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Characteristics and Health Risk of BTEX at Selected Different Microenvironments in an Industrial-Urban Area, Iran 全文
2019
Tarassoli, A. | Esmaili Sari, A. | Bahramifar, N.
The present study monitors BTEX concentration in outdoor and indoor air of eight different microenvironments during summer 2017 and winter 2018 at Asaloyeh city, Iran's energy capital. It samples BTEX compounds by charcoal tubes, analyzing the samples by means of a gas chromatograph with a flame ionization detector. According to the obtained results, outdoor concentrations of BTEX have been higher than the indoor ones, for both seasons, with the highest outdoor and indoor BTEX being 21.70 and 18.59 μg/m3, respectively. Toluene has been the most abundant substance, among the investigated BTEX in all sampling points. Based on the MIR scale, m, p-xylene is the most dominant contributor to ozone formation potential among BTEX species. Indoor to outdoor (I/O) ratios of BTEX compounds range from 0.53 to 0.88 and 0.41 to 0.77 in winter and summer, respectively. The cumulative hazard index (HI) is within an acceptable range. The LTCR value of benzene concentration, obtained, exceeds the value of 1.0E-06, recommended by USEPA. Sensitivity analysis shows that benzene concentration, exposure duration, and inhalation rate have a greater impact on health risk assessment.
显示更多 [+] 显示较少 [-]Extraction and Recovery of Polycyclic Aromatic Hydrocarbons in Petroleum Contaminated Soils Using Supercritical Water by Response Surface Methodology 全文
2019
Motamedimehr, Sh. | Gitipour, S.
Finding an environment-friendly and affordable method to remove contaminated soils from Polycyclic Aromatic Hydrocarbons (PAHs) has now become an attractive field for researchers, with super-critical fluid extraction being an innovative process in the field of contaminated soil treatment. Extraction with super-critical fluid is a simple and rapid extraction process that uses super-critical fluids as solvents. The present study has investigated the extraction of contaminated soil with Polycyclic Aromatic Hydrocarbons (PAHs) by means of batch supercritical water reactor, employing variables like pressure (100–300 bar), temperature (60–140 ◦C), residence time (0.5–3 hours), and base, acidic, and neutral pH values. In order optimize the process parameters, Response Surface Methodology (RSM) has been used. Results show that removal efficiency of PAHs is between 82%-100%, where the highest PAHs removal efficiency (100%) has been observed in Test No. 22, with a pressure of 300 bars, temperature of 500°C, acidic pH equal to 5, and duration of 3 hours. In addition, the lowest removal efficiency of these compounds (82%) has been obtained in Test No. 26, with a pressure of 300 bars, temperature of 350°C, base pH of 9, and duration of half an hour. According to the results from this study, it has become clear that residence time is the most important and most effective parameter for removing PAHs from contaminated soil. Afterwards, temperature and pH are most influential with pressure showing the least effect. Using supercritical water method in appropriate conditions can eliminate more than 99% of aromatic contamination.
显示更多 [+] 显示较少 [-]Estimation of the economic loss due to irrigation water use inefficiency in Tunisia 全文
2019
Chebil, Ali | Souissi, Asma | Frija, Aymen | Stambouli, Talel
Estimation of the economic loss due to irrigation water use inefficiency in Tunisia 全文
2019
Chebil, Ali | Souissi, Asma | Frija, Aymen | Stambouli, Talel
The main objective of this study is to estimate the total economic loss due to inefficient use of irrigation water in Tunisia. Several approaches have been used for this purpose. The optimal level of water application for different crops is calculated using the actual crop evapotranspiration which is based on FAO-56 method. The residual imputation and yield comparison methods have been used to estimate the economic value of irrigation water for different irrigated crops in different bioclimatic areas. For the empirical analysis, primary data were obtained from a series of surveys that covered 78% of the total irrigated areas and were collected within the framework of the BVirtual Water and Food Security in Tunisia project^ (2013–2015). Secondary data about land distribution of crops in Tunisia were taken from the Ministry of Agriculture (2016). Around 724 farms were randomly sampled considering their bioclimatic area, farm type, and production system. The survey included the main 20 crops produced in Tunisia. Results show that most of farmers are either under or over utilizing irrigation water. The value of total direct economic losses, at the country level, of both types of water inefficiencies, was estimated to around 470 million Tunisian Dinars. Therefore, an improvement of water use efficiency at field level through dissemination of information/knowledge on irrigation scheduling and crop water requirements by extension services to farmers is needed to reduce this huge economic loss, reach higher sustainability in water use and improve food security.
显示更多 [+] 显示较少 [-]Estimation of the economic loss due to irrigation water use inefficiency in Tunisia 全文
2019
Chebil, Ali | Souissi, Asma | Frija, Aymen | Stambouli, Talel
The main objective of this study is to estimate the total economic loss due to inefficient use of irrigation water in Tunisia. Several approaches have been used for this purpose. The optimal level of water application for different crops is calculated using the actual crop evapotranspiration which is based on FAO-56 method. The residual imputation and yield comparison methods have been used to estimate the economic value of irrigation water for different irrigated crops in different bioclimatic areas. For the empirical analysis, primary data were obtained from a series of surveys that covered 78% of the total irrigated areas and were collected within the framework of the “Virtual Water and Food Security in Tunisia project” (2013–2015). Secondary data about land distribution of crops in Tunisia were taken from the Ministry of Agriculture (2016). Around 724 farms were randomly sampled considering their bioclimatic area, farm type, and production system. The survey included the main 20 crops produced in Tunisia. Results show that most of farmers are either under or over utilizing irrigation water. The value of total direct economic losses, at the country level, of both types of water inefficiencies, was estimated to around 470 million Tunisian Dinars. Therefore, an improvement of water use efficiency at field level through dissemination of information/knowledge on irrigation scheduling and crop water requirements by extension services to farmers is needed to reduce this huge economic loss, reach higher sustainability in water use and improve food security.
显示更多 [+] 显示较少 [-]Relationships between Pb, As, Cr, and Cd in individual cows’ milk and milk composition and heavy metal contents in water, silage, and soil 全文
2019
Zhou, Xuewei | Zheng, N. | Su, C. | Wang, J. | Soyeurt, Hélène
Relationships between Pb, As, Cr, and Cd in individual cows’ milk and milk composition and heavy metal contents in water, silage, and soil 全文
2019
Zhou, Xuewei | Zheng, N. | Su, C. | Wang, J. | Soyeurt, Hélène
peer reviewed | This works estimated the relationships between heavy metals in milk from individual cows, drinking water, silage and soil as well as the links between those elements and the milk composition. © 2019Various industrial activities lead to environmental pollution by heavy metals. Toxic heavy metals enter the food chain of dairy cows through feed and water, then transferred into milk. This study investigated the correlations of heavy metal contents between individual cows’ milk, water, silage and soil. The relationships between heavy metal contents in individual cows’ milk with milk protein, fat, lactose, solid nonfat (SNF), and total solids (TS) were analysed. Concentrations of Pb, As, Cr, and Cd in milk, silage and water were measured by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Lead, Cr, and Cd in soil were measured by Atomic Absorption Spectrometry (AAS), and As was detected by Atomic Fluorescence Spectrometry (AFS). One-way non-parametric tests and Spearman correlation analyses were performed using SAS 9.4 software. Levels of Pb and Cd in milk from the unpolluted area were significantly lower (P < 0.01) than those from industrial area. Significantly higher (P < 0.01) As residue was recorded in milk from unpolluted area. Positive correlation of Pb was observed between milk and silage, and As in milk was positively correlated with As in water. Content of As in milk was slightly (r = 0.09) correlated with As in silage, even though strong positive correlation (r = 0.78) was observed between silage and water. Positive correlations were observed for Cr and Cd between milk and silage, as well as milk and soil. Positive correlations were observed in Pb-protein, Cr-protein, and Cd-lactose; other positive correlation coefficients were nearly equal to zero. The results suggest that industrial activities lead to possible Pb and Cd contamination in milk. Drinking water could be the main source of As contamination in cows. No clear relationship was found between milk composition and heavy metals contents in milk. Water and soil on the farm had a partial contribution to heavy metal contamination in milk. © 2019 | Project of Risk Assessment on Raw Milk (GJFP2019008)
显示更多 [+] 显示较少 [-]Relationships between Pb, As, Cr, and Cd in individual cows’ milk and milk composition and heavy metal contents in water, silage, and soil 全文
2019
Zhou, Xuewei | Zheng, Nan | Su, Chuanyou | Wang, Jiaqi | Soyeurt, Hélène
Various industrial activities lead to environmental pollution by heavy metals. Toxic heavy metals enter the food chain of dairy cows through feed and water, then transferred into milk. This study investigated the correlations of heavy metal contents between individual cows’ milk, water, silage and soil. The relationships between heavy metal contents in individual cows’ milk with milk protein, fat, lactose, solid nonfat (SNF), and total solids (TS) were analysed. Concentrations of Pb, As, Cr, and Cd in milk, silage and water were measured by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Lead, Cr, and Cd in soil were measured by Atomic Absorption Spectrometry (AAS), and As was detected by Atomic Fluorescence Spectrometry (AFS). One-way non-parametric tests and Spearman correlation analyses were performed using SAS 9.4 software. Levels of Pb and Cd in milk from the unpolluted area were significantly lower (P < 0.01) than those from industrial area. Significantly higher (P < 0.01) As residue was recorded in milk from unpolluted area. Positive correlation of Pb was observed between milk and silage, and As in milk was positively correlated with As in water. Content of As in milk was slightly (r = 0.09) correlated with As in silage, even though strong positive correlation (r = 0.78) was observed between silage and water. Positive correlations were observed for Cr and Cd between milk and silage, as well as milk and soil. Positive correlations were observed in Pb-protein, Cr-protein, and Cd-lactose; other positive correlation coefficients were nearly equal to zero. The results suggest that industrial activities lead to possible Pb and Cd contamination in milk. Drinking water could be the main source of As contamination in cows. No clear relationship was found between milk composition and heavy metals contents in milk. Water and soil on the farm had a partial contribution to heavy metal contamination in milk.
显示更多 [+] 显示较少 [-]A Bayesian network approach for the identification of relationships between drivers of chlordecone bioaccumulation in plants 全文
2019
Liber, Yohan | Cornet, Denis | Tournebize, Régis | Feidt, Cyril | Mahieu, Maurice | Laurent, François | Bedell, Jean-Philippe
Plants were sampled from four different types of chlordecone-contaminated land in Guadeloupe (West Indies). The objective was to investigate the importance of biological and agri-environmental parameters in the ability of plants to bioaccumulate chlordecone. Among the plant traits studied, only the growth habit significantly affected chlordecone transfer, since prostrate plants concentrated more chlordecone than erect plants. In addition, intensification of land use has led to a significant increase in the amount of chlordecone absorbed by plants. The use of Bayesian networks uncovers some hypothesis and identifies paths for reflection and possible studies to identify and quantify relationships that explain our data.
显示更多 [+] 显示较少 [-]Plasma concentrations of organohalogenated contaminants in white-tailed eagle nestlings – The role of age and diet 全文
2019
Løseth, Mari Engvig | Briels, Nathalie | Eulaers, Igor | Nygård, Torgeir | Malarvannan, Govindan | Poma, Giulia | Covaci, Adrian | Herzke, Dorte | Bustnes, Jan Ove | Lepoint, Gilles | Jenssen, Bjørn Munro | Jaspers, Veerle
Plasma concentrations of organohalogenated contaminants in white-tailed eagle nestlings – The role of age and diet 全文
2019
Løseth, Mari Engvig | Briels, Nathalie | Eulaers, Igor | Nygård, Torgeir | Malarvannan, Govindan | Poma, Giulia | Covaci, Adrian | Herzke, Dorte | Bustnes, Jan Ove | Lepoint, Gilles | Jenssen, Bjørn Munro | Jaspers, Veerle
Concentrations of organohalogenated contaminants (OHCs) can show significant temporal and spatial variation in the environment and wildlife. Most of the variation is due to changes in use and production, but environmental and biological factors may also contribute to the variation. Nestlings of top predators are exposed to maternally transferred OHCs in the egg and through their dietary intake after hatching. The present study investigated spatial and temporal variation of OHCs and the role of age and diet on these variations in plasma of Norwegian white-tailed eagle (Haliaeetus albicilla) nestlings. The nestlings were sampled at two locations, Smøla and Steigen, in 2015 and 2016. The age of the nestlings was recorded (range: 44 - 87 days old) and stable carbon and nitrogen isotopes (δ13C and δ15N) were applied as dietary proxies for carbon source and trophic position, respectively. In total, 14 polychlorinated biphenyls (PCBs, range: 0.82 - 59.05 ng/mL), 7 organochlorinated pesticides (OCPs, range: 0.89 - 52.19 ng/mL), 5 polybrominated diphenyl ethers (PBDEs, range: 0.03 - 2.64 ng/mL) and 8 perfluoroalkyl substances (PFASs, range: 4.58 - 52.94 ng/mL) were quantified in plasma samples from each location and year. The OHC concentrations, age and dietary proxies displayed temporal and spatial variations. The age of the nestlings was indicated as the most important predictor for OHC variation as the models displayed significantly decreasing plasma concentrations of PCBs, OCPs, and PBDEs with increasing age, while concentrations of PFASs were significantly increasing with age. Together with age, the variations in PCB, OCP and PBDE concentrations were also explained by δ13C and indicated decreasing concentrations with a more marine diet. Our findings emphasise age and diet as important factors to consider when investigating variations in plasma OHC concentrations in nestlings. | acceptedVersion
显示更多 [+] 显示较少 [-]Plasma concentrations of organohalogenated contaminants in white-tailed eagle nestlings – The role of age and diet 全文
2019
Løseth, Mari Engvig | Briels, Nathalie | Eulaers, Igor | Nygård, Torgeir | Malarvannan, Govindan | Poma, Giulia | Covaci, Adrian | Herzke, Dorte | Bustnes, Jan Ove | Lepoint, Gilles | Jenssen, Bjørn Munro | Jaspers, Veerle L.B.
Concentrations of organohalogenated contaminants (OHCs) can show significant temporal and spatial variation in the environment and wildlife. Most of the variation is due to changes in use and production, but environmental and biological factors may also contribute to the variation. Nestlings of top predators are exposed to maternally transferred OHCs in the egg and through their dietary intake after hatching. The present study investigated spatial and temporal variation of OHCs and the role of age and diet on these variations in plasma of Norwegian white-tailed eagle (Haliaeetus albicilla) nestlings. The nestlings were sampled at two locations, Smøla and Steigen, in 2015 and 2016. The age of the nestlings was recorded (range: 44 – 87 days old) and stable carbon and nitrogen isotopes (δ¹³C and δ¹⁵N) were applied as dietary proxies for carbon source and trophic position, respectively. In total, 14 polychlorinated biphenyls (PCBs, range: 0.82 – 59.05 ng/mL), 7 organochlorinated pesticides (OCPs, range: 0.89 – 52.19 ng/mL), 5 polybrominated diphenyl ethers (PBDEs, range: 0.03 – 2.64 ng/mL) and 8 perfluoroalkyl substances (PFASs, range: 4.58 – 52.94 ng/mL) were quantified in plasma samples from each location and year. The OHC concentrations, age and dietary proxies displayed temporal and spatial variations. The age of the nestlings was indicated as the most important predictor for OHC variation as the models displayed significantly decreasing plasma concentrations of PCBs, OCPs, and PBDEs with increasing age, while concentrations of PFASs were significantly increasing with age. Together with age, the variations in PCB, OCP and PBDE concentrations were also explained by δ¹³C and indicated decreasing concentrations with a more marine diet. Our findings emphasise age and diet as important factors to consider when investigating variations in plasma OHC concentrations in nestlings.
显示更多 [+] 显示较少 [-]Plasma concentrations of organohalogenated contaminants in white-tailed eagle nestlings – The role of age and diet 全文
2019
Løseth, M. E. | Briels, N. | Eulaers, I. | Nygård, T. | Malarvannan, G. | Poma, G. | Covaci, A. | Herzke, D. | Bustnes, J. O. | Lepoint, Gilles | Jenssen, B. M. | Jaspers, V. L. B.
peer reviewed | Concentrations of organohalogenated contaminants (OHCs) can show significant temporal and spatial variation in the environment and wildlife. Most of the variation is due to changes in use and production, but environmental and biological factors may also contribute to the variation. Nestlings of top predators are exposed to maternally transferred OHCs in the egg and through their dietary intake after hatching. The present study investigated spatial and temporal variation of OHCs and the role of age and diet on these variations in plasma of Norwegian white-tailed eagle (Haliaeetus albicilla) nestlings. The nestlings were sampled at two locations, Smøla and Steigen, in 2015 and 2016. The age of the nestlings was recorded (range: 44 – 87 days old) and stable carbon and nitrogen isotopes (δ13C and δ15N) were applied as dietary proxies for carbon source and trophic position, respectively. In total, 14 polychlorinated biphenyls (PCBs, range: 0.82 – 59.05 ng/mL), 7 organochlorinated pesticides (OCPs, range: 0.89 – 52.19 ng/mL), 5 polybrominated diphenyl ethers (PBDEs, range: 0.03 – 2.64 ng/mL) and 8 perfluoroalkyl substances (PFASs, range: 4.58 – 52.94 ng/mL) were quantified in plasma samples from each location and year. The OHC concentrations, age and dietary proxies displayed temporal and spatial variations. The age of the nestlings was indicated as the most important predictor for OHC variation as the models displayed significantly decreasing plasma concentrations of PCBs, OCPs, and PBDEs with increasing age, while concentrations of PFASs were significantly increasing with age. Together with age, the variations in PCB, OCP and PBDE concentrations were also explained by δ13C and indicated decreasing concentrations with a more marine diet. Our findings emphasise age and diet as important factors to consider when investigating variations in plasma OHC concentrations in nestlings. © 2018 Elsevier Ltd | 230465
显示更多 [+] 显示较少 [-]Accumulation and toxicity of monoaromatic petroleum hydrocarbons in early life stages of cod and haddock 全文
2019
Sørensen, Lisbet | Hansen, Bjørn Henrik | Farkas, Julia | Donald, Carey | Robson, William | Tonkin, Andrew | Meier, Sonnich | Rowland, Steven J
Accumulation and toxicity of monoaromatic petroleum hydrocarbons in early life stages of cod and haddock 全文
2019
Sørensen, Lisbet | Hansen, Bjørn Henrik | Farkas, Julia | Donald, Carey | Robson, William | Tonkin, Andrew | Meier, Sonnich | Rowland, Steven J
A multitude of recent studies have documented the detrimental effects of crude oil exposure on early life stages of fish, including larvae and embryos. While polycyclic aromatic hydrocarbons (PAHs), particularly alkyl PAHs, are often considered the main cause of observed toxic effects, other crude oil derived organic compounds are usually overlooked. In the current study, comprehensive two-dimensional gas chromatography coupled to mass spectrometry was applied to investigate the body burden of a wide range of petrogenic compounds in Atlantic haddock (Melanogrammus aeglefinus) and cod (Gadus morhua) embryos that had been exposed to sublethal doses of dispersed crude oil. Several groups of alkylated monoaromatic compounds (e.g. alkyl tetralins, indanes and alkyl benzenes), as well as highly alkylated PAHs, were found to accumulate in the fish embryos upon crude oil exposure. To investigate the toxicity of the monoaromatic compounds, two models (1-isopropyl-4-methyltetralin and 1-isopropyl-4-methylindane) were synthesized and shown to bioaccumulate and cause delayed hatching in developing embryos. Minor developmental effects, including craniofacial and jaw deformations and pericardial edemas, were also observed at the highest studied concentrations of the alkylindane. | acceptedVersion
显示更多 [+] 显示较少 [-]Accumulation and toxicity of monoaromatic petroleum hydrocarbons in early life stages of cod and haddock 全文
2019
Sørensen, Lisbet | Hansen, Bjørn Henrik | Farkas, Julia | Donald, Carey | Robson, William | Tonkin, Andrew | Meier, Sonnich | Rowland, Steven J
A multitude of recent studies have documented the detrimental effects of crude oil exposure on early life stages of fish, including larvae and embryos. While polycyclic aromatic hydrocarbons (PAHs), particularly alkyl PAHs, are often considered the main cause of observed toxic effects, other crude oil derived organic compounds are usually overlooked. In the current study, comprehensive two-dimensional gas chromatography coupled to mass spectrometry was applied to investigate the body burden of a wide range of petrogenic compounds in Atlantic haddock (Melanogrammus aeglefinus) and cod (Gadus morhua) embryos that had been exposed to sublethal doses of dispersed crude oil. Several groups of alkylated monoaromatic compounds (e.g. alkyl tetralins, indanes and alkyl benzenes), as well as highly alkylated PAHs, were found to accumulate in the fish embryos upon crude oil exposure. To investigate the toxicity of the monoaromatic compounds, two models (1-isopropyl-4-methyltetralin and 1-isopropyl-4-methylindane) were synthesized and shown to bioaccumulate and cause delayed hatching in developing embryos. Minor developmental effects, including craniofacial and jaw deformations and pericardial edemas, were also observed at the highest studied concentrations of the alkylindane. | acceptedVersion
显示更多 [+] 显示较少 [-]Accumulation and toxicity of monoaromatic petroleum hydrocarbons in early life stages of cod and haddock 全文
2019
Sørensen, Lisbet | Hansen, Bjørn Henrik | Farkas, Júlia | Donald, Carey E. | Robson, William J. | Tonkin, Andrew M. | Meier, Sonnich | Rowland, Steven J.
A multitude of recent studies have documented the detrimental effects of crude oil exposure on early life stages of fish, including larvae and embryos. While polycyclic aromatic hydrocarbons (PAHs), particularly alkyl PAHs, are often considered the main cause of observed toxic effects, other crude oil derived organic compounds are usually overlooked. In the current study, comprehensive two-dimensional gas chromatography coupled to mass spectrometry was applied to investigate the body burden of a wide range of petrogenic compounds in Atlantic haddock (Melanogrammus aeglefinus) and cod (Gadus morhua) embryos that had been exposed to sublethal doses of dispersed crude oil. Several groups of alkylated monoaromatic compounds (e.g. alkyl tetralins, indanes and alkyl benzenes), as well as highly alkylated PAHs, were found to accumulate in the fish embryos upon crude oil exposure. To investigate the toxicity of the monoaromatic compounds, two models (1-isopropyl-4-methyltetralin and 1-isopropyl-4-methylindane) were synthesized and shown to bioaccumulate and cause delayed hatching in developing embryos. Minor developmental effects, including craniofacial and jaw deformations and pericardial edemas, were also observed at the highest studied concentrations of the alkylindane.
显示更多 [+] 显示较少 [-]Using mussel as a global bioindicator of coastal microplastic pollution 全文
2019
Li, Jiana | Lusher, Amy L | Rotchell, Jeanette M. | Deudero, Salud | Turra, Alexander | Bråte, Inger Lise N | Sun, Chengjun | Hossain, M. Shahadat | Li, Qipei | Kolandhasamy, Prabhu | Shi, Huahong
Using mussel as a global bioindicator of coastal microplastic pollution 全文
2019
Li, Jiana | Lusher, Amy L | Rotchell, Jeanette M. | Deudero, Salud | Turra, Alexander | Bråte, Inger Lise N | Sun, Chengjun | Hossain, M. Shahadat | Li, Qipei | Kolandhasamy, Prabhu | Shi, Huahong
Embargo until 09 October 2020 | The ubiquity and high bioavailability of microplastics have an unknown risk on the marine environment. Biomonitoring should be used to investigate biotic impacts of microplastic exposure. While many studies have used mussels as indicators for marine microplastic pollution, a robust and clear justification for their selection as indicator species is still lacking. Here, we review published literature from field investigations and laboratory experiments on microplastics in mussels and critically discuss the suitability and challenges of mussels as bioindicator for microplastic pollution. Mussels are suitable bioindicator for microplastic pollution because of their wide distribution, vital ecological niches, susceptibility to microplastic uptake and close connection with marine predators and human health. Field investigations highlight a wide occurrence of microplastics in mussels from all over the world, yet their abundance varies enormously. Problematically, these studies are not comparable due to the lack of a standardized approach, as well as temporal and spatial variability. Interestingly, microplastic abundance in field-collected mussels is closely related to human activity, and there is evidence for a positive and quantitative correlation between microplastics in mussels and surrounding waters. Laboratory studies collectively demonstrate that mussels may be good model organisms in revealing microplastic uptake, accumulation and toxicity. Consequently, we propose the use of mussels as target species to monitor microplastics and call for a uniform, efficient and economical approach that is suitable for a future large-scale monitoring program. | acceptedVersion
显示更多 [+] 显示较少 [-]Microplastics in wild mussels (Mytilus spp.) from the north coast of Spain 全文
2019
Pablo Reguera | Lucía Viñas | Jesús Gago
Microplastic content (MPs) in mussels (Mytilus spp.) from two areas of the north coast of Spain was measured for the first time. Additionally, a comparison of microplastic levels observed in mussels digested with nitric acid and with potassium hydroxide was carried out. The average microplastic concentration in mussels digested with nitric acid was significantly lower than that observed in mussels digested with potassium hydroxide (p < 0.05). The average concentration of microplastics in mussels from the Cantabrian Sea (2.55±2.80 MPs g–1 WW) was slightly higher than that in mussels from the Ria of Vigo (1.59±1.28 MPs g–1 WW). Both in the Ria of Vigo and in the Cantabrian Sea the observed pattern of pollution was fitted to the one expected. Consequently, mussels have been confirmed as suitable sentinel organisms for microplastic pollution.
显示更多 [+] 显示较少 [-]Sources and fate of plastic particles in northern European coastal waters 全文
2019
Karlsson, Therese M.
Plastics are integral parts of our lives and have allowed for important technological leaps within society. However, an unwanted consequence of our current consumption of plas-tics is marine plastic pollution and in order to reduce its impact we need to understand its sources and fate patterns. It is a threefold challenge as it requires suitable methodology, as well as in-depth studies of sources and the various processes that affect the fate of plas-tics. Based on comprehensive tests and evaluations, this thesis provides recommendations on suitable methodologies for sampling, extraction and identification. To further improve the understanding of the fate of plastics in the ocean, in-situ experiments related to oxida-tion and biofouling were performed. Moreover, the distributions of plastic pellets were mapped in a case study area, through field studies and calculations, to understand the spread from local point sources. The results show that floating plastics are prone to beaching and it is concluded that although plastics can be subject to long-range transport, the majority of the pollutants will be found close to the point of release. The studies also show that most floating plastics will eventually sink, due to biofouling and degradation. To provide information on diffuse sources, the evaluated methods were then applied to analyze surface waters, sediment, biota and beach materials. Most microplastics (53-100%) found in the different surveys were identified as fragments of polyethylene, poly-propylene and expanded polystyrene. Since most of the microplastics therefore stem from macroplastics, any attempt to address microplastic pollution needs to have a strong focus on macroplastics. Additionally, pellets and fluff were often encountered and specific point sources related to the production of plastics were examined in an interdisciplinary case study. The study showed continuous spills of plastic pellets associated with production, transportation and storage. The study furthermore illustrated that although there is a legal framework in place, it is not being adequately enforced, which has resulted in limited re-sponsibility and accountability for the involved actors. The studies related to fate process-es illustrate why attempts to decrease plastic pollution need to be focused as close to the source as possible, since that is where prevention and mitigation measures will be most efficient. Furthermore, the results from the field studies are crucial to consider for solu-tion-oriented initiatives. They provide important insights regarding sources and fate of plastic particles, showing that in order to decrease microplastic pollution the main focus needs to be on larger plastics and how we use them. This means working actively to de-crease waste streams through a lower level of consumption, while simultaneously improv-ing waste management strategies to prevent leakage. The increasing interest from multiple stakeholders in academia, amongst policy makers and in the civil society also emphasizes the need for empirical data and clear communication to avoid discrepancies between the perceived and the actual sources and fate of floating plastic particles.
显示更多 [+] 显示较少 [-]Microplastics in wild mussels (Mytilus sp.) from the north coast of Spain 全文
2019
Reguera, P. | Viñas, Lucía | Gago, Jesús
Microplastic content (MPs) in mussels (Mytilus spp.) from two areas of the north coast of Spain was measured for the first time. Additionally, a comparison of microplastic levels observed in mussels digested with nitric acid and with potassium hydroxide was carried out. The average microplastic concentration in mussels digested with nitric acid was significantly lower than that observed in mussels digested with potassium hydroxide (p<0.05). The average concentration of microplastics in mussels from the Cantabrian Sea (2.55±2.80 MPs g–1 WW) was slightly higher than that in mussels from the Ria of Vigo (1.59±1.28 MPs g–1 WW). Both in the Ria of Vigo and in the Cantabrian Sea the observed pattern of pollution was fitted to the one expected. Consequently, mussels have been confirmed as suitable sentinel organisms for microplastic pollution | Sí
显示更多 [+] 显示较少 [-]Characterization and classification of the compositional quality of milk from river buffaloes (Bubalus bubalis) and cows (Bos spp.) in Colombia 全文
2019
Barragán Hernández, W. A. | Mahecha Ledesma, L. | Angulo Arizala, J. | Olivera Angel, M.
The aim of this study was to classify and characterize the compositional quality of milk from river buffaloes (Bubalus bubalis) and cows (Bos spp.) in Colombia based on the fat, protein, and total solid (TS) contents. Using a hierarchical procedure, data on milk from river buffaloes (n = 7,726) and cows (n = 49,330) were filtered and subjected to cluster analysis in order to generate three groups: Normal (N), High quality (HQ) and Poor Quality (PQ). The categorized database was then randomly separated into two sets (training and validation) and a discriminant analysis was applied. In total, 37.3% of river buffalo milk samples were classified as N (6.80% fat, 4.34% protein, and 16.80% TS), 13% as HQ (9.41% fat, 4.93% protein, and 19.50% TS), and 43.7% as PQ (3.95% fat, 3.92% protein, and 13.7% TS). In contrast, 41.8% of cow milk samples were classified as N (3.64% fat, 3.37% protein, 12.42% TS), 41.2% as PQ (2.71% fat, 3.08% protein, and 10.6% TS), and 16.9% as HQ (5.46% fat, 4.01% protein, and 14.82% TS). The discriminant models for both river buffalo and cow milk were able to classify milk in the N and PQ groups with >90% accuracy, and that in the HQ group with >85% accuracy. | Universidad de Antioquia - UdeA | Ganadería bovina
显示更多 [+] 显示较少 [-]Microplastics in wild mussels (Mytilus spp.) from the north coast of Spain | Microplásticos en mejillones silvestres (Mytilus spp.) de la costa del norte de España 全文
2019
Reguera, Pablo | Viñas, Lucía | Gago, Jesús
Microplastic content (MPs) in mussels (Mytilus spp.) from two areas of the north coast of Spain was measured for the first time. Additionally, a comparison of microplastic levels observed in mussels digested with nitric acid and with potassium hydroxide was carried out. The average microplastic concentration in mussels digested with nitric acid was significantly lower than that observed in mussels digested with potassium hydroxide (p < 0.05). The average concentration of microplastics in mussels from the Cantabrian Sea (2.55±2.80 MPs g–1 WW) was slightly higher than that in mussels from the Ria of Vigo (1.59±1.28 MPs g–1 WW). Both in the Ria of Vigo and in the Cantabrian Sea the observed pattern of pollution was fitted to the one expected. Consequently, mussels have been confirmed as suitable sentinel organisms for microplastic pollution. | Se midió por primera vez el contenido en microplásticos (MPs) presente en mejillones (Mytilus spp.) procedentes de dos áreas de la costa del norte de España. Además, se llevó a cabo una comparación de los niveles de microplásticos observados en mejillones digeridos con ácido nítrico y con hidróxido de potasio. La concentración promedio de microplásticos que se observó en los mejillones digeridos con ácido nítrico fue significativamente inferior a la observada en los mejillones digeridos con hidróxido de potasio (p
显示更多 [+] 显示较少 [-]Effect of pollen sources on yield oil extraction and fatty acid profile of the date seed (Phoenix dactylifera L.) cultivar Medjool from Mexico | Efecto de las fuentes de polen sobre el rendimiento en la extracción de aceite y perfil de ácidos grasos de las semillas de dátil (Phoenix dactylifera L.) cultivar Medjool de México 全文
2019
García-González, C. | Salomón-Torres, R. | Montero-Alpírez, G. | Chávez-Velasco, D. | Ortiz-Uribe, N. | Ruiz-Ortiz, N. S. | Coronado-Ortega, M. A. | Curiel-Alvarez, M. A.
The present investigation aimed to assess the effect of pollen sources on the mass, dimension, oil content and fatty acid profile of the seeds from female palms of the Medjool date cultivar. The palms were pollinated with Deglet Noor, Khadrawy, Medjool and Zahidi cultivars. In addition, three palms were pollinated as the treatment control. The fatty acids were evaluated by gas chromatography-mass spectrometry. The surface morphology of date seed powder was examined using SEM, before and after n-hexane interaction. The seeds of the Medjool treatment had the greatest mass (1.42 g), but the lowest oil content (5.37% w/w); the control seeds showed smaller mass (1.21 g), but higher oil content (13.57% w/w). The proportion of fatty acids varied significantly among the treatments with respect to the control. The most abundant fatty acids were oleic (C18:1), lauric (C12:0), myristic (C14:0), palmitic (C16:0), linoleic (C18:2), and stearic (C18:0). Together these fatty acids presented a composition between 98.3 and 98.67% for treatments, and 99.0% for the control. The results indicate that the pollen sources from Deglet Noor, Khadrawy, Medjool and Zahidi cultivars had a significant effect on mass, dimension, oil content and fatty acid profile of the seeds of the date cultivar Medjool. The date seed oil could be used as edible oil, in food products, and in pharmaceutical and cosmetic applications. | La presente investigación tuvo como objetivo evaluar el efecto de las fuentes de polen, sobre la masa, dimensión, contenido de aceite y el perfil de ácidos grasos de las semillas de dátil del cultivar Medjool. Las palmas hembras del cultivar Medjool fueron polinizadas con cultivares Deglet Noor, Khadrawy, Medjool y Zahidi. Además, tres palmas fueron polinizadas como tratamiento control. Los ácidos grasos se evaluaron por cromatografía de gases-espectrometría de masas. La morfología de la superficie del polvo de semillas de dátil se examinó utilizando un equipo SEM, antes y después de la interacción n-hexano. Las semillas del tratamiento Medjool resultaron con mayor masa (1,42 g), pero menor contenido de aceite (5,37% p/p); la semilla control, mostró una masa más pequeña (1,21 g), pero un mayor contenido de aceite (13,57% p/p). La composición de ácidos grasos varió significativamente entre los tratamientos con respecto al control. Los ácidos grasos mayoritarios fueron: oleico (C18:1), láurico (C12:0), mirístico (C14:0), palmítico (C16:0), linoleico (C18:2) and esteárico (C18:0). En total, estos ácidos grasos alcanzan una composición entre 98.3 y 98.67% para los tratamientos, y 99.0% para el control. Los resultados indican que la fuente de polen de los cultivares Deglet Noor, Khadrawy, Medjool y Zahidi tiene un efecto significativo sobre la masa, dimensión, contenido de aceite y el perfil de ácidos grasos de la semilla del cultivar de dátil Medjool. El aceite de la semilla de dátil, podría usarse como aceite comestible, productos alimenticios, aplicaciones farmacéuticas y cosméticas.
显示更多 [+] 显示较少 [-]Epifaunal and infaunal responses to submarine mine tailings in a Norwegian fjord 全文
2019
Trannum, Hilde C | Borgersen, Gunhild | Oug, Eivind | Glette, Tormod | Brooks, Lucy | Ramirez-Llodra, Eva
Disposal of mine tailings in marine shallow water ecosystems represents an environmental challenge, and the present paper reports results from a field study in Frænfjorden, Norway, which is subject to such disposal. Structural and functional responses of benthic infauna and epifauna were investigated along a gradient from heavy tailings deposition to reference conditions. The tailings clearly impacted the faunal composition, with lowered species number close to the outfall. Total abundance of infauna increased in the most impacted area due to dominance of opportunistic species, whereas the epifauna was reduced and represented by a few scattered specimens only. In the most impacted area functional responses included an increase in mobile carnivores/omnivores and species utilizing symbionts. Sessile and tube-living taxa, and deposit and suspension feeders decreased, probably due to smothering in combination with tailings-associated changes of the substrate. Functional diversity decreased for both infauna and epifauna, but less than the structural diversity. | publishedVersion
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