Assessment of Environmental and Occupational Risk Factors for the Mitigation and Containment of a COVID-19 Outbreak in a Meat Processing Plant.

Throughout the COVID-19 pandemic, meat processing plants have been vulnerable to outbreaks of SARS-CoV-2 infection. Transmission of the virus is difficult to control in these settings because of a combination of factors including environmental conditions and the specific nature of the work. This paper describes a retrospective outbreak investigation in a meat processing plant, a description of the measures taken to prevent or contain further outbreaks, and insights on how those with specific knowledge of the working environment of these plants can collaborate with public health authorities to ensure optimal outbreak control.

Containment of procedure-associated aerosols by an extractor tent: effect on nebulized drug particle dispersal.

Background: Several medical procedures involving the respiratory tract are considered as 'aerosol-generating procedures'. Aerosols from these procedures may be inhaled by bystanders, and there are consequent concerns regarding the transmission of infection or, specific to nebulized therapy, secondary drug exposure.

Aim: To assess the efficacy of a proprietary high-efficiency-particulate-air-filtering extractor tent on reducing the aerosol dispersal of nebulized bronchodilator drugs.

Effectiveness of a plasma treatment device on microbial air quality in a hospital ward, monitored by culture.

This study analysed the effectiveness of plasma treatment on airborne bacteria and surface counts during a 14-day intervention within a four-bedded bay in an adult respiratory ward at Cork University Hospital, Ireland. One-hundred-litre air samples were collected twice daily every weekday for 4 weeks, with settle plates and surface swabs. The plasma treatment did not have an effect on airborne bacteria and fungi that was detectable by culture.

Atmospheric Biodetection Part I: Study of Airborne Bacterial Concentrations from January 2018 to May 2020 at Saclay, France.

The monitoring of bioaerosol concentrations in the air is a relevant endeavor due to potential health risks associated with exposure to such particles and in the understanding of their role in climate. In this context, the atmospheric concentrations of bacteria were measured from January 2018 to May 2020 at Saclay, France. The aim of the study was to understand the seasonality, the daily variability, and to identify the geographical origin of airborne bacteria.

A comparison of on-line and off-line bioaerosol measurements at a biowaste site.

An air measurement campaign was carried out at a green-waste composting site in the South of Ireland during Spring 2016. The aim was to quantify and identify the levels of Primary Biological Aerosol Particles (PBAP) that were present using the traditional off-line, impaction/optical microscopy method alongside an on-line, spectroscopic approach termed WIBS (Wideband Integrated Bioaerosol Sensor), which can provide number concentrations, sizes and "shapes" of airborne PBAP in real-time by use of Light Induced Fluorescence (LIF). The results from the two techniques were compared in order to validate the use of the spectroscopic method for determining the releases of the wide-range of PBAP present there as a function of site activity and meteorological conditions.

On-line monitoring of airborne bioaerosols released from a composting/green waste site.

This study is the first to employ the on-line WIBS-4 (Wideband Integrated Bioaerosol Sensor) technique for the monitoring of bioaerosol emissions and non-fluorescing "dust" released from a composting/green waste site. The purpose of the research was to provide a "proof of principle" for using WIBS to monitor such a location continually over days and nights in order to construct comparative "bioaerosol site profiles". The real-time data obtained was then used to assess variations of the bioaerosol counts as a function of size, "shape", site location, working activity levels, time of day, relative humidity, wind speeds and wind directions.

Cold-surface photochemistry of selected organic nitrates.

Reflection-absorption infrared (RAIR) spectroscopy has been used to explore the low temperature condensed-phase photochemistry of atmospherically relevant organic nitrates for the first time. Three alkyl nitrates, methyl, isopropyl, and isobutyl nitrate together with a peroxyacyl nitrate, peroxyacetyl nitrate (PAN), were examined. For the alkyl nitrates, similar photolysis products were observed whether they were deposited neat to the gold substrate or codeposited with water.

Single-particle speciation of alkylamines in ambient aerosol at five European sites.

Alkylamines are associated with both natural and anthropogenic sources and have been detected in ambient aerosol in a variety of environments. However, little is known about the ubiquity or relative abundance of these species in Europe. In this work, ambient single-particle mass spectra collected at five sampling sites across Europe have been analysed for their alkylamine content.

Apportionment of urban aerosol sources in Cork (Ireland) by synergistic measurement techniques.

The sources of ambient fine particulate matter (PM2.5) during wintertime at a background urban location in Cork city (Ireland) have been determined. Aerosol chemical analyses were performed by multiple techniques including on-line high resolution aerosol time-of-flight mass spectrometry (Aerodyne HR-ToF-AMS), on-line single particle aerosol time-of-flight mass spectrometry (TSI ATOFMS), on-line elemental carbon-organic carbon analysis (Sunset_EC-OC), and off-line gas chromatography/mass spectrometry and ion chromatography analysis of filter samples collected at 6-h resolution.

The effect of freezing on reactions with environmental impact.

The knowledge that the freezing process can accelerate certain chemical reactions has been available since the 1960s, particularly in relation to the food industry. However, investigations into such effects on environmentally relevant reactions have only been carried out since the late 1980s. Some 20 years later, the field has matured and scientists have conducted research into various important processes such as the oxidation of nitrite ions to nitrates, sulfites to sulfates, and elemental mercury to inorganic mercury.

Freeze-induced formation of bromine/chlorine interhalogen species from aqueous halide ion solutions.

Both gaseous bromine and bromine chloride have been monitored in polar environments and implicated in the destruction of tropospheric ozone. The formation mechanisms operating for these halogen compounds have been suggested previously. However, few laboratory studies have been performed using environmentally relevant concentrations of bromide and chloride ions in polar ice mimics.

Cold-surface photochemistry of primary and tertiary alkyl nitrites.

Reflection-absorption infrared spectroscopy (RAIRS) is used to explore the photochemistry of primary and tertiary alkyl nitrites deposited on a gold surface. The primary alkyl nitrites examined for this study were n-butyl, isobutyl, and isopentyl nitrite. These compounds showed qualitatively similar spectra to those observed in previous condensed-phase measurements.

Dark oxidation of dissolved gaseous mercury in polar ice mimics.

The low-temperature chemistry associated with environmentally available mercury has recently attracted considerable scientific interest due to the discovery of systemic gas-phase mercury depletion events (MDEs) which occur periodically at the poles. However, the fate of the mercury once it enters the snowpack is not fully understood, even its chemical speciation has yet to be well characterized. An issue that is of particular concern in frozen environments is the transformation of elemental mercury (Hg(0)) to more bioavailable oxidized forms, which can then be methylated by biotic and abiotic processes.

Characterization of sulfurous acid, sulfite, and bisulfite aerosol systems.

Acidic tropospheric aerosols contain inorganic species such as sulfurous acid (H(2)SO(3)). As the main alkaline species, ammonia (NH(3)) plays an important role in the heterogeneous neutralization of these acidic aerosols. An aerosol flow-tube apparatus was used to obtain simultaneous optical and size distribution measurements using FTIR and SMPS measurements, respectively, as a function of relative humidity and aerosol chemical composition.

The use of polar organic compounds to estimate the contribution of domestic solid fuel combustion and biogenic sources to ambient levels of organic carbon and PM2.5 in Cork Harbour, Ireland.

PM(2.5) samples collected at Cork Harbour, Ireland during summer, autumn, late autumn and winter, 2008-2009 were analyzed for polar organic compounds that are useful markers for aerosol source characterization. The determined compounds include tracers for biomass burning primary particles, fungal spores, markers for secondary organic aerosol (SOA) from isoprene, α-/β-pinene, and d-limonene.

Freeze-induced reactions: formation of iodine-bromine interhalogen species from aqueous halide ion solutions.

Interhalide ion formation resulting from the freezing of dilute solutions containing components found in natural sea salt are investigated as a potential mechanism for the release of interhalogens to the polar atmosphere. Acidified solutions containing iodide, bromide, and nitrite ions have been frozen and then thawed, with changes in speciation analyzed using UV-visible spectrophotometry. The freezing process is shown to induce the formation of the important interhalide ion, IBr(2)(-).

Protonated nitrosamide and its potential role in the release of HONO from snow and ice in the dark.

A joint Fourier transform reflection absorption infrared spectroscopy/thermal programmed desorption (RAIRS/TPD) study has provided good evidence for the existence of protonated nitrosamide (NH₃NO(+)) on surfaces at cold temperatures. This species has long been proposed to exist in studies of the DeNO(x) process and the decomposition of ammonium nitrite. In the context of the current experiments, performed at low-temperatures in the absence and presence of water-ice, the results provided a firm mechanistic basis for understanding the release of HONO from snowpack in a "dark" mechanism and also under alkaline surface conditions.

Airborne emissions in the harbour and port of Cork.

It is now accepted that the transport sector is responsible for a large and growing share of global emissions affecting both health and climate. The quantification of these effects requires, as an essential first step, a comprehensive analysis and characterization of the contributing subsectors, i.e.

Large pore bi-functionalised mesoporous silica for metal ion pollution treatment.

Here we demonstrate aminopropyl and mercatopropyl functionalised and bi-functionalised large pore mesoporous silica spheres to extract various metal ions from aqueous solutions towards providing active sorbents for mitigation of metal ion pollution. Elemental analysis (EA) and FTIR techniques were used to quantify the attachment of the aminopropyl and mercatopropyl functional groups to the mesoporous silica pore wall. Functionalisation was achieved by post-synthesis reflux procedures.

Release of nitric oxide and iodine to the atmosphere from the freezing of sea-salt aerosol components.

The known room-temperature, solution-phase reaction between nitrite ions and iodide ions, which occurs in acidic conditions (pH < 5.5), is shown to be accelerated when neutral aqueous solutions are frozen. The reaction is proposed to occur in liquid "micropockets" within the ice structure at temperatures between the freezing point and the eutectic temperature.

Cirrus cloud mimics in the laboratory: an infrared spectroscopy study of thin films of mixed ice of water with organic acids and ammonia.

The structures of formic and acetic acids deposited on a thin gold substrate held in vacuum at low temperatures and their related water-ice promoted chemistry have been investigated. The condensed water/guest films were taken to act as cirrus cloud "mimics." Such laboratory representations provide a necessary prelude to understanding how low temperature surfaces can affect chemical composition changes in the upper atmosphere.

Potential role of the nitroacidium ion on HONO emissions from the snowpack.

The effects of photolysis on frozen, thin films of water-ice containing nitrogen dioxide (as its dimer dinitrogen tetroxide) have been investigated using a combination of Fourier transform reflection-absorption infrared (FT-RAIR) spectroscopy and mass spectrometry. The release of HONO is ascribed to a mechanism in which nitrosonium nitrate (NO+NO3-) is formed. Subsequent solvation of the cation leads to the nitroacidium ion, H2ONO+, i.

Spectroscopic and optimization modeling study of nitrous acid in aqueous solution.

Nitrous acid (HONO) and the nitrite ion represent a particularly important conjugate pair of trace species with regard to heterogeneous behavior within the bulk, and on the surface, of aqueous atmospheric dispersions: this role results from their chemical reactivity, photolysis pathways, solubility, and ambient concentration levels. The actual ratio of NO(2)(-): HONO in solution is determined by the pH and the nitrous acid dissociation constant (pK(a)) which is generally quoted in the literature as 3.27 at 298 K.

Freezing halide ion solutions and the release of interhalogens to the atmosphere.

The effect of freezing on a variety of acidified and neutral, nitrite ion and halide-containing mixtures has been investigated using UV/vis spectroscopy. Several trihalide ions were formed and monitored, including I(2)Cl(-), I(2)Br(-), ICl(2)(-) and IBr(2)(-). A mechanism to explain the observations is given in terms of steps involving INO and the nitroacidium ion, [H(2)ONO](+).

Cadmium-specific formation of metal sulfide 'Q-particles' by Klebsiella pneumoniae.

Klebsiella pneumoniae overcomes cadmium toxicity through the 'biotrans-formation' of cadmium ions into photoactive, nanometre-sized CdS particles deposited on the cell surface. The kinetics of particle formation during batch culture growth was monitored by electron microscopy (EM), energy-dispersive X-ray analysis and electronic absorption spectroscopy (EAS). During the deceleration phase of bacterial growth, the presence of CdS particles on the outer cell wall of K.