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Diazinon exposure produces histological damage, oxidative stress, immune disorders and gut microbiota dysbiosis in crucian carp (Carassius auratus gibelio) Full text
2021
Tang, Jiali | Wang, Wenqian | Jiang, Yuanhe | Chu, Weihua
Diazinon is a common organophosphate pesticide widely used to control parasitic infections in agriculture. Excessive use of diazinon can have adverse effects on the environment and aquatic animal health. In the present study, the toxic effects of diazinon on the histology, antioxidant, innate immune and intestinal microbiota community composition of crucian carp (Carassius auratus gibelio) were investigated. The results showed that diazinon at the tested concentration (300 μg/L) induced gill and liver histopathological damages. Hepatic total superoxide dismutase (T-SOD), catalase (CAT), and glutathione S-transferase (GST) activities significantly decreased (P < 0.05) by 32.47%, 65.33% and 37.34%, respectively. However, the liver tissue malondialdehyde (MDA) content significantly (P < 0.05) increased by 138.83%. The 300 μg/L diazinon significantly (P < 0.05) downregulated the gene expression of TLR4, MyD88, NF-kB p100 and IL-8 but had no significant effect TNF-α (P = 0.8239). In addition, the results demonstrated that diazinon exposure could affect the intestinal microbiota composition and diversity. Taken together, the results of this study indicated that diazinon exposure can cause damage to crucian carp, induce histopathological damage in gill and liver tissues, oxidative stress in the liver, and innate immune disorders and alter intestinal microbiota composition and diversity.
Show more [+] Less [-]Understanding PFAAs exposure in a generalist seabird species breeding in the vicinity of a fluorochemical plant: Influence of maternal transfer and diet Full text
2021
Lopez-Antia, Ana | Kavelaars, Marwa M. | Müller, Wendt | Bervoets, Lieven | Eens, Marcel
Perfluoroalkyl acids (PFAAs) are a focus of scientific and regulatory attention nowadays. However, PFAAs dynamics in the environment and the factors that determine wildlife exposure are still not well understood. In this study we examined PFAAs exposure in chicks of a generalist seabird species, the lesser black-backed gull (Larus fuscus), breeding 49 km away of a PFAAs hotspot (a fluorochemical plant in Antwerp, Belgium). In order to study the pathways of PFAAs exposure, we measured how chicks’ PFAAs burden varied with age, sex, and body condition. In addition, we related PFAA concentrations to chicks’ diet using stable isotope signatures. For this purpose, we studied plasma PFAA concentrations in 1-week and 4-week-old gull chicks. Only 4 (PFOS, PFOA, PFDA and PFNA) out of the 13 target PFAA compounds were detected. Measured concentrations of PFOS and PFOA were generally high compared to other seabird species but were highly variable between individuals. Furthermore, our results suggest that maternal transfer plays a significant role in determining chicks’ PFAAs burden, and that there are variable sources of exposure for PFOS and PFOA during post-hatching development. The association between PFOS and specific stable isotopes (i.e. δ¹⁵N and δ¹³C) suggests a higher exposure to PFOS in birds with a predominantly marine diet. We also found that males’ condition was positively associated with PFOS plasmatic concentration, probably due to the indirect effect of being fed a high quality (marine) diet which appears PFOS rich. Yet, exact exposure source(s) for PFOA remain(s) unclear. Given that PFOS concentrations measured in some chicks surpassed the toxicity reference value calculated for top avian predators, continued monitoring of exposure and health of this gull population, and other wildlife populations inhabiting the area, is highly recommended.
Show more [+] Less [-]Nutrient accumulation from excessive nutrient surplus caused by shifting from rice monoculture to rice–crayfish rotation Full text
2021
Hou, Jun | Zhang, Dingyue | Zhu, Jianqiang
The potential environmental risk associated with nutrient surplus after switching from rice monoculture (RM) to rice–crayfish rotation (RCR) was assessed in the Jianghan Plains in China. Nutrient surplus was achieved by surveying 32 RM and 69 RCR and determining their nutrient inputs and outputs, and the soil nutrient status for different soil properties were recorded for 0–23 years. The annual average input of N, P₂O₅, and K₂O in RCR was 536, 185, and 253 kg ha⁻¹, respectively, wherein fertilizer and feed accounted for the major fraction of the total nutrient input. For instance, they accounted 58% and 18% of N, 74% and 24% of P₂O₅, and 70% and 30% of K₂O, respectively. The annual apparent surplus of N, P₂O₅, and K₂O was 397, 145, and 225 kg ha⁻¹, respectively, leading to low apparent nutrient use efficiency. Consequently, compared with RM, the total N and soil readily oxidized organic carbon in the upper soil surface (0–20 cm) for the RCR field significantly increased by 0.42–0.96 g kg⁻¹ and 1.63–3.19 g kg⁻¹, respectively. The available N, Olsen P, and exchangeable K of the RCR in the upper soil layer also increased significantly. In the RCR system, a significant positive linear relationship between the apparent accumulated nutrient surplus of N, P, and K elements and the total N, Olsen P, and exchangeable K present in the 0–60 cm soil profile was observed. In RCR, the soil pH in 0–60 cm soil profile and cation exchange capacity in the 0–20 cm soil layer increased as the cultivation time progressed. Nutrient accumulation in the soil not only enhanced soil fertility but also negatively influenced the environment. Therefore, several measures (e.g., new fertilization technologies, new fertilizer, legislation approaches for nutrient surplus, and technical training) should be adopted to control the nutrient surplus.
Show more [+] Less [-]Zearalenone and deoxynivalenol reduced Th1-mediated cellular immune response after Listeria monocytogenes infection by inhibiting CD4+ T cell activation and differentiation Full text
2021
Cai, Guodong | Xia, Sugan | Zhong, Fang | Liu, Shuangshuang | Gu, Jianhong | Yuan, Yan | Zhu, Guoqiang | Zou, Hui | Liu, Zongping | Bian, Jianchun
Based on the fact that mycotoxins and the food-borne bacteria coexist in the natural environment and pose a significant health hazard to humans and animals, it is important to investigate the immunosuppressive mechanism of ZEA (zearalenone), DON (deoxynivalenol), and their combination in bacterial infections. In this study, we established a mouse model of mycotoxin low-dose exposure combined with Listeria monocytogenes infection and investigated the effects of ZEA, DON and their combination on Th1-mediated anti-intracellular bacterial infection based on CD4⁺ T cell activation and differentiation using both in vitro and in vivo analyses. The present study showed that both ZEA and DON aggravated Listeria monocytogenes infection in mice and affected the activation of CD4⁺ T cells and Th1 differentiation, including the effects on costimulatory molecules CD28 and CD152 and on cross-linking of IL-12 and IL-12R, by inhibiting T cell receptor (TCR) signaling. When compared with ZEA, DON was found to have a greater impact on many related indicators. Surprisingly, the combined effects of ZEA and DON did not appear to enhance toxicity compared to treatment with the individual mycotoxins. Our findings more clearly revealed that exposure to low-dose ZEA and DON caused immunosuppression in the body by mechanisms including inhibition of CD4⁺ T cells activation and reduction of Th1 cell differentiation, thus exacerbating infection of animals by Listeria monocytogenes.
Show more [+] Less [-]Integrated transcriptomics and proteomics revealed the distinct toxicological effects of multi-metal contamination on oysters Full text
2021
Li, Yunlong | Wang, Wen-Xiong
The Pearl River Estuary (PRE) is the largest estuary in southern China and under high metal stress. In the present study, we employed an integrated method of transcriptomics and proteomics to investigate the ecotoxicological effects of trace metals on the Hong Kong oyster Crassostrea hongkongensis. Three oyster populations with distinct spatial distributions of metals were sampled, including the Control (Station QA, the lowest metal levels), the High Cd (Station JZ, the highest Cd), and the High Zn–Cu–Cr–Ni (Station LFS, with the highest levels of zinc, copper, chromium, and nickel). Dominant metals in oysters were differentiated by principal component analysis (PCA), and theirgene and protein profiles were studied using RNA-seq and iTRAQ techniques. Of the 2250 proteins identified at both protein and RNA levels, 70 proteins exhibited differential expressions in response to metal stress in oysters from the two contaminated stations. There were 8 proteins altered at both stations, with the potential effects on mitochondria and endoplasmic reticulum by Ag. The genotoxicity, including impaired DNA replication and transcription, was specifically observed in the High Cd oysters with the dominating influence of Cd. The structural components (cytoskeleton and chromosome-associated proteins) were impaired by the over-accumulated Cu, Zn, Cr, and Ni at Station LFS. However, enhanced tRNA biogenesis and exosome activity might help the oysters to alleviate the toxicities resulting from their exposure to these metals. Our study provided comprehensive information on the molecular changes in oysters at both protein and RNA levels in responding to multi-levels of trace metal stress.
Show more [+] Less [-]Where are we? Towards an understanding of the selective accumulation of microplastics in mussels Full text
2021
Li, Jiana | Wang, Zhenglu | Rotchell, Jeanette M. | Shen, Xiaoteng | Li, Qipei | Zhu, Jingmin
Mussels are suggested as bioindicators of marine microplastic pollution. However, they are selective in regards to accumulation of microplastics. To make studies more targeted and comparable, ultimately helping to determine the suitability of the mussel as a bioindicator species for microplastic exposure, we review the published literature that has directly or indirectly demonstrated particle selection in mussels. The reported difference between microplastic levels in mussel tissues and environmental matrices provides evidence for their selective uptake characteristics. Both the organ-specific fate characteristics of microplastics, and the different movement patterns of microplastics in the same organ, show that selective translocation processes take place. The selective elimination is reflected in multiple aspects which include (1) the different characteristics of microplastics in excretion and mussel body; (2) the different retention time of various microplastics in mussels; and (3) the tissue-specific change in the numbers of microplastics during the depuration process. This selectivity is affected by the characteristics of the microplastics, the environmental, or laboratory exposure concentrations, feeding status, and other factors. There are still many research gaps and contradictory viewpoints in this field due to this complexity. The current methodology needs improvement and a breakthrough in standardization.
Show more [+] Less [-]Evaluating the effectiveness of green marketing of socio-economic organizations in reducing environmental pollution Full text
2021
Hojjat Nazari | Sadegh Zibakalam | Mohammad Reza Parvin
The purpose of this study is to measure and evaluate the effectiveness of environmental advertising related to green marketing by organization. In other words, the researcher seeks to find the success rate of environmental advertising in reducing environmental pollution. The type of goal is an application that has been done by descriptive-survey method. A researcher-made questionnaire was used to collect data. The statistical populations of the study were consumers of environmental friendly goods in Tehran. Confirmatory factor analysis method and SPSS, Version21 and AMOS (2016) software were used for data analysis. The results showed that the models for measuring the research variables are appropriate models. Because the value of Ï2 and the value of RMSEA are low and also the values of AGFI, GFI and NFI are greater than 0.9 and the significance level of factor loads is less than 5%, which indicates the significance of the relationship defined in the measurement models. Also, the effect of communication stimuli on the cognitive and emotional response of consumers and then the effect of content stimuli on the cognitive and emotional response of users in this study has the highest influence. However, neither content nor communication stimuli have influenced consumer attitudes.
Show more [+] Less [-]Investigation of physicochemical properties of water in downstream areas of selected dams in Aras catchment and water quality assessment (Case study: Aras catchment in the border area of Iran and Armenia) Full text
2021
Ebrahim Safizadeh | Dariush Karimi | Hamid Reza Gahfarzadeh | Seyed Abbas Pourhashemi
The aim of this study was to evaluate the physicochemical properties of downstream water of Aras river dams. Sampling was performed from early 2018-2019 in selected stations. Heavy metals were measured by atomic absorption spectrometry. Nitrate, nitrite and total dissolved solids concentrations were also measured by spectrophotometer. Concentrations of Ca, Na and K were measured with a Flame Photometer and the rest were measured with specialized devices. The results showed that the lowest electrical conductivity in the measured samples was 0.789 and the highest was 4.346 µs/cm, which basically indicates the high limit of soil and water for irrigation of plants. On the other hand, total solids with 1211 ppm indicate a moderate limit for salinity. Also; regarding pH, the average recorded for the study area is 8.17, which is within the national permissible and standard range of the world health organization. Nitrate and nitrite are both above the permissible and standard range. Potassium is within the permitted and standard range. Calcium, according to the average obtained in the study area (64 ppm) can be said that this parameter is within the allowable and standard range. In the case of lead (0.09 ppb), it can be said that this parameter is within the allowable and standard range. In the case of cadmium (0.8 ppb), it can be said that this parameter is within the allowable and standard range, 3 parameters nitrate, nitrite and TDS have an average higher than the national standard.
Show more [+] Less [-]Removal of Malathion on Carbon using Iron Oxide Nanoparticles (Fe3O4) in Aquatic Environments Full text
2021
Malektaj Eskandari Makvand | Sima Sabzalipour | Mahboobeh Cheraghi | Neda Orak
The development of nanotechnology and the possible entry of nanoparticles into aquatic environments have raised environmental concerns. The present study aimed to investigate the effect of iron oxide nanoparticles (Fe3O4) loaded on carbon to remove malathion in order to evaluate the toxicity potential of nanoparticles in aqueous environments. We examined the characteristics of iron oxide nanoparticles (Fe3O4) using XRD refraction, Fourier irradiated spectroscopy (FTIR), the catalytic activity of iron nanoparticles for activation of persulfate, and malathion decomposition. Moreover, we assessed the influence of effective parameters on this process, such as pH, persulfate concentration, and the number of iron oxide nanoparticles (Fe3O4). The results showed that 82% of malathion was decomposed by the combined process of iron oxide nanoparticles loaded on carbon at pH=5 and 0.4 g of iron nanoparticles in 60 minutes. Additionally, according to the results obtained from the advanced oxidation processes, it was able to optimally remove malathion from the aquatic environment. This study revealed that nanoparticle stabilization technology on activated carbon could be used as an effective, efficient, and fast adsorbent to remove certain contaminants, such as malathion, from aqueous solutions. Although the combination of processes may complicate their analysis and mechanism, the study of this process could be a promising emergence of hybrid processes in water and wastewater treatment. In general, the results of this study relatively indicated that the physicochemical properties of nanoparticles, such as size, shape, surface, general morphology, and chemical composition, in different environmental conditions can significantly affect carbon in removing the malathion
Show more [+] Less [-]Application of Steam Enhanced Extraction method on BTEX contaminated soil in a Nigerian petroleum depot and Automobile workshop sites in Ilorin metropolis, Nigeria. Full text
2021
Ismail Muhibbu-din | Isaac Ayodele
. Benzene, toluene, ethyl benzene and xylene (BTEX) are major causes of contaminated soil. This is due to fuel leakages or spillages, various forms hydrocarbon burning/combustion and land disposal petroleum base oil. Contaminated soil samples were excavated from two different locations within Ilorin metropolis; pipelines and products marketing company, a Nigerian petroleum depot, Ilorin depot and auto mechanic workshop of over ten years. Steam enhanced extraction method was employed through injection of steam to contaminated soil from steam generator into soil pot where contaminated soil was placed. After the remediation process the steam soil samples were taken to the laboratory where the sonication extraction technique was used to extract the contaminants (BTEX) from the steamed soil samples of 30, 60 and 90 minutes respectively. The extract from the steamed soil samples of 30, 60 and 90 minutes were subjected Gas Chromatography fitted with flame ionization detector analysis to determine the exact amount of BTEX removed after remediation process. Pre-treated soil sample of auto mechanics workshop was found to be 4.5004 x 10-1 mg/kg and post-treated soil samples were found to be 1.8164 x10-1 mg/kg, 8.7519 x10-1 mg/kg and 5.7006 x10-2 mg/kg for 30, 60 and 90 minutes respectively after remediation process while Pre-treated soil sample of a Nigerian petroleum depot was found to be 6.6049 x 10-1 mg/kg and post-treated soil samples were found to be 2.9320 x10-1 mg/kg, 1.9855 x10-1 mg/kg and 1.0237 x10-1 mg/kg for 30, 60 and 90 minutes respectively after remediation process
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