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Combining metal and stable isotope analyses to disentangle contaminant transfer in a freshwater community dominated by alien species Full text
2021
Balzani, Paride | Haubrock, Phillip J. | Russo, Francesco | Kouba, Antonín | Haase, Peter | Veselý, Lukáš | Masoni, Alberto | Tricarico, Elena
Freshwater ecosystems are negatively impacted by various pollutants, from agricultural, urban and industrial wastewater, with metals being one of the largest concerns. Moreover, freshwater ecosystems are often affected by alien species introductions that can modify habitats and trophic relationships. Accordingly, the threat posed by metals interacts with those by alien species, since the latter can accumulate and transfer these substances across the food web to higher trophic levels. How metals transfer within such communities is little studied. We analysed the concentration of 14 metals/metalloids (Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mg, Mn, Ni, Pb, Se, Zn, hereafter ‘metal(s)’) of eight fish and three crustacean species co-existing in the Arno River (Central Italy), most of which were alien. To assess the pathway of contaminants within the community, we coupled metal analysis with carbon and nitrogen stable isotope analysis derived from the same specimens. Crustaceans showed higher metal concentration than fish, except for Cd, Hg and Se that were higher in fish. We found evidence of trophic transfer for six metals (Cd, Cr, Hg, Mg, Se, Zn). Additionally, ontogenetic differences and differences among various fish tissues (muscle, liver, and gills) were found in metals concentration. Considerable biomagnification along the trophic chain was found for Hg, while other metals were found to biodilute. Using stable isotopes and Hg as a third diet tracer, we refined the estimations of consumed preys in the diet previously reconstructed with stable isotope mixing models. Alien species reach high biomass and can both survive to and accumulate high pollutants concentrations, potentially posing a risk for their predators and humans. A combined effect of environmental filtering and increased competition may potentially contribute to the disappearance of native species with lower tolerances.
Show more [+] Less [-]Influence of fuel oil on Platymonas helgolandica: An acute toxicity evaluation to amino acids Full text
2021
Li, Na | Liu, Yu | Liang, Zhengyu | Lou, Yadi | Liu, Yuxin | Zhao, Xinda | Wang, Guoguang
It is highly likely that the toxicity of water accommodated fractions (WAF) will influence marine microalgae, and consequently lead to potential risk for the marine ecological environment. However, it was often neglected whether WAF can influence the transformation of relative compounds in organisms. The metabolism of amino acids (AAs) can be used to track physiological changes in microalgae because amino acids are the basis of proteins and enzymes. In this study, using marine Chlorophyta Platymonas helgolandica as the test organism, the effects of different concentrations of WAF on AA compositions and stable carbon isotope ratios (δ¹³C) of individual AAs of Platymonas helgolandica were investigated. The results showed that the WAF of #180 fuel oil had an obvious suppressing effect on the growth and chlorophyll a content of microalgae. The growth inhibitory rate at 96 h was 80.66% at a WAF concentration of 0.50 mg L⁻¹ compared with the control. Furthermore, seven among the 16 AAs, including alanine, cysteine, proline, aspartic acid, lysine, histidine and tyrosine, had relatively high abundance. Under the glycolysis pathway, the cysteine abundance was higher than control, meaning that the biosynthesized pathway of alanine through cysteine as a precursor could be damaged. Phosphoenolpyruvate (PEP) was an important synthesis precursor of alanine (leucine) and aromatic AA family (Phenylalanine and tyrosine), and played an important role in δ¹³CAAₛ fractionation under the WAF stress. Under the TCA pathway, to protect cell metabolism activities under WAF stress, the δ¹³C value of threonine and proline abundance in microalgae with the increase in WAF stress. Therefore, δ¹³CAAₛ fractionation can be used as a novel method for toxicity evaluation of WAF on future.
Show more [+] Less [-]Persistent pollutants in Northern Gannet Morus bassanus eggs in Ireland: Levels and colony differences Full text
2021
Power, Andrew | White, Philip | McHugh, Brendan | Berrow, Simon | Schlingermann, Moira | Tannian, Marissa | Newton, Stephen | McGovern, E. (Evin) | Murphy, Sinéad | Crowley, Denis | O’Hea, Linda | Boyle, Brian | O’Connor, Ian
Seabird eggs are considered a favourable matrix for monitoring marine pollutants and are widely used as higher trophic level indicators. Persistent organic pollutants such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and other organochlorine compounds (OCs) as well as metals have been shown to have deleterious impacts on seabirds. The Northern Gannet Morus bassanus is an avian sentinel; the largest breeding seabird in Ireland and an obligate piscivore. Gannet eggs were collected from two island colonies off the east coast of Ireland in locations with divergent history of industrialisation. Contaminant levels were measured and differences in concentrations between colonies compared. Stable isotope ratios of carbon (δ₁₃C) and nitrogen (δ₁₅N) were measured in each egg to understand the influence of diet and trophic position on contaminant levels detected. Significantly higher levels of Σ14PCBs, Σ7PBDEs and total mercury were detected in Gannet eggs from Lambay Island near Dublin (Ireland’s industrialised capital city) compared to Great Saltee Island. No differences were observed in levels of other OCs (HCB, ΣHCH, ΣCHL, ΣDDT) between the two colonies. Though Gannets travel significant distances when foraging for food, tracking studies have demonstrated that birds from proximal breeding colonies maintain exclusive feeding areas. Stable isotope ratio analysis in this study demonstrated that Gannets at both locations occupy similar dietary niches, indicating that dietary differences may not be the driver of differing contaminant levels between colonies. Levels of persistent pollutants in the Gannet eggs fall below most existing thresholds for adverse effects and are within internationally reported values. Recent population growth and range expansion of Gannets in Ireland suggest that persistent pollutants are not having an immediate impact on the Gannet population. This study will inform potential monitoring programmes that can help Ireland achieve good environmental status under the European Union’s Marine Strategy Framework Directive.
Show more [+] Less [-]Estimating NOx removal capacity of urban trees using stable isotope method: A case study of Beijing, China Full text
2021
Gong, Cheng | Xian, Chaofan | Cui, Bowen | He, Guojin | Wei, Mingyue | Zhang, Zhaoming | Ouyang, Z. (Zhiyun)
It is widely recognized that green infrastructures in urban ecosystems provides important ecosystem services, including air purification. The potential absorption of nitrogen oxides (NOₓ) by urban trees has not been fully quantified, although it is important for air pollution mitigation and the well-being of urban residents. In this study, four common tree species (Sophora japonica L., Fraxinus chinensis Roxb., Populus tomentosa Carrière, Sabina chinensis (L.)) in Beijing, China, were studied. The dual stable isotopes (¹⁵N and ¹⁸O) and a Bayesian isotope mixing model were applied to estimate the sources contributions of potential nitrogen sources to the roadside trees based on leaf and soil sampling in urban regions. The following order of sources contributions was determined: soil > dry deposition > traffic-related NOₓ. The capacity of urban trees for NOₓ removal in the city was estimated using a remote sensing and GIS approach, and the removal capacity was found to range from 0.79 to 1.11 g m⁻² a⁻¹ across administrative regions, indicating that 1304 tons of NOₓ could be potentially removed by urban trees in 2019. Our finding qualified the potential NOₓ removal by urban trees in terms of atmospheric pollution mitigation, highlighting the role of green infrastructure in air purification, which should be taken into account by stakeholders to manage green infrastructure as the basis of a nature-based approach.
Show more [+] Less [-]Characterization and source identification of organic phosphorus in sediments of a hypereutrophic lake Full text
2020
Yuan, Hezhong | Tai, Ziqiu | Li, Qiang | Zhang, Fengmin
High phosphorus (P) load and consequent algal bloom are critical issues because of their harmful effects to aquatic ecosystems. The organic phosphorus (Po) cycling and hydrolyzation pathway in the sediments of a hypereutrophic lake area with high algae biomass were investigated using stable isotopes (δ¹³C and δ¹⁵N) along with C/N ratios, a sequential extraction procedure, ³¹P NMR spectrum, and alkaline phosphatase activity (APA) was measured simultaneously. C/N ratios lower than 10 combined with lighter δ¹³C (−23.5 to −25.2‰) and δ¹⁵N values (3.7–9.5‰) indicated that endogenous algal debris contributed to the predominant proportions of P-containing organic matter in the sediments. Sequential extraction results showed that Po fractions decreased as nonlabile Po > moderately labile Po > biomass-Po. Decreasing humic-associated Po (HA-Po) in sediments downward suggested the degradation of high-molecular-weight Po compounds on the geological time scale to low-molecular-weight Po including fulvic-associated Po (FA-Po), which is an important source of labile Po in the sediment. An analysis of the solution ³¹P NMR spectrum analysis showed that important Po compound groups decreased in the order of orthophosphate monoesters > DNA-Po > phospholipids. The significant correlation indicated that orthophosphate monoesters were the predominant components of HA-Po. Rapid hydrolysis of labile orthophosphate diesters further facilitated the accumulation of orthophosphate monoesters in the sediments. Additionally, the simultaneously upward increasing trend demonstrated that APA accelerated the mineralization of Po into dissolved reactive phosphorus (DRP), which might feed back to eutrophication in algae-dominant lakes. The significantly low half-life time (T₁/₂) for important Po compound groups indicated faster metabolism processes, including hydrolysis and mineralization, in hypereutrophic lakes with high algae biomass. These findings provided improved insights for better understanding of the origin and cycling processes as well as management of Po in hypereutrophic lakes.
Show more [+] Less [-]Trophic transfer of persistent toxic substances through a coastal food web in Ulsan Bay, South Korea: Application of compound-specific isotope analysis of nitrogen in amino acids Full text
2020
An, Yoonyoung | Hong, Seongjin | Kim, Youngnam | Kim, Mungi | Choi, Bohyung | Won, Eun-Ji | Shin, Kyung-Hoon
Trophic magnification factor (TMF) of persistent toxic substances (PTSs: Hg, PCBs, PAHs, and styrene oligomers (SOs)) in a coastal food web (12 fish and four invertebrates) was determined in Ulsan Bay, South Korea. The nitrogen stable isotope ratios (δ¹⁵N) of amino acids [δ¹⁵NGₗᵤ₋Pₕₑ based on glutamic acid (δ¹⁵NGₗᵤ) and phenylalanine (δ¹⁵NPₕₑ)] were used to estimate the trophic position (TPGₗᵤ₋Pₕₑ) of organisms. The TPGₗᵤ₋Pₕₑ of organisms ranged from 1.64 to 3.69, which was lower than TP estimated by δ¹⁵N of bulk particulate organic matter (TPBᵤₗₖ: 2.46–4.21). Mercury and CB 138, 153, 187, and 180 were biomagnified through the whole food web (TMF > 1), while other PTSs, such as PAHs and SOs were not (biodilution of SOs firstly reported). In particular, the trophic transfer of PTSs was pronounced in the resident fish (e.g., rock bream, sea perch, Korean rockfish). Of note, CB 99, 101, 118, and 183 were additionally found to be biomagnifying PTSs in these species. Thus, fish residency appears to represent an important factor in determining the TMF of PTSs in the coastal environment. Overall, δ¹⁵NGₗᵤ₋Pₕₑ provided accurate TPs of organisms and could be applied to determine the trophic transfer of PTSs in coastal food webs.
Show more [+] Less [-]Influence of overwinter distribution on exposure to persistent organic pollutants (POPs) in seabirds, ancient murrelets (Synthliboramphus antiquus), breeding on the Pacific coast of Canada Full text
2020
Miller, Aroha | Elliott, John E. | Wilson, Laurie K. | Elliott, Kyle H. | Drouillard, Ken G. | Verreault, Jonathan | Lee, Sandi | Idrissi, Abde
Assessing the fate of both legacy and newer persistent organic pollutants (POPs) is an ongoing challenge. Top predators, including seabirds, are effective monitors of POPs because they forage over a range of marine habitats, integrating signals over space and time. However, migration patterns can make unravelling contaminant sources, and potentially assessments of the effectiveness of regulations, challenging if chemicals are acquired at distant sites. In 2014, we fitted geolocators on ancient murrelets (Synthliboramphus antiqueus) at four colonies on the Pacific Coast of Canada to obtain movement data throughout an annual cycle. All birds underwent a post-breeding moult in the Bering Sea. Around one-third then returned to overwinter on the British Columbia (BC) coast while the rest migrated to overwinter in waters along the north Asian coast. Such a stark difference in migration destination provided an opportunity to examine the influence of wintering location on contaminant signals. In summer 2015, we collected blood samples from returned geo-tagged birds and analyzed them for a suite of contaminants, including polybrominated diphenyl ethers (PBDEs), non-PBDE halogenated flame retardants, perfluoroalkyl substances (PFASs), organochlorines, and mercury. Feathers were also collected and analyzed for stable isotopes (δ¹³C, δ¹⁵N, and δ³⁴S). We found no significant differences in blood concentrations of any contaminant between murrelets from the two different overwinter areas, a result that indicates relatively rapid clearance of POPs accumulated during winter. Spatial variation in diet (i.e., δ¹³C) was associated with both BDE-47 and -99 concentrations. However, individual variation in trophic level had little influence on concentrations of any other examined contaminants. Thus, blood from these murrelets is a good indicator of recent, local contaminants, as most signals appear independent of overwintering location.
Show more [+] Less [-]Concentration and origin of lead (Pb) in liver and bone of Eurasian buzzards (Buteo buteo) in the United Kingdom Full text
2020
Taggart, Mark A. | Shore, Richard F. | Pain, Deborah J. | Peniche, Gabriela | Martinez-Haro, Mónica | Mateo, Rafael | Homann, Julia | Raab, Andrea | Feldmann, Joerg | Lawlor, Alan J. | Potter, Elaine D. | Walker, Lee A. | Braidwood, David W. | French, Andrew S. | Parry-Jones, Jemima | Swift, John A. | Green, Rhys E.
Ingestion of lead (Pb) derived from ammunition used in the hunting of game animals is recognised to be a significant potential source of Pb exposure of wild birds, including birds of prey. However, there are only limited data for birds of prey in Europe regarding tissue concentrations and origins of Pb. Eurasian buzzards (Buteo buteo) found dead in the United Kingdom during an 11-year period were collected and the concentrations of Pb in the liver and femur were measured. Concentrations in the liver consistent with acute exposure to Pb were found in 2.7% of birds and concentration in the femur consistent with exposure to lethal levels were found in 4.0% of individuals. Pb concentration in the femur showed no evidence of consistent variation among or within years, but was greater for old than for young birds. The Pb concentration in the liver showed no effect of the birds’ age, but varied markedly among years and showed a consistent tendency to increase substantially within years throughout the UK hunting season for gamebirds. The resemblance of the stable isotope composition of Pb from buzzard livers to that of Pb from the types of shotgun ammunition most widely-used in the UK increased markedly with increasing Pb concentration in the liver. Stable isotope results were consistent with 57% of the mass of Pb in livers of all of the buzzards sampled being derived from shotgun pellets, with this proportion being 89% for the birds with concentrations indicating acute exposure to Pb. Hence, most of the Pb acquired by Eurasian buzzards which have liver concentrations likely to be associated with lethal and sublethal effects is probably obtained when they prey upon or scavenge gamebirds and mammals shot using Pb shotgun pellets.
Show more [+] Less [-]Dust and bullets: Stable isotopes and GPS tracking disentangle lead sources for a large avian scavenger Full text
2020
Dust and bullets: Stable isotopes and GPS tracking disentangle lead sources for a large avian scavenger Full text
2020
Lead intoxication is an important threat to human health and a large number of wildlife species. Animals are exposed to several sources of lead highlighting hunting ammunition and lead that is bioavailable in topsoil. Disentangling the role of each in lead exposure is an important conservation issue, particularly for species potentially affected by lead poisoning, such as vultures. The identification of lead sources in vultures and other species has been classically addressed by means of stable-isotope comparisons, but the extremely varied isotope signatures found in ammunition hinders this identification when it overlaps with topsoil signatures. In addition, assumptions related to the exposure of individual vultures to lead sources have been made without knowledge of the actual feeding grounds exploited by the birds. Here, we combine lead concentration analysis in blood, novel stable isotope approaches to assign the origin of the lead and GPS tracking data to investigate the main foraging grounds of two Iberian griffon vulture populations (N = 58) whose foraging ranges differ in terms of topsoil lead concentration and intensity of big game hunting activity. We found that the lead signature in vultures was closer to topsoil than to ammunition, but this similarity decreased significantly in the area with higher big game hunting activity. In addition, attending to the individual home ranges of the tracked birds, models accounting for the intensity of hunting activity better explained the higher blood lead concentration in vultures than topsoil exposure. In spite of that, our finding also show that lead exposure from topsoil is more important than previously thought.
Show more [+] Less [-]Dust and bullets: Stable isotopes and GPS tracking disentangle lead sources for a large avian scavenger Full text
2020
Arrondo, Eneko | Navarro, Joan | Pérez-García, Juan M. | Mateo, Rafael | Camarero, Pablo R. | Rodríguez Martín-Doimeadios, Rosa C. | Jiménez-Moreno, María | Cortés-Avizanda, Ainara | Navas, Isabel | García-Fernández, Antonio J. | Sánchez-Zapata, José A. | Donázar, José A. | Bárdenas Reales de Navarra | Junta de Andalucía | Ministerio de Economía y Competitividad (España) | Junta de Comunidades de Castilla-La Mancha | La Caixa | Govern de les Illes Balears | Agencia Estatal de Investigación (España)
9 pages, 3 figures, 2 tables, supplementary data https://doi.org/10.1016/j.envpol.2020.115022 | Lead intoxication is an important threat to human health and a large number of wildlife species. Animals are exposed to several sources of lead highlighting hunting ammunition and lead that is bioavailable in topsoil. Disentangling the role of each in lead exposure is an important conservation issue, particularly for species potentially affected by lead poisoning, such as vultures. The identification of lead sources in vultures and other species has been classically addressed by means of stable-isotope comparisons, but the extremely varied isotope signatures found in ammunition hinders this identification when it overlaps with topsoil signatures. In addition, assumptions related to the exposure of individual vultures to lead sources have been made without knowledge of the actual feeding grounds exploited by the birds. Here, we combine lead concentration analysis in blood, novel stable isotope approaches to assign the origin of the lead and GPS tracking data to investigate the main foraging grounds of two Iberian griffon vulture populations (N = 58) whose foraging ranges differ in terms of topsoil lead concentration and intensity of big game hunting activity. We found that the lead signature in vultures was closer to topsoil than to ammunition, but this similarity decreased significantly in the area with higher big game hunting activity. In addition, attending to the individual home ranges of the tracked birds, models accounting for the intensity of hunting activity better explained the higher blood lead concentration in vultures than topsoil exposure. In spite of that, our finding also show that lead exposure from topsoil is more important than previously thought | The research was funded by Comunidad de Bardenas Reales de Navarra the Project RNM-1925 (Junta de Andalucía), Project CGL 2015-66966-C2-1-2-R (Spanish Ministry of Economy and Competitiveness and EU/ERDF) and Project PPII-2014-028-P (Junta de Comunidades de Castilla-La Mancha). EA was supported by La Caixa-Severo Ochoa International PhD Program 2015. JN was funded by the Spanish National Program Ramón y Cajal (RYC-2015-17809). ACA was supported by a PostDoc contract Programa Viçent Mut of Govern Balear (PD/039/2017) and and by a contract Juan de la Cierva Incorporación (IJCI-2014-20744) from the Spanish Ministry of Economy and Competitiveness | With the funding support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI)
Show more [+] Less [-]Humpback whales (Megaptera novaeangliae) breeding off Mozambique and Ecuador show geographic variation of persistent organic pollutants and isotopic niches Full text
2020
Remili, Anaïs | Gallego, Pierre | Pinzone, Marianna | Castro, Cristina | Jauniaux, Thierry | Garigliany, Mutien-Marie | Malarvannan, Govindan | Covaci, Adrian | Dāsa, Kr̥shṇā
Humpback whales (Megaptera novaeangliae) breeding off Mozambique and Ecuador show geographic variation of persistent organic pollutants and isotopic niches Full text
2020
Remili, Anaïs | Gallego, Pierre | Pinzone, Marianna | Castro, Cristina | Jauniaux, Thierry | Garigliany, Mutien-Marie | Malarvannan, Govindan | Covaci, Adrian | Dāsa, Kr̥shṇā
Humpback whales (Megaptera novaeangliae) from the Southern Hemisphere carry information on persistent organic pollutants (POPs) from their feeding zones in Antarctica to their breeding grounds, making this species a sentinel of contaminants accumulation in the Southern Ocean. This study aimed to evaluate driving factors, namely feeding areas, trophic level, and sex, affecting POP concentrations in the blubber of humpback whales breeding off Mozambique and off Ecuador. Biopsies of free-ranging humpback whales including blubber and skin were collected in 2014 and 2015 from Ecuador (n = 59) and in 2017 from Mozambique (n = 89). In both populations, HCB was the major contaminant followed by DDTs > CHLs > PCBs > HCHs > PBDEs. POP concentrations were significantly higher in males compared to females. HCB, DDTs, HCHs and PBDEs were significantly different between whales from the Mozambique population and the Ecuador population. Sex and feeding habits were important driving factors accounting for POP concentrations in Ecuador whales. The whales from our study had some of the lowest POP concentrations measured for humpback whales in the world. These whales fed predominantly on krill as reflected from the low δ¹³C and δ¹⁵N values measured in the skin. However, the isotopic niches of whales from Mozambique and Ecuador did not overlap indicating that the two populations are feeding in different areas of the Southern Ocean.
Show more [+] Less [-]Humpback whales (Megaptera novaeangliae) breeding off Mozambique and Ecuador show geographic variation of persistent organic pollutants and isotopic niches Full text
2020
Remili, Anaïs | Gallego Reyes, Pedro | Pinzone, Marianna | Castro, Cristina | Jauniaux, Thierry | Garigliany, Mutien-Marie | Malarvannan, Govindan | Covaci, Adrian | Das, Krishna | FOCUS - Freshwater and OCeanic science Unit of reSearch - ULiège
peer reviewed | Humpback whales (Megaptera novaeangliae) from the Southern Hemisphere carry information on persistent organic pollutants (POPs) from their feeding zones in Antarctica to their breeding grounds, making this species a sentinel of contaminants accumulation in the Southern Ocean. This study aimed to evaluate driving factors, namely feeding areas, trophic level, and sex, affecting POP concentrations in the blubber of humpback whales breeding off Mozambique and off Ecuador. Biopsies of free-ranging humpback whales including blubber and skin were collected in 2014 and 2015 from Ecuador (n = 59) and in 2017 from Mozambique (n = 89). In both populations, HCB was the major contaminant followed by DDTs > CHLs > PCBs > HCHs > PBDEs. POP concentrations were significantly higher in males compared to females. HCB, DDTs, HCHs and PBDEs were significantly different between whales from the Mozambique population and the Ecuador population. Sex and feeding habits were important driving factors accounting for POP concentrations in Ecuador whales. The whales from our study had some of the lowest POP concentrations measured for humpback whales in the world. These whales fed predominantly on krill as reflected from the low δ13C and δ15N values measured in the skin. However, the isotopic niches of whales from Mozambique and Ecuador did not overlap indicating that the two populations are feeding in different areas of the Southern Ocean. | EXPOSURE OF HUMPBACK WHALES FROM THE SOUTHERN HEMISPHERE TO PERSISTENT ORGANIC POLLUTANTS: INFLUENCE OF THEIR ISOTOPIC NICHE, SEX AND AGE DETERMINED BY EPIGENETICS
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