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Presence and fate of veterinary antibiotics in age-dated groundwater in areas with intensive livestock farming
2018
Kivits, Tano | Broers, Hans Peter | Beeltje, Henry | van Vliet, Mariëlle | Griffioen, Jasper
The combination of emerging antibiotic resistance and lack of discovery of new antibiotic classes poses a threat to future human welfare. Antibiotics are administered to livestock at a large scale and these may enter the environment by the spreading of manure on agricultural fields. They may leach to groundwater, especially in the Netherlands which has some of the most intensive livestock farming and corresponding excessive manure spreading in the world. This study investigates the presence of antibiotics in groundwater in two regions with the most intensive livestock farming in the Netherlands. If so, the hydrochemical conditions were further elaborated. Ten multi-level wells with in total 46 filters were sampled, focusing on relatively young, previously age-dated groundwater below agricultural fields. Twenty-two antibiotics were analyzed belonging to the following antibiotic groups: tetracyclines, sulfonamides, trimethoprims, β-lactams, macrolides, lincosamides, quinolones, nitrofurans and chloramphenicol. The samples were analyzed for these antibiotics by LC-MS/MS ESI-POS/NEG (MRM) preceded by solid phase extraction which resulted in importantly low detection limits. Six antibiotics were found above detection limits in 31 filters in seven wells: sulfamethazine, sulfamethoxazole, lincomycin, chloramphenicol, ciprofloxacin, and sulfadiazine. The concentrations range from 0.3 to 18 ng L−1. Sulfonamides were detected at all measured depths down to 23 meters below surface level with apparent groundwater ages up to 40 years old. No antibiotics were detected below the nitrate/iron redox cline, which suggests that the antibiotics might undergo degradation or attenuation under nitrate-reducing redox conditions. This study provides proof that antibiotics are present in groundwater below agricultural areas in the Netherlands due to the spreading of animal manure.
Show more [+] Less [-]Past 140-year environmental record in the northern South China Sea: Evidence from coral skeletal trace metal variations
2014
Song, Yinxian | Yu, Kefu | Zhao, Jianxin | Feng, Yuexing | Shi, Qi | Zhang, Huiling | Ayoko, G. A. (Godwin A.) | Frost, Ray L.
About 140-year changes in the trace metals in Porites coral samples from two locations in the northern South China Sea were investigated. Results of PCA analyses suggest that near the coast, terrestrial input impacted behavior of trace metals by 28.4%, impact of Sea Surface Temperature (SST) was 19.0%, contribution of war and infrastructure were 14.4% and 15.6% respectively. But for a location in the open sea, contribution of War and SST reached 33.2% and 16.5%, while activities of infrastructure and guano exploration reached 13.2% and 14.7%. While the spatiotemporal change model of Cu, Cd and Pb in seawater of the north area of South China Sea during 1986–1997 were reconstructed. It was found that in the sea area Cu and Cd contaminations were distributed near the coast while areas around Sanya, Hainan had high Pb levels because of the well-developed tourism related activities.
Show more [+] Less [-]Reduced nitrogen in ecology and the environment
2007
Erisman, J.W. | Bleeker, A. | Galloway, J. | Sutton, M.S.
Since the beginning of the 19th century humans have increasingly fixed atmospheric nitrogen as ammonia to be used as fertilizer. The fertilizers are necessary to create amino acids and carbohydrates in plants to feed animals and humans. The efficiency with which the fertilizers eventually reach humans is very small: 5-15%, with much of the remainder lost to the environment. The global industrial production of ammonia amounts to 117 Mton NH3-N year-1 (for 2004). By comparison, we calculate that anthropogenic emissions of NH3 to the atmosphere over the lifecycle of industrial NH3 in agriculture are 45.3 Mton NH3-N year-1, about half the industrial production. Once emitted ammonia has a central role in many environmental issues. We expect an increase in fertilizer use through increasing demands for food and biofuels as population increases. Therefore, management of ammonia or abatement is necessary. Half of industrial ammonia production is eventually lost to the global environment with significant effects.
Show more [+] Less [-]Distribution of antibiotic resistance genes from human and animal origins to their receiving environments: A regional scale survey of urban settings
2022
Antibiotic resistance is a growing problem for ecosystem health and public healthcare. Hence, the transmission of antibiotic resistance from human and animal origins to natural environments requires careful investigation. In this study, nine antibiotic resistance genes (ARGs), three mobile genetic elements (MGEs), and their relations with antibiotics, heavy metals, and microbiota were investigated in 16 sample sites (Xinxiang, China). Fluoroquinolones (0.13–14.22 μg/L) were most abundant in hospital effluent and oxytetracycline (251.86–5817.47 μg/kg) in animal manure. Animal manure showed the highest levels of zinc (80.79–2597.14 mg/kg) and copper (32.47–85.22 mg/kg), possibly affecting the prevalence of intI1 and aac(6′)-Ib genes. Aminoglycoside and sulfonamide resistance genes (aac(6’)-Ib, aadA, and sul1) were the main ARGs in this area. In addition, the detected ARGs and MGEs were higher in animal manure than in hospital effluent, except for the sul1 gene. On the other hand, the incomplete removal of antibiotics (29.76–100%), heavy metals (31.25–100%), and ARGs (1–3 orders of magnitude) in MWWTPs resulted in the accumulation of these contaminants in the receiving river. Network analysis suggested that the potential hosts (Jeotgalibaca, Atopostipes, Corynebacterium_1, etc.) of ARGs were more predominant in animal manure rather than hospital effluent, indicating a higher ARG transfer potential in animal manure compared with hospital sources. These results provide useful insights into the different migration and dissemination routes of antibiotics, heavy metals, ARGs, and microbiota from anthropogenic and animal origins to their receiving environments via MWWTP discharge and manure fertilization.
Show more [+] Less [-]Dissemination of blaNDM-5 via IncX3 plasmids in carbapenem-resistant Enterobacteriaceae among humans and in the environment in an intensive vegetable cultivation area in eastern China
2021
Zhao, Qian | Berglund, Björn | Zou, Huiyun | Zhou, Ziyu | Xia, Huiyu | Zhao, Ling | Nilsson, Lennart E. | Li, Xuewen
The environment of a large-scale vegetable production area can be exposed to antibiotic residues and antibiotic-resistant bacteria (ARB) via animal manure and irrigation with contaminated water, which can facilitate the dissemination of ARB. However, the occurrence of ARB in plantation areas and their dissemination in this environment remain largely unexplored. In total, 382 samples including those from vegetable (n = 106), soil (n = 87), well water (n = 24), river water (n = 20), river sediments (n = 20), farmer feces (n = 58) and farmer hands (n = 67) were collected in 2019 from a large-scale cultivation area in Shandong, China. Selective agar plates were used to screen for carbapenem-resistant Enterobacteriaceae (CRE) and whole-genome sequencing and Southern blotting were used to characterise isolates and mobile genetic elements carrying carbapenem resistance determinants. A total of nine NDM-5-producing isolates of Escherichia coli, Klebsiella pneumoniae, and Citrobacter spp. were identified from environmental sources and human feces, all of which were multidrug-resistant. Single nucleotide polymorphism analysis suggested clonal transmission of carbapenem-resistant Citrobacter sedlakii within greenhouse soils in the area. Eight of the isolates carried closely related or identical IncX3 plasmids carrying blaNDM₋₅, which were shown to be conjugative via filter mating experiments, indicating the highly transmissible nature of this genetic element. Isolates of E. coli and Citrobacter freundii were detected in the feces of local farm workers and contained similar IncX3 plasmids with blaNDM₋₅ environmental isolates, suggesting a potential risk of CRE transfer from the work environment to the farm workers. Thus, further research is required to investigate the potential health risks associated with environmental exposure to CRE in vegetable cultivation areas.
Show more [+] Less [-]Seabird breeding islands as sinks for marine plastic debris
2021
Grant, Megan L. | Lavers, Jennifer L. | Hutton, Ian | Bond, Alexander L.
Seabirds are apex predators in the marine environment and well-known ecosystem engineers, capable of changing their terrestrial habitats by introducing marine-derived nutrients via deposition of guano and other allochthonous inputs. However, with the health of the world’s oceans under threat due to anthropogenic pressures such as organic, inorganic, and physical pollutants, seabirds are depositing these same pollutants wherever they come to land. Using data from 2018 to 2020, we quantify how the Flesh-footed Shearwater (Ardenna carneipes) has inadvertently introduced physical pollutants to their colonies on Lord Howe Island, a UNESCO World Heritage site in the Tasman Sea and their largest breeding colony, through a mix of regurgitated pellet (bolus) deposition and carcasses containing plastic debris. The density of plastics within the shearwater colonies ranged between 1.32 and 3.66 pieces/m² (mean ± SE: 2.18 ± 0.32), and a total of 688,480 (95% CI: 582,409–800,877) pieces are deposited on the island each year. Our research demonstrates that seabirds are a transfer mechanism for marine-derived plastics, reintroducing items back into the terrestrial environment, thus making seabird colonies a sink for plastic debris. This phenomenon is likely occurring in seabird colonies across the globe and will increase in severity as global plastic production and marine plastic pollution accelerates without adequate mitigation strategies.
Show more [+] Less [-]Analysis of the occurrence and molecular characteristics of drug-resistant strains of Enterococcus faecalis isolated from the gastrointestinal tract of insectivorous bat species in Poland: A possible essential impact on the spread of drug resistance?
2021
Nowakiewicz, Aneta | Zięba, Przemysław | Gnat, Sebastian | Osińska, Marcelina | Łagowski, Dominik | Kosior-Korzecka, Urszula | Puzio, Iwona | Król, Jarosław
Bats are poorly understood as a reservoir of multidrug-resistant strains; therefore, the aim of this study was to determine molecular characterization of multidrug-resistant Enterococcus strains isolated from bat species from Poland. A multi-stage analysis based on targeted isolation of drug-resistant strains (selective media with tetracycline, chloramphenicol, gentamicin, streptomycin, and vancomycin), determination of the phenotypic profile of drug-susceptibility using the disc diffusion method, and amplification of DNA fragments surrounding rare restriction sites (ADSRRS-fingerprinting) was used for the isolation and differentiation of strains. The applied strategy finally allowed identification of E. faecalis resistant to at least one antimicrobial in 47.2% of the single-animal group and in 46.9% of the pooled samples of bat’s guano. Out of the 36 distinct isolates, 69% met the criteria of multi-drug resistance, with a dominant combination of resistance to tetracycline, erythromycin, and rifampicin. Simultaneously, 41.6% of the strains were high-level aminoglycoside resistant (HLAR). In most strains, phenotypic resistance was reflected in the presence of at least one gene encoding resistance to a given drug. Moreover, our research results show that some genes were detected simultaneously in the same strain statistically significantly more frequently. This may confirm that the spread of some genes (tetM and ermB or aph (3′)-IIIa as well as gelE and aac (6′)-Ie-aph (2″)-Ia or ant (6)-Ia) is associated with their common occurrence on the same mobile genetic element.To our knowledge, this is the first analysis of multidrug-resistance among E. faecalis isolated from bats. Our research demonstrates that the One Health concept is not associated exclusively with food-producing animals and humans, but other species of wildlife animals should be covered by monitoring programs as well.We confirmed for the first time that bats are an important reservoir of multi-resistant E. faecalis strains and could have a great impact on environmental resistance.
Show more [+] Less [-]Is the urban-adapted ring-billed gull a biovector for flame retardants?
2019
Desjardins, Chloé F. | Mazerolle, Marc J. | Verreault, Jonathan
Birds may act as biovectors of nutrients and contaminants at the regional scale and potentially increase the exposure to such substances in ecosystems frequented by these birds. However, no study has estimated biotransport of contaminants by individual birds through their feces (guano). Elevated concentrations of halogenated flame retardants (HFRs) have been reported in ring-billed gulls (Larus delawarensis) breeding near Montreal (QC, Canada)- a known hotspot for HFRs. The objective of the present study was to investigate the concentrations of polybrominated diphenyl ethers (PBDEs) and selected emerging HFRs (e.g., Dechlorane-related compounds) in guano of individual ring-billed gulls, and to assess the relative accumulation of these HFRs by comparing concentrations in plasma (absorbed) versus guano (excreted). A second objective was to determine the importance of one of the largest ring-billed gull colony (Deslauriers Island) in North America located near Montreal as a vector of HFR biotransport at the regional scale. Elevated concentrations of PBDEs and Dechlorane plus were determined in guano and plasma of ring-billed gulls, although in general no difference was found between males and females. However, plasma to guano concentration ratios were significantly greater in females for the highly hydrophobic BDE-209 and Dechlorane plus compared to males. Overall, for both sexes combined, the total amount of HFRs (sum of the 16 major PBDEs and five emerging HFRs) deposited by this entire colony (64,980 gulls) in the Montreal area through guano during the 28-days incubation period was estimated to 1 g. This study showed that urban-adapted ring-billed gulls from this large colony represent an underestimated biovector of HFRs, which may contribute to augment exposure to these toxic compounds in nearby ecosystems.
Show more [+] Less [-]Dissolved organic carbon from sewage sludge and manure can affect estrogen sorption and mineralization in soils
2010
Stumpe, Britta | Marschner, Bernd
In this study, effects of sewage sludge and manure borne dissolved organic carbon (DOC) on 17β-estradiol (E2) and 17α-ethinylestradiol (EE2) sorption and mineralization processes were investigated in three agricultural soils. Batch equilibrium techniques and equilibrium dialysis methods were used to determine sorption mechanisms between DOC, estrogens and the soil solid phase. It was found that that the presence of organic waste borne DOC decreased estrogen sorption in soils which seems to be controlled by DOC/estrogen complexes in solution and by exchange processes between organic waste derived and soil borne DOC. Incubation studies performed with 14C-estrogens showed that DOC addition decreased estrogen mineralization, probably due to reduced bioavailability of estrogens associated with DOC. This increased persistence combined with higher mobility could increase the risk of estrogen transport to ground and surface waters. The effect of DOC on estrogen sorption and mineralization is influenced by exchange processes between organic waste borne and soil derived DOC.
Show more [+] Less [-]Restriction of sulfate reduction on the bioavailability and toxicity of trace metals in Antarctic lake sediments
2020
Chen, Yuanqing | Ge, Jingwen | Huang, Tao | Shen, Lili | Chu, Zhuding | Xie, Zhouqing
In this study, Acid-Volatile Sulfur (AVS), trace metals Cu, Cd and Zn and their chemical speciation based on BCR-sequential and simultaneous extraction (SEMs) in Antarctic lake sediments (Y2-1 and YO) were analyzed to investigate the restriction of sulfate reduction on the bioavailability and toxicity of trace metals. Much higher trace metals in Y2-1 indicating a primary source from penguin guano. The main chemical speciation of Cu and Cd in Y2-1 was their oxidizable fraction in contrast to those of weak-acid extraction in YO. Lower ratio of ΣSEM/AVS in Y2-1 indicating less toxicity of the trace metals. The main chemical speciation of Cd in Y2-1 was their oxidizable fraction in contrast to that exchangeable fraction in penguin guano, indicating that although amounts of Cd was transported from marine to lake by penguins, strong sulfate reduction in ornithogenic sediments restricts the bioavailability and toxicity of Cd through the formation of insoluble sulfide.
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