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Physiological effects of toxic elements on a wild nightjar species Полный текст
2020
Espín, Silvia | Sánchez-Virosta, Pablo | Zamora-Marín, José M. | León-Ortega, Mario | Jiménez, Pedro | Zamora-López, Antonio | Camarero, Pablo R. | Mateo, Rafael | Eeva, Tapio | García-Fernández, Antonio J.
Nightjars are considered human-tolerant species due to the population densities reached in strongly managed landscapes. However, no studies have been done evaluating metal-related effects on physiology, condition or fitness in any nightjar species. The main aim of this study was to evaluate how metal exposure affects physiology and condition in red-necked nightjar (Caprimulgus ruficollis) populations inhabiting three different environments in southeastern Spain: agricultural-urban area (n = 15 individuals), mining area (n = 17) and control area (n = 16).Increased plasma mineral levels (magnesium and calcium) and alkaline phosphatase (ALP) activity were observed in breeding females, and ALP was significantly higher in young birds due to bone growth and development. In the mining-impacted environment, nightjars showed decreased retinol (17.3 and 23.6 μM in the mining area and control area), uric acid (28.8 and 48.6 mg/dl in the mining area and control area) and albumin (16.2 and 19.6 g/l in the mining area and control area), probably impaired by a combination of toxic metal exposure and low prey quantity/quality in that area. Moreover, they showed increased plasma tocopherol levels (53.4 and 38.6 μM in the mining area and control area) which may be a response to cope with metal-induced oxidative stress and lipid peroxidation. Blood concentrations of toxic metals (As, Pb, Cd and Hg) were negatively associated with calcium, phosphorus, magnesium, ALP, total proteins and body condition index. This could lead to metal-related disorders in mineral metabolism and ALP activity that may potentially increase the risk of skeletal pathologies and consequent risk of fractures in the long term, compromising the survival of individuals. Further studies need to be carried out to evaluate potential metal-related effects on the antioxidant status and bone mineralization of nightjars inhabiting mining environments.
Показать больше [+] Меньше [-]Effects of biological factors and seasonality on the level of polycyclic aromatic hydrocarbons in red mullet (Mullus barbatus) Полный текст
2020
Frapiccini, E. | Panfili, M. | Guicciardi, S. | Santojanni, A. | Marini, M. | Truzzi, C. | Annibaldi, A.
This study evaluates the effects of biological factors of fish and seasonality on Polycyclic Aromatic Hydrocarbon (PAH) accumulation in red mullet (Mullus barbatus) tissue. Specimens were collected monthly with a bottom trawl net in an offshore fishing ground in the Northern and Central Adriatic Sea (Geographical Sub Area 17) throughout 2016.The edible fillets of 380 individuals were analyzed for the concentrations of individual PAH, total PAH, and low, medium and high molecular weight (MW) PAHs. PAH bioaccumulation was related to their physicochemical characteristics (MW, and logarithm of the octanol-water partition coefficient, log Kₒw), some biological parameters of fish (body size, age, sex, reproductive stage and total lipid content), and catch season.The PAH bioaccumulation pattern and the effects of the different factors varied according to PAH MW. The heavier (medium and high MW) PAHs showed higher levels in winter-autumn and in pre-spawners compared with spawners and post-spawners. Our findings suggest that an important detoxification mechanism, albeit limited to the heavier PAHs, acts in the spawning and post-spawning stage. Low MW PAHs appeared to be unaffected by reproductive stage, lipid content and seasonality. Reproductive stage and seasonality seem to play an important role in the accumulation of heavier PAH, whereas total lipid content and age seem to exert a limited influence, and body size no effect at all.
Показать больше [+] Меньше [-]Application of equilibrium passive sampling to profile pore water and accessible concentrations of hydrophobic organic contaminants in Danube sediments Полный текст
2020
Belháčová-Minaříková, Michaela | Smedes, Foppe | Rusina, Tatsiana P. | Vrana, Branislav
Total concentrations of hydrophobic organic contaminants (HOCs) in sediment present a poor quality assessment parameter for aquatic organism exposure and environmental risk because they do not reflect contaminant bioavailability. The bioavailability issue of HOCs in sediments can be addressed by application of multi-ratio equilibrium passive sampling (EPS). In this study, riverbed sediment samples were collected during the Joint Danube Survey at 9 locations along the Danube River in 2013. Samples were ex-situ equilibrated with silicone passive samplers. Desorption isotherms were constructed, yielding two endpoints: pore water (CW:₀) and accessible (CAS:₀) concentration of polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), polycyclic aromatic hydrocarbons (PAHs) and polybrominated diphenyl ethers in sediment. CW:₀ concentrations of DDT and its breakdown products exhibited elevated levels in the low Danube, with the maximum in the river delta. Other investigated HOCs did not show any clear spatial trends along the river, and only a moderate CW:₀ variability. CAS:₀ in sediment ranged from 10 to 90% of the total concentration in sediment. CW:₀ was compared with freely dissolved concentration in the overlaying surface water, measured likewise by passive sampling. The comparison indicated potential compound release from sediment to the water phase for PAHs with less than four aromatic rings, and for remaining HOCs either equilibrium between sediment and water, or potential compound deposition in sediment. Sorption partition coefficients of HOC to organic carbon correlated well with octanol-water partition coefficients (KOW), showing stronger sorption of PAHs to sediment than that of PCBs and OCPs having equal logKOW. Comparison of CW:₀ values with European environmental quality standards indicated potential exceedance for hexachlorobenzene, fluoranthene and benzo[a]pyrene at several sites. The study demonstrates the utility of passive sampling as an innovative approach for risk-oriented monitoring of HOCs in river catchments.
Показать больше [+] Меньше [-]Heterogeneous reaction of ozone with syringic acid: Uptake of O3 and changes in the composition and optical property of syringic acid Полный текст
2020
Zhang, Tingting | Yang, Wangjin | Han, Chŏng | Yang, He | Xue, Xiangxin
Syringic acid, which is a typical methoxyphenol emitted from wood combustion, can provide heterogeneous reaction sites for gaseous active components, influencing the concentrations of trace gases and the compositions of syringic acid. The heterogeneous uptake of O₃ on syringic acid was investigated using a flow tube reactor under ambient pressure. The initial uptake coefficient (γᵢ) and the steady-state uptake coefficient (γₛₛ) of O₃ linearly increased with syringic acid mass (0–0.16 μg cm⁻²) and temperature (278–328 K), while they decreased with increasing the O₃ concentration and the O₂ content. The γᵢ was independent of relative humidity (20%–70%), whereas γₛₛ decreased with relative humidity (7%–70%). The compositional changes of syringic acid by the ozonization were analyzed by the Fourier transform infrared spectrometer (FT-IR) and the gas chromatography-mass spectrometry (GC-MS), confirming the generation of 2,6-dimethoxy-1,4-benzoquinone. In addition, compared to that of fresh syringic acid, the mass absorption efficiency of syringic acid aged by O₃ exhibited an increase in the range of 290–320 nm.
Показать больше [+] Меньше [-]Temporal dynamic of anthropogenic fibers in a tropical river-estuarine system Полный текст
2020
Strady, Emilie | Kieu-Le, Thuy-Chung | Gasperi, Johnny | Tassin, Bruno
Temporal dynamic of anthropogenic fibers in a tropical river-estuarine system Полный текст
2020
Strady, Emilie | Kieu-Le, Thuy-Chung | Gasperi, Johnny | Tassin, Bruno
Anthropogenic fibers, gathering synthetic fibers, artificial fibers and natural fibers are ubiquitous in the natural environment. Tremendous concentrations of anthropogenic fibers were previously measured in the tropical Saigon River (Vietnam), i.e. a river impacted by textile and apparel industries. In the present study, we want to examine the role of contrasted seasonal variation (e.g., dry and rainy seasons), via the rainfall and monthly water discharges, and of water's physico-chemical conditions on the concentrations of anthropogenic fibers in the surface water. The one year and half monthly survey evidenced that concentrations of anthropogenic fibers varied from 22 to 251 items L⁻¹ and their variations were not related to rainfall, water discharge or abiotic factors. However, their color and length distribution varied monthly suggesting variations in sources and sinks. Based on the 2017 survey, we estimated an annual emission of anthropogenic fibers from the river to the downstream coastal zone of 115–164 × 10¹² items yr⁻¹.
Показать больше [+] Меньше [-]Temporal dynamic of anthropogenic fibers in a tropical river-estuarine system Полный текст
2020
Strady, Emilie | Kieu-Le, Thuy-Chung | Gasperi, Johnny | Tassin, Bruno | Institut méditerranéen d'océanologie (MIO) ; Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS) | Centre Asiatique de Recherche sur l'Eau (CARE) ; Ho Chi Minh City University of Technology [Vietnam National University, HCM] (HCMUT) ; Vietnam National University, Ho Chi Minh City / Đại học Quốc gia TP. Hồ Chí Minh (VNU-HCM)-Vietnam National University, Ho Chi Minh City / Đại học Quốc gia TP. Hồ Chí Minh (VNU-HCM) | Institut des Géosciences de l’Environnement (IGE) ; Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (Fédération OSUG)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP) ; Université Grenoble Alpes (UGA) | Ho Chi Minh City University of Technology [Vietnam National University, HCM] (HCMUT) ; Vietnam National University, Ho Chi Minh City / Đại học Quốc gia TP. Hồ Chí Minh (VNU-HCM) | Laboratoire Eau Environnement et Systèmes Urbains (LEESU) ; AgroParisTech-École nationale des ponts et chaussées (ENPC)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12) | Eau et Environnement (GERS-LEE) ; Université Gustave Eiffel
International audience | Anthropogenic fibers, gathering synthetic fibers, artificial fibers and natural fibers are ubiquitous in the natural environment. Tremendous concentrations of anthropogenic fibers were previously measured in the tropical Saigon River (Vietnam), i.e. a river impacted by textile and apparel industries. In the present study, we want to examine the role of contrasted seasonal variation (e.g., dry and rainy seasons), via the rainfall and monthly water discharges, and of water's physico-chemical conditions on the concentrations of anthropogenic fibers in the surface water. The one year and half monthly survey evidenced that concentrations of anthropogenic fibers varied from 22 to 251 items L-1 and their variations were not related to rainfall, water discharge or abiotic factors. However, their color and length distribution varied monthly suggesting variations in sources and sinks. Based on the 2017 survey, we estimated an annual emission of anthropogenic fibers from the river to the downstream coastal zone of 115e164 × 10 12 items yr-1.
Показать больше [+] Меньше [-]On-road emission measurements of reactive nitrogen compounds from heavy-duty diesel trucks in China Полный текст
2020
He, Liqiang | Zhang, Shaojun | Hu, Jingnan | Li, Zhenhua | Zheng, Xuan | Cao, Yihuan | Xu, Guangyi | Yan, Min | Wu, Ye
Emissions of major reactive nitrogen compounds, including nitric oxide (NO), nitrogen dioxide (NO₂) and ammonia (NH₃), from heavy-duty diesel vehicles (HDDVs) place substantial pressure on air quality for many large cities in China. To control nitrogen oxide (NOX) emissions from HDDVs, selective catalytic reduction (SCR) systems have been widely used since the China IV standards. To investigate the impacts of aftertreatment technologies and driving conditions on real-world emissions of reactive nitrogen compounds, a portable emissions measurement system was employed to test eighteen heavy-duty diesel trucks in China. The results showed that the China IV and China V HDDVs with appropriate SCR functionality could reduce NOX emissions by 36% and 53%, respectively, compared to the China III results, although their real-world emissions were still higher than the corresponding emission limits for regulatory engine tests. For these HDDVs, five samples were tested with NH₃ emissions, ranging from 1.67 ppm to 51.49 ppm. The NH₃ emission rates tended to significantly increase under high-speed driving conditions. The results indicate that the current SCR technology may have certain risks in exceeding the future China VI NH₃ limit. However, five China IV/V HDDVs were found to have SCR temperature sensors that were intentionally tampered with, resulting in comparable or even higher NOX emissions and zero NH₃ emissions. Increased NO₂ emissions due to the adoption of diesel oxidation catalysts and diesel particulate filters were also found from our experiments. This study highlights the importance of enhancing in-use compliance requirements and eliminating aftertreatment tampering for China IV and China V HDDVs.
Показать больше [+] Меньше [-]Mechanisms underlying silicon-dependent metal tolerance in the marine diatom Phaeodactylum tricornutum Полный текст
2020
Zhou, Beibei | Ma, Jie | Chen, Fengyuan | Zou, Yue | Wei, Yang | Zhong, Huan | Pan, Ke
Anthropogenic activities have significantly changed the stoichiometry and concentrations of nutrients in coastal waters. Silicon (Si) has become a potential limiting nutrient due to disproportionate nitrogen, phosphorus, and silicate inputs into these areas. The disrupted nutrient ratios can cause changes to metal sensitivity and accumulation in marine diatoms, an important group of eukaryotic phytoplankton that requires silicon for growth. In this study, we examined the effects of Si availability on the metal sensitivity in the diatom P. tricornutum. We found that Si starvation dramatically compromised its cadmium, copper, and lead tolerances. Interestingly, multiple lines of evidence indicated that Si-enriched cells had higher metal adsorption and influx rates than Si-starved cells. Yet Si-enriched cells also had a greater ability to respond to and counteract metal toxicity via elevated expression of membrane and vacuolar metal transporters and greater antioxidant activities which scavenge reactive oxygen species created by metal stress.
Показать больше [+] Меньше [-]Do whitefish (Coregonus lavaretus) larvae show adaptive variation in the avoidance of microplastic ingestion? Полный текст
2020
Huuskonen, Hannu | Subiron i Folguera, Joan | Kortet, Raine | Akkanen, Jarkko | Vainikka, Anssi | Janhunen, Matti | Kekäläinen, Jukka
Do whitefish (Coregonus lavaretus) larvae show adaptive variation in the avoidance of microplastic ingestion? Полный текст
2020
Huuskonen, Hannu | Subiron i Folguera, Joan | Kortet, Raine | Akkanen, Jarkko | Vainikka, Anssi | Janhunen, Matti | Kekäläinen, Jukka
The presence of microplastics in aquatic ecosystems has recently received increased attention. Small plastic particles may resemble natural food items of larval fish and other aquatic organisms, and create strong selective pressures on the feeding traits in exposed populations. Here, we examined if larval ingestion of 90 μm polystyrene microspheres, in the presence of zooplankton (Artemia nauplii, mean length = 433 μm), shows adaptive variation in the European whitefish (Coregonus lavaretus). A full-factorial experimental breeding design allowed us to estimate the relative contributions of male (sire) and female (dam) parents and full-sib family variance in early feeding traits, and also genetic (co)variation between these traits. We also monitored the magnitude of intake and elimination of microplastics from the alimentary tracts of the larvae. In general, larval whitefish ingested small numbers of microplastics (mean = 1.8, range = 0–26 particles per larva), but ingestion was marginally affected by the dam, and more strongly by the full-sib family variation. Microsphere ingestion showed no statistically significant additive genetic variation, and thus, no heritability. Moreover, microsphere ingestion rate covaried positively with the ingestion of Artemia, further suggesting that larvae cannot adaptively avoid microsphere ingestion. Together with the detected strong genetic correlation between food intake and microplastic intake, the results suggest that larval fish do not readily possess additive genetic variation that would help them to adapt to the increasing pollution by microplastics. The conflict between feeding on natural food and avoiding microplastics deserves further attention.
Показать больше [+] Меньше [-]Do whitefish (Coregonus lavaretus) larvae show adaptive variation in the avoidance of microplastic ingestion? Полный текст
2020
Huuskonen, Hannu | Subiron i Folguera, Joan | Kortet, Raine | Akkanen, Jarkko | Vainikka, Anssi | Janhunen, Matti | Kekäläinen, Jukka | https://orcid.org/0000-0002-5651-5287 | 4100110910 | Luonnonvarakeskus
Persistent ozone pollution episodes in North China exacerbated by regional transport Полный текст
2020
Gong, Cheng | Liao, Hong | Zhang, Lin | Yue, Xu | Dang, Ruijun | Yang, Yang
Summertime ozone (O₃) concentrations over China continue to increase although the governmental Clear Air Actions have been carried out since 2013. The worst O₃ pollution is confronted over North China Plain. Ozone polluted days (with observed regionally-averaged maximum daily 8-h average (MDA8) O₃ concentrations exceeding 80 ppbv) in May–July in North China increased from 35 days in year 2014 to 56 days in year 2018, and persistent O₃ pollution episodes that lasted for 5 days or longer (OPEs5) contributed 14.3% and 66.1% to those O₃ polluted days in 2014 and 2018, respectively. Model simulations suggest that O₃ transport from central eastern China (including Shandong, Henan, Jiangsu and Anhui Provinces) contributes 36% of the enhanced O₃ concentrations in North China during OPEs5 relative to the seasonal mean. We find that emission control of volatile organic compounds in central eastern China is most effective to alleviate intensity of OPEs5 in North China.
Показать больше [+] Меньше [-]Hydroponic growth test of maize sprouts to evaluate As, Cd, Cr and Pb translocation from mineral fertilizer and As and Cr speciation Полный текст
2020
Fioroto, Alexandre M. | Albuquerque, Luiza G.R. | Carvalho, Alexandrina A.C. | Oliveira, Aline P. | Rodrigues, Fábio | Oliveira, Pedro V.
The present study proposes a maize sprouts hydroponic growth model to evaluate the As, Cd, Cr and Pb translocation from multinutrient fertilizer and to do speciation of As and Cr in this fertilizer and As in parts of plant in order to predict their phytoavailability. X-ray absorption near edge structure (XANES) was employed to speciate As and Cr directly on fertilizer solid sample. Arsenate (Asⱽ) and a solid solution of FeCrO₃ were the major species identified in the samples. The sprouts were hydroponically cultivated in water, fertilizer slurry and fertilizer extract media. Concentrations of As, Cd and Pb measured on leaves of maize sprouts ranged from 0.061 to 0.31 mg kg⁻¹, whereas Cr was not translocated to the aerial parts of sprouts. High performance liquid chromatographic with inductively coupled plasma mass spectrometry (HPLC-ICP-MS) analysis was used to determine As speciation in maize sprouts, as well as in the fertilizer extracts and slurries. Arsenate was the only species identified in the initial fertilizer extract and this information is in agreement with the XANES results. However, the reduction of arsenate to arsenite was observed in extracts and slurries collected after sprout growth, probably due to the action of exudates secreted by plant roots. Arsenite was the predominant species identified in sprouts, the high phosphate concentration in the medium may have contributed to reduce arsenate phytoavailability.
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