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Determinants of the exposure of Eurasian griffon vultures (Gyps fulvus) to fluoroquinolones used in livestock: The role of supplementary feeding stations
2022
Herrero-Villar, Marta | Mateo-Tomás, Patricia | Sánchez-Barbudo, Inés S. | Camarero, Pablo R. | Taggart, Mark A. | Mateo, Rafael
Veterinary pharmaceuticals, including antibiotics, are emerging contaminants of concern worldwide. Avian scavengers are exposed to pharmaceuticals through consumption of livestock carcasses used for feeding wildlife for conservation purposes at supplementary feeding stations. Here we tested the hypothesis that griffon vultures (Gyps fulvus) would be more exposed to antibiotics (i.e., quinolones) when feeding on livestock carcasses from intensive farming than when they rely on carcasses from extensive farming or wild animals. We sampled 657 adult griffon vultures captured between 2008 and 2012. In addition, we sampled tissues from domestic livestock supplied at feeding stations in the study area between 2009 and 2019; pig (n = 114), sheep (n = 28), cow (n = 1) and goat (n = 2). Samples were analysed by liquid chromatography with electrospray ionization mass spectrometry (LC-ESI-MS). Quinolones were detected in plasma from 12.9% of the griffon vultures analysed. Quinolone prevalence in griffon vultures varied significantly among feeding stations but was also affected by the total amount of carcasses supplemented, especially the mass of pig carcasses. These results aligned with a 21.1% quinolone prevalence in pig carcasses sampled at feeding stations, wherein enrofloxacin and ciprofloxacin levels of up to 3359 ng/g and 1550 ng/g, respectively, were found. Given enrofloxacin pharmacokinetics in pig tissues, 5.3% of the analysed pigs may have died no more than one day after treatment. Quinolone presence in vultures was negatively associated with blood lead levels, which mostly originates from lead ammunition and indicates a higher consumption of game animal carcasses. Carcass disposal for feeding avian scavengers must always assess and manage the risks posed by veterinary pharmaceuticals, especially when livestock provided may have died soon after treatment.
Afficher plus [+] Moins [-]Macroalgae metal-biomonitoring in Antarctica: Addressing the consequences of human presence in the white continent
2022
Lavergne, Céline | Celis-Plá, Paula S.M. | Chenu, Audran | Rodríguez-Rojas, Fernanda | Moenne, Fabiola | Díaz, María José | Abello-Flores, María Jesús | Díaz, Patricia | Garrido, Ignacio | Bruning, Paulina | Verdugo, Marcelo | Lobos, M Gabriela | Sáez, Claudio A.
Marine ecosystems in the Arctic and Antarctica were once thought pristine and away from important human influence. Today, it is known that global processes as atmospheric transport, local activities related with scientific research bases, military and touristic maritime traffic, among others, are a potential source of pollutants. Macroalgae have been recognized as reliable metal-biomonitoring organisms due to their accumulation capacity and physiological responses. Metal accumulation (Al, Cd, Cu, Fe, Pb, Zn, Se, and Hg) and photosynthetic parameters (associated with in vivo chlorophyll a fluorescence) were assessed in 77 samples from 13 different macroalgal species (Phaeophyta; Chlorophyta; Rhodophyta) from areas with high human influence, nearby research and sometimes military bases and a control area, King George Island, Antarctic Peninsula. Most metals in macroalgae followed a pattern influenced by rather algal lineage than site, with green seaweeds displaying trends of higher levels of metals as Al, Cu, Cr and Fe. Photosynthesis was also not affected by site, showing healthy organisms, especially in brown macroalgae, likely due to their great dimensions and morphological complexity. Finally, data did not demonstrate a relationship between metal accumulation and photosynthetic performance, evidencing low anthropogenic-derived impacts associated with metal excess in the area. Green macroalgae, especially Monostroma hariotti, are highlighted as reliable for further metal biomonitoring assessments. In the most ambitious to date seaweed biomonitoring effort conducted towards the Austral pole, this study improved by 91% the overall knowledge on metal accumulation in macroalgae from Antarctica, being the first report in species as Sarcopeltis antarctica and Plocamium cartilagineum. These findings may suggest that human short- and long-range metal influence on Antarctic coastal ecosystems still remains under control.
Afficher plus [+] Moins [-]Is mulch film itself the primary source of meso- and microplastics in the mulching cultivated soil? A preliminary field study with econometric methods
2022
Xu, Li | Xu, Xiangbo | Li, Chang | Li, Jing | Sun, Mingxing | Zhang, Linxiu
There has been an increasing interest in the pollution caused by meso- and microplastics (MMPs) in terrestrial ecosystems. Mulch film was once considered to be the most important source of MMPs in the mulching cultivated soil. However, the academic community has not given sufficient scientific evidence. In this study, stratified random sampling method was used to selectively interview households in Hebei province, China (400 households, 20 villages, 5 counties). Finally, household characteristics and mulch film use behavior of 41 households were collected, and corresponding soil samples were sampled. The results showed that 1) the abundance of MMPs was 29.3 ± 33.1 items·kg⁻¹ (DW) and the particle size of MMPs was 2.95 × 10³±1.75 × 10³ μm, and the proportion of MMPs derived from Polyethylene (PE) was only 18.8%; 2) the mass of MMPs was 2.90 ± 3.72 mg kg⁻¹ (DW) and the proportion of PE MMPs was 43.75%, which has the highest mass percentage; 3) After controlling the endogenous and dummy variables, the use history of mulch film (HistMF) was found to be positively correlated to the abundance of MMPs and inversely correlated to the particle size, but nor with the mass of MMPs; 4) Regarding the heterogeneous characteristics of MMPs, including particle size, color, shape, and type, the findings found the absence of a significant correlation between HistMF and the abundance and mass of PE. In summary, mulch-derived MMPs are not the primary source of MMPs in the mulching cultivated soil in terms of abundance but probably be in terms of mass.
Afficher plus [+] Moins [-]A common fungicide tebuconazole promotes colitis in mice via regulating gut microbiota
2022
Meng, Zhiyuan | Sun, Wei | Liu, Wan | Wang, Yu | Jia, Ming | Tian, Sinuo | Chen, Xiaojun | Zhu, Wentao | Zhou, Zhiqiang
As a common fungicide, tebuconazole are ubiquitous in the natural environment and poses many potential risks. In this study, we examined the effects of exposure to tebuconazole on colitis in mice and explored its underlying mechanism. Specifically, exposure to tebuconazole could cause structural damage and inflammatory cell infiltration in colon tissue, activate the expression of inflammation-related genes, disrupt the expression of barrier function-related genes, and induce the colonic inflammation in mice. Similarly, exposure to tebuconazole could also exacerbate DSS-induced colitis in mice. In addition, we found that tebuconazole also could change the composition of the gut microbiota. In particular, tebuconazole significantly increases the relative abundance of Akkermansia of mice. Moreover, tebuconazole resulted in metabolic profiles disorders of the serum, leading to significant changes in the relative contents of metabolites involving glycolipid metabolism and amino acid metabolism. Particularly, the results of the gut microbiota transplantation experiment showed that exposure to tebuconazole could induced colonic inflammation in mice in a gut microbiota–dependent manner. Taken together, these results indicated that tebuconazole could induce colitis in mice via regulating gut microbiota. Our findings strongly support the concept that the gut microbiota is a key trigger of inflammatory bowel disease caused by pesticide intake.
Afficher plus [+] Moins [-]β-Glucosidases as dominant dose-dependent regulators of Oryza sativa L. in response to typical organic pollutant exposures
2022
Shao, Zexi | Liu, Na | Wang, Wei | Zhu, Lizhong
Understanding the metabolic defense and compensation to maintain homeostasis is crucial for assessing the potential health risk of organic pollutants in crops. Currently, limited understanding is available regarding the targeted metabolic pathways and response mechanism under contaminant stress. This study showed that ciprofloxacin (CIP) at the environmental concentrations (1, 5, 25, 50 mg/L) did not significantly inhibit growth or cause severe oxidative damage to rice (Oryza sativa L.). Instead, the increment in CIP concentration induced a series of sequential metabolic disorders, which were characterized predominantly by primary and secondary metabolic disturbances, including phenylpropanoid biosynthesis, the carbohydrate, lipid and amino acid metabolism. After CIP in vivo exceeded a certain threshold level (>0.29 mg/g dry weight), β-glucosidases (BGLUs) mediated the transition from the activation of the genes related to phenylpropanoid biosynthesis to the inhibition of the genes related to carbohydrate metabolism in rice. In particular, starch and sucrose metabolism showed the most profound perturbation stressed by environmental concentrations of CIP (5 mg/L) and other tested organic pollutants (10 μg/L of tricyclazole, thiamethoxam, polybrominated diphenyl ethers, and polychlorinated biphenyls). Besides, the key genes encoding endoglucanase and BGLU were significantly downregulated (|log₂FC| > 3.0) under 100 μg/L of other tested organic pollutants, supporting the transition from the activation of secondary defense metabolism to the disruption of primary energy metabolism. Thus, in addition to bioaccumulation, changes in BGLU activity and starch and sucrose metabolism can reflect the potential adverse effects of pollutants on rice. This study explained the stepwise metabolic and transcriptional responses of rice to organic pollutants, which provided a new reference for the comprehensive evaluation of their environmental risks.
Afficher plus [+] Moins [-]Smoke and the eyes: A review of the harmful effects of wildfire smoke and air pollution on the ocular surface
2022
Jaiswal, Sukanya | Jalbert, Isabelle | Schmid, Katrina | Tein, Natasha | Wang, Sarah | Golebiowski, Blanka
Wildfires are occurring worldwide with greater frequency and intensity. Wildfires, as well as other sources of air pollution including environmental tobacco smoke, household biomass combustion, agricultural burning, and vehicular emissions, release large amounts of toxic substances into the atmosphere. The ocular surface is constantly exposed to the ambient air and is hence vulnerable to damage from air pollutants. This review describes the detrimental effects of wildfire smoke and air pollution on the ocular surface and resultant signs and symptoms. The latest relevant evidence is synthesised and critically evaluated. A mechanism for the pathophysiology of ocular surface damage will be proposed considering the existing literature on respiratory effects of air pollution. Current strategies to reduce human exposure to air pollutants are discussed and specific possible approaches to protect the ocular surface and manage air pollution induced ocular surface damage are suggested. Further avenues of research are suggested to understand how acute and chronic air pollution exposure affects the ocular surface including the short and long-term implications.
Afficher plus [+] Moins [-]Integrated biotechnology to mitigate green tides
2022
Ren, Cheng-Gang | Liu, Zheng-Yi | Zhong, Zhi-Hai | Wang, Xiao-Li | Qin, Song
Around the world, green tides are happening with increasing frequency because of the dual effects of increasingly intense human activity and climate change; this leads to significant impacts on marine ecology and economies. In the last decade, the world's largest green tide, which is formed by Ulva/Enteromorpha porifera, has become a recurrent phenomenon every year in the southern Yellow Sea (China), and it has been getting worse. To alleviate the impacts of such green tide outbreaks, multiple measures need to be developed. Among these approaches, biotechnology plays important roles in revealing the outbreak mechanism (e.g., molecular identification technology for algal genotypes), controlling and preventing outbreaks at the origin sites (e.g., technology to inhibit propagation), and utilizing valuable algal biomass. This review focuses on the various previously used biotechnological approaches that may be applicable to worldwide seaweed blooms that result from global climate change and environmental degradation.
Afficher plus [+] Moins [-]Contribution of liquid water content enhancing aqueous phase reaction forming ambient particulate nitrosamines
2022
Choi, Na Rae | Park, Seungshik | Ju, Seoryeong | Lim, Yong Bin | Lee, Ji Yi | Kim, Eunhye | Kim, Soontae | Shin, Hye Jung | Kim, Yong Pyo
Contribution of liquid water content (LWC) to the levels of the carcinogenic particulate nitro(so) compounds and the chemistry affecting LWC were investigated based on the observation of seven nitrosamines and two nitramines in rural (Seosan) and urban (Seoul) area in South Korea during October 2019 and a model simulation. The concentrations of both the total nitrosamines and nitramines were higher in Seosan (12.48 ± 16.12 ng/m³ and 0.65 ± 0.71 ng/m³, respectively) than Seoul (7.41 ± 13.59 ng/m³ and 0.24 ± 0.15 ng/m³, respectively). The estimated LWC using a thermodynamic model in Seosan (12.92 ± 9.77 μg/m³) was higher than that in Seoul (6.20 ± 5.35 μg/m³) mainly due to higher relative humidity (75 ± 9% (Seosan); 62 ± 10% (Seoul)) and higher concentrations of free ammonia (0.13 ± 0.09 μmol/m³ (Seosan); 0.08 ± 0.01 μmol/m³ (Seoul)) and total nitric acid (0.09 ± 0.07 μmol/m³ (Seosan); 0.04 ± 0.02 μmol/m³ (Seoul)) in Seosan while neither fog nor rain occurred during the sampling period. The relatively high concentrations of the particulate nitrosamines (>30 ng/m³) only observed probably due to the higher LWC (>10 μg/m³) in Seosan. It implies that aqueous phase reactions involving NO₂ and/or uptake from the gas phase enhanced by LWC could be promoted in Seosan. Strong correlation between the concentrations of nitrosodi-methylamine (NDMA), an example of nitrosamines, simulated by a kinetic box model including the aqueous phase reactions and the measured concentration of NDMA in Seosan (R = 0.77; 0.37 (Seoul)) indicates that the aqueous phase reactions dominantly enhanced the NDMA concentrations in Seosan. On the other hand, it is estimated that the formation of nitrosamines by aqueous phase reaction was not significant due to the relatively lower LWC in Seoul compared to that in Seosan. Furthermore, it is presumed that nitramines are mostly emitted from the primary emission sources. This study implies that the concentration of the particulate nitrosamines can be promoted by aqueous phase reaction enhanced by LWC.
Afficher plus [+] Moins [-]Particle surface area, ultrafine particle number concentration, and cardiovascular hospitalizations
2022
Lin, Shao | Ryan, Ian | Paul, Sanchita | Deng, Xinlei | Zhang, Wangjian | Luo, Gan | Dong, Guang-Hui | Nair, Arshad | Yu, Fangqun
While the health impacts of larger particulate matter, such as PM₁₀ and PM₂.₅, have been studied extensively, research regarding ultrafine particles (UFPs or PM₀.₁) and particle surface area concentration (PSC) is lacking. This case-crossover study assessed the associations between exposure to PSC and UFP number concentration (UFPnc) and hospital admissions for cardiovascular diseases (CVDs) in New York State (NYS), 2013–2018. We used a time-stratified case-crossover design to compare the PSC and UFPnc levels between hospitalization days and control days (similar days without admissions) for each CVD case. We utilized NYS hospital discharge data to identify all CVD cases who resided in NYS. UFP simulation data from GEOS-Chem-APM, a state-of-the-art chemical transport model, was used to define PSC and UFPnc. Using a multi-pollutant model and conditional logistic regression, we assessed excess risk (ER)% per inter-quartile change of PSC and UFPnc after controlling for meteorological factors, co-pollutants, and time-varying variables. We found immediate and lasting associations between PSC and overall CVDs (lag0–lag0-6: ERs% (95% CI%) ranges: 0.4 (0.1,0.7) - 0.9 (0.7–1.2), and delayed and prolonged ERs%: 0.1–0.3 (95% CIs: 0.1–0.5) between UFPnc and CVDs (lag0-3–lag0-6). Exposure to larger PSC was associated with immediate ER increases in stroke, hypertension, and ischemic heart diseases (1.1%, 0.7%, 0.8%, respectively, all p < 0.05). The adverse effects of PSC on CVDs were highest among children (5–17 years old), in the fall and winter, and during cold temperatures. In conclusion, we found an immediate, lasting effects of PSC on overall CVDs and a delayed, prolonged impact of UFPnc. PSC was a more sensitive indicator than UFPnc. The PSC effects were higher among certain CVD subtypes, in children, in certain seasons, and during cold days. Further studies are needed to validate our findings and evaluate the long-term effects.
Afficher plus [+] Moins [-]Elucidating the biodegradation pathway and catabolic genes of benzophenone-3 in Rhodococcus sp. S2-17
2022
Baek, Ju Hye | Kim, Kyung Hyun | Lee, Yun Hee | Jeong, Sang Eun | Jin, Hyun Mi | Jia, Baolei | Jeon, Che Ok
A new bacterium, Rhodococcus sp. S2-17, which could completely degrade an emerging organic pollutant, benzophenone-3 (BP-3), was isolated from contaminated sediment through an enrichment procedure, and its BP-3 catabolic pathway and genes were identified through metabolic intermediate and transcriptomic analyses and biochemical and genetic studies. Metabolic intermediate analysis suggested that strain S2-17 may degrade BP-3 using a catabolic pathway progressing via the intermediates BP-1, 2,4,5-trihydroxy-benzophenone, 3-hydroxy-4-benzoyl-2,4-hexadienedioic acid, 4-benzoyl-3-oxoadipic acid, 3-oxoadipic acid, and benzoic acid. A putative BP-3 catabolic gene cluster including cytochrome P450, flavin-dependent oxidoreductase, hydroxyquinol 1,2-dioxygenase, maleylacetate reductase, and α/β hydrolase genes was identified through genomic and transcriptomic analyses. Genes encoding the cytochrome P450 complex that demethylates BP-3 to BP-1 were functionally verified through protein expression, and the functions of the other genes were also verified through knockout mutant construction and intermediate analysis. This study suggested that strain S2-17 might have acquired the ability to catabolize BP-3 by recruiting the cytochrome P450 complex and α/β hydrolase, which hydrolyzes 4-benzoyl-3-oxoadipic acid to benzoic acid and 3-oxoadipic acid, genes, providing insights into the recruitment of genes of for the catabolism of emerging organic pollutants.
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