between sunlight energy absorbed by the earth and energy radiated back into space. Dry deposition is the strongest individual source of uncertainty. Professor Farmer described particle dry deposition as being made up of four main processes: gravity, impaction, and interception (being carried round and attaching to surfaces) for larger particles, and Brownian diffusion for smaller sub-micron particles. Size of particles drives atmospheric longevity. The lifetime of smaller particles exceeds that of larger particles. Studies by her team have shown that dry deposition influences the lifetime of particles, and that widely used parameterisations poorly capture the size-dependence of observations. Current models overestimate cooling effects over land from direct radiative effects and substantially underestimate indirect cooling effects. She recommended model revision.
Summary
This desktop series provided an opportunity for the RSC to showcase its relatively new series of Environmental Science journals, researchers to publicise their work to a wide audience, whilst the range of themes examined in the presentations and the short, on-line format has enabled very many attendees to deepen their understanding, or investigate a new area of knowledge. It has been a welcome initiative.
References
The final lecture was given by Professor Delphine Farmer. Her talk, “Masters of their fate: Revisiting atmospheric particle deposition and lifetime”, was sponsored by Environmental Science: Processes and Impacts. It examined how particles in the atmosphere interact with and are taken up by different topographical surfaces such as forests and grassland, as well as how those processes impact on atmospheric longevity, and consequently on climate and air quality. The means by which particles are removed from the atmosphere are via wet and dry deposition and Professor Farmer described her work looking at dry deposition.
Particles in the air are the strongest contributors to uncertainty in radiative forcing estimates, that is, the difference between sunlight energy absorbed by the earth and energy radiated back into space. Dry deposition is the strongest individual source of uncertainty. Professor Farmer described particle dry deposition as being made up of four main processes: gravity, impaction, and interception (being carried round and attaching to surfaces) for larger particles, and Brownian diffusion for smaller sub-micron particles. Size of particles drives atmospheric longevity. The lifetime of smaller particles exceeds that of larger particles. Studies by her team have shown that dry deposition influences the lifetime of particles, and that widely used parameterisations poorly capture the size-dependence of observations. Current models overestimate cooling effects over land from direct radiative effects and substantially underestimate indirect cooling effects. She recommended model revision.
Summary
This desktop series provided an opportunity for the RSC to showcase its relatively new series of Environmental Science journals, researchers to publicise their work to a wide audience, whilst the range of themes examined in the presentations and the short, on-line format has enabled very many attendees to deepen their understanding, or investigate a new area of knowledge. It has been a welcome initiative.
References
- Environmental Science: Nano (https://www.rsc.org/journals-books-databases/about-journals/environmental-science-nano/)
- Environmental Science: Water Research and Technology Associate Editor (https://www.rsc.org/journals-books-databases/about-journals/environmental-science-water-research-technology/)
- Environmental Science: Atmospheres (https://www.rsc.org/journals-books-databases/about-journals/environmental-science-atmospheres/)
- Environmental Science: Processes and Impacts (https://www.rsc.org/journals-books-databases/about-journals/environmental-science-processes-impacts/)
