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Atmospheric NH3 dynamics at a typical pig farm in China and their implications
2014
Xu, Wen | Zheng, Kun | Liu, Xuejun | Meng, Lingmin | Huaitalla, Roxana M. | Shen, Jianlin | Hartung, Eberhand | Gallmann, Eva | Roelcke, Marco | Zhang, Fusuo
This study investigated NH3 concentrations in and around a large–scale commercial pig farm with the so–called “gan qing fen” manure collection system near Beijing from April 2009 to August 2011. NH3 emissions from the fattening pig houses were calculated based on the heat balance method. Monthly concentrations of time–averaged NH3 in and near the pig house averaged 3 392 and 182μg m−3 and ranged from 1 044 to 7 514μg m−3 and 35.4 to 478μg m−3, respectively. Daily NH3 concentrations varied from 767 to 2 389μg m−3 in the pig house and 184 to 574μg m−3 outside. Time–averaged NH3 concentrations varied from 21.6 to 558μg m−3 within the farm while concentrations outside the farm ranged from 38.4μg m−3 at a distance of 10m to 14.0μg m−3 at a distance of 650m. Calculated average NH3 emission rates per pig were highest in summer and lowest in winter, 8.0±5.5 (average±standard deviation) and 2.0±0.4g day−1 pig−1, respectively. Average NH3 emission rates (normalized to 500kg live weight, expressed as AU) were highest during spring and summer (average 65.4±25.0 and 53.7±35.6 g day−1 AU−1) and lowest in autumn and winter (average 25.4±9.3 and 13.7±2.7g day−1 AU−1). Average NH3 emission per area (m2) from house was almost three times higher in summer (average 3.5±2.4g day−1 m−2) than in winter (average 1.1±0.3g day−1 m−2).
Mostrar más [+] Menos [-]Total and organic mercury concentrations in the muscles of Pacific albacore (Thunnus alalunga) and bigeye tuna (Thunnus obesus)
2014
Chen, Chiee-Young | Lai, Chien-Cheng | Chen, Kuo-Shu | Xu, Jianzhong | Hung, Chin-Chang | Chen, Meng-Hsien
Muscles of 115 North Pacific albacore (ALB, Thunnus alalunga) and 75 Pacific bigeye tuna (BET, Thunnus obesus), collected from 2001 to 2006, were analyzed. No ALB, but 13 large BET had organic mercury (OHg) concentrations exceeding 1μgg−1 wet weight. For both ALB and BET, total mercury (THg) and OHg concentrations were significantly and positively correlated with fork length (FL) and body weight. The muscle Hg bioaccumulation rates of BET were higher than those of ALB, particularly in the adult fish. Moreover, the lines had crossover points among the two species that imply the young BET (FL<110cm) contains lower muscle Hg concentrations than ALB of the same size. The suggested weekly dietary intake of ALB and small-BET meats is 340g, and of BET meat it is 150g for a 60-kg person based on the provisional tolerable weekly intake (PTWI) of methylmercury set by the WHO.
Mostrar más [+] Menos [-]Multi-biomarker responses in green mussels exposed to PFCs: effects at molecular, cellular, and physiological levels
2014
Liu, Changhui | Gin, Karina Y. H. | Chang, Victor W. C.
Perfluorinated chemicals (PFCs) are extremely persistent and have been found extensively in the environment and wildlife. Oceans are the final sink for many persistent organic pollutants (POPs) including PFCs. However, to date, there has been a lack of studies that investigated the environmental consequences of PFCs on marine organisms. To fill in this gap, environmental toxicity of two dominant PFCs, perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA), was examined in a sentinel species, green mussel Perna viridis, using a series of biomarkers corresponding to different biological levels (molecular, cellular, and physiological). Correlations among these biomarkers were also investigated. The results showed that the tested compounds can induce a series adverse effect at different biological levels, including oxidative stress, DNA damage, membrane instability, suppressed filtration rate, and reduced body weight. Correlation analysis revealed that excess production of reactive oxygen species could be the major toxic pathway. An indirect mode of toxic action was also explored where adverse impacts could be secondary effects of PFC exposure. The joint analysis of biomarkers from multiple biological levels resulted in a comprehensive understanding of how PFC exposure can influence the health of organisms. The correlations of these biomarkers also provided a new perspective of the ecological consequences of PFCs.
Mostrar más [+] Menos [-]Vitamin E prevents glucose metabolism alterations induced by static magnetic field in rats
2014
Ghodbane, Soumaya | Amara, Salem | Lahbib, Aida | Louchami, Karim | Sener, Abdullah | Sakly, Mohsen | Abdelmelek, Hafedh
In the present study, we investigate the effects of a possible protective role of vitamin E (vit E) or selenium (Se) on glucose metabolism disruption induced by static magnetic field (SMF) in rats. Rats have been exposed to SMF (128 mT, 1 h/day during 5 days). Our results showed that SMF failed to alter body weight and relative liver weight. Our data demonstrated that exposure to SMF increased (+21 %) blood glucose level and caused a decrease (−15 %) in liver glycogen content. Moreover, the same treatment induced a reduction of pancreatic islet area. Interestingly, supplementation with vit E (DL α-tocopherol acetate, 150 mg/kg per os during 5 days) prevented alterations induced by SMF on glucose metabolism and liver glycogen content, whereas supplementation with Se (Na₂SeO₃, 0.20 mg/l, in drinking water for 4 weeks) restored only hepatic glycogen contents. By contrast, both vit E and Se failed to correct the area of pancreatic islets.
Mostrar más [+] Menos [-]Antimutagenic and antigenotoxic potential of grape juice concentrate in blood and liver of rats exposed to cadmium
2014
de Moura, Carolina Foot Gomes | Ribeiro, Flávia Andressa Pidone | Pacheco de Jesus, Gustavo Protasio | Pereira da Silva, Victor Hugo | Oshima, Celina Tizuko Fujiyama | Gollücke, Andréa Pittelli Boiago | Aguiar, Odair, Jr | Ribeiro, Daniel Araki
The aim of this study was to evaluate the antimutagenic and antigenotoxic potential of grape juice concentrate in rodent organs exposed to cadmium chloride intoxication. A total of 15 Wistar rats were distributed into three groups (n = 5), as follows: control group (CTRL; nontreated group), cadmium group (Cd), and cadmium-grape juice group (Cd + GJ). Exposed animals received intraperitoneal injection of cadmium chloride (1.2 mg/kg body weight) diluted in water and, after 15 days, Cd + GJ group received grape juice concentrate for 15 days, by gavage (0.8 mL, 1.18 mg of polyphenols kg⁻¹ day⁻¹). Grape juice concentrate was able to decrease genotoxic effects induced by cadmium in peripheral blood and liver cells as depicted by single cell gel (comet) and micronucleus assays. A decrease for anti-8-hydroxy-20-deoxyguanosine (8OHdG) expression in hepatocytes of animals exposed to cadmium and treated with grape juice concentrate was also detected. Higher CuZn-SOD activity was observed in liver cells of the Cd + GJ group. No remarkable differences were seen regarding Mn-SOD activity among groups. Taken together, our results demonstrate that grape juice concentrate was able to exert antimutagenic and antigenotoxic activities in blood and liver cells of rats exposed to cadmium.
Mostrar más [+] Menos [-]Triazole-induced toxicity in developing rare minnow (Gobiocypris rarus) embryos
2014
Zhu, Bin | Liu, Lei | Gong, Yu-Xin | Ling, Fei | Wang, Gao-Xue
Using rare minnow (Gobiocypris rarus) at early-life stages as experimental models, the developmental toxicity of five widely used triazole fungicides (myclobutanil, fluconazole, flusilazole, triflumizole, and epoxiconazole) were investigated following exposure to 1–15 mg/L for 72 h. Meanwhile, morphological parameters (body length, body weight, and heart rate), enzyme activities (superoxide dismutase (SOD), glutathione S-transferase (GST), adenosine triphosphatase (ATPase), and acetyl cholinesterase (AChE)), and mRNA levels (hsp70, mstn, mt, apaf1, vezf1, and cyp1a) were also recorded following exposure to 0.2, 1.0, and 5.0 mg/L for 72 h. Results indicated that increased malformation and mortality, decreased body length, body weight, and heart rate provide a concentration-dependent pattern; values of 72 h LC₅₀(median lethal concentration) and EC₅₀(median effective concentration) ranged from 3 to 12 mg/L. Most importantly, the results of the present study suggest that even at the lowest concentration, 0.2 mg/L, five triazole fungicides also caused notable changes in enzyme activities and mRNA levels. Overall, the present study points out that those five triazole fungicides are highly toxic to the early development of G. rarus embryos. The information presented in this study will be helpful in better understanding the toxicity induced by triazole fungicides in fish embryos.
Mostrar más [+] Menos [-]Polychlorinated biphenyl (118) activates osteoclasts and induces bone resorption in goldfish
2014
Yachiguchi, Koji | Matsumoto, Noriko | Haga, Yuki | Suzuki, Motoharu | Matsumura, Chisato | Tsurukawa, Masahiro | Okuno, Toshihiro | Nakano, Takeshi | Kawabe, Kimi | Kitamura, Kei-ichiro | Toriba, Akira | Hayakawa, Kazuichi | Chowdhury, Vishwajit S. | Endo, Masato | Chiba, Atsuhiko | Sekiguchi, Toshio | Nakano, Masaki | Tabuchi, Yoshiaki | Kondo, Takashi | Wada, Shigehito | Mishima, Hiroyuki | Hattori, Atsuhiko | Suzuki, Nobuo
To analyze the effect of polychlorinated biphenyl (PCB) 118 on fish bone metabolism, we examined osteoclastic and osteoblastic activities, as well as plasma calcium levels, in the scales of PCB (118)-injected goldfish. In addition, effect of PCB (118) on osteoclasts and osteoblasts was investigated in vitro. Immature goldfish, in which the endogenous effects of sex steroids are negligible, were used. PCB (118) was solubilized in dimethyl sulfoxide at a concentration of 10 ppm. At 1 and 2 days after PCB (118) injection (100 ng/g body weight), both osteoclastic and osteoblastic activities, and plasma calcium levels were measured. In an in vitro study, then, both osteoclastic and osteoblastic activities as well as each marker mRNA expression were examined. At 2 days, scale osteoclastic activity in PCB (118)-injected goldfish increased significantly, while osteoblastic activity did not change significantly. Corresponding to osteoclastic activity, plasma calcium levels increased significantly at 2 days after PCB (118) administration. Osteoclastic activation also occurred in the marker enzyme activities and mRNA expressions in vitro. Thus, we conclude that PCB (118) disrupts bone metabolism in goldfish both in vivo and in vitro experiments.
Mostrar más [+] Menos [-]Mercury (Hg) in fish consumed by the local population of the Jaguaribe River lower basin, Northeast Brazil
2014
Costa, B. G. B. | Lacerda, L. D.
The knowledge of Hg concentrations in fish is of considerable interest since these organisms are a major source of protein to coastal human populations and fishing communities. The main source of human exposure to Hg contamination occurs through the consumption of fish. In this paper, we compare Hg concentration in 13 fish species from Jaguaribe River lower basin and an adjacent coastal region in the northeastern coast of Brazil. We sampled fish from three stretches of the river: fluvial, estuarine, and marine regions. We tested the hypothesis that Hg concentration in muscle tissue vary according to species, location, and trophic level. Significant differences were observed among species and trophic level, but these could not be observed among the regions studied. As expected, the highest concentrations were observed in carnivorous fish (5.6–107.5; 26.9 ± 18.8 ng g⁻¹). Hg concentrations observed in this study are similar to those observed in regions of low environmental contamination. We estimated Hg intake to vary between 0.02 and 0.22 ng Hg kg body weight⁻¹ week⁻¹, for the average body weight of 56.7 kg, which was considered as low exposure and therefore, a low risk to consumers of fish from the regions studied.
Mostrar más [+] Menos [-]Distribution of feminizing compounds in the aquatic environment and bioaccumulation in wild tilapia tissues
2014
Chen, Wenling | Gwo, Jin-Chywan | Wang, Gen-Shuh | Chen, Chia-Yang
This study sampled six times of river water, sediment, and tilapia (Oreochromis niloticus) in the Dan-Shui River, Taipei, Taiwan; 10 feminizing compounds were analyzed using ultra-performance liquid chromatography-tandem mass spectrometry. Bisphenol A (508 ± 634 ng/L, geometric mean (GM) 303 ng/L) and nonylphenol (491 ± 570 ng/L, GM 328 ng/L) were the most abundant among analytes in the river water. Nonylphenol (770 ± 602 ng/g wet weight, GM 617 ng/g wet weight) was also the highest in sediment. Fish may uptake nonylphenol and nonylphenol ethoxylates from river water and sediment because there were significant correlations between the concentrations in these matrixes and those in fish tissues (r ₛ ranged from 0.21 to 0.49, p < 0.05). The bioaccumulation of nonylphenol, nonylphenol ethoxylates and bisphenol A in gonad, eggs, and liver was much higher than that in muscle (e.g. mean bioaccumulation factors of nonylphenol were 27,287, 20,971, 9,576 and 967, respectively) and might result in low liver fractions in fish body weights (0.66 % ± 0.39 %, GM 0.55 %) and the skewed sex ratio of fish (male to female = 0.52). This innovative study linked the environmental and internal doses statistically in the globally distributed wild fish by analyzing feminizing compounds in water, sediment, and four fish tissues including gonad and eggs.
Mostrar más [+] Menos [-]Effects of in utero di-butyl phthalate and butyl benzyl phthalate exposure on offspring development and male reproduction of rat
2014
Ahmad, Rahish | Gautam, A. K. (Anil Kumar) | Verma, Y. | Sedha, S. | Kumar, Sunil
The study was conducted to assess the effects of in utero di-butyl phthalate (DBP) and butyl benzyl phthalate (BBP) exposure during late gestation on offspring’s development and reproductive system of male rats. Pregnant rats were treated orally with DBP (2, 10, 50 mg/kg), BBP (4, 20, 100 mg/kg), and diethylstilbestrol (DES) 6 μg/kg (positive control) from GD14 to parturition. A significant reduction in dams’ body weight on GD21 in DBP-, BBP-, and DES-treated groups was observed. The gestation length was considerably elevated in the treated groups. Decline in male pups’ body weight was significant at PND75 in DBP- (50 mg/kg), BBP- (20,100 mg/kg), and DES-treated groups. The weight of most of the reproductive organs and sperm quality parameters was impaired significantly in DBP- (50 mg/kg) and BBP- (100 mg/kg) treated groups. Further, a non-significant decline in testicular spermatid count and daily sperm production was also monitored in treated groups. A significant reduction in serum testosterone level in BBP (100 mg/kg), whereas the testicular activity of 17β-HSD was declined non-significantly in the treated groups with respect to control. The data suggests that DBP and BBP exposure during late gestation period might have adverse effects on offspring’s development, spermatogenesis, and steroidogenesis in adult rats.
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