The environmental impact of silver nanoparticles (AgNP) has become a topic of interest recently, this is due to the fact that AgNPs have been included in numerous consumer products including ...textiles, medical products, domestic appliances, food containers, cosmetics, paints and nano-functionalised plastics. The production, use and disposal of these AgNP containing products are potential routes for environmental exposure. These concerns have led to a number of studies investigating the release of particles from nano-functionalised products, the detection of the particles in the aquatic environment and the potential environmental toxicology of these AgNPs to aquatic organisms. The overall aim of this review is to examine methods for the capture and detection of AgNPs, potential toxicity and transmission routes in the aquatic environment.
Display omitted
•AgNPs are likely to be released into the environment during the lifecycle of consumer products.•The complex environmental fate of silver nanoparticles in aquatic systems is influenced by numerous factors.•The detection and characterisation of silver nanoparticles in environmental waters is difficult.•Variability in Ag and AgNP characteristics eluted to the environment leads to uncertainty in ecotoxicological assessments.•A standardised approach to toxicity testing on silver nanomaterials is needed to comprehensively assess their toxicity.
•Fluoroquinolones (FQs) are reserve antimicrobials when no alternative treatment is available.•FQs are often prescribed as first-line treatment for less severe infections in primary care.•Central ...nervous system (CNS)- and gastrointestinal (GI)-related AEs with FQs three times that of any other antimicrobial.•Total AEs similar for FQs and other antimicrobials; more total AEs and GI-related AEs for co-amoxiclav compared with FQs.•No difference identified for skin-related or overall risk of AEs compared to any other antimicrobial.
Fluoroquinolones (FQs) are second-line antimicrobial agents. Once the decision to prescribe an antimicrobial is made, the choice of antimicrobial should be based on both the benefits and adverse effects. This systematic review quantifies the occurrence of common adverse events (AEs) related to FQs in relation to any other antimicrobial for any indication in primary care.
We searched randomized controlled trials from Embase, PubMed, Cochrane Central Register of Controlled Trials and CINHAL. FQs had to be administered orally, for any indication, to adults and in primary care. Data were extracted independently in standard forms in “Covidence”. Pooled estimates of the intervention effects for AEs were determined by the Peto odds ratios (ORs) and 95% confidence intervals (CIs) in Revman.
In the 39 studies selected, the most commonly reported AEs were nausea, vomiting, diarrhoea, headache, dizziness, and rash. A meta-analysis of 28 studies reporting AEs showed central nervous system (CNS)-related AEs (OR 1.40 (1.12-1.75) P = 0.003, heterogeneity (I2) = 0%) and gastrointestinal (GI)-related AEs (OR 1.20 (1.06-1.36) P = 0.005, I2 = 80%) were significantly associated with FQs compared with other antimicrobials. Compared with FQs, co-amoxiclav showed significantly more total AEs (OR 0.70 (0.54-0.90) P = 0.006, I2 = 78%) and GI-related AEs (OR 0.69 (0.52-0.91) P = 0.008, I2 = 94%). Withdrawal or discontinuation due to drug-related AEs was higher for FQs (OR 1.19 (1.00-1.42) P = 0.05, I2 = 5%). Sensitivity analyses did not change these results.
FQs are associated with more CNS- and GI-related AEs compared with other types of antimicrobial. This information is relevant to support decision making in relation to antimicrobial prescribing.
Salmonella enterica subsp. enterica serovar Dublin (S. Dublin) is one of the non-typhoidal Salmonella (NTS); however, a relatively high proportion of human infections are associated with invasive ...disease. We applied whole genome sequencing to representative invasive and non-invasive clinical isolates of S. Dublin to determine the genomic variations among them and to investigate the underlying genetic determinants associated with invasiveness in S. Dublin. Although no particular genomic variation was found to differentiate in invasive and non-invasive isolates four virulence factors were detected within the genome of all isolates including two different type VI secretion systems (T6SS) encoded on two Salmonella pathogenicity islands (SPI), including SPI-6 (T6SSSPI-6) and SPI-19 (T6SSSPI-19), an intact lambdoid prophage (Gifsy-2-like prophage) that contributes significantly to the virulence and pathogenesis of Salmonella serotypes in addition to a virulence plasmid. These four virulence factors may all contribute to the potential of S. Dublin to cause invasive disease in humans.
Shiga toxigenic Escherichia coli (STEC) are pathogenic E. coli that cause infectious diarrhoea. In some cases infection may be complicated by renal failure and death. The incidence of human infection ...with STEC in Ireland is the highest in Europe. The objective of the study was to examine the spatial incidence of human STEC infection in a region of Ireland with significantly higher rates of STEC incidence than the national average and to identify possible risk factors of STEC incidence at area level. Anonymised laboratory records (n = 379) from 2009 to 2015 were obtained from laboratories serving three counties in the West of Ireland. Data included location and sample date. Population and electoral division (ED) data were obtained from the Irish 2011 Census of Population. STEC incidence was calculated for each ED (n = 498) and used to map hotspots/coldspots using the Getis-Ord Gi* spatial statistic and significant spatial clustering using the Anselin's Local Moran's I statistic. Multivariable regression analysis was used to consider the importance of a number of potential predictors of STEC incidence. Incidence rates for the seven-year period ranged from 0 to 10.9 cases per 1000. A number of areas with significant local clustering of STEC incidence as well as variation in the spatial distribution of the two main serogroups associated with disease in the region i.e. O26 and O157 were identified. Cattle density was found to be a statistically significant predictor of STEC in the region. GIS analysis of routine data indicates that cattle density is associated STEC infection in this high incidence region. This finding points to the importance of agricultural practices for human health and the importance of a “one-health” approach to public policy in relation to agriculture, health and environment.
Display omitted
•GIS applied to infectious disease incidence in country with highest EU rates•Cattle density associated with human STEC incidence in the West of Ireland•Significant local clustering of STEC incidence in the region•GIS can aid targeting public health resources for reduction of infectious disease.•“One-health” approach necessary for public health policy
Silver nanoparticles (AgNPs), due to their antibacterial activity, have been incorporated into numerous consumer products. Their environmental impact however, is currently unclear. Uncertainties ...surround the concentration, fate, and effects of AgNPs in aquatic environments. This study examined the suitability of activated charcoal as a capture material for AgNPs from water. Samples of 100 ppb AgNPs were initially generated and exposed to activated charcoal for 24 h to examine the ability of charcoal to capture AgNPs. The decrease in Ag concentration was measured using ICP-MS. Following initial investigations, the surface area of the charcoal was increased firstly with a pestle and mortar and secondly by milling the charcoal using a ball mill. The increased surface area of the milled charcoal increased the capture of the AgNPs from 11.9% to 63.6% for the 100 ppb samples. Further investigations were carried out examining the effect on the capture of AgNP concentration (with concentration ranging from 10 to 100 ppb), particle coating and the effect of exposure time to the activated charcoal. The capture of AgNP increased with decreasing concentration. A hydrochloric acid (HCl) leaching procedure was also developed which successfully removed the captured silver allowing the fraction captured by the charcoal to be quantified with an average of 94.8% recovery. The results show that milled activated charcoal, can successfully capture AgNPs from water samples, and that therefore, activated charcoal may prove to be a cost effective material for the remediation of waters impacted by AgNP or other nano-wastes.
Display omitted
•Activated charcoal is a suitable material for the capture of silver nanoparticles from water samples•Milled activated charcoal successfully captured 63.6% of the silver in 100 ppb 25 nm AgNP samples•AgNP capture increased with decreasing concentration and increasing the time that the sample was exposed to the charcoal•Changing the size and coating of the AgNPs used to 10 nm citrate AgNPs did not inhibit the capture by the milled charcoal•An average of 94.8% of the Ag captured by the charcoal was recovered through the development of an HCl leaching procedure
The European, multicentre, quarterly point-prevalence study of community-acquired diarrhoea (EUCODI) analysed stool samples received at ten participating clinical microbiology laboratories (Austria, ...Finland, France, Germany, Greece, Ireland, Italy, Portugal, Romania, and the UK) in 2014. On four specified days, each local laboratory submitted samples from ≤20 consecutive patients to the Austrian Study Centre for further testing with the FilmArray GI Panel (BioFire Diagnostics, Salt Lake City, UT, USA). Of the 709 samples from as many patients received, 325 (45.8%) tested negative, 268 (37.8%) yielded only one organism, and 116 (16.4%) yielded multiple organisms. Positivity rates ranged from 41% (30 of 73 samples) in France to 74% (59 of 80 samples) in Romania. With the exception of Entamoeba histolytica and Vibrio cholerae, all of the 22 targeted pathogens were detected at least once. Enteropathogenic Escherichia coli, Campylobacter species, toxigenic Clostridium difficile, enteroaggregative E. coli, norovirus and enterotoxigenic E. coli were the six most commonly detected pathogens. When tested according to local protocols, seven of 128 positive samples (5.5%) yielded multiple organisms. Overall, the FilmArray GI Panel detected at least one organism in 54.2% (384/709) of the samples, as compared with 18.1% (128/709) when testing was performed with conventional techniques locally. This underlines the considerable potential of multiplex PCR to improve routine stool diagnostics in community-acquired diarrhoea. Classic culture methods directed at the isolation of specific pathogens are increasingly becoming second-line tools, being deployed when rapid molecular tests give positive results. This optimizes the yield from stool examinations and dramatically improves the timeliness of diagnosis.
The reuse of treated municipal sewage (‘biosolids’) on land is an effective method to divert waste away from landfill and to use an alternative, low cost method of fertilisation. While legislation ...has mainly focused on the control of nutrient and metal application rates to land, other potentially harmful emerging contaminants (ECs) may be present in biosolids. Up to 80% of municipal sewage sludge is reused in agriculture in Ireland, which is currently the highest rate of reuse in Europe. However, unlike other countries, no study has been conducted on the presence of ECs across a range of wastewater treatment plants (WWTPs) in this country. This study evaluated the concentrations of two ECs in sewage sludge, the antimicrobials triclosan (TCS) and triclocarban (TCC), and their presence in surface runoff following land application in controlled rainfall simulation studies. In 16 WWTPs, concentrations of TCS and TCC were 0.61 and 0.08µgg−1, which is at the lower end of concentrations measured in other countries. The concentrations in runoff post land application were also mainly below the limits of detection (90ngL−1 for TCS, 6ngL−1 for TCC), indicating that runoff is not a significant pathway of entry into the environment.
Display omitted
•Triclosan and triclocarban measured in biosolids from 16 WWTPs in Ireland.•Agricultural surface runoff of triclocarban and triclocarban also measured.•Concentrations of triclosan and triclocarban in runoff at or below LOD.
In this study, New Delhi metallo-beta-lactamase (NDM)-producing Enterobacteriaceae were identified in Irish recreational waters and sewage. Indistinguishable NDM-producing Escherichia coli by ...pulsed-field gel electrophoresis were isolated from sewage, a fresh water stream and a human source. NDM-producing Klebsiella pneumoniae isolated from sewage and seawater in the same area were closely related to each other and to a human isolate. This raises concerns regarding the potential for sewage discharges to contribute to the spread of carbapenemase-producing Enterobacteriaceae.
Treated municipal sewage sludge (“biosolids”) and dairy cattle slurry (DCS) may be applied to agricultural land as an organic fertiliser. This study investigates losses of nutrients in runoff water ...(nitrogen (N) and phosphorus (P)), metals (copper (Cu), nickel (Ni), lead (Pb), zinc (Zn), cadmium (Cd), chromium (Cr)), and microbial indicators of pollution (total and faecal coliforms) arising from the land application of four types of treated biosolids and DCS to field micro-plots at three time intervals (24, 48, 360h) after application. Losses from biosolids-amended plots or DCS-amended plots followed a general trend of highest losses occurring during the first rainfall event and reduced losses in the subsequent events. However, with the exception of total and faecal coliforms and some metals (Ni, Cu), the greatest losses were from the DCS-amended plots. For example, average losses over the three rainfall events for dissolved reactive phosphorus and ammonium-nitrogen from DCS-amended plots were 5 and 11.2mgL−1, respectively, which were in excess of the losses from the biosolids plots. When compared with slurry treatments, for the parameters monitored biosolids generally do not pose a greater risk in terms of losses along the runoff pathway. This finding has important policy implications, as it shows that concern related to the reuse of biosolids as a soil fertiliser, mainly related to contaminant losses upon land application, may be unfounded.
Display omitted
•This study investigated surface runoff of contaminants from biosolids in field plots.•Contaminants investigated were nutrients, metals, microbes and trace elements.•Compared to slurry, biosolids do not pose a greater risk of contaminant losses.•Fears concerning contaminant losses from land applied biosolids may be unfounded.
PDF
