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Corpse decomposition increases the diversity and abundance of antibiotic resistance genes in different soil types in a fish model
2021
Feng, Tianshu | Su, Wanghong | Zhu, Jianxiao | Yang, Jiawei | Wang, Yijie | Zhou, Rui | Yu, Qiaoling | Li, Huan
As a common natural phenomenon, corpse decomposition may lead to serious environmental pollution such as nitrogen pollution. However, less is known about antibiotic resistance genes (ARGs), an emerging contaminant, during corpse degradation. Here, ARGs and microbiome in three soil types (black, red and yellow soil) have been investigated between experimental and control groups based on next-generation sequencing and high-throughput quantitative PCR techniques. We found that the absolute abundance of total ARGs and mobile genetic elements (MGEs) in the experimental groups were respectively enriched 536.96 and 240.60 times in different soil types, and the number of ARGs in experimental groups was 7–25 more than that in control groups. For experimental groups, the distribution of ARGs was distinct in different soil types, but sulfonamide resistance genes were always enriched. Corpse decomposition was a primary determinant for ARGs profiles. Microbiome, NH₄⁺ concentrates and pH also significantly affected ARGs profiles. Nevertheless, soil types had few effects on ARGs. For soil microbiome, some genera were elevated in experimental groups such as the Ignatzschineria and Myroides. The alpha diversity is decreased in experimental groups and microbial community structures are different between treatments. Additionally, the Escherichia and Neisseria were potential pathogens elevated in experimental groups. Network analysis indicated that most of ARGs like sulfonamide and multidrug resistance genes presented strong positively correlations with NH₄⁺ concentrates and pH, and some genera like Ignatzschineria and Dysgonomonas were positively correlated with several ARGs such as aminoglycoside and sulfonamide resistance genes. Our study reveals a law of ARGs’ enrichment markedly during corpse decomposing in different soil types, and these ARGs contaminant maintaining in environment may pose a potential threat to environmental safety and human health.
Show more [+] Less [-]Urinary triclosan in south China adults and implications for human exposure
2021
Yang, Dongfeng | Kong, Sifang | Wang, Feng | Tse, Lap Ah | Tang, Zhi | Zhao, Yang | Li, Chun | Li, Minhui | Li, Zihan | Lu, Shaoyou
Triclosan (TCS) is widely applied in personal care products (PCPs) as an antimicrobial preservative. Due to its toxicity and potential risk to human health, TCS has attracted mounting concerns in recent years. However, biomonitoring of TCS in large human populations remains limited in China. In this study, 1163 adults in South China were recruited and urinary TCS concentrations were determined. TCS was detected in 99.5% of urine samples, indicating broad exposure in the study population. Urinary concentrations of TCS ranged from below the limit of detection (LOD) to 270 μg/L, with a median value of 3.67 μg/L. Urinary TCS concentrations from individuals were all lower than the Biomonitoring Equivalents reference dose, suggesting relatively low health risk in the participants. TCS concentrations did not differ significantly between sexes or education levels (p > 0.05). Nevertheless, marital status and age were found to be positively influence TCS levels (p < 0.001). After adjustment for body mass index (BMI), age was determined to be positively associated with TCS concentrations (p < 0.05), particularly in the age group from 31 to 51 years old. This study provides a baseline of urinary TCS exposure in South China general adult populations.
Show more [+] Less [-]Coastal observation of halocarbons in the Yellow Sea and East China Sea during winter: Spatial distribution and influence of different factors on the enzyme-mediated reactions
2021
Zou, Yawen | He, Zhen | Liu, Junying | Qi, Qianqian | Yang, Gui-Peng | Mao, Shihai
Volatile brominated compounds are important trace gases for stratospheric ozone chemistry. In this study, the spatial variations of dibromomethane (CH₂Br₂), bromodichloromethane (CHBrCl₂), dibromochloromethane (CHBr₂Cl) and bromoform (CHBr₃) in the seawater and overlying atmosphere were measured in the Yellow Sea (YS) and the East China Sea (ECS) in winter. The air-sea fluxes of CH₂Br₂, CHBrCl₂, CHBr₂Cl and CHBr₃ ranged from −11.46 to 25.33, −4.68 to 7.91, −8.60 to 4.08 and −88.57 to 8.84 nmol m⁻²·d⁻¹, respectively. In order to understand the mechanism of halocarbons production, we measured bromoperoxidase (BrPO) activity (39.18–186.74 μU·L⁻¹) in the YS and ECS for the first time using an aminophenyl fluorescein (APF) method and performed in-situ incubation experiments in BrPO-treated seawater. The production rates of CH₂Br₂, CHBrCl₂, CHBr₂Cl and CHBr₃ ranged from 14.21 to 94.74, 0.00 to 19.74, 0.00 to 30.62 and 6.18–72.75 pmol L⁻¹·h⁻¹, respectively, in BrPO-treated seawater. There were significantly higher production rates in coastal waters compared with the open sea (P = 0.016) because of higher DOC levels near the coast. Moreover, the production rates of halocarbons increased with BrPO activity and H₂O₂ concentration. The results showed that enzyme-mediated reaction was an important source for the production of halocarbons in seawater. The present research is of great significance for understanding the production mechanisms of halocarbons in seawater and global oceanic halocarbons emissions.
Show more [+] Less [-]Biomonitoring of 89 POPs in blood serum samples of Czech city policemen
2021
Polachova, Andrea | Gramblicka, Tomas | Bechynska, Kamila | Parizek, Ondrej | Parizkova, Denisa | Dvorakova, Darina | Honkova, Katerina | Rossnerova, Andrea | Rossner, Pavel | Sram, Radim J. | Topinka, Jan | Pulkrabova, Jana
In this biomonitoring study, we evaluated the concentrations of 8 polychlorinated biphenyls (PCBs), 11 organochlorinated pesticides (OCPs), 33 brominated flame retardants (BFRs), 7 novel brominated and chlorinated flame retardants (novel FRs) and 30 per- and polyfluoroalkylated substances (PFAS) in human serum samples (n = 274). A total of 89 persistent organic pollutants (POPs) were measured in blood serum samples of city policemen living in three large cities and their adjacent areas (Ostrava, Prague, and Ceske Budejovice) in the Czech Republic. All samples were collected during the year 2019 in two sampling periods (spring and autumn). The identification/quantification of PCBs, OCPs, BFRs, novel FRs and PFAS was performed by means of gas chromatography coupled to (tandem) mass spectrometry (GC–MS/(MS)) and ultra-high performance liquid chromatography coupled to triple quadrupole tandem mass spectrometry (UHPLC–MS/MS). The most frequently detected pollutants were perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluorooctanesulfonate (PFOS), perfluorohexanesulfonate (PFHxS), 2,2′,3,4,4′,5′-hexachlorobiphenyl (CB 138), 2,2′,4,4′,5,5′-hexachlorobiphenyl (CB 153), 2,2′,3,3′,4,4′,5-heptachlorobiphenyl (CB 170), 2,2′,3,4,4′,5,5′-heptachlorobiphenyl (CB 180), hexachlorobenzene (HCB), and p,p'-dichlorodiphenyldichloroethylene (p,p′-DDE) quantified in 100% of serum samples. In the serum samples, the concentrations of determined POPs were in the range of 0.108–900 ng g⁻¹ lipid weight (lw) for PCBs, 0.106–1016 ng g⁻¹ lw for OCPs, <0.1–618 ng g⁻¹ lw for FRs and <0.01–18.3 ng mL⁻¹ for PFAS, respectively. Locality, sampling season, and age were significantly associated with several POP concentrations. One of the important conclusions was that within the spring sampling period, statistically significant higher concentrations of CB 170 and CB 180 were observed in the samples from Ostrava (industrial area) compared to Prague and Ceske Budejovice. Older policemen had higher concentrations of five PCBs and two OCPs in blood serum.
Show more [+] Less [-]Variations in nitrogen removal rates and microbial communities over sediment depth in Daya Bay, China
2021
Wu, Jiapeng | Hong, Yiguo | Liu, Xiaohan | Hu, Yaohao
Depth-related variations in the activities, abundances, and community composition of denitrification and anaerobic ammonia oxidation (anammox) bacteria in coastal sediment cores remain poorly understood. In this study, we used ¹⁵N-labelled incubation, quantitative polymerase chain reaction (qPCR), and high-throughput sequencing techniques to reveal the structure and function of denitrifiers and anammox bacteria in sediment cores (almost 100 cm depth) collected in winter and summer from four locations in Daya Bay. The results indicated that the activities and abundances of both denitrifiers and anammox bacteria were detected even in deeper sediments with low concentrations of dissolved inorganic nitrogen (DIN). The potential rates, abundances, and community compositions of denitrifiers and anammox bacteria only varied spatially. In the surface sediment (top 2 cm), denitrifiers had significantly higher activities and abundances than anammox bacteria, but the relative contribution of anammox bacteria to nitrogen loss increased to >60% in the subsurface sediments. Phylogenetic analysis revealed that nirS-type denitrifiers were affiliated to 10 different clusters and Candidatus Scalindua dominated the anammox community in the whole sediments. Furthermore, both denitrification and anammox bacterial communities in the subsurface sediments were distinct from those in the surface sediments. Coupled nitrification and denitrification or anammox may play significant roles in removing fixed N, and the availability of electronic acceptors (e.g. nitrite and nitrate) strongly influenced the N loss activities in the subsurface sediment, emphasising its role as a sink for buried N.
Show more [+] Less [-]Interactions and effects of microplastics with heavy metals in aquatic and terrestrial environments
2021
Khalid, Noreen | Aqeel, Muhammad | Noman, Ali | Khan, Shujaul Mulk | Akhter, Noreen
Contamination of waters and soils with microplastics (MPs) is an emerging environmental issue worldwide. MPs constitute a cocktail of various additives and polymers besides adsorbing toxic heavy metals from the environment. This co-occurrence of MPs with heavy metals poses a threat to the health of organisms and is poorly understood. Ingestion of MPs contaminated with heavy metals may also result in subsequent transfer of heavy metals up in the food chain. MPs surfaces play a crucial role in the adsorption of heavy metals. Aged/biofouled MPs facilitate greater adsorption of metals and certain microplastic (MP) polymers adsorb some metals more specifically. External factors involved in the process of adsorption/accumulation of heavy metals are the solution pH, salinity, and the concentration of relevant heavy metals in the media. Desorption greatly depends upon pH of the external solution. This is more concerning as the guts/digestive systems of organisms have low pH which could enhance the desorption of toxic metals and making them accumulate in their bodies. The aim of this article is to discuss the abundance, distribution, adsorption, and desorption behavior of MPs for heavy metals, and their combined toxic effects on flora and fauna based on the limited research on this topic in the literature. There is an overarching need to understand the interactions of MPs with heavy metals in different ecosystems so that the extent of ecotoxic effects they pose could be assessed which would help in the environmental regulation of these pollutants.
Show more [+] Less [-]Noisy waters can influence young-of-year lobsters’ substrate choice and their antipredatory responses
2021
Leiva, Laura | Scholz, Sören | Giménez, Luis | Boersma, M. (Maarten) | Torres, Gabriela | Krone, Roland | Tremblay, Nelly
Offshore human activities lead to increasing amounts of underwater noise in coastal and shelf environments, which may affect commercially-important benthic invertebrate groups like the re-stocked Helgoland European lobster (Homarus gammarus) in the German Bight (North Sea). It is crucial to understand the impact tonal low-frequency noises, like maritime transport and offshore energy operations, may have on substrate choice and lobsters' behavior to assess potential benefits or bottlenecks of new hard-substrate artificial offshore environments that become available. In this study, we investigated the full factorial effect of a tonal low-frequency noise and predator presence on young-of-year (YOY) European lobsters' in a diurnal and nocturnal experiment. Rocks and European oyster shells (Ostrea edulis) were offered as substrate to YOY lobsters for 3 h. Video recordings (n = 134) allowed the identification of lobsters' initial substrate choice, diel activity and key behaviors (peeking, shelter construction, exploration and hiding). To ensure independence, YOY lobsters in the intermolt stage were randomly selected and assigned to the experimental tanks and used only once. We provide the first evidence that stressors alone, and in combination, constrain YOY lobsters' initial substrate choice towards rocks. During nighttime, the joint effect of exposure to a constant low-frequency noise and predator presence decreased antipredator behavior (i.e., hiding) and increased exploration behavior. Noise may thus interfere with YOY lobsters' attention and decision-making processes. This outcome pinpoints that added tonal low-frequency noise in the environment have the potential to influence the behavior of early-life stages of European lobsters under predator pressure and highlights the importance of including key benthic invertebrates' community relationships in anthropogenic noise risk assessments. Among others, effects of noise must be taken into consideration in plans involving the multi-use of any offshore area for decapods’ stock enhancement, aquaculture, and temporary no-take zones.
Show more [+] Less [-]Blood, urine and semen Volatile Organic Compound (VOC) pattern analysis for assessing health environmental impact in highly polluted areas in Italy
2021
Longo, Valentina | Forleo, Angiola | Ferramosca, Alessandra | Notari, Tiziana | Pappalardo, Sebastiana | Siciliano, P. (Pietro) | Capone, Simonetta | Montano, Luigi
Volatile Organic Compound (VOC) analysis is usually applied in pollution assessment by checking for toxic or harmful volatile compounds in air, water and soil samples. In this study, exogenous VOCs and their derivatives, metabolized by cells, were valued into specific body fluids. In particular, the VOC profiles of blood, urine and human semen samples collected from young men living in two high pollution areas in Italy, i.e. Land of Fires and Valley of Sacco River, were fingerprinted. The analysis is based on Headspace Solid Phase MicroExtraction (HS-SPME) followed by Gas Chromatography-Mass Spectrometric detection (GC-MS). The volatile composition of the three body fluids showed that some VOCs are in common between blood, urine and human semen samples, whereas others are present only in a body fluid. Some compounds, as well as also some chemical classes show a higher affinity for a specific body fluid. Statistical analysis allowed to discriminate the two contaminated areas and identify those compounds which significantly contribute to the two areas classification. Some of these compounds are toxic and found prevalently in Valley of Sacco River samples, correspondingly to sperm analysis results for young men living in this zona worse than those living in Land of Fires.
Show more [+] Less [-]Associations between air pollutant exposure and renal function: A prospective study of older adults without chronic kidney disease
2021
Li, Ang | Mei, Yayuan | Zhao, Meiduo | Xu, Jing | Li, Runkui | Zhao, Jiaxin | Zhou, Quan | Ge, Xiaoyu | Xu, Qun
We used real-world exposure scenarios to evaluate the effect of six ambient air pollutant (PM₂.₅, PM₁₀, NO₂, SO₂, CO, and O₃) exposure on renal function among older adults without chronic kidney disease (CKD). We recruited 169 older adults without CKD in Beijing, China, for a longitudinal study from 2016 to 2018. The Modification of Diet in Renal Disease (MDRD) and the Chronic Kidney Disease Epidemiology Collaboration (EPI) equations were employed to derive the estimated glomerular filtration rate (eGFR). A linear mixed-effects model with random intercepts for participants was employed to determine the effects of air pollutants on renal function evaluated on the basis of eGFR and urinary albumin/creatinine ratio at different exposure windows (1-, 2-, 3-, 5-, 7-, 14-, 28-, 45-, and 60-days moving averages). An interquartile range (IQR) increase in NO₂ for was associated with significant decreases of in eGFR (MDRD equation) [percentage changes: −4.49 (95% confidence interval: −8.44, −0.37), −5.51 (−10.43, −0.33), −2.26 (−4.38, −0.08), −3.71 (−6.67, −0.65), −5.44 (−9.58, −1.11), −5.50 (−10.24, −0.51), −6.15 (−10.73, −1.33), and −6.34 (−11.17, −1.25) for 1-, 2-, 5-, 7-, 14-, 28-, 45-, and 60-days moving averages, respectively] and in eGFR (EPI equation) [percentage changes: −5.04 (−7.09, −2.94), −6.25 (−8.81, −3.62), −5.16 (−7.34, −2.92), −5.10 (−7.85, −2.28), −5.83 (−8.23, −3.36), −6.04 (−8.55, −3.47) for 1-, 2-, 14-, 28-, 45-, and 60-days moving averages, respectively]. In two-pollutant model, only the association of NO₂ exposure with eGFR remained robust after adjustment for any other pollutant. This association was stronger for individuals with hypertension for the EPI equation or BMI <25 kg/m² for the MDRD equation at lags 1 and 1–2. Our findings suggest that NO₂ exposure is associated with eGFR reduction among older adults without CKD for short (1-, 2-days) and medium (14-, 28-, 45-, 60-days) term exposure periods; thus, NO₂ exposure may contribute to renal impairment.
Show more [+] Less [-]Global greenhouse vegetable production systems are hotspots of soil N2O emissions and nitrogen leaching: A meta-analysis
2021
Qasim, Waqas | Xia, Longlong | Lin, Shan | Wan, Li | Zhao, Yiming | Butterbach-Bahl, Klaus
Vegetable production in greenhouses is often associated with the use of excessive amounts of nitrogen (N) fertilizers, low NUE (15–35%), and high N losses along gaseous and hydrological pathways. In this meta-analysis, we assess the effects of application rate, fertilizer type, irrigation, and soil properties on soil N₂O emissions and nitrogen leaching from greenhouse vegetable systems on the basis of 75 studies. Mean ± standard error (SE) N₂O emissions from unfertilized control plots (N₂Ocₒₙₜᵣₒₗ) and N leaching (NLcₒₙₜᵣₒₗ) of greenhouse vegetable systems were 3.2 ± 0.4 and 91 ± 20 kg N ha⁻¹ yr⁻¹, respectively, indicating legacy effects due to fertilization in preceding crop seasons. Soil organic carbon concentrations (SOC) and irrigation were significantly positively correlated with NLcₒₙₜᵣₒₗ losses, while other soil properties did not significantly affect N₂Ocₒₙₜᵣₒₗ or NLcₒₙₜᵣₒₗ. The annual mean soil N₂O emission from fertilized greenhouse vegetable systems was 12.0 ± 1.0 kg N₂O–N ha⁻¹ yr⁻¹ (global: 0.067 Tg N₂O–N yr⁻¹), with N₂O emissions increasing exponentially with fertilization. The mean EFN₂O was 0.85%. The mean annual nitrogen leaching (NL) was 297 ± 22 kg N ha⁻¹ yr⁻¹ (global: 1.66 Tg N yr⁻¹), with fertilization, irrigation, and SOC explaining 65% of the observed variation. The mean leaching factor across all fertilizer types was 11.9%, but 18.7% for chemical fertilizer. Crop NUE was highest, while N₂O emissions and N leaching were lowest, at fertilizer rates <500 kg N ha⁻¹ year⁻¹. Yield-scaled N₂O emissions (0.05 ± 0.01 kg N₂O–N Mg⁻¹ yr⁻¹) and nitrogen leaching (0.79 ± 0.08 kg N Mg⁻¹ yr⁻¹) were lowest at fertilizer rates <1000 kg N ha⁻¹ yr⁻¹. Vegetables are increasingly produced in greenhouses, often under management schemes of extreme fertilization (>1500 kg N ha⁻¹ yr⁻¹) and irrigation (>1200 mm yr⁻¹). Our study indicates that high environmental N₂O and N leaching losses can be mitigated by reducing fertilization rates to 500–1000 kg N ha⁻¹ yr⁻¹ (mean: ∼762 kg N ha⁻¹ yr⁻¹) without jeopardizing yields.
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