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Internal distribution and fate of persistent organic contaminants (PCDD/Fs, DL-PCBs, HBCDs, TBBPA, and PFASs) in a Bos Taurus
2020
Shin, Eun-su | Jeong, Yuna | Barghi, Mandana | Seo, Sung-Hee | Kwon, Sae Yun | Chang, Yoon Seok
While terrestrial organisms such as livestock are consumed regularly, studies of internal distribution and bioaccumulation of persistent organic pollutants (POPs) have been focused more on aquatic organisms. In this study, we have assessed the internal distribution and fate of legacy (PCDD/Fs and PCBs) and emerging POPs (HBCDs and PFASs), and TBBPA in 42 tissues of a Bos Taurus. PCDD/Fs, DL-PCBs, and HBCDs were found 3, 4, and 4-fold higher in the lipid-rich organs (subcutaneous fat, visceral fat, large intestine) compared to the remaining organs and muscles, owing to their hydrophobic properties. The TBBPA concentration in the excrement was 36-fold higher compared to the average tissues, suggesting a short internal half-life of TBBPA. Among PFASs, PFUnDA displayed 98% contribution from all ionic PFASs in the tissues due to its strong binding affinity, high exposure via feed and water, and increasing emergence of PFUnDA and its precursors in the Southeast Asian countries. While our study suggests that, at the moment, there is no significant health risks to the general Korean population, the future changes in environmental exposure as well as the internal dynamics and fate of various POPs species should be kept in mind when consuming various parts of livestock.
Показать больше [+] Меньше [-]Sodium fluoride exposure triggered the formation of neutrophil extracellular traps
2020
Wang, Jing-Jing | Wei, Zheng-Kai | Han, Zhen | Liu, Zi-Yi | Zhang, Yong | Zhu, Xing-Yi | Li, Xiao-Wen | Wang, Kai | Yang, Zheng-Tao
In recent years, numerous studies paid more attention to the molecular mechanisms associated with fluoride toxicity. However, the detailed mechanisms of fluoride immunotoxicity in bovine neutrophils remain unclear. Neutrophil extracellular traps (NETs) is a novel immune mechanism of neutrophils. We hypothesized that sodium fluoride (NaF) can trigger NETs activation and release, and investigate the related molecular mechanisms during the process. We exposed peripheral blood neutrophils to 1 mM NaF for 120 min in bovine neutrophils. The results showed that NaF exposure triggered NET-like structures decorated with histones and granule proteins. Quantitative measurement of NETs content correlated positively with the concentration of NaF. Mechanistically, NaF exposure increased reactive oxygen species (ROS) levels and phosphorylation levels of ERK, p38, whereas inhibiting the activities of superoxide dismutase (SOD) and catalase (CAT) compared with control neutrophils. NETs formation is induced by NaF and this effect was inhibited by the inhibitors diphenyleneiodonium chloride (DPI), U0126 and SB202190. Our findings described the potential importance of NaF-triggered NETs related molecules, which might help to extend the current understanding of NaF immunotoxicity.
Показать больше [+] Меньше [-]Impacts of different sources of animal manures on dissemination of human pathogenic bacteria in agricultural soils
2020
Li, Jinyang | Chen, Qinglin | Li, Helian | Li, Shiwei | Liu, Yinghao | Yang, Liyuan | Han, Xuemei
The human pathogenic bacteria (HPB) in animal feces may disseminate to agricultural soils with their land application as organic fertilizer. However, the knowledge about the impacts of different sources and rates of animal manures on the temporal changes of soil HPB remains limited, which hamper our ability to estimate the potential risks of their land application. Here, we constructed an HPB database including 565 bacterial strains. By blasting the 16 S rRNA gene sequences against the database we explored the occurrence and fate of HPB in soil microcosms treated with two rates of swine, poultry or cattle manures. A total of 30 HPB were detected in all of manure and soil samples. Poultry manure at the high level obviously improved the abundance of soil HPB. The application of swine manure could introduce concomitant HPB into the soils. Of which, Pseudomonas syringae pv. syringae B728a and Escherichia coli APEC O78 may deserve more attention because of their survival for a few days in manured soils and being possible hosts of diverse antibiotic resistance genes (ARGs) as revealed by co-occurrence pattern. Bayesian source tracking analysis showed that the HPB derived from swine manure had a higher contribution to soil pathogenic communities than those from poultry or cattle manures in early days of incubation. Mantel test together with variation partitioning analysis suggested that bacterial community and soil physicochemical properties were the dominant factors determining the profile of HPB and contributed 64.7% of the total variations. Overall, our results provided experimental evidence that application of animal manures could facilitate the potential dissemination of HPB in soil environment, which should arouse sufficient attention in agriculture practice and management to avoid the threat to human health.
Показать больше [+] Меньше [-]Urbanization and cattle density are determinants in the exposure to anticoagulant rodenticides of non-target wildlife
2019
López-Perea, Jhon J. | Camarero, Pablo R. | Sánchez-Barbudo, Ines S. | Mateo, Rafael
The persistence and toxicity of second generation anticoagulant rodenticides (SGARs) in animal tissues make these compounds dangerous by biomagnification in predatory species. Here we studied the levels of SGARs in non-target species of wildlife and the environmental factors that influence such exposure. Liver samples of terrestrial vertebrates (n = 244) found dead between 2007 and 2016 in the region of Aragón (NE Spain) were analysed. The presence of SGARs was statistically analysed with binary or ordinal logistic models to study the effect of habitat characteristics including human population density, percentage of urban surface, livestock densities and surface of different types of crops. SGARs residues were detected in 83 (34%) of the animals and levels >200 ng/g were found in common raven (67%), red fox (50%), red kite (38%), Eurasian eagle-owl (25%), stone marten (23%), Eurasian buzzard (17%), northern marsh harrier (17%), and Eurasian badger (14%). The spatial analysis revealed that the presence of SGARs residues in wildlife was more associated with the use of these products as biocides in urban areas and cattle farms rather than as plant protection products in agricultural fields. This information permits to identify potential habitats where SGARs may pose a risk for predatory birds and mammals.
Показать больше [+] Меньше [-]Comparing emissions from a cattle pen as measured by two micrometeorological techniques
2017
Bai, Mei | Sun, Jianlei | Denmead, Owen T. | Chen, Deli
Accurate measurement of ammonia (NH3) emissions from livestock pens is challenging. Two micrometeorological techniques, the integrated horizontal flux (IHF) and the backward Lagrangian stochastic (bLS) dispersion technique were used to measure NH3 emissions from an isolated cattle pen (20 × 20 m) in Victoria, Australia. The bLS technique is simple and insensitive to the presence of animals, but typically gives discontinuous measurements due to the need for target wind directions and wind conditions above accepted thresholds. In contrast, the IHF technique as implemented here gives near-continuous measurements with no restriction on wind directions. However, IHF needs more complex field measurements, and there are ambiguities when applied to an animal pen due to the presence of animals. Over the 29 days of our experiment, we collected 124 coincidental bLS and IHF emission measurements from the pen (30−min each). We found no statistical difference in the bLS and IHF calculations when the IHF turbulent flux correction factor (TFcor) was set to 15%. Our results confirm that the IHF and bLS techniques, using independent sensors and having very different equipment layouts, gives nearly equivalent results. This suggests the choice of the two methods in future experiments can focus on their different strengths and weaknesses.
Показать больше [+] Меньше [-]Metal exposure in cows grazing pasture contaminated by iron industry: Insights from magnetic particles used as tracers
2016
Ayrault, Sophie | Catinon, Mickaël | Boudouma, Omar | Bordier, Louise | Agnello, Gregory | Reynaud, Stéphane | Tissut, Michel
Magnetic particles (MP) emitted by an iron smelter were used to investigate the exposure of cows grazing on a grassland polluted by these MP and by large amounts of potentially toxic elements (PTE). The morphology as well as the chemical composition of the MP separated from cow dung were studied. Large amounts of typical MP were found (1.1 g kg−1 dry weight) in the cow dung sampled from the exposed site, whereas these particles were absent from the reference unpolluted site. The ingested MP were mainly technogenic magnetic particles (TMP) emitted by the smelter. Considering the MP concentration in the grazed grass on the exposed site, it was concluded that cows absorb the MP not only from the grass but also from the soil surface. The results of a mild acidic leaching of the MP suggested that the particles were possibly submitted to a superficial dissolution in the abomasum, pointing at a potential route of transfer of the PTE originating from the TMP and leading into food chains. TMP were only a small part of the anthropogenic contamination having affected the soil and the dung. However, due to their unequivocal signature, TMP are a powerful tracer of the distribution of PTE in the different compartments constituting the food chains and the ecosystems. Furthermore, the measurement of the particle sizes gave evidence that a noticeable proportion of the MP could enter the respiratory tract.
Показать больше [+] Меньше [-]Predicting fecal indicator organism contamination in Oregon coastal streams
2015
Pettus, Paul | Foster, Eugene | Pan, Yangdong
In this study, we used publicly available GIS layers and statistical tree-based modeling (CART and Random Forest) to predict pathogen indicator counts at a regional scale using 88 spatially explicit landscape predictors and 6657 samples from non-estuarine streams in the Oregon Coast Range. A total of 532 frequently sampled sites were parsed down to 93 pathogen sampling sites to control for spatial and temporal biases. This model's 56.5% explanation of variance, was comparable to other regional models, while still including a large number of variables. Analysis showed the most important predictors on bacteria counts to be: forest and natural riparian zones, cattle related activities, and urban land uses. This research confirmed linkages to anthropogenic activities, with the research prediction mapping showing increased bacteria counts in agricultural and urban land use areas and lower counts with more natural riparian conditions.
Показать больше [+] Меньше [-]Year-round grazing to counteract effects of atmospheric nitrogen deposition may aggravate these effects
2014
van Dobben, H.F. | Wamelink, G.W.W. | Klimkowska, A. | Slim, P.A. | van Til, M.
Excessive nitrogen input in natural ecosystems is a major threat to biodiversity. A coastal dune area near Amsterdam in the Netherlands suffers from high atmospheric nitrogen deposition affecting sensitive habitats such as fixed coastal dunes with herbaceous vegetation (‘grey dunes’). To mitigate its effect year round grazing was applied from 2007 until 2012. In winter, when natural food supply is low, the cattle received supplementary hay that caused additional inputs of nitrogen. Estimates based on nitrogen contents of hay, as well as of manure, showed the input through winter feeding (c. 3–14 kg N ha−1.y−1) is in the same order of magnitude as both the actual deposition (c. 17 kg N ha−1.y−1) and the critical load for a number of herbaceous habitat types (10–15 kg N ha−1.y−1). Locally, the effect of winter feeding adds to the effect of nitrogen redistribution within the area caused by the cattle's terrain usage. We conclude that winter feeding may aggravate effects of atmospheric nitrogen deposition.
Показать больше [+] Меньше [-]Blood Pb and δ-ALAD inhibition in cattle and sheep from a Pb-polluted mining area
2012
Rodríguez-Estival, Jaime | Barasona, José A. | Mateo, Rafael
The effects of Pb pollution on cattle and sheep raised in an ancient mining area were studied through the use of blood Pb (PbB) levels and δ-aminolevulinic acid dehydratase (δ-ALAD) activity. Lead levels in livestock blood from the mining area (n=110) were significantly elevated when compared to the controls (n=79). In 91.4% of cattle (n=58) and 13.5% of sheep (n=52) sampled in the mining area, PbB levels corresponded to subclinical exposure (6–35μg/dl). Two young cattle (<2 years) from the mining area (n=5) had PbB levels indicative of clinical poisoning (>35μg/dl). Elevated PbB was also accompanied by δ-ALAD activity inhibition in blood, which confirms that measurable effects of Pb poisoning were taking place. Observed PbB levels suggest that a potential risk to human consumers of beef from the Pb polluted areas may also exist, as has been shown previously for game meat from the same mining area.
Показать больше [+] Меньше [-]Mobility of radium and trace metals in sediments of the Winterbeek: Application of sequential extraction and DGT techniques
2010
Gao, Y. | Baeyens, W. | Galan, S De | Poffijn, A. | Leermakers, M.
For several decades, phosphate ores containing 226Ra as well as several trace metals have been processed in Belgium to produce calcium phosphate for use in cattle food. The waste water is discharged in two small rivers, the Laak and the Winterbeek. In this study, the levels of 226Ra and trace metals in surface water and sediments of the Winterbeek were investigated and the mobility of these compounds was assessed using DGT (Diffusive Gradient in Thin Films) and sequential extraction techniques. The concentrations of 226Ra and trace metals in water and sediment indicate a decreasing trend in inputs to the Winterbeek. The mobility of 226Ra, assessed by DGT, is related to the reductive mobilization of Fe. The sequential extraction technique shows that at some stations an important fraction of 226Ra is found to labile sediment phases. Diffusive 226Ra sediment fluxes, are however, relatively small and have only a minor contribution to the water column concentration of 226Ra.
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