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Mytilus spp. as sentinels for monitoring microplastic pollution in Norwegian coastal waters: A qualitative and quantitative study Полный текст
2018
Bråte, Inger Lise N. | Hurley, Rachel | Iversen, Karine | Beyer, Jonny | Thomas, Kevin V. | Steindal, Calin C. | Green, Norman W. | Olsen, Marianne | Lusher, Amy
Mytilus spp. as sentinels for monitoring microplastic pollution in Norwegian coastal waters: A qualitative and quantitative study Полный текст
2018
Bråte, Inger Lise N. | Hurley, Rachel | Iversen, Karine | Beyer, Jonny | Thomas, Kevin V. | Steindal, Calin C. | Green, Norman W. | Olsen, Marianne | Lusher, Amy
Microplastic (MP) contamination is ubiquitous in the environment and many species worldwide have been shown to contain MP. The ecological impact of MP pollution is still unknown, thus there is an urgent need for more knowledge. One key task is to identify species suitable as sentinels for monitoring in key eco-compartments, such as coastal waters. In Norway, mussels (Mytilus spp.) have been monitored for hazardous contaminants through OSPAR since 1981. Norway has the longest coastline in Europe and adding MP to the Norwegian Mussel Watch is therefore important in a European and global context. The present study reports MP data in mussels (332 specimens) collected from multiple sites (n = 15) spanning the whole Norwegian coastline. MPs were detected at all locations, except at one site on the west coast. Among the most surprising findings, mussels from the Barents Sea coastline in the Finnmark region, contained significantly more MPs than mussels from most of the southern part of the country, despite the latter sites being located much closer to major urban areas. Only mussels from a site located very close to Oslo, the capital, contained levels similar to those observed in the remote site in Finnmark. In total an average of 1.5 (±2.3) particles ind⁻¹ and 0.97 (±2.61) particles w.w. g⁻¹ was found. The most common MPs were <1 mm in size, and fibres accounted for 83% of particles identified, although there was inter-site variability. Thirteen different polymeric groups were identified; cellulosic being the most common and black rubbery particles being the second. This study suggests Mytilus spp. are suitable for semi-quantitative and qualitatively monitoring of MPs in coastal waters. However, some uncertainties remain including mussel size as a confounding factor that may influence ingestion, the role of depuration and other fate related processes, and this call for further research.
Показать больше [+] Меньше [-]Mytilus spp. as sentinels for monitoring microplastic pollution in Norwegian coastal waters: A qualitative and quantitative study. | ENEngelskEnglishMytilus spp. as sentinels for monitoring microplastic pollution in Norwegian coastal waters: A qualitative and quantitative study. Полный текст
2018
Bråte, Inger Lise Nerland | Hurley, Rachel | Iversen, Karine | Beyer, Jonny | Thomas, Kevin V | Steindal, Calin Constantin | Green, Norman Whitaker | Olsen, Marianne | Lusher, Amy
Microplastic (MP) contamination is ubiquitous in the environment and many species worldwide have been shown to contain MP. The ecological impact of MP pollution is still unknown, thus there is an urgent need for more knowledge. One key task is to identify species suitable as sentinels for monitoring in key eco-compartments, such as coastal waters. In Norway, mussels (Mytilus spp.) have been monitored for hazardous contaminants through OSPAR since 1981. Norway has the longest coastline in Europe and adding MP to the Norwegian Mussel Watch is therefore important in a European and global context. The present study reports MP data in mussels (332 specimens) collected from multiple sites (n = 15) spanning the whole Norwegian coastline. MPs were detected at all locations, except at one site on the west coast. Among the most surprising findings, mussels from the Barents Sea coastline in the Finnmark region, contained significantly more MPs than mussels from most of the southern part of the country, despite the latter sites being located much closer to major urban areas. Only mussels from a site located very close to Oslo, the capital, contained levels similar to those observed in the remote site in Finnmark. In total an average of 1.5 (±2.3) particles ind−1 and 0.97 (±2.61) particles w.w. g−1 was found. The most common MPs were <1 mm in size, and fibres accounted for 83% of particles identified, although there was inter-site variability. Thirteen different polymeric groups were identified; cellulosic being the most common and black rubbery particles being the second. This study suggests Mytilus spp. are suitable for semi-quantitative and qualitatively monitoring of MPs in coastal waters. However, some uncertainties remain including mussel size as a confounding factor that may influence ingestion, the role of depuration and other fate related processes, and this call for further research.
Показать больше [+] Меньше [-]Mytilus spp. as sentinels for monitoring microplastic pollution in Norwegian coastal waters: A qualitative and quantitative study. Полный текст
2018
Mytilus spp. as sentinels for monitoring microplastic pollution in Norwegian coastal waters: A qualitative and quantitative study. | Mytilus spp. as sentinels for monitoring microplastic pollution in Norwegian coastal waters: A qualitative and quantitative study. Полный текст
2018
Bråte, Inger Lise Nerland | Hurley, Rachel | Iversen, Karine | Beyer, Jonny | Thomas, Kevin V | Steindal, Calin Constantin | Green, Norman Whitaker | Olsen, Marianne | Lusher, Amy
Microplastic (MP) contamination is ubiquitous in the environment and many species worldwide have been shown to contain MP. The ecological impact of MP pollution is still unknown, thus there is an urgent need for more knowledge. One key task is to identify species suitable as sentinels for monitoring in key eco-compartments, such as coastal waters. In Norway, mussels (Mytilus spp.) have been monitored for hazardous contaminants through OSPAR since 1981. Norway has the longest coastline in Europe and adding MP to the Norwegian Mussel Watch is therefore important in a European and global context. The present study reports MP data in mussels (332 specimens) collected from multiple sites (n = 15) spanning the whole Norwegian coastline. MPs were detected at all locations, except at one site on the west coast. Among the most surprising findings, mussels from the Barents Sea coastline in the Finnmark region, contained significantly more MPs than mussels from most of the southern part of the country, despite the latter sites being located much closer to major urban areas. Only mussels from a site located very close to Oslo, the capital, contained levels similar to those observed in the remote site in Finnmark. In total an average of 1.5 (±2.3) particles ind−1 and 0.97 (±2.61) particles w.w. g−1 was found. The most common MPs were <1 mm in size, and fibres accounted for 83% of particles identified, although there was inter-site variability. Thirteen different polymeric groups were identified; cellulosic being the most common and black rubbery particles being the second. This study suggests Mytilus spp. are suitable for semi-quantitative and qualitatively monitoring of MPs in coastal waters. However, some uncertainties remain including mussel size as a confounding factor that may influence ingestion, the role of depuration and other fate related processes, and this call for further research. | publishedVersion
Показать больше [+] Меньше [-]Cephalosporin antibiotics in the aquatic environment: A critical review of occurrence, fate, ecotoxicity and removal technologies Полный текст
2018
Ribeiro, Alyson R. | Sures, Bernd | Schmidt, Torsten C.
Due to their widespread occurrence in the aquatic environment, human and veterinary cephalosporin antibiotics have been studied as water pollutants. In order to characterize environmental risks of this compound class, this review evaluates relevant data about physicochemical properties, occurrence, ecotoxicity and degradation of cephalosporins. Although application of cephalosporins is rather low compared to other antibiotics and their environmental life-time is believed to be short (i.e. days), the available data is insufficient to draw conclusions on their environmental relevance. Few studies concerning the fate of cephalosporins in soil are available, while hydrolysis and photo-degradation are suggested as the main attenuation processes in the aquatic environment. Cephalosporins have been detected in different aqueous matrices in concentrations ranging from 0.30 ng L−1 to 0.03 mg L−1, with sewage and wastewater being the main matrices with positive findings. For wastewater treatment purposes, several technologies have been tested for the abatement of cephalosporins, including photolysis and adsorption. In most cases, the technology employed led to complete or significant removal (>95%) of parental drugs but few authors reported on cephalosporins' metabolites and transformation products. Furthermore, the present ecotoxicological data are insufficient for comprehensive ecological risk quotient calculations. Considering the total of 53 cephalosporins, effective values (EC, LC, NOAEC, NOAEL, etc.) are only available for around 30% of parental drugs and are very scarce for cyanobacteria, which is considered to be the most sensitive group of organisms to antibiotics. Furthermore, it has been demonstrated that cephalosporins' transformation products can be more toxic and more persistent than the parental drugs. Few investigations considering this possibility are available. Consequently, more effort on ecotoxicological data generation and verification of biological inactivation of cephalosporins-related products is needed. Likewise, the lack of natural depletion rates and knowledge gaps on mixture effects for cephalosporins’ degradation and toxicity have to be overcome.
Показать больше [+] Меньше [-]Long-term exposure to ambient PM2.5 associated with fall-related injury in six low- and middle-income countries Полный текст
2018
Guo, Yanfei | Lin, Hualiang | Shi, Yan | Zheng, Yang | Li, Xing | Xiao, Jianpeng | Liu, Tao | Zeng, Weilin | Vaughn, Michael G. | Cummings-Vaughn, Lenise A. | Nelson, Erik J. | Qian, Zhengmin (Min) | Ma, Wenjun | Wu, Fan
Exposure to ambient air pollution has been linked with adverse health outcomes of the circulatory and nervous systems. Given that falls are closely related to circulatory and nervous health, we hypothesize that air pollution may adversely affect fall-related injury. We employed Wave 1 data from 36,662 participants aged ≥50 years in WHO's Study on Global AGEing and Adult Health in six low- and middle-income countries. Ambient annual concentration of PM2.5 was estimated using satellite data. A three-level logistic regression model was applied to examine the long-term association between ambient PM2.5 and the prevalence of fall-related injury, and associated disease burden, as well as the potential effect modification of consumption of fruit and vegetables. Ambient PM2.5 was found to be significantly associated with the risk of fall-related injury. Each 10 μg/m3 increase corresponded to 18% (OR = 1.18, 95% CI: 1.09, 1.28) increase in fall-related injury after adjusting for various covariates. The association was relatively stronger among participants with lower consumption of fruit (OR = 1.22, 95% CI: 1.12, 1.33) than higher consumption (OR = 1.06, 95% CI: 0.92, 1.23), and among those with lower vegetable consumption (OR = 1.18, 95% CI: 1.08, 1.28) than higher consumption (OR = 1.08, 95% CI: 0.91, 1.27). Our study suggests that ambient PM2.5 may be one risk factor for fall-related injury and that higher consumption of fruit and vegetables could alleviate this effect.
Показать больше [+] Меньше [-]Effects of chlortetracycline on the fate of multi-antibiotic resistance genes and the microbial community during swine manure composting Полный текст
2018
Chen, Zhiqiang | Wang, Yao | Wen, Qinxue
Excessive use of antibiotics in breeding industry leads to accumulation of antibiotic residuals and antibiotic resistance genes (ARGs) in environment from improperly treated livestock excrements. Four commonly used veterinary antibiotics including chlortetracycline (CTC), sulfamerazine (SMZ), enrofloxacin (ENR) and erythromycin (ERY) were monitored in the swine manure composting. Co-resistance and cross-resistance effects among relative ARGs, correlations between ARGs and bacterial community under multiple antibiotics residual during the composting were investigated in this research. With CTC addition up to 20 mg/kg, more than 99% of CTC removal was achieved after composting, and most of the other antibiotics can be thoroughly removed as well. The variations in ARGs during the composting were strongly correlated to the compositions of the microbial community, Bacteroides and Sporosarcina were main ARGs carriers in the thermophlic phase. Clostridium Ⅺ, Clostridium sensu stricto, and Pseudoxanthomonas, might spread ARGs in cooling and maturing stage. Most of the tested ARGs in swine manure can be effectively reduced through composting, thus makes the compost products safe for soil fertilization.
Показать больше [+] Меньше [-]DEP and DBP induce cytotoxicity in mouse embryonic stem cells and abnormally enhance neural ectoderm development Полный текст
2018
Yin, Nuoya | Liang, Shengxian | Liang, Shaojun | Hu, Bowen | Yang, Renjun | Zhou, Qunfang | Jiang, Guibin | Faiola, Francesco
Diethyl phthalate (DEP) and dibutyl phthalate (DBP) are two typical small phthalate esters, extensively used in personal care and consumer products. Although previous studies have linked phthalate esters to several health issues, it is still unclear whether they can affects the early stages of embryonic development. In this study, we evaluated the early developmental neurotoxicity as well as the cytotoxicity of DEP and DBP, using mouse embryonic stem cells (mESCs). Our results showed that both DEP and DBP could decrease mESC viability in a dose-dependent manner. Moreover, while DBP could activate the caspase-3/7 enzymes and cause cell membrane damage as well as intracellular ROS accumulation, interestingly DEP treatment only showed stimulation of ROS production. In addition, DEP and DBP treatment at non-cytotoxic concentrations, abnormally altered the expression levels of several vitally important regulators of embryo development. For instance, neural ectoderm markers, such as Pax6, Nestin, Sox1 and Sox3, were significantly up-regulated upon DEP and DBP exposure. In conclusion, our work suggests a potential developmental toxicity of DEP and DBP on mammals, especially for neural ectoderm specification. Our findings help better understand the association between health problems and DEP/DBP exposure and most significantly remind us of the importance of additional health risk tests for these two largely used chemicals.
Показать больше [+] Меньше [-]Lifecycle exposure to perchlorate differentially alters morphology, biochemistry, and transcription as well as sperm motility in Silurana tropicalis frogs Полный текст
2018
Campbell, Diana E.K. | Montgomerie, Robert D. | Langlois, Valérie S.
Perchlorate (ClO4−) contamination has been reported in ground and surface waters across North America. However, few studies have examined the effects of prolonged exposure to this thyroid hormone disrupting chemical, particularly at environmentally relevant concentrations in lower vertebrates, such as amphibians. The aim of this study was to examine the effects of a yearlong chronic exposure to ClO4− in adult male and female Western clawed frogs (Silurana tropicalis). Frogs were spawned and raised from fertilized embryo until sexual maturity in potassium perchlorate (KClO4)-treated water at different concentrations (0, 20, 53, and 107 μg/L). Developmental and reproductive indices – including adult morphology, androgen plasma levels, gonadal thyroid hormone- and sex steroid-related transcript levels, and sperm motility – were evaluated in male and female adult frogs. Female growth (e.g., body mass, snout-vent length, and hind limb length) was significantly reduced following chronic exposure to environmentally relevant concentrations of KClO4 resulting in females with morphometric indices similar to those of control males – indicating potential sex-specific sensitivities to KClO4. Changes to reproductive indices (i.e., plasma androgen levels, gonadal thyroid hormone- and sex steroid-related transcript levels, and sperm motility) were also observed in both sexes and suggest that KClO4 exposure may also have indirect secondary effects on the reproductive axes in male and female adult frogs. These effects were observed at concentrations at or below those reported in surface waters contaminated with ClO4− suggesting that this contaminant may have developmental and reproductive effects post-metamorphosis in natural amphibian populations.
Показать больше [+] Меньше [-]Plasma polymer facilitated magnetic technology for removal of oils from contaminated waters Полный текст
2018
Wahono, Satriyo Krido | Cavallaro, Alex | Vasilev, Krasimir | Mierczynska, Agnieszka
Oil pollution of waters is one of the most serious environmental problems globally. The long half-life and persistence within the environment makes oil particularly toxic and difficult to remediate. There is a significant need for efficient and cost-effective oil recovery technologies to be brought in to practice. In this study, we developed a facile and efficient magnetic separation method. The surface of 316L stainless steel nanoparticles was modified by plasma deposition of 1,7-octadiene and perfluorooctane, producing relatively hydrophobic coatings having water contact angles of 86 and 100°, respectively. Both coatings had high oil removal efficiency (ORE) of >99%. The captured oil could be easily separated by applying an external magnetic force. The ease of material preparation and separation from the water after the oil is captured, and its high ORE is a compelling argument for further development and optimization of the technology to possible utilization into practice. Furthermore, the capacity of plasma polymerization to deliver desired surface properties can extend the application of the technology to removing other chemical and biological contaminants from polluted waters.
Показать больше [+] Меньше [-]Adsorption and regeneration of expanded graphite modified by CTAB-KBr/H3PO4 for marine oil pollution Полный текст
2018
Xu, Congbin | Jiao, Chunlei | Yao, Ruihua | Lin, Aijun | Jiao, Wentao
The cleaning-up of viscous oil spilled in ocean is a global challenge, especially in Bohai, due to its slow current movement and poor self-purification capacity. Frequent oil-spill accidents not only cause severe and long-term damages to marine ecosystems, but also lead to a great loss of valuable resources. To eliminate the environmental pollution of oil spills, an efficient and environment-friendly oil-recovery approach is necessary. In this study,¹expanded graphite (EG) modified by CTAB-KBr/H₃PO₄ was synthesized via composite intercalation agents of CTAB-KBr and natural flake graphite, followed by the activation of phosphoric acid at low temperature. The resultant modified expanded graphite (M-EG) obtained an interconnected and continuous open microstructure with lower polarity surface, more and larger pores, and increased surface hydrophobicity. Due to these characteristics, M-EG exhibited a superior adsorption capacity towards marine oil. The saturated adsorption capacities of M-EG were as large as 7.44 g/g for engine oil, 6.12 g/g for crude oil, 5.34 g/g for diesel oil and 4.10 g/g for gasoline oil in 120min, exceeding the capacity of pristine EG. Furthermore, M-EG maintained good removal efficiency under different adsorption conditions, such as temperature, oil types, and sodium salt concentration. In addition, oils sorbed into M-EG could be recovered either by a simple compression or filtration-drying treatment with a recovery ratio of 58–83%. However, filtration-drying treatment shows better performance in preserving microstructures of M-EG, which ensures the adsorbents can be recycled several times. High removal capability, fast adsorption efficiency, excellent stability and good recycling performance make M-EG an ideal candidate for treating marine oil pollution in practical application.
Показать больше [+] Меньше [-]Environmental and lifestyle factors affecting exposure to polycyclic aromatic hydrocarbons in the general population in a Middle Eastern area Полный текст
2018
Hoseini, Mohammad | Nabizadeh, Ramin | Delgado-Saborit, Juana Maria | Rafiee, Ata | Yaghmaeian, Kamyar | Parmy, Saeid | Faridi, Sasan | Hassanvand, Mohammad Sadegh | Yunesian, Masud | Naddafi, Kazem
The aim of this study was to investigate environmental and lifestyle factors affecting exposure to PAHs in the general population in a large city of the Middle East (Tehran) by measuring urinary monohydroxy polycyclic aromatic hydrocarbons (OH-PAHs) and establishing relationships between PAHs exposure and related factors. Urine samples were collected from 222 randomly chosen subjects who were living in the urban area of Tehran, Iran. Subjects were required to complete a detailed questionnaire aimed to document their personal and sociodemographic information, activities, cooking-related appliances, smoking history/exposure, and consumed foodstuff. Identification and quantification of six OH-PAHs was carried out using a gas chromatography with mass spectrometry (GC-MS). The geometric means for 1-OHP, 1-NAP, 2-NAP, 2-FLU, 9-FLU, and 9-PHE for whole population study were 310, 1220, 3070, 530, 330, and 130 ng/g creatinine, respectively. The two naphthalene metabolites contributed on average 77% of the total concentration of six measured OH-PAHs, followed by the 2-FLU, 1-OHP, 9-FLU, and 9-PHE. The most important predictors of urinary PAHs were consumption of grilled/barbecued foods, smoking, and exposure to environmental tobacco smoking. Water pipe smoking was linked to urinary OH-PAH metabolite in a dose-response function. Residential traffic was also related with OH-PAH metabolite concentrations. Other factors including gender, age, exposure to common house insecticides, open burning, and candle burning were found to be statistically associated with the urinary levels of some OH-PAHs. High exposure to PAHs among general population in Middle Eastern large cities and its associated health implications calls for public health measures to reduce PAHs exposure.
Показать больше [+] Меньше [-]Mixed method approach to assess atmospheric nitrogen deposition in arid and semi-arid ecosystems Полный текст
2018
Cook, Elizabeth M. | Sponseller, Ryan | Grimm, Nancy B. | Hall, Sharon J.
Arid and semi-arid ecosystems (aridlands) cover a third of Earth's terrestrial surface and contain organisms that are sensitive to low level atmospheric pollutants. Atmospheric nitrogen (N) inputs to aridlands are likely to cause changes in plant community composition, fire frequency, and carbon cycling and storage. However, few studies have documented long-term rates of atmospheric N inputs in aridlands because dry deposition is technically difficult to quantify, and extensive sampling is needed to capture fluxes with spatially and temporally heterogeneous rainfall patterns. Here, we quantified long-term spatial and temporal patterns of inorganic N deposition in protected aridland ecosystems across an extensive urban-rural gradient using multiple sampling methods. We compared long-term rates of N deposition from ion-exchange resin (IER) collectors (bulk and throughfall, 2006–2015), wet-dry bucket collectors (2006–2015), and dry deposition from the inferential method using passive samplers (2010–2012). From mixed approaches with IER collectors and inferential methods, we determined that 7.2 ± 0.4 kgNha⁻¹y⁻¹ is deposited to protected Sonoran Desert within metropolitan Phoenix, Arizona and 6.1 ± 0.3 kgNha⁻¹y⁻¹ in nearby desert ecosystems. Regional scale models overestimated deposition rates for our sampling period by 60% and misidentified hot spots of deposition across the airshed. By contrast, the easy-deployment IER throughfall collectors showed minimal spatial variation across the urban-rural gradient and underestimated deposition fluxes by 54%, largely because of underestimated dry deposition in throughfall. However, seasonal sampling of the IER collectors over 10 years allowed us to capture significant seasonal variation in N deposition and the importance of precipitation timing. These results, derived from the longest, spatially and temporally explicit dataset in drylands, highlight the need for long-term, mixed methods to estimate atmospheric nutrient enrichment to aridlands in a rapidly changing world.
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