Microplastics in water: Occurrence, fate and removal.

A global study on tap water samples has found that up to 83% of these contained microplastic fibres. These findings raise concerns about their potential health risks. Ingested microplastic particles have already been associated with harmful effects in animals, which raise concerns about similar outcomes in humans. Microplastics are ubiquitous in the environment, commonly found disposed in landfills and waste sites. Within indoor environments, the common sources are synthetic textiles, plastic bottles, and packaging. From the various point sources, they are globally distributed through air and water and can enter humans through various pathways. The finding of microplastics in fresh snow in the Antarctic highlights just how widely they are dispersed. The behaviour and health risks from microplastic particles are strongly influenced by their physicochemical properties, which is why their surfaces are important. Surface interactions are also important in pollutant transport via adsorption onto the microplastic particles. Our review covers the latest findings in microplastics research including the latest statistics in their abundance, their occurrence and fate in the environment, the methods of reducing microplastics exposure and their removal. We conclude by proposing future research directions into more effective remediation methods including new technologies and sustainable green remediation methods that need to be explored to achieve success in microplastics removal from waters at large scale.

Electro-flocculation of aquaculture wastewater microalgal communities reduces nutrient loading.

Land-based aquaculture provides dietary protein to the world's population in a sustainable way, but issues related to release of nitrogen rich wastewater limits its expansion. Sedimentation of naturally occurring microalgae that assimilate excess nitrogen, is slow and land intensive. Electro-flocculation, used in wastewater treatment processes, is a potential alternative for aquaculture. Trials of different electro-flocculation configurations applied to three prawn farm pondwater samples containing varying microalgal assemblages are reported. In 64 % of trials, electro-flocculation reduced total nitrogen (TN) and dissolved inorganic nitrogen (DIN) loads within regulatory limits.TN was reduced up to 83.2 % (10.93 to 1.83 mg.L-1) within 20 mins in stationary water, and DIN to 90.6 % (3.19 to 0.30 mg.L-1) in 102 mins trials in flowing water. Bellerochea andGloeocapsa spp. were dominant in wastewater. The role of microalgal community composition on flocculation is discussed, including evidence Bellerocheapromotes flocculation. This study confirmed electro-flocculation quickly reduces TN and DIN.

Nanotechnologically Relevant Aspects of COVID-19 Vaccines.

The COVID-19 pandemic has affected several facets of human existence globally. To counter the spread of the virus, several vaccines have been developed and administered worldwide, using various technologies. Due to the need for the mRNA to be safely 'protected' until it can reach the host's cells, innovative transport, casing, stabilization and attachment mechanisms need to be harnessed to accompany the mRNA. Nanotechnology has featured in several such capacities. Therefore, our short review explores the role of nanomaterials in COVID vaccines, with a core focus on those based on mRNA. Often, the chemistry of these nanomaterials is critical to their success in these, and such important aspects are highlighted in our review. Towards the end, we have also discussed the various vaccine types.

Guilty by association: Assessment of environmental loadings on arsenic distribution in two Pacific Island rivers.

This work evaluates the immediate risk of arsenic toxicity in two major river systems located in Western Viti Levu, Fiji and Guadalcanal, the Solomon Islands. Using principal component analysis, the associations between the major inorganic arsenic species, As (V) and As(III) and those of the controlling parameters, pH, dissolved oxygen and temperature were investigated in these aquatic systems. As(III) was found to be the dominant form of total inorganic As concentrations in five of the thirteen sites studied. There remains a high risk of As(III) exposure from these sites in the rivers. The study also examined the potential role of mine adits in influencing the distinct water chemistry at the sites. Over 50% of As was found to exist as the more toxic As(III) species at some sites (with higher levels near the gold mines) in both river systems. This finding implies that there may be health risk to populations relying on the river waters for agriculture. As(V) at most sites across both rivers exceeded 13 µg/L, defined as a trigger value for aquatic ecosystems by Australia and New Zealand standards. The PCA indicated that spatial variations play a significant role in water chemistries between sites further from the mine adit location in the Metapona River. In the Sabeto River system, there was also considerable intra-variability in the water chemistries between sites. Further detailed studies are necessary to determine a complete profile of As species and associated biogeochemical processes in these rivers which could lead on to identify appropriate containment or mitigation measures.

First Assessment of Metals Contamination in Road Dust and Roadside Soil of Suva City, Fiji.

Studies have claimed that road dust and roadside soil are potential banks of pollutants generally in urban areas. Thus, quantifying the concentrations of metals in an urban area is a prerequisite for assessing pollution and their health effects. Hence, this study reports the concentration of the metals, such as Cd, Co, Cr, Ni, Cu, Pb, Zn, and Fe, in the road dust and the roadside soil of Suva City. A total number of 45 road dust and 36 roadside soil samples were collected at 18 different locations around Suva City with potential traffic influence and analysed. The respective metals concentration in the road dust and roadside soil samples of Suva City were Cd (3.7 and 3.1 mg/kg), Co (35.0 and 33.2 mg/kg), Cr (40.0 and 34.0 mg/kg), Ni (54.3 and 32.4 mg/kg), Cu (172.3 and 265.7 mg/kg), Pb (71.0 and 59.3 mg/kg), Zn (685.0 and 507.0 mg/kg), and Fe (41,010.4 and 39,525.5 mg/kg) and showed the decreasing order as Fe > Zn > Cu > Pb > Ni > Cr > Co > Cd and Fe > Zn > Cu > Pb > Cr > Co > Ni > Cd for road dust and roadside soil, respectively. Furthermore, the mean values of the metals surpassed their background levels, except for Fe, whereas the mean values of Cd, Ni, Cu, and Zn have exceeded their permissible limits in road dust. Similarly, Cd, Cu, and Zn have exceeded their permissible limit in roadside soil except for Ni. The geo-accumulation index (Igeo) assessment of Suva City road dust thus indicated nonpolluted to moderate pollution by Ni and Cu and moderate pollution by Zn. The Igeo assessment of the roadside soil showed moderately polluted by Cu and Zn but no pollution from the remaining studied metals. Overall, the study indicated that the sampling locations at an industrial site of Suva City is highly predominated with almost all of the studied metals and is a concern to the general public who live and work within the vicinity of Walu Bay industrial area.

Parkinson's Disease and the Environment.

Parkinson's disease (PD) is a heterogeneous neurodegenerative disorder that affects an estimated 10 million sufferers worldwide. The two forms of PD include familial and sporadic, and while the etiology of PD is still largely unknown, the condition is likely to be multifactorial with genetic and environmental factors contributing to disease genesis. Diagnosis of the condition is attained through the observation of cardinal clinical manifestations including resting tremor, muscle rigidity, slowness or loss of movement, and postural instability. Unfortunately, by the time these features become apparent extensive neurological damage has already occurred. A cure for PD has not been identified and the current therapy options are pharmaceutical- and/or surgical-based interventions to treat condition symptoms. There is no specific test for PD and most diagnoses are confirmed by a combination of clinical symptoms and positive responses to dopaminergic drug therapies. The prevalence and incidence of PD vary worldwide influenced by several factors such as age, gender, ethnicity, genetic susceptibilities, and environmental exposures. Here, we will present environmental factors implicated in sporadic PD onset. By understanding the mechanisms in which environmental factors interact with, and affect the brain we can stride toward finding the underlying cause(s) of PD.

Determining meat freshness using electrochemistry: Are we ready for the fast and furious?

Electrochemistry is providing a variety of sensors at an extremely rapid pace. Many of these sensors offer powerful attributes like a multitude of platforms like voltammetry, impedimetry, amperometry and conductometry, as well as sensor-related gains like high sensitivity, selectivity and low cost. It is natural that their applications to food, especially meat freshness determination, are also increasing. Novel methods for rapidly assessing meat freshness are vital for meeting the increasing worldwide demand for meat products. Therefore, we present a short and succinct review of the most promising electrochemical sensor types, including those based on conductive polymers, nanocomposites and metal nanoparticles. From the wide range of sensors that have been designed to detect microbial pathogens and chemical degradation, we have covered a basic snapshot to yield an impression of recent gains in the research genre of meat freshness.

Graphene, electrospun membranes and granular activated carbon for eliminating heavy metals, pesticides and bacteria in water and wastewater treatment processes.

Access to safe water has a significant impact on all parts of society, its growth and sustainability, both politically and socioeconomically. Consequently, the preservation of water and wastewater treatment have become a global challenge. A major contributor to water pollution is improperly or untreated industrial emissions; water resources can be contaminated with harmful pollutants, toxins or pathogenic microorganisms. Carbon's unique chemistry and its evolution due to recent advances in carbon-based technologies such as nanomaterials, offer significant potential for a variety of water purification strategies. This work details the application of carbon materials in combination with nanotechnology in the form of graphene, graphene composites, electrospun membranes and improved activated carbon in a myriad of water treatment systems with an emphasis on the removal of heavy metals, pesticides and harmful bacteria.

Handling Complexity in Animal and Plant Science Research-From Single to Functional Traits: Are We There Yet?

The current knowledge of the main factors governing livestock, crop and plant quality as well as yield in different species is incomplete. For example, this can be evidenced by the persistence of benchmark crop varieties for many decades in spite of the gains achieved over the same period. In recent years, it has been demonstrated that molecular breeding based on DNA markers has led to advances in breeding (animal and crops). However, these advances are not in the way that it was anticipated initially by the researcher in the field. According to several scientists, one of the main reasons for this was related to the evidence that complex target traits such as grain yield, composition or nutritional quality depend on multiple factors in addition to genetics. Therefore, some questions need to be asked: are the current approaches in molecular genetics the most appropriate to deal with complex traits such as yield or quality? Are the current tools for phenotyping complex traits enough to differentiate among genotypes? Do we need to change the way that data is collected and analysed?

There is gold in them hills: Predicting potential acid mine drainage events through the use of chemometrics.

Disused mines and mining legacy require significant manpower to ameliorate the contaminated environmental surroundings following their disbanding coupled with extraordinary funding to manage these issues. Water (pH, temperature, dissolved oxygen, conductance, metals, sulphate) and total suspended solids (TSS) quality are environmental parameters that are affected by legacy mining activity and often require monitoring and rapid response if events (e.g. rainfall) occur which might affect the surrounding areas. In this study, we have monitored a famous mine site in Queensland, Australia for a number of water and sediment parameters known to be associated with acid mine drainage. This study performed analysis of water and sediment over three years, as well as rainfall data. Principal component analysis (PCA) and partial least squares (PLS) regression was undertaken to investigate the data obtained. It was found that the use of PCA can predict the effect of year and site on the environmental influence of the abandoned mine site, based on the combination of chemical properties and meteorological data.

Biomimetics for early stage biofouling prevention: templates from insect cuticles.

A biomimetic antifouling material study was carried out utilising superhydrophobic cicada and dragonfly wings replicated with a polymer (epoxy resin). They were tested in a marine biofouling study for up to 1 week in addition to biofouling assays of protein, carbohydrate and DNA absorption. The materials were compared against a commercial antifouling paint and a polymeric smooth surface constituting a control sample. The replicated surfaces demonstrated superior antifouling properties in comparison to the control and similar efficiency in DNA (10% reduction), protein and carbohydrate adsorption (15%) to the commercial anti-fouling paint. As the fabricated surfaces have roughness at the nanometre scale it is probable that the low adsorption properties, at least in the early stages, may be related to air trapped at the surface. Interestingly the most disordered replicated surface (dragonfly wing replicate) demonstrated the lowest values of absorption.

Minimizing fouling at hydrogenated conical-tip carbon electrodes during dopamine detection in vivo.

In this paper, physically small conical-tip carbon electrodes (∼2-5 µm diameter and ∼4 µm axial length) were hydrogenated to develop a probe capable of withstanding fouling during dopamine detection in vivo. Upon hydrogenation, the resultant hydrophobic sp(3) carbon surface deters adsorption of amphiphilic lipids, proteins, and peptides present in extracellular fluid and hence minimizes electrode fouling. These hydrogenated carbon electrodes showed a 35% decrease in sensitivity but little change in the limit of detection for dopamine over a 7-day incubation in a synthetic laboratory solution containing 1.0% (v/v) caproic acid (a lipid), 0.1% (w/v) bovine serum albumin and 0.01% (w/v) cytochrome C (both are proteins), and 0.002% (w/v) human fibrinopeptide B (a peptide). Subsequently, during dopamine detection in vivo, over 70% of the dopamine oxidation current remained after the first 30 min of a 60-min experiment, and at least 50% remained over the next half-period at the hydrogenated carbon electrodes. On the basis of these results, an initial average electrode surface fouling rate of 1.2% min(-1) was estimated, which gradually declined to 0.7% min(-1). These results support minimal fouling at hydrogenated carbon electrodes applied to dopamine detection in vivo.