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Spatial trends of chlorinated paraffins and dechloranes in air and soil in a tropical urban, suburban, and rural environment Полный текст
2022
Nipen, Maja | Vogt, Rolf David | Bohlin-Nizzetto, Pernilla | Borgå, Katrine | Mwakalapa, Eliezer Brown | Borgen, anders Røsrud | Jørgensen, Susanne Jøntvedt | Ntapanta, Samwel Moses | Mmochi, Aviti John | Schlabach, Martin | Breivik, Knut
There are large knowledge gaps concerning environmental levels and fate of many organic pollutants, particularly for chemicals of emerging concern in tropical regions of the Global South. In this study, we investigated the levels of chlorinated paraffins (CPs) and dechloranes in air and soil in rural, suburban, and urban regions in and around Dar es Salaam, Tanzania. Samples were also collected near the city's main municipal waste dumpsite and an electronic waste (e-waste) handling facility. In passive air samples, short chain CPs (SCCPs) dominated, with an average estimated concentration of 22 ng/m3, while medium chain CPs (MCCPs) had an average estimated concentration of 9 ng/m3. The average estimated air concentration of ∑dechloranes (Dechlorane Plus (DP) + Dechlorane 602 + Dechlorane 603) was three to four orders of magnitudes lower, 2 pg/m3. In soil samples, MCCPs dominated with an average concentration of 640 ng/g dw, followed by SCCPs with an average concentration of 330 ng/g dw, and ∑dechloranes with an average concentration of 0.9 ng/g dw. In both air and soil, DP was the dominating dechlorane compound. Urban pulses were observed for CPs and dechloranes in air and soil. CPs were in addition found in elevated levels at the municipal waste dumpsite and the e-waste handling facility, while DPs were found in elevated levels at the e-waste handling facility. This suggests that waste handling sites represent important emission sources for these pollutants. Investigations into seasonal trends and environmental fate of CPs and dechloranes showed that monsoonal rain patterns play a major role in governing air concentrations and mobility, particularly for the less volatile MCCPs and dechloranes. This study is the first to report levels of CPs in air from sub-Saharan Africa, and DP, Dechlorane 602, and Dechlorane 603 in soil from sub-Saharan Africa. | publishedVersion
Показать больше [+] Меньше [-]Catches in abandoned snow crab (Chionoecetes opilio) pots in the Barents Sea Полный текст
2021
Humborstad, Odd Børre | Eliassen, Lasse Krøger | Siikavuopio, Sten Ivar | Løkkeborg, Svein | Ingolfsson, Olafur Arnar | Hjelset, Ann Merete
During a 2018 retrieval cruise for abandoned snow crab (Chionoecetes opilio) pots in the Barents Sea, approximately 8600 pots abandoned 1.5 years earlier were recovered. Forty-three percent of a subsample of 1000 pots contained snow crabs, with an average of three crabs per pot. Most of the crabs were alive (~98%) and dominated by large males. Pinch injuries and limb loss were common and tended to decline with increasing crab size. Reflex testing showed that the crabs were vital (i.e. the crabs moved their legs, chelipeds and maxillipeds when stimulated), which was supported by a relatively high meat content. However, energy reserves in the digestive glands (hepatopancreas reserves) were low, indicating overall energy deficiencies. Our results indicate considerable unaccounted mortality due to self-baiting, continued catch and cannibalism. The findings demonstrate that snow crab pots which are lost or abandoned in the Barents Sea fishery maintain huge potential for ghost-fishing impacts. | publishedVersion
Показать больше [+] Меньше [-]Catches in abandoned snow crab (Chionoecetes opilio) pots in the Barents Sea Полный текст
2021
Humborstad, Odd Børre | Eliassen, Lasse Krøger | Siikavuopio, Sten Ivar | Løkkeborg, Svein | Ingolfsson, Olafur Arnar | Hjelset, Ann Merete
publishedVersion
Показать больше [+] Меньше [-]Gaps in current Baltic Sea environmental monitoring – Science versus management perspectives Полный текст
2020
Kahlert, Maria | Eilola, Kari | Mack, Leoni | Meissner, Kristian | Sandin, Leonard | Strömberg, Helena | Uusitalo, Laura | Viktorsson, Lena | Liess, Antonia
Legislations and commitments regulate Baltic Sea status assessments and monitoring. These assessments suffer from monitoring gaps that need prioritization. We used three sources of information; scientific articles, project reports and a stakeholder survey to identify gaps in relation to requirements set by the HELCOM's Baltic Sea Action Plan, the Marine Strategy Framework Directive and the Water Framework Directive. The most frequently mentioned gap was that key requirements are not sufficiently monitored in space and time. Biodiversity monitoring was the category containing most gaps. However, whereas more than half of the gaps in reports related to biodiversity, scientific articles pointed out many gaps in the monitoring of pollution and water quality. An important finding was that the three sources differed notably with respect to which gaps were mentioned most often. Thus, conclusions about gap prioritization for management should be drawn after carefully considering the different viewpoints of scientists and stakeholders. | publishedVersion
Показать больше [+] Меньше [-]Biodegradation of weathered crude oil in seawater with frazil ice Полный текст
2020
Lofthus, Synnøve | Bakke, Ingrid | Tremblay, Julien | Greer, Charles | Brakstad, Odd Gunnar
As ice extent in the Arctic is declining, oil and gas activities will increase, with higher risk of oil spills to the marine environment. To determine biotransformation of dispersed weathered oil in newly formed ice, oil dispersions (2–3 ppm) were incubated in a mixture of natural seawater and frazil ice for 125 days at −2 °C. Dispersed oil in seawater without frazil ice were included in the experimental setup. Presence or absence of frazil ice was a strong driver for microbial community structures and affected the rate of oil degradation. n-alkanes were degraded faster in the presence of frazil ice, the opposite was the case for naphthalenes and 2–3 ring PAHs. No degradation of 4–6 ring PAHs was observed in any of the treatments. The total petroleum oil was not degraded to any significant degree, suggesting that oil will freeze into the ice matrix and persist throughout the icy season. | publishedVersion
Показать больше [+] Меньше [-]Microplastic dispersal behavior in a novel overhead stirring aqueous exposure system Полный текст
2020
Salaberria, Iurgi | Nadvornik-Vincent, Colette | Monticelli, Giovanna | Altin, Dag | Booth, Andy
Using nominal dose metrics to describe exposure conditions in laboratory-based microplastic uptake and effects studies may not adequately represent the true exposure to the organisms in the test system, making data interpretation challenging. In the current study, a novel overhead stirring method using flocculators was assessed for maintaining polystyrene (PS) microbeads (Ø10.4 μm; 1.05 g cm−3) in suspension in seawater during 24 h and then compared with static and rotational exposure setups. Under optimized conditions, the system was able to maintain 59% of the initial PS microbeads in suspension after 24 h, compared to 6% using a static system and 100% using a rotating plankton wheel. Our findings document for the first time that overhead stirring as well as other, commonly used exposure systems (static) are unable to maintain constant microplastic exposure conditions in laboratory setups whereas rotation is very effective. This suggests toxicological studies employing either static or overhead stirring systems may be greatly overestimating the true microplastic exposure conditions. | publishedVersion
Показать больше [+] Меньше [-]Relationships between Pb, As, Cr, and Cd in individual cows’ milk and milk composition and heavy metal contents in water, silage, and soil Полный текст
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)
Показать больше [+] Меньше [-]Maternal transfer of organohalogenated compounds in sharks and stingrays Полный текст
2015
Weijs, Liesbeth | Briels, Nathalie | Adams, Douglas | Lepoint, Gilles | Das, Krishna | Blust, Ronny | Covaci, Adrian
peer reviewed | Elasmobranchs can bioaccumulate considerable amounts of persistent organic pollutants (POPs) and utilize several reproductive strategies thereby influencing maternal transfer of contaminants. This study provides preliminary data on the POP transfer from pregnant females to offspring of three species (Atlantic stingrays, bonnethead, blacktip sharks) with different reproduction modes (aplacental, placental viviparity). Polychlorinated biphenyl (PCB) levels were generally higher than any other POPs. Stingrays and blacktip shark embryos contained the lowest POP concentrations while bonnetheads and the blacktip adult female had the highest concentrations. Results suggest that are more readily transferred from the mother to the embryo compared to what is transferred to ova in stingrays. Statistically significant differences in levels of selected POPs were found between embryos from the left and right uterus within the same litter as well as between female and male embryos within the same litter for bonnetheads, but not for the blacktip sharks.
Показать больше [+] Меньше [-]Biosorption Capacity for Cadmium of Brown Seaweed Sargassum sinicola and Sargassum lapazeanum in the Gulf of California Полный текст
2011
MONICA PATRON PRADO | MARIA MARGARITA CASAS VALDEZ | Elisa Serviere Zaragoza | TANIA ZENTENO SAVIN | Daniel Bernardo Lluch Cota | Lía Celina Méndez Rodríguez
"Brown algae Sargassum sinicola and Sargassum lapazeanum were tested as cadmium biosorbents in coastal environments close to natural and enriched areas of phosphorite ore. Differences in the concentration of cadmium in these brown algae were found, reflecting the bioavailability of the metal ion in seawater at several sites. In the laboratory, maximum biosorption capacity (q max) of cadmium by these nonliving algae was determined according to the Langmuir adsorption isotherm as 62.42 ± 0.44 mg g−1 with the affinity constant (b) of 0.09 and 71.20 ± 0.80 with b of 0.03 for S. sinicola and S. lapazeanum, respectively. Alginate yield was 19.16 ± 1.52% and 12.7 ± 1.31%, respectively. Although S. sinicola had far lower biosorption capacity than S. lapazeanum, the affinity for cadmium for S. sinicola makes this alga more suitable as a biosorbent because of its high q max and large biomass on the eastern coast of the Baja California Peninsula. Sargassum biomass was estimated at 180,000 t, with S. sinicola contributing to over 70%."
Показать больше [+] Меньше [-]Cytochrome P450 1A1 expression in cetacean skin biopsies from the Indian Ocean Полный текст
2011
Jauniaux, Thierry | Farnir, Frédéric | Fontaine, Michael | Kiszka, Jeremy | Sarlet, Michaël | Coignoul, Freddy
peer reviewed
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