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Item Mine water and the environment: History until volume 40 and the new cover design(Springer, 2021-07-14) Wolkersdorfer, ChristianThis year, IMWA’s journal Mine Water and the Environment is celebrating its 40th volume, and by the end of 2021, more than 1000 articles will have been published in this journal (author and article index on www. IMWA. info/ author index and www. IMWA. info/ artic les). A total of 2299 authors contributed to these articles, ranging from Abaci et al. (1992) to Żurek et al. (2018). It is a long history of ups and downs, which started with the journal’s first issue in March 1982 (Fig. 1); at that time, the journal’s title was the International Journal of Mine Water (www. IMWA. info/ 40th- anniversary- volume. html). It was initiated by the founding fathers of IMWA and the first Editor-in-Chiefs were Raghu Singh and Rafael Fernández Rubio (Wolkersdorfer 2002). From this year, until April 2000, it was self-published by the association. Between 1982 and 2000, issues of the journal were printed in Granada, Madrid, Budapest, Nottingham, Castro Verde, Wollongong, Denver, and Loveland. During that time, IMWA often did not have enough manuscripts; therefore, volumes 8, 15, and 16 never appeared in print. One of the reasons for this is that IMWA didn’t have many members at that time, and the journal was not as well-known as it is today. That situation changed substantially when the current Editor, Bob Kleinmann, became Editor-in-Chief during the Bled/Slovenia IMWA Congress in 1997. He was able to attract new authors to the journal, so that the journal could be published regularly and changed its name to Mine Water and the Environment. Still, the journal was mainly known primarily by the IMWA family, until the newly appointed IMWA councillor, Christian Wolkersdorfer, got in contact with the international publisher Springer (now Springer Nature) in 1999. During the Katowice, Poland Congress, Christian Witschel from Springer Heidelberg informed the IMWA EC about the details of the publishing process. This resulted in some long nights, where the Editor-in-Chief and the Technical Editor learned how to format the papers using MS Word to meet the Springer layout criteria. Eventually, this meeting resulted in a professional relationship between IMWA and Springer, with the first issue published in Berlin in December 2000.Item Synthesis and application of choline chloride based deep eutectic solvents in liquidliquid and solid-liquid assisted extraction of organophosphorus flame retardants from landfill leachate and sediment.(Taylor and Francis, 2022-09-15) Sibiya, Innocentia Velaphi; Daso, Adegbenro Peter; Okonkwo, Okechukwu JonathanThe extraction of organic pollutants from environmental samples using green solvents has received a lot of interest recently. Simply said, this is due to their extremely low toxicity and volatility when compared to the common organic solvents. Therefore, many extraction exercises now include ionic solvents, as well as the more current deep eutectic solvents (DES). Hence, the current study reports on 1) the synthesis and characterisation of choline chloride/oxalic acid (1:1) and choline chloride/urea (1:2) deep eutectic solvents and 2) their application in liquid-liquid and solid liquid assisted extraction of 14 targeted OPFRs from landfill leachate and sediment samples. The densities, refractive indices and melting points of the DES measured were 1.11 ± 0.15 g/mL, 1.14 ± 0.10 g/mL; 1.50 ± 0.12, 1.45 ± 0.20; and 12 ± 0.05°C, 35 ± 0.06–55 ± 0.05°C for choline chloride/urea (1:2) and choline chloride/oxalic acid (1:1) respectively. Choline chloride/urea (1:2) and choline chloride/ oxalic acid (1:1) viscosities were 87.0 ± 0.20 kg·m −1·s −1 and 13.5 ± 0.14 kg·m −1·s −1 respectively. 1H NMR and FTIR confirmed the structures of the two DES. Recoveries using internal standards dTPP, dTBP, dTPrP and 13C18MTPP ranged from 59.9 ± 7.41–103 ± 5.32%; whereas the percent recoveries using CRM ranged from 85.7–117%. In the leachate (510–1433 ng/L) and sediment (725– 1224 ng/g dw) samples from each landfill, 14 and 13 targeted OPFRs, respectively, were detected. The high recoveries and extraction of OPFRs demonstrated by the two DES imply that these could replace conventional organic solvents used to extract OPFRs from environmental media.Item Comparison of the extractability of organophosphorus flame retardants in landfill media using organic and green solvents.(Springer Nature, 2022-06-09) Sibiya, Velaphi Sibiya; Okonkwo, Okechukwu JonathanOrganic solvents are mainly used in the extraction of organophosphorus flame retardants (OPFRs) because of their availability and having been tested as good extracting solvents for most environmental pollutants. However, organic solvents are toxic, flammable, and costly. Hence, there is an ongoing quest for less hazardous chemicals such as green deep eutectic solvents (DES) that are cheap, recyclable, non-toxic and degradable in the environment, which can be used to extract organic pollutants such as OPFRs in environmental samples. This study assessed the extractability of OPFRs in municipal landfill leachate and sediment, using organic solvents and DES. Of the fourteen targeted OPFRs, 11 (80%) and 7 (50%) were detected in the leachate and sediment samples, using hexane; whereas 14 (100%) and 13 (90%) OPFRs were detected in the same order of samples using DES. The concentrations of OPFRs obtained for the leachate using optimum organic and DES ranged from below the limit of quantification (< LOQ)—516 ± 8.10 ng/L and < LOQ—453 ± 8.10 ng/L respectively. Correspondingly, the concentrations of OPFRs in sediment samples ranged from < LOQ—135 ± 2.89 ng/g dw and < LOQ—395 ± 2.24 ng/g dw, respectively. The results from this study, therefore, highlight the potential of DES to extract more OPFR from complex matrices such as landfill leachate and sediment. This finding infers that green hydrophilic DES can serve as good replacement for organic solvents such as hexane in liquid–liquid extraction (LLE) and solid–liquid extraction (SLE) techniques for landfill leachate and sediment.Item Polybrominated diphenyl ethers in the grey-headed gull (Larus cirrocephalus) and African sacred ibis (Threskiornis aethiopicus).(Royal Society of Chemistry, 2023-08-19) Emereole, C.; Jansen , R.; Okonkwo, O.J.PBDEs have been studied in different types of birds from varying ecosystems, however, few of the studies have focused particularly on scavenger birds. It is important to study these birds since many scavenging birds forage on sites close to human population. The present study investigated PBDE concentrations in the grey-headed gull (Larus cirrocephalus) and African sacred ibis (Threskiornis aethiopicus) scavenging on a landfill site in Pretoria, South Africa. The detection frequencies of PBDEs in soil, leachate and feather samples ranged from nd to 100%, with the higher PBDE congeners generally displaying higher detection frequencies. Soil samples indicated 100% detection frequency for all the congeners, while the detection frequencies of PBDEs in leachate samples ranged from “not detected” for BDE-209 to 100% for BDE-28 and -183. In the feathers of grey-headed gulls and sacred ibises, seven of the eight PBDEs investigated were detected at high frequencies, 87.5–100% and 28–100% respectively. The mean PBDE concentrations detected in soil samples ranged from 1.23 ng g−1 for BDE-183 to 5.12 ng g−1 for BDE-209. The 45–150 mm particle size fraction yielded higher concentrations of PBDEs than the coarser 250–500 mm fraction. The concentrations of PBDEs in the leachate samples ranged from 0.49 g L−1 for BDE-153 to 1.68 g L−1 for BDE-100. The dominant congeners were BDE-47, -100 and -183, while the least dominant congener was BDE-153. The grey-headed gull had P7BDE 47, 99, 100, 153, 154, 183 and 209 ranging in total from 44.40 to 143.45 ng g−1 (median = 95.10 ng g−1). The P7PBDEs for the African sacred ibis ranged from 70.31 to 608.41 ng g−1 (median = 179.08 ng g−1). Spearman's correlation test revealed no significant relationship between beak length and pollutant burden in L. cirrocephalus feathers, suggesting that pollutant accumulation is not a function of age for these birds. Pearson correlation analysis was carried out for P7 PBDEs versus leachate (r = 0.65), soil (r = 0.52) and feather (r = 0.77) with a statistical significance of p < 0.05. The observed positive correlation may suggest a possible influence of leachate and soil on PBDE concentrations in the feathers. These findings indicated high PBDE concentrations in comparison with similar studies carried out in other parts of the world. This suggested that the avian species investigated in this study may be impacted as a result of PBDE contamination, which may also have similar negative effects on other wildlife and human populations that are exposed to the Ondestepoort landfill.Item Organochlorine pesticides and polychlorinated biphenyls in city drains in Makurdi, central Nigeria: Seasonal variations, source apportionment and risk assessment.(Elsevier Ltd., 2023-03-01) Tongu, Sylvester M.; Sha’Ato, Rufus; Wase, Geoffrey A.; Okonkwo, Jonathan O.; Vesuwe, Rebecca N.A study of seasonal variation, sources and potential risks of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in open city drains in Makurdi, Central Nigeria was carried out. OCPs and PCBs were quantified using gas chromatograph-mass spectrometer. The total (Σ 8OCPs) (ngL 1) of OCPs in water was 2.99 with a mean ± SD of 0.75 ± 0.12 during wet season, while during dry season, the values were 11.43 and 2.86 ± 1.54 respectively. In sediment, the total concentration (ngg 1) of OCPs was 5270.66 with a mean ± SD of 1756.89 ± 450.01 during wet season and a total concentration of 5837.93 and the mean ± SD of 1945.98 ± 646.04, during dry season. Source apportionment of OCPs suggested historic application of the pollutants. The total (Σ 7PCBs) concentration (ngL 1) of PCBs in water was 0.24 with a mean ± SD of 0.03 ± 0.02 during wet season and a total concentration of 0.61 with a mean ± SD of 0.09 ± 0.11 during dry season. The total concentration (ngg 1) of PCBs in sediment was 37.88, mean ± SD of 5.41 ± 5.93 during wet season and a total of 47.07 and mean ± SD of 6.72 ± 7.27 during dry season. Ecological risk assessment based on effect range low (ERL) and effect range median (ERM) or threshold effect level (TEL) and probable effect level (PEL) that ecological risks were possible for some OCPs in this study, which calls for source control and remediation of the affected sites. Toxicity equivalency (TEQ) of PCB-118, the dioxin-like congener, indicated that it was most harmful to humans/mammals followed by birds, then fish.Item Neutralisation of acid effluent from steel manufacturing industry and removal of metals using an integrated electric arc furnace dust slag/lime process.(Springer, 2019-11-07) Forsido, Tedlaye; McCrindle, Rob; Maree, Jannie; Mpenyana‑Monyatsi, LizzyIn this study, an integrated electric arc furnace (EAF) dust slag/lime (Ca (OH)2) treatment method was used to treat acid effluent generated by the same stainless-steel producer. EAF slag alone was able to raise the pH to 8.7; thereafter, lime was added to increase the pH to the target pH of 12. The test proved that EAF dust slag, in conjunction with lime, can be used for neutralisation of acid effluent from a steel industry and for the removal of metals Co, Cr, Fe, Ni and Zn. The target metals were removed from the effluent, achieving greater than 99.6% removal. The process was simple and involves only mechanical mixing of the two constituents. Hence, it can be regarded as economically advantageous and environmental friendly since it only utilises a material considered as waste and a small quantity of lime. In addition to being a cost-effective replacement for expensive chemicals used in wastewater treatments, this method can alleviate the problem associated with the disposal of slag, a solid waste generated by a steel manufacturing industry.Item Hot days are associated with short-term adrenocortical responses in a southern African arid-zone passerine bird.(The Company of Biologists, 2021-03-09) Moagi, Lesedi L.; Bourne, Amanda R.; Cunningham, Susan J.; Jansen, Raymond; Ngcamphalala, Celiwe A.; Ganswindt, André; Ridley, Amanda R.; McKechnie, Andrew E.Relatively little effort has been directed towards elucidating the role of physiological stress pathways in mediating avian responses to global heating. For free-ranging southern pied babblers, Turdoides bicolor, daily maximum air temperatures (Tmax) between ∼35 and ∼40°C result in reduced foraging efficiency, loss of body mass and compromised breeding success. We tested the hypothesis that very hot days are experienced as stressors by quantifying relationships between Tmax and faecal glucocorticoid metabolite (fGCM) levels in naturally excreted droppings. On days when Tmax<38°C, fGCM levels were independent of Tmax (mean±s.d. 140.25±56.92 ng g−1 dry mass). At Tmax>38°C, however, fGCM levels increased linearly with Tmax and averaged 190.79±70.13 ng g−1 dry mass. The effects of Tmax on fGCM levels did not carry over to the following morning, suggesting that very hot days are experienced as acute stressors.Item Gastrointestinal nematodes in two galliform birds from South Africa: Patterns associated with host sex and age.(Springer, 2021-06-16) Junker, Kerstin; Spickett, Andrea; Davies, Owen R.; Jansen, Raymond; Krasnov, Boris R.Parasite ecology has recently focused on elucidating patterns and processes that shape helminth communities in avian hosts. However, helminths parasitizing gamebirds are still poorly understood. Here we describe the gastrointestinal nematode fauna of Swainson’s spurfowl, Pternistis swainsonii (Phasianidae) and helmeted guineafowl, Numida meleagris (Numididae), collected at three and four localities, respectively, in South Africa and analyze the prevalence, mean abundance and diversity of their helminth communities. Eleven nematode species were collected from spurfowl, which had a mean number of nematode species per host of 3.01 ± 0.18, whereas guineafowl harboured 15 nematode species, with a mean number of nematode species per host of 3.93 ± 0.12. Focusing on the most prevalent species, we also asked if host sex and/or age were associated with infracommunity structure with regard to nematode counts and species richness, as well as the species and taxonomic composition of infracommunities. While pooling data of nematode species masked the influence of host characteristics on helminth communities, analysis of individual nematode species revealed a number of patterns. In particular, adult female bias was seen in Tetrameres swainsonii in spurfowl and in Allodapa dentigera and Gongylonema congolense in guineafowl; Acuaria gruveli reached higher numbers in adult spurfowl than in juveniles, and helminth infra communities in juvenile male guineafowl were more species rich than those in adult males. Combined, our results suggest that helminth communities of spurfowl and guineafowl are associated with a complex interplay of numerous factors, including host characteristics, parasite traits and environmental conditions.Item Guidance for first responders on the short-term care of confiscated pangolins.(IUCN SSC Pangolin Specialist Group, 2021-12-01) Jansen, Ray; Willis, Jasmin; Waterman, Carly; Challender, DanThis primarily occurs within Asia and Africa, and from Africa to Asia2, but also involves Europe, North America, and other parts of the world. Trade can involve live and dead pangolins, their scales, and other body parts (e.g., skins). Live pangolins are commonly confiscated by local, regional or national law enforcement authorities in Asia and Africa, and many are in ill health because of poor treatment in the illegal trade3. Trafficking takes place despite legislation prohibiting the harvest of pangolins in most countries where pangolins are found and a ban on the commercial, international trade in wild-caught pangolins, which applies to all eight species. Part 1 of this guide is for first responders to instances of trafficking involving live pangolins, including police and customs officers, and other law enforcement agents.Item A global review identifies agriculture as the main threat to declining grassland birds.(Wiley, 2023-05-09) Douglas, David J.T.; Waldinger, Jessica; Buckmire, Zoya; Gibb, Kathryn; Medina, Juan P.; Sutcliffe, Lee; Beckmann, Christa; Collar, Nigel J.; Jansen, Raymond; Kamp, Johannes; Little, Ian; Sheldon, Rob; Yanosky, Alberto; Koper, NicolaGrasslands are globally threatened and their biodiversity, including grassland birds, is declining markedly. To inform grassland bird conservation globally, we systematically reviewed threats and conservation actions for grassland birds, extracting data from 528 papers. Across the 10 primary grassland regions of the globe, agriculture was the most frequently or joint most frequently reported threat in nine regions (reported as a threat in 73% of publications); hunting was the most frequently reported threat in the remaining region. Natural system modifications (reported as a threat in 32% of publications) and climate change and severe weather (24%) were less frequently reported threats compared with agriculture. The types of threat from agriculture varied regionally, but the most pervasive were livestock farming and ranching (reported in 58% of publications where agriculture was a primary threat) and non-timber cropping (43%). Most agricultural threats relate to intensification, but agricultural abandonment, typically the cessation of grazing, sometimes accompanied by tree planting/succession, poses an emerging threat to some grassland birds (reported in 32% of publications where agriculture was a primary threat). The most frequent conservation actions implemented to date include land/water management and protection, and species-specific management actions. Authors of reviewed publications in almost all regions recommend more land/water management, followed by calls for further land/water protection. The parlous state of grassland birds globally suggests that existing conservation actions for grasslands are inadequate. Furthermore, our review suggests that these should be primarily targeted at reversing the negative impacts of agriculture, in particular livestock farming and cropping.Item Polymeric nanocomposite materials for photocatalytic detoxification of polycyclic aromatic hydrocarbons in aquatic environments-A review.(Elsevier B.V., 2022-07-01) Munyengabe, Alexis; Ndibewu, Peter Papoh; Sibali, Linda Lunga; Ngobeni, PrincePolycyclic aromatic hydrocarbons (PAHs) are a known class of persistent and ubiquitous contaminants not only found in sediments but also associated with coastal areas and waters of urbanized estuaries. Due to their hydrophobic nature, PAHs tend to accumulate in the aquatic sediments, leading to bioaccumulation and elevated concentrations over time which is of global concern owing to the serious health risks that they pose to both humans and aquatic life. However, this review highlights various polymeric nanocomposite materials (PNMs) used for the photocatalytic degradation and mechanism of PAHs in aquatic sediments and associated water bodies. It presents the current progress made in the understanding of the toxicological effects of PAHs and mechanisms of their detoxification using photocatalytic processes as an alternative green method for environmental pollution, remediation and control. The paper also provides a brief account of the chemistry, origin and photocatalytic transformation of PAHs, highlighting their bioaccumulation in aquatic sediments and marine environments. It finally accentuates the significance of PNMs as a plausible candidate for the effective treatment of PAHs-contaminated aquatic environments. The available literature reveals that a small number of PNMs has been used to photodegrade PAHs in industrial effluents, seawater, aqueous solution and synthetic wastewater samples. Anthracene, phenanthrene, 2-naphthol and naphthalene as low molecular weight -PAHs were photodegraded using these PNMs under natural light. The findings also show that only chitosan- and graphene oxide based PNMs have been employed to photodegrade these kinds of PAHs in water matrices. Most of the PNMs found in the literature were based on the iron oxide or magnetite incorporation which generates reactive oxygen species via AOPs. Another finding was no study was conducted on the photodegradation of PAHs in soil and sediments which are their main sink in the environment.Item The effect of air supply on nitrogen removal using a biological filter proposed for ventilated pit latrines.(2011-04-21) Coetzee, Martha A.A.; Roux-Van der Merwe, Magaretha P.; Badenhorst, JacquelinePit latrines are the most commonly used sanitation systems in many developing countries. Various researchers have reported elevated nitrate concentrations in groundwater in the vicinity of pit latrines and this could pose a serious health risk to the users of the water source. Faecal sludge from pit latrines contains high concentrations of nitrogen and organic matter (3-5 g∙ℓ−1 N and 20-50 g∙ℓ−1 COD); however, it is produced at a very low rate (1.5 ℓ∙capita−1∙d−1) relative to that of waterborne sewage systems. A pit latrine basically only confines the waste, and no real treatment takes place. In this research the nitrogen was removed in a biological filter using a combination of nitrification and denitrification processes. The aim of this investigation was to determine the effect of air supplied at different rates, namely, 0, 0.3, 1.0 and 2.0 m3∙h−1 N, on the biological filtration process. The application rate was 0.04 m3∙m−2∙d−1. More than 90% removal of nitrogen was observed at an air supply rate of 1.0 m3∙h−1 N. At lower air supply rates nitrification was not complete. At an air supply rate of 2.0 m3∙h−1 nitrogen removal was also approx. 90%, but the biological filter only became stable after about 2 months of operation, possibly due to desiccation of the biomass.Item Physicochemical characterization of maize tassel as an adsorbent. I. Surface texture, microstructure, and thermal stability(Wiley InterScience, 2008-08-09) Zvinowanda, Caliphs M.; Okonkwo, Jonathan O.; Agyei, Nana M.; Shabalala, Pride N.In this study, various physicochemical parameters were evaluated for maize tassel, a novel adsorbent. The Brunauer–Emmett–Teller (BET) isotherm was used to experimentally model N2-adsorption data (up to a relative pressure of 0.30); the results indicated that the powdered material was mesoporous with a BET specific surface area, total volume (up to a relative pressure of 0.98), and average pore width (4V/A by BET) of 2.52 m2/g, 0.0045 cm3/g, and 7.2 nm, respectively, for the 150–300-lm fraction. Laser diffraction pattern analysis yielded particle size distributions for the 45–50-, 50–150-, and 150–300-lm fractions. High-resolution scanning electron microscopy revealed a microstructure showing predominantly flattish, rodlike particles. The material exhibited stability to thermal decomposition up to about 230C, as evidenced by the results obtained from simultaneous thermogravimetry/differential thermal analysis and differential scanning calorimetry.