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According to the World Drugs Report (2019) from the United Nations on Drugs and Crime there were over half a million drug related deaths, 35 million people were treated for drug use disorders across the globe, and it is estimated that more than 270 million people used drugs during 2017. Lab-on-a-Chip (LOC) technology is an increasingly popular choice of detection method for drugs of abuse. We systematically reviewed the published literature available on LOC methods for the detection of drugs of abuse including New Psychoactive Substances (NPS) from January 1999 to March 2021 and identified 45 publications. A total of 28 different drugs of abuse were investigated, with cocaine the most widely studied (58%). The LOC devices were capable of accepting a wide range of biological and non-biological samples. A total of 18 countries have been involved in LOC research into detection of drugs of abuse, with locations generally following local trends in drug use. LOC devices employed a range of detection methods with immunoassays most commonly incorporated (34%). Recommendations are made for expanding the use of real-world samples, improved validation and further analysis of practicality (in terms of providing information on cost, speed of analysis and ease of use). More than a third of all the publications included in this review were published since 2019, representing a recent increase in research using LOC devices for the detection of drugs of abuse. There is currently an extensive range of LOC approaches available offering potential for these devices as cost-effective, rapid and portable detection systems.

This review represents a comprehensive analysis on pollutants in elasmobranchs including meta-analysis on the most studied pollutants: mercury, cadmium, PCBs and DDTs, in muscle and liver tissue. Elasmobranchs are particularly vulnerable to pollutant exposure which may pose a risk to the organism as well as humans that consume elasmobranch products. The highest concentrations of pollutants were found in sharks occupying top trophic levels (Carcharhiniformes and Lamniformes). A human health risk assessment identified that children and adults consuming shark once a week are exposed to over three times more mercury than is recommended by the US EPA. This poses a risk to local fishing communities and international consumers of shark-based products, as well as those subject to the widespread mislabelling of elasmobranch products. Wider screening studies are recommended to determine the risk to elasmobranchs from emerging pollutants and more robust studies are recommended to assess the risks to human health.

Natural flood management interventions, such as Large Wood Debris (LWD) or engineered log jams, are being increasingly deployed throughout the UK and elsewhere. In addition to alleviating flood risk, it is anticipated that they may influence the ecology of freshwater river systems, including macroinvertebrate populations. This study explores macroinvertebrate assemblages, water quality parameters, and sediment size distribution in a headwater stream following the addition of LWD as part of a natural flood management scheme. The study area consists of 6 sites within the intervention zone where LWD log jams were implemented, with comparative control sites upstream and downstream (3 sites each). Macroinvertebrate communities, sediment size distribution, and water chemistry were sampled 3 and 10 months following the addition of LWD. Our findings revealed increased macroinvertebrate abundance and taxa richness in the LWD intervention zone versus control, with an increased BMWP score reflecting the increased taxa richness. Average Score Per Taxon, and water chemistry showed no change, revealing invertebrate changes to be independent of water quality. NMDS and hierarchical clustering analysis on invertebrate data showed a clear separation of communities where LWD was present from those with no LWD, while SIMPER analysis showed that LWD addition led to the rapid establishment of taxa (Hydraenidae, Rhyacophilidae, Scirtidae, and Elmidae) that were otherwise absent. Ten months after LWD addition, improved biodiversity was also found in areas below the intervention zone, suggesting the positive impacts of LWD extend downstream. LWD also altered sediments, with sites immediately upstream of LWD log jams having a greater percentage of fine sediment than those immediately downstream. These results suggest that biological complexity and niche availability increased within the in-channel zone as a result of introduced LWD, thus revealing wider aquatic habitat improvement potential of LWD for natural flood management. The use of LWD as an intervention for flood management is recommended for its additional benefits for ecosystem health.

Changing economics in the 20th century led to losses and fragmentation of semi-natural woodland in Britain and to a reduction in active woodland management with many becoming increasingly neglected, even-aged and with closed canopy. Lack of woodland management is known to contribute to declines in some taxonomic groups, for example birds. However, the response of bats to changes in woodland structure are poorly understood. We compared two measures of bat activity, derived from static acoustic recorders across 120 sample plots in coppice, irregular high forest (uneven-aged, continuous cover) and limited intervention (under-managed, even-aged) management stands, within a large tract of ancient woodland in southern England. Bat species richness was highest in irregular high forest stands, and there were significant differences in occupancy rates for most bat species across stand management types. Coppice recorded low activity of several bat species and irregular high forest showed high occupancy rates, including for Barbastelle Barbastella barbastellus, which is IUCN listed as near threatened. The occupancy rates in stand management types differed for some bat species between mid- and late summer counts, suggesting seasonal variation in habitat use. Within stands, most bat species were associated with opened canopy, lower growing stocks and reduced densities of understorey, and to a lesser extent, with large-girthed trees and presence of deadwood snags. In some cases, species responded to a given habitat variable similarly across the three stand management types, whereas in others, the response differed among stand management types. For example, increased numbers of large-girthed trees benefitted a number of bat species within coppice where these were least common, but not in irregular stands. Irregular silviculture high forest appears to provide many of the structural attributes that positively influence occupancy of several woodland bat species, including Barbastella barbastellus.

4-methylmethcathinone (mephedrone) has emerged in drug seizures as a new psychoactive substance (NPS) causing a public health risk of global concern. Currently, there are no commercial microfluidic devices for the selective detection of mephedrone and so this study presents a simple, low-cost and portable paper-based Lab-on-a-Chip (LOC) device with colorimetric detection to fill this gap. Limits of detection for mephedrone in spiked urine and dissolved powder (aqueous) samples are clinically relevant at 4.34 ng mL−1 and 2.51 ng mL−1 respectively. No cross-reactivity for commonly encountered cutting agents, interferents and adulterants were detected. Mephedrone and its main metabolite were detectable in aqueous and urine samples within 3 min. Stability and reproducibility measurements showed no significant difference in signal intensity over eight weeks and no significant difference within or between devices. The proposed device has the potential to provide cost-effective, rapid, on-site testing within forensic or clinical settings and therefore has wide global applicability.