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Determinants of airborne benzene evaporating from fresh crude oils released into seawater Полный текст
2019
Gjesteland, Ingrid | Hollund, Bjørg Eli | Kirkeleit, Jorunn | Daling, Per S. | Sørheim, Kristin Rist | Bråtveit, Magne
Determinants of airborne benzene evaporating from fresh crude oils released into seawater Полный текст
2019
Gjesteland, Ingrid | Hollund, Bjørg Eli | Kirkeleit, Jorunn | Daling, Per S. | Sørheim, Kristin Rist | Bråtveit, Magne
Benzene, toluene, ethylbenzene, xylenes, naphthalene and n-hexane evaporating from a thin oil film was measured for 30 min in a small-scale test system at 2 and 13 °C and the impact of physicochemical properties on airborne benzene with time after bulk oil release was studied. Linear mixed-effects models for airborne benzene in three time periods; first 5, first 15 and last 15 min of sampling, indicated that benzene content in fresh oil, oil group (condensate/light crude oil) and pour point were significant determinants explaining 63–73% of the total variance in the outcome variables. Oils with a high pour point evaporated considerably slower than oils with a low pour point. The mean air concentration of total volatile organic compounds was significatly higher at 13 °C (735 ppm) compared to 2 °C (386 ppm) immediately after release of oil, but at both temperatures the concentration rapidly declined.
Показать больше [+] Меньше [-]Determinants of airborne benzene evaporating from fresh crude oils released into seawater Полный текст
2019
Gjesteland, Ingrid | Hollund, Bjørg Eli | Kirkeleit, Jorunn | Daling, Per Snorre | Sørheim, Kristin Rist
Benzene, toluene, ethylbenzene, xylenes, naphthalene and n-hexane evaporating from a thin oil film was measured for 30 min in a small-scale test system at 2 and 13 °C and the impact of physicochemical properties on airborne benzene with time after bulk oil release was studied. Linear mixed-effects models for airborne benzene in three time periods; first 5, first 15 and last 15 min of sampling, indicated that benzene content in fresh oil, oil group (condensate/light crude oil) and pour point were significant determinants explaining 63–73% of the total variance in the outcome variables. Oils with a high pour point evaporated considerably slower than oils with a low pour point. The mean air concentration of total volatile organic compounds was significatly higher at 13 °C (735 ppm) compared to 2 °C (386 ppm) immediately after release of oil, but at both temperatures the concentration rapidly declined. | acceptedVersion
Показать больше [+] Меньше [-]Organochlorine pesticides in commercial Pacific salmon in the Russian Far Eastern seas: Food safety and human health risk assessment Полный текст
2019
Tsygankov, V.Yu | Lukyanova, O.N. | Boyarova, M.D. | Gumovskiy, A.N. | Donets, M.M. | Lyakh, V.A. | Korchagin, V.P. | Prikhodko, Yu.V.
Concentration of organochlorine pesticides (OCPs) (α-, β-, γ- hexachlorocyclohexane (HCH), dichlorodiphenyltrichloroethane (DDT), dichlorodiphenyldichloroethane (DDD), dichlorodiphenyldichloroethylene (DDE)) in four species of Pacific salmon (pink, chum, chinook, and sockeye) are presented. OCPs in salmon organs increased in the following order: muscle < liver < eggs < male gonads. Concentrations of the OCP in salmon organs increased in following order: DDE < γ-HCH < α-HCH. The level of pollutants in salmon is compared with the sanitary and epidemiological norms of Russia and other countries. Cancer and noncancer hazard ratios through consumption of salmon in Russian Far East for both men and women also were summarized. Noncancer and cancer hazard ratio values were far below threshold values (<1.0).
Показать больше [+] Меньше [-]Natural radioactivity and radiation hazard assessment of industrial wastes from the coastal phosphate treatment plants of Gabes (Tunisia, Southern Mediterranean Sea) Полный текст
2019
El Zrelli, Radhouan | Rabaoui, Lotfi | van Beek, Pieter | Castet, Sylvie | Souhaut, Marc | Grégoire, Michel | Courjault-Radé, Pierre
This work is a first contribution to the knowledge of natural radionuclides (²²⁶Ra, ²³⁸U, ⁴⁰K, and ²³²Th) activities in phosphate rock (NORM), phosphogypsum, and phosphogypsum foam (TENORM) from the coastal fertilizer plants of Gabes (Southeastern Tunisia) and the assessment of their radiation hazards on human health and the surrounding environment. In the three studied materials, activities were found to be in the range of 35.4 (⁴⁰K)–375.1 (²²⁶Ra), 10.0 (⁴⁰K)–220.2 (²²⁶Ra), and 79.2 (²³²Th)–1168.6 Bq kg⁻¹ (²²⁶Ra), respectively. Considering the studied radionuclides and materials, the corresponding decreasing activity orders were found to be ²²⁶Ra > ²³⁸U > ⁴⁰K > ²³²Th and PGF > PR > PG, respectively. All human health hazard indices exceeded the worldwide recommended safety limits, which show that the workers in Gabes phosphate fertilizer plants as well as the neighboring human community may potentially be exposed to significant radiation, which may cause several diseases and malformations. It is therefore recommended to avoid and/or reduce the potential fertilizer industry radioactive impact in the area.
Показать больше [+] Меньше [-]Distribution and accumulation of artificial radionuclides in marine products around Korean Peninsula Полный текст
2019
Kim, Suk Hyun | Lee, Hyunmi | Yi, Sang-han | Kim, Intae
We investigated the distributions of the artificial radionuclides ¹³⁷Cs, ²³⁹⁺²⁴⁰Pu, and ⁹⁰Sr in the various marine products around Korean Peninsula collected in 2015–2017. The activities of ¹³⁷Cs, ²³⁹⁺²⁴⁰Pu, and ⁹⁰Sr were in the ranges of 12.2–258.4 mBq kg⁻¹, 0.014–1.879 mBq kg⁻¹, and 11.3–18.3 mBq kg⁻¹, respectively. The higher ²³⁹⁺²⁴⁰Pu (a factor of 10–50) relative to fishes were observed in mollusks. ¹³⁷Cs in fishes were significantly enriched with growths. The calculated concentration factors (CFs) of ¹³⁷Cs, ²³⁹⁺²⁴⁰Pu, and ⁹⁰Sr in marine products were 7–143, 3–407, and 15–25, respectively. Overall, no noticeable artificial radioactivity was detected in marine organisms when comparing these results with previous data reported before the Fukushima nuclear accident and recommended CF values. The annual effective doses of ¹³⁷Cs, ²³⁹⁺²⁴⁰Pu, and ⁹⁰Sr by seafood consumption in South Korea were estimated to be 1.1 × 10⁻⁴, 1.6 × 10⁻⁵ and, 2.9 × 10⁻⁵ mSv yr⁻¹, respectively, which is insignificant relative to that of natural radionuclides.
Показать больше [+] Меньше [-]Spatial and temporal trends of PCDD/Fs in sediment and bivalves along the Korean coasts during 2001–2012 Полный текст
2019
Kim, Eun-Kyo | Barghi, Mandana | Choi, Minkyu | Moon, Hyo-Bang
Concentrations of polychlorinated dibenzo-para-dioxins and dibenzofurans (PCDD/Fs) were measured in sediment and bivalves at 25 locations along the Korean coasts during 2001–2012. Concentrations of PCDD/Fs in sediment and bivalves ranged from 0.15 to 18.9 pg TEQ/g dry weight and from 0.06 to 7.70 pg TEQ/g wet weight, respectively. Elevated PCDD/F concentrations were found at locations close to largest industrial complexes and commercial harbors. A significant decreasing trend of PCDD/Fs in sediment was associated with strong regulation of PCDD/Fs, whereas levels in bivalves did not show a decreasing trend. Octachlorinated dibenzo-p-dioxin (OCDD) was predominant in sediment, while tetrachlorinated dibenzofuran and OCDD were predominant in bivalves. Almost half (46%) of sediment samples exceeded the threshold effect level suggested by the US National Oceanic and Atmospheric Administration, implying ecotoxicological risks to benthic organisms. Our findings support the effectiveness of legislative action on PCDD/Fs for coastal environments of Korea.
Показать больше [+] Меньше [-]Microplastics in the surface seawaters of Chabahar Bay, Gulf of Oman (Makran Coasts) Полный текст
2019
Aliabad, Mojgan Khamarzadeh | Nassiri, Mahmoud | Kor, Kamalodin
Current study aimed to evaluate the microplastics abundance in the surface waters of Chabahar Bay for the first time. 21 neuston net water samples were collected from 7 stations. Microplastics were visually counted by stereomicroscope, sorted into 4 size categories, 4 shape categories, and identified by ATR-FTIR spectroscopy. Density of microplastics varied from 0.07 ± 0.03 to 1.14 ± 0.27 with an average density of 0.49 ± 0.43 particle·m−3. Microplastics were mostly found in the shape of fibers. 69% of analyzed particles were polyethylene and polypropylene. Main colors of the collected microplastics were white, blue and red. The results showed that the largest number of microplastics was found at station near populated area. Therefore, it can be concluded that, there is a pressing-need to investigate the distribution of microplastics in sediments and biota of this Bay as well as their effects on marine life and human health.
Показать больше [+] Меньше [-]Low incidence of plastic ingestion among three fish species significant for human consumption on the island of Newfoundland, Canada Полный текст
2019
Liboiron, Max | Melvin, Jess | Richárd, Natalie | Saturno, Jacquelyn | Ammendolia, Justine | Liboiron, France | Charron, Louis | Mather, Charles
This study reports the first baselines of plastic ingestion for three fish species that are common commercial and sustenance food fish in Newfoundland. Species collections occurred between 2015 and 2016 for Atlantic cod (Gadus morhua), Atlantic salmon (Salmo salar), and capelin (Mallotus villosus). The frequency of occurrence (%FO) of plastic ingestion for both Atlantic salmon (n = 69) and capelin (n = 350) was 0%. Of the 1010 Atlantic cod individuals collected over two years, 17 individuals had ingested plastics, a %FO of 1.68%. This is the only multi-year investigation of plastic ingestion in Atlantic cod for the Northwest Atlantic, and the first baseline of plastic ingestion in Atlantic salmon and capelin on the island of Newfoundland. Considering the ecological, economic, and cultural importance of these fish species, this study is the beginning of a longitudinal study of plastic ingestion to detect any future changes in contamination levels.
Показать больше [+] Меньше [-]Marine contamination and cytogenotoxic effects of fluoxetine in the tropical brown mussel Perna perna Полный текст
2019
Cortez, Fernando Sanzi | Souza, Lorena da Silva | Guimarães, Luciana Lopes | Pusceddu, Fabio Hermes | Maranho, Luciane Alves | Fontes, Mayana Karoline | Moreno, Beatriz Barbosa | Nobre, Caio Rodrigues | Abessa, Denis Moledo de Souza | Cesar, Augusto | Pereira, Camilo Dias Seabra
Concerns are growing about the presence of fluoxetine (FLX) in environmental matrices, as well as its harmful effects on non-target organisms. FLX in aquatic ecosystems has been detected in a range varying from pg/L to ng/L, while adverse effects have been reported in several organisms inhabiting freshwater and marine environments. The present study quantifies FLX concentrations in seawater samples from Santos Bay, Brazil and assesses metabolic responses and sublethal effects on the tropical brown mussel Perna perna. Levels of ethoxyresorufin‑O‑deethylase, dibenzylfluorescein dealkylase, glutathione S-transferase, glutathione peroxidase, cholinesterase, lipoperoxidation, and DNA damage were assessed in the gills and digestive gland of these animals, and lysosomal membrane stability was also assessed in hemocytes. FLX altered phase I and II enzyme activities, caused cytogenotoxic effects, and negatively impacted the overall health of mussels exposed to environmentally relevant concentrations. These findings contribute to characterize the risks of introducing this drug into the marine environment.
Показать больше [+] Меньше [-]Differential impact of anthropogenic pressures on Caspian Sea ecoregions Полный текст
2019
Lattuada, Matteo | Albrecht, Christian | Wilke, Thomas
Differential impact of anthropogenic pressures on Caspian Sea ecoregions Полный текст
2019
Lattuada, Matteo | Albrecht, Christian | Wilke, Thomas
Over the past decades, overall ecological conditions in the Caspian Sea have deteriorated. However, a comprehensive understanding of lake-wide spatial differences in anthropogenic pressures is lacking and the biological consequences of human impacts are poorly understood. This paper therefore aims at assessing the individual and combined effects of critical anthropogenic pressures on the Caspian Sea ecoregions. First, cumulative pressure scores were calculated with a cumulative environmental assessment (CEA) analysis. Then, the individual contribution of anthropogenic pressures was quantified. Finally, ecoregion-specific differences were assessed. The analyses show that both cumulative and individual pressure scores are unevenly distributed across the Caspian Sea. The most important individual pressures are invasive species, chemical pollution and poaching. This uneven distribution of pressure scores across Caspian Sea ecoregions creates new challenges for future conservation strategies, as different ecoregions usually require different conservation measures.
Показать больше [+] Меньше [-]Differential impact of anthropogenic pressures on Caspian Sea ecoregions Полный текст
2019
Lattuada, Matteo | Albrecht, Christian | Wilke, Thomas
Over the past decades, overall ecological conditions in the Caspian Sea have deteriorated. However, a comprehensive understanding of lake-wide spatial differences in anthropogenic pressures is lacking and the biological consequences of human impacts are poorly understood. This paper therefore aims at assessing the individual and combined effects of critical anthropogenic pressures on the Caspian Sea ecoregions. First, cumulative pressure scores were calculated with a cumulative environmental assessment (CEA) analysis. Then, the individual contribution of anthropogenic pressures was quantified. Finally, ecoregion-specific differences were assessed. The analyses show that both cumulative and individual pressure scores are unevenly distributed across the Caspian Sea. The most important individual pressures are invasive species, chemical pollution and poaching. This uneven distribution of pressure scores across Caspian Sea ecoregions creates new challenges for future conservation strategies, as different ecoregions usually require different conservation measures.
Показать больше [+] Меньше [-]Climate Change Penalty to Ozone Air Quality: Review of Current Understandings and Knowledge Gaps Полный текст
2019
Fu, Tzung-May | Tian, Heng
PURPOSE OF REVIEW: Climate warming may bear a penalty on future ozone air quality, even in the absence of changes in anthropogenic activities. This penalty has important implications for policy-making, but its quantification involves complex meteorological, chemical, and biological processes and feedbacks that are not well understood. We examined how climate-sensitive processes may affect surface ozone, identified key knowledge gaps uncovered by recent studies, and summarized latest assessments of the climate change penalty on ozone air quality. RECENT FINDINGS: Recent analyses have challenged earlier paradigms on how climate change may affect surface ozone. The widely accepted associations of high ozone events with stagnation and heat waves require re-examination. Emission responses of natural precursors to climate warming may be significantly modulated by CO₂ levels and ecosystem feedbacks, such that the direction of emission changes cannot be robustly determined at this time. Climate variability may drive fluctuations in surface ozone, which has implications for near-term air quality management. Recent studies have generally projected a climate change penalty on ozone air quality, although the magnitudes are smaller than those projected by earlier studies. This review examined the latest understanding on the climate change penalty to surface ozone. Critical uncertainties are associated with the meteorological, chemical, and biological processes linking climate warming and ozone, and many of the known feedbacks are not yet included in models. Further research is needed to examine those processes in order to better quantify the climate change penalty on surface ozone to inform policy-making.
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